Sensory environment on health‐related outcomes of hospital patients
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To assess the effect of the sensory hospital environment on adult patient health‐related outcomes.
Background
The International Academy for Design and Health held its Third World Congress in 2003, highlighting the growing multinational interest on environmental design that promotes health (Dilani 2004). A reform on a global scale is underway to make hospitals much more than places to go and receive treatment; hospitals are now being conceptualised as places that have the potential to positively impact health through being restorative, healing environments (Dilani 2001). The World Health Organisation (WHO) highlights the important role of the environment in the health process, and calls for action towards creating supportive environments ('Ottowa' 2004). In accordance with this movement, international organisations such as The Centre for Health Design (CHD) have been established to serve a network of more than 25,000 professionals worldwide ('CHD' 2003). CHD's mission is to advocate 'healing environments' by demonstrating the value of evidence‐based design in improving health and quality of life.
Other initiatives have been stimulated by the US‐based Society for the Arts in Healthcare ('SAH' 2003), which attempts to demonstrate the value the arts can play in the healing process, and the UK‐based Medical Architecture Research Unit (Etheridge 2004), which provides research consultancy and training with a vision to explore the effects of the built environment on health outcomes. Research into, and implementation of healing healthcare environments is also being carried out in Japan (Cooper 2002; Takayanagi 2004), and across Europe (Pelican 2001).
In the Middle East various major investment projects are supporting a rapid growth in the hospital sector (News 2004) and the hospital industry in the United States is going through a major building boom with billions more dollars being spent on replacing or renovating old facilities (Babwin 2002). In the United Kingdom, the Private Finance Initiative (PFI) has prompted a renewed interest in hospital design, investing billions of pounds into the biggest new hospital building programme in the history of the NHS (Milburn 2001). Investments such as these have provided an opportunity for hospitals to be considered as 'therapeutic environments' (Gesler 2004), spurring on initiatives such as the UK‐based scheme in which the Kings Fund and NHS Estates are offering grants to health authorities to enhance the healing environment (Neuberger 2003).
Some argue that this expenditure is a waste of resources (Lipley 2001), whilst others have highlighted the lack of 'evidence‐based practice' when it comes to hospital design (Frumkin 2003). Schemes set up to enhance the hospital environment are often not evaluated on the grounds that it is too logistically complex (Comer 1982), or by simply stating that the effects are obvious (Parker 2000). There is some empirical evidence in support of creating healing environments in care facilities however, and researchers are finding that changes to the physical environment can positively influence patient outcomes (Devlin 2003; Rubin 1996). In a recent invitation‐only conference entitled 'Designing the 21st Century Hospital: serving patients and staff', held by the Robert Wood Johnson Foundation ('Webcast' 2004), Craig Zimring and Roger Ulrich referred to a literature review they have recently conducted, finding over 600 studies on the effects of the hospital environment on patients, families and staff (Ulrich 2004a). In their presentation of the research Zimring and Ulrich emphasised the evidence mainly in terms of quantity and consistency of findings. Following the presentations, delegates discussed the value of applying quality criteria to current evidence, just as in a Cochrane review.
The environment can be altered in endless ways. Some environmental changes may be detrimental to health (Thompson 2000), further exemplifying the need for using evidence‐based design. As a framework for assessing the evidence on 'healing design', the literature could be considered in terms of whether it regards: (1) aspects that are added to the environment as positive distracters (such as art and music); (2) aspects of the environment that are changed to reduce stressors (such as light, noise or air quality); and (3) providing the patient with access to nature (window views, hospital gardens, atriums). This third category is considered unique as nature is often (though disputably; Frumkin 2003) theorised as special for being inherently restorative (Ulrich 1993).
