Rehabilitación cognitiva para los déficits de atención después de un accidente cerebrovascular
Resumen
Antecedentes
Muchos supervivientes de accidentes cerebrovasculares informan de problemas de atención, como la disminución de la concentración y la distracción. Sin embargo, la efectividad de la rehabilitación cognitiva para mejorar estas deficiencias no está clara. Esta es una actualización de una revisión Cochrane publicada por primera vez en 2000 y actualizada previamente en 2013.
Objetivos
Determinar si los pacientes que reciben rehabilitación cognitiva para los problemas de atención 1. muestran mejores resultados en las funciones de atención que los que reciben ningún tratamiento o tratamiento habitual, y 2. tienen una mejor recuperación funcional, en términos de independencia en las actividades de la vida cotidiana, el estado de ánimo y la calidad de vida, que los que reciben ningún tratamiento o tratamiento habitual.
Métodos de búsqueda
Se realizaron búsquedas en el Registro de Ensayos del Grupo Cochrane de Accidentes Cerebrales Vasculares (Cochrane Stroke Group), CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, PsycBITE, REHABDATA y en los registros de ensayos en curso hasta febrero de 2019. Se revisaron las listas de referencias y se hizo un seguimiento de las citas mediante Scopus.
Criterios de selección
Se incluyeron los ensayos clínicos controlados (ECC) y los ensayos controlados aleatorizados (ECA) de rehabilitación cognitiva para los trastornos de la atención de los pacientes con un accidente cerebrovascular. No se consideró que escuchar música ni realizar meditación, yoga o conciencia plena fueran formas de rehabilitación cognitiva. Sólo se consideraron los ensayos que seleccionaron pacientes con déficits atencionales demostrables o autoinformados. Las medidas de resultado primarias fueron medidas de las funciones globales de atención y las medidas de resultado secundarias fueron medidas de los dominios de atención (es decir, estado de alerta, atención selectiva, atención mantenida, atención compartida), las capacidades funcionales, el estado de ánimo y la calidad de vida.
Obtención y análisis de los datos
Dos autores de la revisión, de forma independiente seleccionaron los ensayos, extrajeron los datos y evaluaron el riesgo de sesgo. Se utilizaron los criterios GRADE para evaluar la certeza de la evidencia para cada resultado.
Resultados principales
No se incluyeron ensayos nuevos en esta actualización. Los resultados no varían con respecto a la revisión anterior y se basan en los datos de seis ECA con 223 participantes. Los seis ECA compararon la rehabilitación cognitiva con un control de atención habitual.
Los metanálisis no demostraron un efecto convincente de la rehabilitación cognitiva sobre las medidas subjetivas de atención, ya sea inmediatamente después del tratamiento (diferencia de medias estandarizada [DME] 0,53; intervalo de confianza [IC] del 95%: ‐0,03 a 1,08; p = 0,06; dos estudios, 53 participantes; evidencia de calidad muy baja) o durante el seguimiento (DME 0,16; IC del 95%: ‐0,23 a 0,56; p = 0,41; dos estudios, 99 participantes; evidencia de calidad muy baja).
Los pacientes que recibieron rehabilitación cognitiva (en comparación con control) mostraron que las medidas de atención compartida registradas inmediatamente después del tratamiento pueden mejorar (DME 0,67; IC del 95%: 0,35 a 0,98; p < 0,0001; cuatro estudios, 165 participantes; evidencia de calidad muy baja), pero no se sabe si estos efectos persistieron (DME 0,36; IC del 95%: ‐0,04 a 0,76; p = 0,08; dos estudios, 99 participantes; evidencia de calidad muy baja). No hubo evidencia de efectos inmediatos o persistentes de la rehabilitación cognitiva sobre el estado de alerta, la atención selectiva ni la atención mantenida.
No hubo evidencia convincente de efectos inmediatos o a largo plazo de la rehabilitación cognitiva en los problemas de atención en las capacidades funcionales, el estado de ánimo ni la calidad de vida después de un accidente cerebrovascular.
Conclusiones de los autores
La efectividad de la rehabilitación cognitiva para los déficits de atención después de un accidente cerebrovascular sigue sin confirmarse. Los resultados indican que puede haber un efecto inmediato después del tratamiento sobre las habilidades atencionales, pero los estudios futuros necesitan evaluar qué ayuda a que este efecto persista y a generalizar las capacidades de atención en la vida cotidiana. Los ensayos también deben tener una mayor calidad metodológica y un mejor informe.
PICO
Resumen en términos sencillos
Rehabilitación cognitiva para los déficits de atención después de un accidente cerebrovascular
Pregunta de la revisión
El objetivo fue revisar la evidencia acerca del efecto de la rehabilitación cognitiva sobre la atención, la capacidad para realizar las actividades cotidianas, el estado de ánimo y la calidad de vida en los pacientes que tienen problemas de atención después de un accidente cerebrovascular.
Antecedentes
Muchos pacientes tienen problemas de atención después de un accidente cerebrovascular. No se pueden concentrar durante períodos prolongados y se distraen, siendo incapaces de centrarse en una tarea específica en presencia de información concurrente. La "rehabilitación cognitiva" consiste en proporcionar actividades terapéuticas para reducir la gravedad de los problemas cognitivos, como la atención, después de un daño en el cerebro. El beneficio de la rehabilitación cognitiva para los problemas de atención después de un accidente cerebrovascular no está claro.
Características de los estudios
Se identificaron seis estudios que compararon la rehabilitación cognitiva con un grupo control que recibió atención habitual (pero no rehabilitación cognitiva) en pacientes con problemas de atención después de un accidente cerebrovascular. No se consideró que escuchar música ni realizar meditación, yoga o conciencia plena fueran formas de rehabilitación cognitiva. Los seis estudios incluyeron 223 participantes que demostraron problemas de atención o informaron tener tales problemas después de un accidente cerebrovascular. La evidencia está actualizada hasta febrero de 2019.
Resultados clave
No se encontró evidencia de que la rehabilitación cognitiva mejorara las medidas generales (globales) de atención. El grupo que recibió rehabilitación cognitiva tuvo un mejor desempeño que el grupo control en las tareas que requerían que los pacientes compartieran la atención. Sin embargo, este beneficio sólo se observó inmediatamente después del período de rehabilitación sin que se indicara que los beneficios persisten por más tiempo. No hubo evidencia que indicara que la rehabilitación cognitiva fue beneficiosa en otros tipos de problemas de atención o actividades de la vida cotidiana, el estado de ánimo o la calidad de vida. Se necesitan más estudios de investigación.
Certezade la evidencia
La calidad metodológica muy baja a moderada de los estudios identificados y la falta de estudios hizo que no se pudiera establecer conclusiones firmes acerca del efecto de la rehabilitación cognitiva en la atención después de un accidente cerebrovascular.
Authors' conclusions
Summary of findings
| Attention training compared to control for attention deficits following stroke immediately after treatment | |||||
| Patient or population: people with attention deficits following stroke | |||||
| Outcomes | No of participants | Certainty of the evidence | Estimated effect of intervention (SMD)b | 95% confidence interval of estimated effect | Comments |
| Subjective measures – assessed with Cognitive Failures Questionnaire & Mental Slowness Questionnaire | 53 | ⊕⊝⊝⊝ | 0.53 SMDs better | 0.03 SMDs worse to 1.08 SMDs better | — |
| Objective global measures | No studies | — | — | — | No data |
| Alertness – assessed with TAP phasic alertness, Wiener Reaktionsgerat Visual RT, Simple RT & Tempo‐Lern Test | 136 | ⊕⊕⊝⊝ | 0.14 SMDs better | 0.20 SMDs worse to 0.48 SMDs better | — |
| Selective attention – assessed with TAP selective attention, Trail Making A, Zahlen‐Verbindungstest, Wiener Reaktionsgerat Choice RT, Ruff 2&7 | 223 | ⊕⊕⊕⊝ | 0.08 SMDs worse | 0.35 SMDs worse to 0.18 SMDs better | — |
| Sustained attention – assessed with IVA‐CPT Fullscale Attention Quotient, d2, Konzentrations‐Verlaufs‐Test, Wiener Vigilanzgerat | 169 | ⊕⊕⊝⊝ | 0.39 SMDs better | 0.16 SMDs worse to 0.94 SMDs better | — |
| Divided attention – assessed with TAP divided attention, PASAT | 165 | ⊕⊕⊝⊝ | 0.67 SMDs better | 0.35 SMDs to 0.98 SMDs better | — |
| Functional abilities – assessed with Barthel, Functional Independence Measure (FIM) | 75 | ⊕⊝⊝⊝ | 0.29 SMDs better | 0.16 SMDs worse to 0.75 SMDs better | — |
| Mood (depression) – assessed with Center for Epidemiologic Studies Depression Scale, Zung Depression Status Inventory, Emotional State Questionnaire (Depression subscale) | 109 | ⊕⊕⊝⊝ | 0.01 SMDs better | 0.36 SMDs worse to 0.39 SMDs better | — |
| Quality of life – assessed with SF‐36 (Mental Component Summary subscale), EQ‐VAS | 103 | ⊕⊕⊝⊝ | 0.02 SMDs better | 0.37 SMDs worse to 0.40 SMDs better | — |
| CI: confidence interval; IVA‐CPT: Integrated Visual and Auditory Continuous Performance Test; n: number of participants; PASAT: Paced Auditory Serial Addition Test; RCT: randomised controlled trial; ROB: risk of bias; RT: reaction time; SF‐36: 36‐item Short Form; SMD: standardised mean difference; TAP: Tests of Attentional Performance. | |||||
| GRADE Working Group grades of evidence | |||||
| aDowngraded for imprecision: two levels for 1–99 participants; one level for 100–199 participants; no downgrade > 199 participants. | |||||
| Attention training compared to control for attention deficits following stroke 3–6 months after treatment | |||||
| Patient or population: people with attention deficits following stroke | |||||
| Outcomes | No of participants | Certainty of the evidence | Estimated effect of intervention (SMD)b | 95% confidence interval of estimated effect | Comments |
| Subjective measures – assessed with Cognitive Failures Questionnaire & Mental Slowness Questionnaire | 99 | ⊕⊝⊝⊝ | 0.16 SMDs better | 0.23 SMDs worse to 0.56 SMDs better | — |
| Objective global measures | No studies | — | — | — | No data |
| Alertness – assessed with Simple RT | 31 | ⊕⊝⊝⊝ | 0.26 SMDs worse | 0.97 SMDs worse to 0.45 SMDs better | — |
| Selective attention – assessed with Trail Making A | 99 | ⊕⊝⊝⊝ | 0.07 SMDs better | 0.32 SMDs worse to 0.47 SMDs better | — |
| Sustained attention – assessed with IVA‐CPT Fullscale Attention Quotient | 66 | ⊕⊝⊝⊝ | 0.05 SMDs better | 0.44 SMDs worse to 0.53 SMDs better | — |
| Divided attention – assessed with PASAT | 99 | ⊕⊝⊝⊝ | 0.36 SMDs better | 0.04 SMDs to 0.76 SMDs better | — |
| Functional abilities – assessed with Modified Rankin | 66 | ⊕⊝⊝⊝ | 0.02 SMDs better | 0.46 SMDs worse to 0.51 SMDs better | — |
| Mood – assessed with Center for Epidemiologic Studies Depression Scale, General Health Questionnaire | 99 | ⊕⊝⊝⊝ | 0.29 SMDs better | 0.11 SMDs worse to 0.69 SMDs better | — |
| Quality of life – assessed with SF‐36 (Mental Component Summary subscale), EQ‐VAS | 99 | ⊕⊝⊝⊝ | 0.26 SMDs better | 0.13 SMDs worse to 0.66 SMDs better | — |
| CI: confidence interval; IVA‐CPT: Integrated Visual and Auditory Continuous Performance Test; PASAT: Paced Auditory Serial Addition Test; RCT: randomised controlled trial; ROB: risk of bias; RT: reaction time; SF‐36: 36‐item Short Form; SMD: standardised mean difference. | |||||
| GRADE Working Group grades of evidence | |||||
| aDowngrades for imprecision: two levels for 1–99 participants; one level for 100–199 participants; no downgrade > 199 participants. | |||||
Background
Description of the condition
Deficits in attention are one of the most commonly observed cognitive impairments after stroke. The exact frequency of attentional deficits after stroke is a matter of debate. Within the acute phase, estimates range between 46% and 92% (Stapleton 2001). At discharge from hospital, estimates suggest a prevalence between 24% and 51% (Hyndman 2008). Speed of information processing can also be impaired, and estimates have varied between 50% and 70% (Hochstenbach 1998; Rasquin 2004). Attentional deficits may recover over time in some people (Hochstenbach 2003), but in 20% to 50% of stroke survivors there are persistent deficits for years (Barker‐Collo 2010; Hyndman 2003).
Attentional impairments manifest themselves in a wide variety of deficits, such as diminished concentration, distractibility, reduced error control, difficulties doing more than one thing at a time, mental slowness, and mental fatigability. Being a mediator of other processes, attentional deficits may also impair higher cognitive functions, such as language and memory (Lezak 2004). While there is a consensus that attention is not a unitary process, there is no agreement on the typologies and taxonomies describing the range of attentional processes. For the current review, we considered the following attentional components: alertness/arousal, selective attention, sustained attention (vigilance), and divided attention (see Table 1). The rehabilitation of deficits in spatial attention is covered in a separate Cochrane Review (Bowen 2013), and therefore not covered in this review.
| Study ID | Subjective global measure | Objective global measure | Alertness | Selective attention | Sustained attention | Divided attention |
| Cognitive Failures Questionnairea | — | — | Trail Making Ab | IVA‐CPT Full‐Scale Attention Quotientb | PASAT (2.4 sec ISI)b | |
| — | — | TAP phasic alertness | TAP selective attention | d2 (Hits‐Errors) | TAP divided attention | |
| — | — | Tempo‐Lern‐Test (1st block) | Zahlen‐Verbindungstest | Konzentrations‐Verlaufs‐Test (combined speed/errors scores) | — | |
| — | — | Wiener Reaktionsgerat Visual RT | Wiener Reaktionsgerat Choice RT | Wiener Vigilanzgerat (Hits) | — | |
| Cognitive Failures Questionnaire | — | — | Ruff 2&7 | — | PASAT (2.4 sec ISI) | |
| Mental Slowness Questionnaireb | — | Simple RTb | Trail Making A (time)b | — | PASAT (3.2 sec ISI)b |
aOnly measured at follow‐up, but not after treatment.
bMeasured after treatment and at follow‐up.
ISI: interstimulus interval; IVA‐CPT: Integrated Visual and Auditory Continuous Performance Test; PASAT: Paced Auditory Serial Addition Test; RT: reaction time; TAP: Tests of Attentional Performance.
Table 1: Domains of attention
| Domain of attention | Definition | Functional example |
| Alertness/arousal | Ability and readiness to respond | Response to warning signals |
| Selective attention | Ability to focus on specific stimuli while ignoring irrelevant stimuli | Reading while people talk in the background |
| Sustained attention (vigilance) | Ability to maintain attention over a prolonged period of time | Driving a car for long distances |
| Spatial attention | Ability to detect and deploy attention to all sides of space | Attending to people sitting on left and right side of the table |
| Divided attention | Ability to multitask and to divide attention between 2 or more tasks | Talking on the telephone while cooking |
A distinction between different attentional domains is potentially important when evaluating rehabilitation. There is some evidence that attentional components need to be trained separately as there is little generalisation of treatment from one attentional domain to another (Sturm 1991; Sturm 1997). Moreover, cognitive training for certain domains, such as divided and selective attention, may be more effective than training for other domains, such as alertness and sustained attention (Cappa 2005).