'Healing environments' are being advocated on a number of grounds: such as their ability to reduce anxiety, lower blood pressure, improve postoperative course, reduce the need for pain medication, and shorten the hospital stay (Ulrich 1992); good design has also been implicated to improve quality of sleep (Hewitt 2002; Marberry 2002), reduce hospital acquired infections (Ulrich 2004b), and improve staff retention and well‐being (Gross 1998; Marberry 2002; Neuberger 2003). Clearly this is a broad and complex area of study, with the 'environment' normally being a controlled variable, now being considered to influence all manner of outcomes; nevertheless, it is imperative that the evidence‐base for healing environments is assessed systematically, in order that time and money is not wasted, and most importantly, that patients are provided with the best possible opportunity to recover and be well.
Objectives
To assess the effect of the sensory hospital environment on adult patient health‐related outcomes.
Methods
Criteria for considering studies for this review
Types of studies
In this area of research it may often be very difficult to conduct a Randomised Controlled Trial (RCT) due to the nature of the intervention and logistical complexities. Hence this review will include a variety of study designs: RCTs, Controlled Clinical Trials (CCTs), Interrupted Time Series (ITS), and Controlled Before and After studies (CBAs).
Types of participants
The review will include adults attending hospital as patients. Studies will be included if over 90% of the participants are over 18. Both elective and non‐elective patients will be included in the review; these include adults that are admitted as in‐patients as well as those attending hospital as day‐patients or outpatients. We shall include psychiatric patients since the concept that the environment is integral to the healing process is seen as especially salient in psychiatric units (Gross 1998).
Types of interventions
The review will incorporate studies that investigate any aspect(s) of the sensory environment. Interventions may be those that alter the environment by one or a mixture of the following ways:
(1) Providing positive distracters to compliment the treatment already being administered. Positive distracters are elements of the sensory environment; they do not include alternative therapies, which are received instead of orthodox treatments. Participants may be offered a choice of distraction but we will not include instances when participants are actively involved in creating a distraction (for example, creating a work of art). Positive distracters include:
* Viewing artwork (comparing different styles/patient choice of art versus no art)
* Viewing performance art (versus none)
* Music (comparing different styles/patient choice of music versus no music)
* Decoration (colour of walls etc.)
* Scents (different scents/patient choice of scent versus none)
* Television/video (absent versus present/differences between content/patient choice)
(2) Reducing environmental stressors by implementing physical changes. This does not include changes that are made to policy (for example ensuring multi‐bed rooms are unisex). Physical changes to the sensory environment include:
* Noise reducing aids (e.g. sound‐absorbing ceiling tiles versus regular)
* Way‐finding aids (e.g. colour‐zoned areas, landmarks)
* Patient controls (e.g. access to lighting and ventilation controls)
* Lighting (e.g. natural versus fluorescent)
* People/privacy (e.g. open versus closed wards, decentralised nurse stations)
(3) Providing access to nature, including:
* Atriums (versus no atrium)
* Gardens (versus no garden/urban outdoor retreat)
* Window views (nature versus urban/other)
* Indoor planting (versus none)
Some studies may manipulate many variables and as such span across these three broad categories of environmental interventions (such as when a whole ward is redesigned Leather 2003), these studies will be included in the review provided they are not confounded with non‐environmental changes, such as changes to policy.
Studies will be excluded from the review if the intervention is not clearly defined (to the extent that it could be replicated). In order to meet this requirement studies should, where applicable, either:
* Provide the manufacturing details of the intervention being assessed, if appropriate;
* Provide pictures or diagrams, if appropriate;
* Provide a detailed description of the objective properties of the intervention, (e.g. an intervention of colour change needs to describe the specific hue; simply stating 'blue' is not specific enough).
* Provide a port of call from which more detailed information can be sought (if information in the article is not in depth enough).
All studies must be carried out in a hospital setting. Studies may be conducted in any area of the hospital grounds, such as general wards, specialist wards (e.g. Intensive Care Units), waiting rooms, common areas, and gardens. A hospital is defined (Ward 2004) as a health facility that:
* Provides communal care where there is an expectation that this care is time limited;
* Provides overnight accommodation;
* Provides nursing and personal care;
* Provides for people with illness and disability.
This definition includes hospices.