The treatment of cognitive deficits is necessary because these deficits have a negative effect on functional abilities (Barker‐Collo 2006), and quality of life (Kwa 1996; Mitchell 2010; Nys 2006). Sustained attention (concentration) is an important prerequisite for motor recovery since sufficient sustained attention is required for learning (Robertson 1997). Deficits in attention can affect the ability to engage with other rehabilitation required for poststroke recovery (e.g. physiotherapy) and are associated with increased risk of falls (Hyndman 2003). Other specific attentional disorders, such as auditory and visual selective attention, and divided attention, also affect functional recovery (Hyndman 2008; Stapleton 2001).
Description of the intervention
Cognitive rehabilitation interventions typically focus on re‐establishing previously learned behaviours, developing new behaviours to compensate for cognitive deficits, and adapting to these cognitive deficits (Cicerone 2000). These interventions are guided and informed by psychological theories and models of behaviour and behaviour change, and cognitive or neuropsychological models of brain‐behaviour interactions.
For people with attentional deficits, cognitive rehabilitation interventions include tasks designed to restore attention abilities, such as computerised activities and pencil‐and‐paper tasks requiring attention. The alternative approach is teaching people strategies to compensate for their attention impairments. Attempts to retrain attentional skills have mainly relied on a restitution approach, although trials of attentional rehabilitation for people with other forms of brain injury, for instance traumatic brain injury, have emphasised the development of compensatory strategies rather than the restoration of basic aspects of attention (Cicerone 2005).
Defining cognitive rehabilitation simply on the basis of its impact on 'attention' (or 'cognition' more broadly), however, is not straightforward. For instance, some pharmacological interventions, mindfulness interventions, and listening to music have positive effects on cognition (e.g. Särkämö 2008; Zeidan 2010). However, such interventions, although positively affecting cognition, are not usually regarded as 'cognitive rehabilitation' interventions based on the purported mechanisms of action (see below). Ultimately, cognitive rehabilitation, regardless of its focus or strategy, aims to improve the person's function in their daily life (Ben‐Yishay 1990; Cicerone 2000; Sohlberg 1989).
How the intervention might work
Cognitive rehabilitation is based on two main principles. One is 'restitution', which aims to restore cognitive function through repeated practice. The other is 'compensation', which aims to reduce the effects of cognitive impairment on functional abilities using strategies that minimise demands on attention skills.
Why it is important to do this review
Impairments of attention are a major problem for people with stroke and affect rehabilitation outcome, but the effectiveness of cognitive rehabilitation for attention is uncertain. Finding the best ways to improve cognition is a top 10 research priority for stroke survivors (Pollock 2012). In one survey of stroke survivor needs, 84% of 799 respondents reported that their needs were not fully met in relation to their concentration problems (McKevitt 2010). While attention training has been provided for some people with stroke, it needs further evaluation. There have been few studies that have used control groups, and most evaluations have been based on single‐case experimental designs. Although these indicate treatment can be effective, they do not evaluate the general applicability of the findings. This updated review considered the evidence from controlled clinical trials (CCTs) and randomised controlled trials (RCTs) of the effectiveness of cognitive rehabilitation for attention.
Objectives
To determine whether people receiving cognitive rehabilitation for attention problems 1. show better outcomes in their attentional functions than those given no treatment or treatment as usual, and 2. have a better functional recovery, in terms of independence in activities of daily living, mood and quality of life, than those given no treatment or treatment as usual.
Methods
Criteria for considering studies for this review
Types of studies
In the first version of this review, we sought all controlled trials which compared cognitive rehabilitation with a control treatment. In the second version of the review, we excluded all non‐randomised trials to reduce selection bias. In this third update, we included quasi‐randomised or CCTs, as per the updated guidance in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We also reviewed those non‐randomised trials which we excluded from the previous versions of the review to check these against the updated criteria. We decided to do this in advance of searching the literature. We sought RCTs and CCTs in which an attentional treatment was compared with a control. We also sought cross‐over RCTs, but only included the outcomes between groups at the pre‐cross‐over period.
Types of participants
This review was confined to trials that selected people with demonstrable (on formal attention testing) or self‐reported attentional deficits following stroke. We excluded trials in which participant selection for attentional training was based on general cognitive impairments (e.g. as assessed with the Mini‐Mental State Examination) or other cognitive functions (e.g. aphasia). The participants were restricted to those with stroke. We excluded trials that included participants with mixed aetiologies unless separate data were available relating to people with stroke or if the trials had more than 75% of people with stroke in their sample.
Types of interventions
We included trials in which there was a comparison between a treatment group that received one of various attentional treatment strategies and a control group that received either an alternative form of treatment or no attentional intervention. We considered attention treatments to be any form of intervention with the aim of improving attention abilities. Alternative forms of treatment included computerised activities with low attentional demands and social activities. We excluded interventions that specifically aimed to improve spatial attentional deficits, as this has been the focus of a separate Cochrane Review (Bowen 2013). We did not consider listening to music, meditation, tai‐chi, yoga, or mindfulness to be a form of cognitive rehabilitation, although we acknowledge that these interventions may have a positive effect on attention. In a similar vein, we did not include trials with only a single treatment session or pharmacological studies.
Types of outcome measures
The primary outcome was measures of global attentional functions, and the secondary outcomes were measures of the individual domains of attention, functional abilities in activities of daily living (ADL), mood, and quality of life. We assessed the outcomes immediately after treatment and at follow‐up. We defined 'long‐term' follow‐up as more than three months after the intervention. We did not include studies in which the outcome was related exclusively to any single activity of daily living (e.g. driving a car).
Primary outcomes
Subjective reports of global attention as measured by validated rating scales, such as:
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Rating Scale of Attentional Behaviour (Ponsford 1991);
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Moss Attention Rating Scale (Whyte 2003);
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Attention Rating and Monitoring Scale (Cicerone 2002);
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Cognitive Failures Questionnaire (Broadbent 1982).
If an individual study reported more than one of these scales, we used the scale listed first.
Objective reports of global attention as measured by validated batteries assessing a wide range of attentional domains
We were not aware of any assessment batteries with a global score of attention at the start of this review. Batteries such as Test of Everyday Attention do not provide a total score (Robertson 1994). We included any validated assessments reporting global scores of attention.
Secondary outcomes
Objective reports of domains of attention as measured by:
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tests of alertness/arousal;
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tests of selective attention;
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tests of sustained attention;
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tests of divided attention.
We assigned each attentional test to a primary and a secondary attentional domain (see Appendix 1). For each trial, we only included one test measure in the analysis for a specific domain. We chose measures allocated to a primary domain over those allocated to secondary domains. We used the following hierarchy if a trial provided several measures for the same domain: combined error/speed measures > error measures > speed measures (median reaction times (RTs) > mean RTs). In the case when several tests were used to assess the same attentional domain within the same trial, we chose validated tests in preference to non‐validated tests. If two or more standardised tests were used to assess the same attentional domain, we chose the one with the higher reliability and validity rating based on information from the Compendium of Neuropsychological Tests (Strauss 2006). If we could not decide with the above criteria, we selected one of the tests at random.
Reports of functional abilities in daily living, mood, and quality of life
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Functional abilities as measured by scales such as the Nottingham Extended Activities of Daily Living (NEADL; Nouri 1987), Functional Independence Measure (Granger 1994), Barthel Index (Mahoney 1965), and Stroke Impact Scale (Duncan 2003).
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Mood as measured by scales such as the General Health Questionnaire (GHQ; Goldberg 1972), and Hospital Anxiety and Depression Scale (HADS; Zigmond 1983).
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Quality of life, as measured by the World Health Organization Quality of Life (WHOQOL; WHOQOL Group 1998), and 36‐item Short Form (SF‐36; Ware 1992).
If more than one of these scales were reported, we used the scale listed first.
Search methods for identification of studies
See the 'Specialised register' information available at the Cochrane Stroke Group's website (www.dcn.ed.ac.uk/csrg/entity/searchmethods.pdf). We searched for relevant trials in all languages and arranged for the translation of trial reports published in languages other than English where necessary.
Electronic searches
We searched the Cochrane Stroke Group Register (last searched February 2019). In addition, we searched the following databases and registries:
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the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 2 in the Cochrane Library; Appendix 2);
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MEDLINE Ovid (from 1948; Appendix 3);
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Embase Ovid (from 1947; Appendix 4);
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PsycINFO Ovid (from 1806; Appendix 5);
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Cumulative Index to Nursing and Allied Health Literature (CINAHL) EBSCO (from 1981; Appendix 6);
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Psychological Database for Brain Impairment Treatment Efficacy (PsycBITE, www.psycbite.com/; Appendix 7);
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REHABDATA (www.naric.com/research/rehab/; Appendix 8);
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US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (www.clinicaltrials.gov/; Appendix 9);
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World Health Organization International Clinical Trials Registry Platform (WHO ICTRP; apps.who.int/trialsearch; Appendix 10).
We developed the MEDLINE search strategy with the help of the Cochrane Stroke Group Information Specialist and modified it for the other databases. The search strategy included Cochrane's highly sensitive search strategies for identification of RCTs, as described in the Cochrane Handbook for Systematic Reviews of Interventions (Lefebvre 2011), and the Cochrane Stroke Group's search strategies for the identification of stroke studies in respective databases and other resources. The Cochrane Stroke Group Trials Information Specialist checked the search strategies from the previous review (no changes made). To identify new articles since the last review, the searches for this update were run from January 2012 to February 2019.
Searching other resources
To identify further published, unpublished, and ongoing trials, we scanned citations of the primary study articles, and we scanned reference lists from review articles and books identified in the searches.
For a previous version of this review, we conducted a handsearch of the following journals.
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American Journal of Occupational Therapy (1947 to 1998); Aphasiology (1987 to 1998); Australian Journal of Occupational Therapy (1965 to 1998); British Journal of Occupational Therapy (1950 to 1998); British Journal of Therapy and Rehabilitation (1994 to 1998); Canadian Journal of Occupational Therapy (1970 to 1998); Clinical Rehabilitation (1987 to 1998); Disability and Rehabilitation (1992 to 1998) formerly International Disability Studies (1987 to 1991) formerly International Rehabilitation Medicine (1979 to 1986); International Journal of Language and Communication Disorders (1998) formerly European Journal of Disorders of Communication (1985 to 1997) formerly British Journal of Disorders of Communication (1977 to 1984); Journal of Clinical Psychology in Medical Settings (1994 to 1998) formerly Journal of Clinical Psychology (1944 to 1994); Journal of Developmental and Physical Disabilities (1992 to 1998) formerly Journal of the Multihandicapped Person (1989 to 1991); Journal of Rehabilitation (1993 to 1998); International Journal of Rehabilitation Research (1977 to 1998); Journal of Rehabilitation Sciences (1989 to 1996); Neuropsychological Rehabilitation (1987 to 1998); Neurorehabilitation (1991 to 1998); Occupational Therapy International (1994 to 1998); Physiotherapy Theory and Practice (1990 to 1998) formerly Physiotherapy Practice (1985 to 1989); Physical Therapy (1988 to 1998); Rehabilitation Psychology (1982 to 1998); Journal of Cognitive Rehabilitation (1988 to 1998) formerly Cognitive Rehabilitation (1983 to 1987).
Since handsearching these journals in 1999, many have been updated as part of Cochrane's handsearching effort. After checking the Master List of journals that was maintained by Cochrane, we were confident that relevant trials would be found from the search of CENTRAL. Therefore, we did not repeat handsearching of these journals.
Data collection and analysis
Selection of studies
We completed study selection for this update using the Covidence systematic review software (Covidence).
One review author (KJP) screened all the titles and abstracts of records obtained from the searches of the electronic databases and another review author (TL, RdN, or DW) independently reviewed all studies and excluded those that were clearly not relevant. We obtained the full text of the remaining studies (where possible) and two review authors independently assessed which studies met the inclusion criteria in relation to study type, participants, interventions, comparisons, and outcomes (KJM reviewed all studies, with the remaining review authors splitting the studies as second review authors). Two review authors (KJP, TL) resolved any disagreements by discussion.
Data extraction and management
For each of the studies meeting the inclusion criteria, we extracted the following characteristics:
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method of participant assignment and blinding;
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setting and participant details (including age, gender, time since stroke, eligibility criteria);
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intervention (including comparison intervention, treatment durations);
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outcome measures (including assessment methods and time points of assessments);
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results.
One review author (TL) extracted the study characteristics, and a second review author (KJP) checked the details.
Assessment of risk of bias in included studies
We applied Cochrane's recommended approach for assessing risk of bias in studies included in Cochrane Reviews (Higgins 2011). Two review authors (TL, KJP) assessed the methodological quality of each study in the following six domains: sequence generation, allocation concealment, blinding, incomplete outcome data, selective outcome reporting, and 'other issues'. We judged each of these domains as either having a 'low', 'unclear', or 'high' risk of bias. We resolved disagreements by discussion. We used the results of the 'Risk of bias' assessment to inform the GRADE assessment.
Measures of treatment effect
We summarised ordinal scales using methods for continuous data. We expressed the intervention effect as a mean difference (MD) where studies measured outcomes using the same scales, or standardised mean difference (SMD) where studies used different scales, with the corresponding 95% confidence interval (CI). For some scales, a higher score indicated better ability/performance, and for others higher scores indicated worse ability/performance. Therefore, we multiplied the mean values from one set of studies by –1 to ensure that all the scales pointed in the same direction.
Unit of analysis issues
There were no unit of analysis issues. Four of the six identified studies used parallel group designs. For the two cross‐over RCTs, we only considered the outcomes between groups at the precross‐over period (Röhring 2004; Sturm 1991).
Dealing with missing data
We sought data that were not available or were unclear from the reports through correspondence with the first author of the publication. If we could not obtain the required information for an included study, we did not include that study in the analysis.
Assessment of heterogeneity
We assessed statistical heterogeneity using Chi2 statistics and I2 statistic estimates to quantify inconsistency across trials (Higgins 2011). We considered an I2 value above 50% to indicate substantial heterogeneity and 75% to indicate considerable heterogeneity.
Assessment of reporting biases
As no trials registers and study protocols were available for the identified studies, we investigated selective reporting by comparing the methods section of the studies with the results reported. We did not inspect funnel plots for publication biases due to the small sample size of fewer than 10 studies (Higgins 2011).
Data synthesis
We conducted a meta‐analysis using the Review Manager software RevMan 5.3 (Review Manager 2014). A fixed‐effect model with 95% CI was used if there was acceptable heterogeneity between trials (I2 < 50%). We used a random‐effects model for the meta‐analysis if we judged the characteristics of studies to be similar and heterogeneity was not considerable (i.e. I2 < 75%). If we judged studies to be dissimilar (e.g. considerable variation in study characteristics, or considerable heterogeneity (I2 > 75%)), we would have reported outcomes narratively. In the case of considerable heterogeneity, we would have explored subgroup analyses.
GRADE and 'Summary of findings' table
We used the GRADE approach to assess the certainty of evidence (Guyatt 2008). We downgraded evidence by one level ('high quality' to 'moderate quality') for serious study limitations related to 1. risk of bias, 2. consistency of evidence, 3. directness of evidence, and 4. imprecision of effect estimates. In case of very serious limitations, we downgraded the certainty of evidence by two levels. We created 'Summary of findings' tables to provide synthesised information regarding the overall certainty of evidence for the primary and secondary outcomes. We used GRADEpro GDT software to construct the tables (GRADEpro GDT 2015).