Types of outcome measures
Outcomes of interest include validated measures of anxiety; pain; length of hospital stay; patients' satisfaction and opinions; quality of sleep; aggression and mood; and hospital acquired infections. We will not consider length of hospital stay as applicable to studies conducted in hospices. We are including a broad range of outcomes since the environment may affect many aspects of a patient's physical and psychological health and different interventions may be applicable to some outcomes and not others.
Search methods for identification of studies
We will search electronic and non‐electronic sources.
We will search databases covering the fields of health, medicine, psychology and architecture. In addition, we will search the Cochrane Effective Practice and Organisation of Care Group (EPOC) specialised register along with the EPOC pending database.
To identify possible additional studies, we have developed a strategy for MEDLINE using relevant MeSH terms and text words that have not been used in the EPOC MEDLINE search strategy. This strategy will be adapted for other databases that we plan to search. These include the Cochrane Central Register of Controlled Trials; EMBASE; British Nursing Index (BNI); PsychInfo; Construction and Building Abstracts (CBA); RIBA library online catalogue; InformeDesign; NHS Estates Knowledge and Information Portal; Avery; Building Services Research and Information Association (BSRIA); Chartered Institution of Building Services Engineers (CIBSE); Cumulative Index to Nursing and Allied Health Literature (Cinahl); Web of Knowledge; Best Evidence; Applied Social Sciences Index and Abstracts (ASSIA); System for Information on Grey Literature (Sigle); UK National Research Registers Project Index; Architecture Publication Index; TRIP; and Zetoc.
MEDLINE search strategy:
1.exp ART/
2.COLOR/
3.exp SENSORY‐ART‐THERAPIES/
4.exp PHYSICAL‐THERAPY‐TECHNIQUES/
5.television
6.MUSIC/
7.exp SENSATION/
8.distraction
9.or/1‐8
10.exp ARCHITECTURE/
11.healing design?
12.therapeutic design?
13.restorative design?
14.healing environment?
15.therapeutic environment?
16.restorative environment?
17.ENVIRONMENT‐DESIGN/
18.exp FACILITY‐DESIGN‐AND‐CONSTRUCTION
19.exp HEALTH‐FACILITY‐ENVIRONMENT/
20.HOLISTIC HEALTH/
21.exp ENVIRONMENT‐CONTROLLED/
22.exp DELIVERY‐OF‐HEALTH‐CARE/
23.PATIENT‐CENTRED‐CARE/
24.exp MIND‐BODY‐RELAXATION‐TECHNIQUES/
25.natural light*
26.fluorescent light*
27.temperature near room
28.exp SOUND/
29.exp SOCIOENVIRONMENTAL‐THERAPY/
30.or/10‐29
31.ECOLOGY/
32.CONSERVATION‐OF‐NATURAL‐RESOURCES/
33.exp ENVIRONMENTAL‐HEALTH/
34.nature near view?
35.nature near access
36.(garden*) not ((garden* in AU) or (garden* in AD))
37.window*
38.plant?
39.sanctuary
40.horticultur*
41.landscape?
42.urban
43.flower?
44.retreat
45.refuge
46.biophilia
47.flora?
48.or/31‐47
49.9 or 30 or 48
50.exp HOSPITALIZATION/
51.exp PSYCHOPHYSIOLOGY/
52.exp PHYSIOLOGY/
53.exp HEMODYNAMIC‐PHENOMENA/
54.exp ANALGESICS/
55.anxiety
56.stress
57.heart rate
58.blood pressure
59.exp PAIN/
60.pain
61.cortisol
62.physiological
63.analgesi*
64.anaesthe*
65.length near stay
66.recovery near time
67.days near recovery
68.PATIENT SATISFACTION/
69.exp EMOTIONS/
70.exp AGGRESSION/
71.SLEEP DEPRIVATION/
72.hospital acquired infection?
73.hospital associated infection?