Subgroup analysis and investigation of heterogeneity
If sufficient data were available, we planned to perform subgroup analyses to determine whether outcomes varied according to time since onset of stroke, frequency of intervention (number of sessions per week), intensity of intervention (total hours of intervention), and type of intervention.
Sensitivity analysis
We planned a sensitivity analysis on the methodological quality of studies by excluding studies with high risk of bias.
Results
Description of studies
See Characteristics of included studies table.
Results of the search
The searches for studies in the previous reviews identified 2785 records. The search for this update was completed in February 2019 and retrieved 3960 new records. Initial screening of the 6745 records identified 130 possibly relevant studies. An in‐depth assessment of these papers identified six studies (11 records) that met the inclusion criteria. The study selection process is outlined in Figure 1.
Study flow diagram. CCT: controlled clinical trial; RCT: randomised controlled trial.
Of the 119 studies that we excluded, 14 were duplicate records of studies and 87 did not meet the inclusion criteria. The reasons for exclusion of studies are summarised in the Characteristics of excluded studies table. We excluded 56 studies because they were not stroke (i.e. less than 75% of study participants had a stroke) or participants were not selected because of attentional problems. We excluded 16 studies because they were not CCTs or RCTs, and 15 studies because they did not involve cognitive rehabilitation for attention impairments. We excluded a further 16 studies because insufficient information was available to make a decision at this stage (see Characteristics of studies awaiting classification table), and we two studies are ongoing (see Characteristics of ongoing studies table).
Included studies
We included six studies treating attentional deficits after stroke in this review (see Characteristics of included studies table). The six studies included 223 participants. Of the six RCTs, four used a parallel group design (Barker‐Collo 2009; Schottke 1997; Westerberg 2007; Winkens 2009), and two used a cross‐over design (Röhring 2004; Sturm 1991). Five studies reported the method of generating the random schedule. Two of these used random number tables (Röhring 2004; Sturm 1991), one used an online Internet randomisation service (Barker‐Collo 2009), one used coin tossing (Schottke 1997), one used drawing numbers from a bucket (Westerberg 2007), and in one this was unclear (Winkens 2009). Three studies generated the sequence independently (Barker‐Collo 2009; Westerberg 2007; Winkens 2009), and it was unclear in the other three (Röhring 2004; Schottke 1997; Sturm 1991). In all studies, the participants and therapists were aware of the treatment being given. Three studies assessed outcomes using a blinded assessor (Barker‐Collo 2009; Röhring 2004; Winkens 2009), in two the therapist conducted the outcome assessments (Schottke 1997; Westerberg 2007), and in one this was unclear (Sturm 1991).
One study was conducted in New Zealand (Barker‐Collo 2009), and five in Europe: three in Germany (Röhring 2004; Schottke 1997; Sturm 1991), one in Sweden (Westerberg 2007), and one in the Netherlands (Winkens 2009). The number of participants recruited to the studies varied between 78 (Barker‐Collo 2009), and 18 (Westerberg 2007). Four studies included only participants with stroke (Barker‐Collo 2009; Schottke 1997; Westerberg 2007; Winkens 2009). Two studies recruited most participants within the first two months after stroke (Barker‐Collo 2009; Schottke 1997), three mainly within one year of stroke (Sturm 1991; Westerberg 2007; Winkens 2009), and one study recruited participants up to four years after stroke (Röhring 2004). Three studies recruited participants with both right and left hemisphere lesions (Barker‐Collo 2009; Schottke 1997; Westerberg 2007), one included people with left hemisphere lesions in the randomised trial (Sturm 1991), and two studies did not report this information (Röhring 2004; Winkens 2009). The mean age of the samples was under 65 years in all except one study (Barker‐Collo 2009). The proportion of men ranged between 51% (Schottke 1997), and 70% (Sturm 1991).
Two studies identified attention deficits on tests of attention using specified cut‐offs (Barker‐Collo 2009; Schottke 1997), two studies on tests for attention without specification of cut‐offs (Röhring 2004; Sturm 1991), and two studies on self‐ or therapist‐reported attention deficits (Westerberg 2007; Winkens 2009). Groups were well matched at baseline apart from three studies. In two studies, the time after stroke was shorter for controls than intervention group participants (Schottke 1997; Winkens 2009), and in one study, the control group had more people with aphasia and scored lower in tasks assessing reasoning abilities (Sturm 1991).
Interventions aimed to either restore attentional functions (Barker‐Collo 2009; Röhring 2004; Schottke 1997; Sturm 1991; Westerberg 2007), or provide compensatory strategies (Winkens 2009). One study applied both intervention approaches (Schottke 1997). Interventions lasted from three weeks (Schottke 1997; Sturm 1991), to 11 weeks (Röhring 2004), and the number of sessions of treatment varied between 13 (Schottke 1997), and 55 (Röhring 2004), for the restorative approaches. The compensatory approach was delivered for 10 hours (Winkens 2009). The control groups in all studies received usual care with no treatment of attention deficits.
The six studies used over 30 psychometric tests with more than 40 test variables as attentional outcome measures. Four of the six studies assessed at least one functional outcome (Barker‐Collo 2009; Röhring 2004; Schottke 1997; Winkens 2009). All studies reported outcomes immediately after treatment; two studies also reported outcomes of follow‐up assessments (long‐term effects) (Barker‐Collo 2009; Winkens 2009).
For measures of attention, the findings of four individual studies supported the efficacy of treatment (Barker‐Collo 2009; Schottke 1997; Westerberg 2007; Sturm 1991), but two studies found limited evidence of benefit (Röhring 2004; Winkens 2009).
Risk of bias in included studies
The risk of bias for each study is summarised in Figure 2. An overview of the risk across all studies is provided in Figure 3.
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
Allocation
While all six studies were described as randomised, there were insufficient details available in one study to judge the risk of bias for the randomisation process (Winkens 2009). In three out of the six studies, there was insufficient information to allow judgement of the risk of an allocation concealment bias (Röhring 2004; Schottke 1997; Sturm 1991).
Blinding
All studies compared the effect of an intervention with care as usual. Blinding of the participants and therapists was not possible once the intervention started, and therefore no studies were double‐blind. Two studies showed a high risk of detection bias as the outcome assessment was not conducted blinded to the group allocation (Schottke 1997; Westerberg 2007). One study is at unclear risk as there was insufficient information to judge the risk of a detection bias (Sturm 1991).
Incomplete outcome data
All studies were at low risk of attrition bias. Dropouts from studies appeared generally balanced across groups (6.8% for the treatment groups and 5.3% for the control groups).
Selective reporting
There was no indication of any selective reporting, but none of the trials appeared to be prospectively registered on trial registries.
Effects of interventions
See: Summary of findings for the main comparison Attention training compared to control for attention deficits following stroke immediately after treatment; Summary of findings 2 Attention training compared to control for attention deficits following stroke at follow‐up
We assessed the effect of interventions immediately after treatment and at follow‐up. The included studies applied diverse outcome measures. The measures we chose for the analysis of treatment effects on attentional and functional outcomes are listed in Table 1 and Table 2.
| Study ID | Functional abilities | Mood | Quality of life |
| Modified Rankina | GHQa | SF‐36 (MCS subscale)b | |
| FIM | DSI | — | |
| Barthel | EMO‐D | — | |
| — | CES‐Db | EQ‐VASb |
aOnly measured at follow‐up, but not after treatment.
bMeasured after treatment and at follow‐up.
CES‐D: Center for Epidemiologic Studies Depression Scale; DSI: Zung Depression Status Inventory; EMO‐D: Emotional State Questionnaire (Depression subscale); FIM: Functional Independence Measure; GHQ: General Health Questionnaire; MCS: Mental Component Summary; VAS: visual analogue scale.
Primary outcomes
Effects immediately after treatment
Two studies involving 53 participants assessed subjective reports of global attentional functions with either the Cognitive Failures Questionnaire (Westerberg 2007), or the Mental Slowness Questionnaire (Winkens 2009). There was a no convincing effect in favour of the intervention compared with care as usual (SMD 0.53, 95% CI –0.03 to 1.08; P = 0.06; very low‐quality evidence; Analysis 1.1).
Long‐term effects
The two studies involving 99 participants investigating long‐term effects on subjective reports of global attentional functions found no evidence for effects of treatment (SMD 0.16, 95% CI –0.23 to 0.56; P = 0.41; very low‐quality evidence; Analysis 2.1) (Barker‐Collo 2009; Winkens 2009).
We identified no studies that reported objective measures of global attention at the end of treatment or in the longer term.
Secondary outcomes
Effects immediately after treatment
People receiving cognitive rehabilitation (when compared with control) showed improvements on measures of divided attention recorded immediately after treatment. Four studies comprising 165 participants assessed divided attention using the Paced Auditory Serial Addition Test (PASAT) (Barker‐Collo 2009; Westerberg 2007; Winkens 2009), or the divided attention subtest from the Tests of Attentional Performance battery (TAP) (Röhring 2004). The analysis found that the intervention was beneficial compared with care as usual (SMD 0.67, 95% CI 0.35 to 0.98; P < 0.0001; low‐quality evidence; Analysis 3.4).
We found no convincing effects on other domains of attention. Four studies comprising 136 participants investigated an effect on alertness (SMD 0.14, 95% CI –0.20 to 0.48; P = 0.41; low‐quality evidence; Analysis 3.1; Röhring 2004; Schottke 1997; Sturm 1991; Winkens 2009). Six studies comprising 223 participants examined the effects on selective attention (SMD –0.08, 95% CI –0.35 to 0.18; P = 0.53; moderate‐quality evidence; Analysis 3.2). Four studies comprising 169 participants examined the effects on sustained attention (Barker‐Collo 2009; Röhring 2004; Schottke 1997; Sturm 1991). As the heterogeneity between trials for this measure was high (I2 > 50%), we used a random‐effects model for analysing sustained attention (SMD 0.39, 95% CI –0.16 to 0.94; P = 0.16; low‐quality evidence; Analysis 3.3).
Rehabilitation of attention did not show any convincing effects on functional abilities in daily living (SMD 0.29, 95% CI –0.16 to 0.75; P = 0.21; 2 studies, 75 participants; very low‐quality evidence; Analysis 4.1; Röhring 2004; Schottke 1997), mood (SMD 0.01, 95% CI –0.36 to 0.39; P = 0.94; 3 studies using depression scales, 109 participants; low‐quality evidence; Analysis 4.2; Röhring 2004; Schottke 1997; Winkens 2009), or quality of life (SMD 0.02, 95% CI –0.37 to 0.40; P = 0.94; 2 studies, 103 participants; low‐quality evidence; Analysis 4.3; Barker‐Collo 2009; Winkens 2009).
Long‐term effects
Two studies comprising 99 participants assessed long‐term effects of treatment on divided attention and there was no convincing effect of treatment compared with care as usual (SMD 0.36, 95% CI –0.04 to 0.76; P = 0.08; very low‐quality evidence; Analysis 5.4; Barker‐Collo 2009; Winkens 2009). There was no convincing evidence for treatment effects on the other domains of attention. One study comprising 31 participants examined effects on alertness (SMD –0.26, 95% CI –0.97 to 0.45; P = 0.47; very low‐quality evidence; Analysis 5.1; Winkens 2009). Two studies comprising 99 participants investigated effects on selective attention at follow‐up (SMD 0.07, 95% CI –0.32 to 0.47; P = 0.72; very low‐quality evidence; Analysis 5.2; Barker‐Collo 2009; Winkens 2009), and one study comprising 66 participants assessed the effect on sustained attention (SMD 0.05, 95% CI –0.44 to 0.53; P = 0.84; very low‐quality evidence; Analysis 5.3; Barker‐Collo 2009).
The only study testing for long‐term effects on functional abilities in daily living comprising 66 participants found no evidence for an effect of treatment (SMD 0.02, 95% CI –0.46 to 0.51; P = 0.92; very low‐quality evidence; Analysis 6.1; Barker‐Collo 2009). Two studies with 99 participants found no convincing effects on mood (SMD 0.29, 95% CI –0.11 to 0.69; P = 0.15; very low‐quality evidence; Analysis 6.2) or quality of life (SMD 0.26, 95% CI –0.13 to 0.66; P = 0.19; very low‐quality evidence; Analysis 6.3) (Barker‐Collo 2009; Winkens 2009).
Subgroup and sensitivity analyses
We were unable to run subgroup or sensitivity analyses because there were insufficient data available.
Discussion
We found no new trials for this update. The results are unchanged from the previous review and are based on the data of six trials with 223 participants.
Summary of main results
There was no evidence to support a beneficial effect of cognitive rehabilitation on global attentional functions (very low‐quality evidence). People receiving cognitive rehabilitation showed improvements on measures of divided attention immediately after rehabilitation (moderate effect size, low‐quality evidence), but there was no convincing evidence that these improvements were retained (very low‐quality evidence). There was no evidence to support the effect of cognitive rehabilitation on specific attentional domains (alertness, selective attention, sustained attention), functional abilities, mood (depression), and quality of life.
Overall completeness and applicability of evidence
Some authors provided unpublished data (Barker‐Collo 2009; Röhring 2004; Winkens 2009), and others clarified aspects that were unclear from the published reports (Schottke 1997; Sturm 1991; Westerberg 2007). We excluded some studies on the basis of information from authors (Kim 2008), and others confirmed the results were not yet published (see Characteristics of studies awaiting classification table).
Trials generally had small sample sizes ranging from 18 to 78, which limits the ability to generalise from these studies. Future studies should be adequately powered to detect the effects of treatment on functional outcomes. The results from these studies should enable a power calculation for future studies.
The studies included a wide variety of interventions; almost all were computerised. The comparison for most studies was treatment as usual. Future studies could be improved by the use of attention placebo control groups that provide the computerised activities but not the attention retraining activities (e.g. as in Gray 1992). However, this may not be feasible in attentional rehabilitation studies where it is difficult to mask the nature of the intervention to the participants (e.g. in a group‐based intervention with a facilitator, where the objective or focus of the intervention may be clear to the participants).
Most studies assessed outcomes on measures of attention on standardised tests. The six studies reported 40 different test variables of attentional outcomes. It has been suggested that cognitive training for certain attentional domains might be more effective than for others (see Cappa 2005) and that there is limited generalisation of treatment from one attentional domain to another (Sturm 1997). Therefore, it seemed important to evaluate treatment effects on different attentional domains. However, it would be beneficial if there was broader consensus on the attentional processes these variables tap and greater consistency in the choice of outcome measures. A composite test score assessing several attentional domains would assist with identifying the overall benefit of attention training; however, there is no empirical framework or clear consensus on how to calculate an overall attention composite score (in the same way as, for example, an intelligence quotient (IQ) score). Future work towards a clear definition of attentional impairments and the best methods for measuring these will be needed for the field to progress.
Furthermore, as with cognitive rehabilitation research more broadly, few attention rehabilitation trials measured functional outcomes. Yet for stroke survivors, the impact of attentional impairments on activity and participation is the most meaningful target for change. Indeed, for many clinicians and researchers, this should be the logical endpoint or focus of cognitive rehabilitation. However, self‐report measures of everyday attentional difficulties also have the issue of demand characteristics on non‐blind participants who are reporting the outcome of the attentional training they know they have received. Measuring the everyday functional impact of attention interventions in valid, reliable and feasible ways (e.g. perhaps incorporating experience‐based sampling, close other/clinician reports, goal attainment scaling, or a combination of these) is another important challenge for this field of research.
The inclusion criteria for attentional deficits varied considerably across trials, and accordingly, the degree of attentional deficits at the start of the treatment differed widely. This review could not address whether treatment success is modulated by the severity of attentional impairments in an individual.