74.or/50‐73
75.HUMAN in TG/
76.49 and 74 and 75
We will also search reference lists of relevant articles and handsearch relevant journals. We will contact relevant organisations (e.g. NHS Estates, CHD) and subject area experts.
Data collection and analysis
Selection of studies
One reviewer (AD) will carry out the initial search. Two reviewers (AD/RS/DW/TD/EG) will independently screen the studies obtained from the initial search. Each title will be rated as 'hit' (maybe eligible), 'unsure' (probably not eligible) or 'reject' (not to be assessed further). Any disagreement with regard to eligibility will be resolved through discussion between reviewers. Full text (English and non‐English) papers will be obtained for the 'hits' and abstracts for the 'unsures'.
Quality
Retrieved studies will be evaluated for methodological quality and appropriateness by at least two reviewers (AD/RS/DW/TD/EG), using criteria described in the EPOC module (see 'additional information, assessment of methodological quality' under 'group details'). For studies where there is difference of opinion a consensus will be reached through discussion between reviewers.
Data extraction
Two reviewers will undertake data extraction independently using a modified version of the EPOC data collection checklist. Any disagreements will be resolved through discussion between reviewers.
Data analysis
The results section will be structured by intervention with multi‐intervention studies (for example, whole ward redesign) being grouped as a separate category. Outcomes for individual interventions will be looked at in turn and the heterogeneity of the studies will be explored.
For continuous variables, we will use a weighted mean difference (WMD) for identical measures, or standardized mean difference (SMD), where different techniques were used to measure the same outcome domain, and we will calculate 95% confidence intervals (CI) for each study. For dichotomous variables, we will calculate an odds ratio (OR) and relative risk (RR) with 95% confidence intervals (95% CI) as appropriate.
Where statistical analyses are inappropriate or unfeasible, we will present a discursive account of the results with supporting tables. If it is appropriate to combine the studies, then we will use a random effects analysis. If there is evidence that the data are skewed, then we will present these data in tables only. We will present continuous data that are reported using medians and ranges in tables only.
We will consider the presence of heterogeneity qualitatively (based on the characteristics listed below), by visually examining forest plots (if there are sufficient numbers of comparisons for similar outcomes within each intervention) and using the chi squared test for heterogeneity using a 5% level of statistical significance. Where the numbers of studies permit, we will supplement these analyses with a meta‐regression to examine how the size of the observed effects are related to the following characteristics of the studies:
* Quality of study;
* Case mix (psychiatric/non‐psychiatric; over and under 65 year olds; condition);
* Hospital visit characteristics (in‐patient/out‐patient/day‐patient; type/area of hospital studied);
* Geography (countries in which studies were undertaken).
In considering the case mix, attention will be paid to psychiatric illness and the age of patients. Psychiatric patients will be classed as such if their psychological state leads to emotional or behavioural problems serious enough for them to require psychiatric intervention. Where possible, the data from studies that have included both psychiatric and non‐psychiatric patients will be divided up accordingly. Studies where 10 to 89% of participants have known psychiatric problems and cannot be analysed separately will be excluded from any meta‐regression. Studies will be included in the psychiatric category if 90% or more of participants are receiving a psychiatric intervention. If fewer than 10% of participants are classified as psychiatric, then the study will be classed as non‐psychiatric. Patients will be classified as above and below 65 years old in the same fashion. Depending on the results of the search, further consideration will be paid to other medical conditions and their severity.
If possible, studies will be characterised by the type of hospital visit, using 90% as a cut‐off point as outlined above. In‐patients are classed as those that require a hospital bed and require an overnight stay for tests or surgery; day‐patients are patients that require a hospital bed for specialised observation or health care for a limited number of hours of the day, but do not need to stay overnight; outpatients are people who are referred to see a hospital consultant for a specialist opinion or examination and do not require a hospital bed.
If settings are ambiguous as to whether they fit the definition of a hospital, and a decision cannot be reached through contact with the authors or venues themselves, then, where possible, a sensitivity analysis will be conducted with these ambiguous studies included and excluded from the results.