There were insufficient data to evaluate whether treatment is more effective in the postacute phase than in the acute phase of recovery (Cappa 2005; Cicerone 2011). Similarly, we were unable to conduct the planned subgroup analyses to determine whether outcomes varied according to frequency of intervention (number of sessions per week), intensity of intervention (total hours of intervention), and type of intervention because of insufficient data.
Quality of the evidence
The overall certainty of evidence was very low to moderate. The evidence base was small with few methodologically robust RCTs. We typically downgraded evidence because of imprecision due to small sample sizes and risk of bias due to inadequate reporting of allocation concealment and unclear risk of performance bias (see summary of findings Table for the main comparison and summary of findings Table 2).
Potential biases in the review process
Two review authors independently assessed the included studies and made final decisions following discussion. One review author (TL) proposed the allocation of attention tasks to attentional domains and the second review author of the last update (Nadina Lincoln) confirmed these. While the assignments are consistent with commonly used typologies and taxonomies of attentional processes in clinical settings, we acknowledge that these assignments are, to some degree, arbitrary as the same test variable may tap into several different attentional domains (Lezak 2004; Strauss 2006).
In addition, the exclusion of studies on attention retraining to improve single ADLs (e.g. driving ability), could be seen as a limitation, but outcomes based on individual ADLs would be difficult to aggregate. Based on our knowledge of the literature, we did not feel this was appropriate at this time, but perhaps could be considered when more research accrues. Excluding interventions that could have had an impact on cognition (e.g. music therapy or mindfulness) could have biased the outcomes, but our definition of cognitive rehabilitation and interventions to be considered as cognitive rehabilitation was established a priori. A future more generic review that focuses on all types of non‐pharmacological interventions for attentional problems could consider including these and other types of interventions that are likely to have a positive impact on attention (e.g. interventions targeting fatigue and sleep disturbances). Similarly, the selection requirement of demonstrable attention deficits and exclusion of studies which based the selection on impairments in general cognitive functioning (e.g. Mini‐Mental State Examination scores) could be considered as a somewhat narrow inclusion criterion. However, we felt it was important to only include studies of cognitive rehabilitation for attentional problems that recruited people who had attentional problems, because this may have affected the outcomes of the intervention. Future reviews could consider widening this inclusion criterion but would need to consider a sensitivity analysis to examine whether there are differential treatment effects between studies that do and do not include those with attentional problems at baseline.
Agreements and disagreements with other studies or reviews
We found some benefits of cognitive rehabilitation for divided attention, but not for other attentional domains. This finding is consistent with a meta‐analysis of attention rehabilitation after acquired brain injury, which also found effects confined to divided attention (Virk 2015). Other relevant meta‐analyses have tended to find a small effect for attention that was not specific to a particular domain (Bogdanova 2016; Rogers 2018; Weicker 2016); however, not all of these reviews analysed each domain separately.
Rogers 2018 further reported that improvements in attention were observed for interventions targeting visuo‐spatial and perceptual skills and general cognition as well those targeting attention. This suggests that a wider definition of attention rehabilitation may have produced different results for this review.
The review concludes that overall there is insufficient evidence to support or refute the effectiveness of cognitive rehabilitation for attention after stroke. This conclusion is unchanged from the previous Cochrane Review (Loetscher 2013), and consistent with another meta‐analysis assessing treatment outcomes of attention rehabilitation after acquired brain injury (Park 2001). The finding that short‐term gains in attention are not consistently maintained at longer‐term follow‐up was also reported in the meta‐analyses by Rogers 2018 and Virk 2015, supporting the need for evaluations of strategies to sustain gains made in cognitive rehabilitation.
The appraisal of the evidence in favour of rehabilitation is somewhat less positive than reviews of cognitive rehabilitation for people with acquired brain injury (Cappa 2005; Cicerone 2011; Cicerone 2019), as well as one review of non‐RCTs in stroke (Merriman 2019). One reason for the discrepancy is probably because the current review applied more rigorous inclusion criteria than these reviews. In Cicerone 2019, for example, seven of the 13 studies reviewed were class III studies. Consistent with this, Rogers 2018 found the strength of the overall effect of cognitive rehabilitation was moderated significantly by study quality, with lower quality studies reporting larger effect sizes.
Study flow diagram. CCT: controlled clinical trial; RCT: randomised controlled trial.
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
Comparison 1 Attention training versus control – impact on global measures of attention deficits immediately after treatment, Outcome 1 Subjective measures.
Comparison 2 Attention training versus control – impact on global measures of attention deficits at follow‐up , Outcome 1 Subjective measures at follow‐up.
Comparison 3 Attention training versus control – impact on attentional domains immediately after treatment, Outcome 1 Alertness.
Comparison 3 Attention training versus control – impact on attentional domains immediately after treatment, Outcome 2 Selective attention.
Comparison 3 Attention training versus control – impact on attentional domains immediately after treatment, Outcome 3 Sustained attention.
Comparison 3 Attention training versus control – impact on attentional domains immediately after treatment, Outcome 4 Divided attention.
Comparison 4 Attention training versus control – impact on functional abilities in daily living, mood, and quality of life immediately after treatment, Outcome 1 Functional abilities.
Comparison 4 Attention training versus control – impact on functional abilities in daily living, mood, and quality of life immediately after treatment, Outcome 2 Mood (depression).
Comparison 4 Attention training versus control – impact on functional abilities in daily living, mood, and quality of life immediately after treatment, Outcome 3 Quality of life.
Comparison 5 Attention training versus control – impact on attentional domains at follow‐up , Outcome 1 Alertness at follow‐up.
Comparison 5 Attention training versus control – impact on attentional domains at follow‐up , Outcome 2 Selective attention at follow‐up.
Comparison 5 Attention training versus control – impact on attentional domains at follow‐up , Outcome 3 Sustained attention at follow‐up.
Comparison 5 Attention training versus control – impact on attentional domains at follow‐up , Outcome 4 Divided attention at follow‐up.
Comparison 6 Attention training versus control – impact on functional abilities in daily living, mood, and quality of life at follow‐up, Outcome 1 Functional abilities at follow‐up.
Comparison 6 Attention training versus control – impact on functional abilities in daily living, mood, and quality of life at follow‐up, Outcome 2 Mood (depression) at follow‐up.
Comparison 6 Attention training versus control – impact on functional abilities in daily living, mood, and quality of life at follow‐up, Outcome 3 Quality of life at follow‐up.
| Attention training compared to control for attention deficits following stroke immediately after treatment | |||||
| Patient or population: people with attention deficits following stroke | |||||
| Outcomes | No of participants | Certainty of the evidence | Estimated effect of intervention (SMD)b | 95% confidence interval of estimated effect | Comments |
| Subjective measures – assessed with Cognitive Failures Questionnaire & Mental Slowness Questionnaire | 53 | ⊕⊝⊝⊝ | 0.53 SMDs better | 0.03 SMDs worse to 1.08 SMDs better | — |
| Objective global measures | No studies | — | — | — | No data |
| Alertness – assessed with TAP phasic alertness, Wiener Reaktionsgerat Visual RT, Simple RT & Tempo‐Lern Test | 136 | ⊕⊕⊝⊝ | 0.14 SMDs better | 0.20 SMDs worse to 0.48 SMDs better | — |
| Selective attention – assessed with TAP selective attention, Trail Making A, Zahlen‐Verbindungstest, Wiener Reaktionsgerat Choice RT, Ruff 2&7 | 223 | ⊕⊕⊕⊝ | 0.08 SMDs worse | 0.35 SMDs worse to 0.18 SMDs better | — |
| Sustained attention – assessed with IVA‐CPT Fullscale Attention Quotient, d2, Konzentrations‐Verlaufs‐Test, Wiener Vigilanzgerat | 169 | ⊕⊕⊝⊝ | 0.39 SMDs better | 0.16 SMDs worse to 0.94 SMDs better | — |
| Divided attention – assessed with TAP divided attention, PASAT | 165 | ⊕⊕⊝⊝ | 0.67 SMDs better | 0.35 SMDs to 0.98 SMDs better | — |
| Functional abilities – assessed with Barthel, Functional Independence Measure (FIM) | 75 | ⊕⊝⊝⊝ | 0.29 SMDs better | 0.16 SMDs worse to 0.75 SMDs better | — |
| Mood (depression) – assessed with Center for Epidemiologic Studies Depression Scale, Zung Depression Status Inventory, Emotional State Questionnaire (Depression subscale) | 109 | ⊕⊕⊝⊝ | 0.01 SMDs better | 0.36 SMDs worse to 0.39 SMDs better | — |
| Quality of life – assessed with SF‐36 (Mental Component Summary subscale), EQ‐VAS | 103 | ⊕⊕⊝⊝ | 0.02 SMDs better | 0.37 SMDs worse to 0.40 SMDs better | — |
| CI: confidence interval; IVA‐CPT: Integrated Visual and Auditory Continuous Performance Test; n: number of participants; PASAT: Paced Auditory Serial Addition Test; RCT: randomised controlled trial; ROB: risk of bias; RT: reaction time; SF‐36: 36‐item Short Form; SMD: standardised mean difference; TAP: Tests of Attentional Performance. | |||||
| GRADE Working Group grades of evidence | |||||
| aDowngraded for imprecision: two levels for 1–99 participants; one level for 100–199 participants; no downgrade > 199 participants. | |||||
| Attention training compared to control for attention deficits following stroke 3–6 months after treatment | |||||
| Patient or population: people with attention deficits following stroke | |||||
| Outcomes | No of participants | Certainty of the evidence | Estimated effect of intervention (SMD)b | 95% confidence interval of estimated effect | Comments |
| Subjective measures – assessed with Cognitive Failures Questionnaire & Mental Slowness Questionnaire | 99 | ⊕⊝⊝⊝ | 0.16 SMDs better | 0.23 SMDs worse to 0.56 SMDs better | — |
| Objective global measures | No studies | — | — | — | No data |
| Alertness – assessed with Simple RT | 31 | ⊕⊝⊝⊝ | 0.26 SMDs worse | 0.97 SMDs worse to 0.45 SMDs better | — |
| Selective attention – assessed with Trail Making A | 99 | ⊕⊝⊝⊝ | 0.07 SMDs better | 0.32 SMDs worse to 0.47 SMDs better | — |
| Sustained attention – assessed with IVA‐CPT Fullscale Attention Quotient | 66 | ⊕⊝⊝⊝ | 0.05 SMDs better | 0.44 SMDs worse to 0.53 SMDs better | — |
| Divided attention – assessed with PASAT | 99 | ⊕⊝⊝⊝ | 0.36 SMDs better | 0.04 SMDs to 0.76 SMDs better | — |
| Functional abilities – assessed with Modified Rankin | 66 | ⊕⊝⊝⊝ | 0.02 SMDs better | 0.46 SMDs worse to 0.51 SMDs better | — |
| Mood – assessed with Center for Epidemiologic Studies Depression Scale, General Health Questionnaire | 99 | ⊕⊝⊝⊝ | 0.29 SMDs better | 0.11 SMDs worse to 0.69 SMDs better | — |
| Quality of life – assessed with SF‐36 (Mental Component Summary subscale), EQ‐VAS | 99 | ⊕⊝⊝⊝ | 0.26 SMDs better | 0.13 SMDs worse to 0.66 SMDs better | — |
| CI: confidence interval; IVA‐CPT: Integrated Visual and Auditory Continuous Performance Test; PASAT: Paced Auditory Serial Addition Test; RCT: randomised controlled trial; ROB: risk of bias; RT: reaction time; SF‐36: 36‐item Short Form; SMD: standardised mean difference. | |||||
| GRADE Working Group grades of evidence | |||||
| aDowngrades for imprecision: two levels for 1–99 participants; one level for 100–199 participants; no downgrade > 199 participants. | |||||
| Study ID | Subjective global measure | Objective global measure | Alertness | Selective attention | Sustained attention | Divided attention |
| Cognitive Failures Questionnairea | — | — | Trail Making Ab | IVA‐CPT Full‐Scale Attention Quotientb | PASAT (2.4 sec ISI)b | |
| — | — | TAP phasic alertness | TAP selective attention | d2 (Hits‐Errors) | TAP divided attention | |
| — | — | Tempo‐Lern‐Test (1st block) | Zahlen‐Verbindungstest | Konzentrations‐Verlaufs‐Test (combined speed/errors scores) | — | |
| — | — | Wiener Reaktionsgerat Visual RT | Wiener Reaktionsgerat Choice RT | Wiener Vigilanzgerat (Hits) | — | |
| Cognitive Failures Questionnaire | — | — | Ruff 2&7 | — | PASAT (2.4 sec ISI) | |
| Mental Slowness Questionnaireb | — | Simple RTb | Trail Making A (time)b | — | PASAT (3.2 sec ISI)b | |
| aOnly measured at follow‐up, but not after treatment. ISI: interstimulus interval; IVA‐CPT: Integrated Visual and Auditory Continuous Performance Test; PASAT: Paced Auditory Serial Addition Test; RT: reaction time; TAP: Tests of Attentional Performance. | ||||||
| Study ID | Functional abilities | Mood | Quality of life |
| Modified Rankina | GHQa | SF‐36 (MCS subscale)b | |
| FIM | DSI | — | |
| Barthel | EMO‐D | — | |
| — | CES‐Db | EQ‐VASb | |
| aOnly measured at follow‐up, but not after treatment. CES‐D: Center for Epidemiologic Studies Depression Scale; DSI: Zung Depression Status Inventory; EMO‐D: Emotional State Questionnaire (Depression subscale); FIM: Functional Independence Measure; GHQ: General Health Questionnaire; MCS: Mental Component Summary; VAS: visual analogue scale. | |||
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1 Subjective measures Show forest plot | 2 | 53 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.53 [‐0.03, 1.08] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1 Subjective measures at follow‐up Show forest plot | 2 | 99 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.16 [‐0.23, 0.56] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1 Alertness Show forest plot | 4 | 136 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.14 [‐0.20, 0.48] |
| 2 Selective attention Show forest plot | 6 | 223 | Std. Mean Difference (IV, Fixed, 95% CI) | ‐0.08 [‐0.35, 0.18] |
| 3 Sustained attention Show forest plot | 4 | 169 | Std. Mean Difference (IV, Random, 95% CI) | 0.39 [‐0.16, 0.94] |
| 4 Divided attention Show forest plot | 4 | 165 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.67 [0.35, 0.98] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1 Functional abilities Show forest plot | 2 | 75 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.29 [‐0.16, 0.75] |
| 2 Mood (depression) Show forest plot | 3 | 109 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.01 [‐0.36, 0.39] |
| 3 Quality of life Show forest plot | 2 | 103 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.02 [‐0.37, 0.40] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1 Alertness at follow‐up Show forest plot | 1 | 31 | Std. Mean Difference (IV, Fixed, 95% CI) | ‐0.26 [‐0.97, 0.45] |
| 2 Selective attention at follow‐up Show forest plot | 2 | 99 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.07 [‐0.32, 0.47] |
| 3 Sustained attention at follow‐up Show forest plot | 1 | 66 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.05 [‐0.44, 0.53] |
| 4 Divided attention at follow‐up Show forest plot | 2 | 99 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.36 [‐0.04, 0.76] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1 Functional abilities at follow‐up Show forest plot | 1 | 66 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.02 [‐0.46, 0.51] |
| 2 Mood (depression) at follow‐up Show forest plot | 2 | 99 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.29 [‐0.11, 0.69] |
| 3 Quality of life at follow‐up Show forest plot | 2 | 99 | Std. Mean Difference (IV, Fixed, 95% CI) | 0.26 [‐0.13, 0.66] |
