Dance therapy for schizophrenia
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To evaluate the effects of dance therapy for people with schizophrenia or schizophrenia‐like illnesses compared with standard care and other interventions.
Background
Dance has been used as a healing ritual since the earliest recorded history, but the establishment of dance therapy as a profession is relatively recent (Chodorow 1991). Dance therapy is also sometimes referred to as dance movement therapy (DMT) (Payne 2006). It is informed by contemporary psychological and psychotherapeutic theories, body psychotherapy and multi‐cultural trends in dance (Payne 2006). According to the American Dance Therapy Association (ADTA), dance therapy can be used with people of all age, race or ethnic background in the forms of individual or group therapy. It is effective in the treatment of people with developmental, medical, social, physical and psychological impairments and can be practiced in various settings, such as mental health rehabilitation, medical, educational, forensic, nursing homes, day care, disease prevention and health promotion programs.
The American Dance Therapy Association (ADTA) defines dance therapy as 'the psychotherapeutic use of movement as a process which furthers the emotional, social, cognitive, and physical integration of the individual' (http://www.adta.org/about/factsheet.cfm). Payne 2006 notes that the principle of dance therapy is based on the assumption that motion and emotion are in reciprocal interaction. Through this relationship as a channel, one can embody a deeper connection with oneself. From a therapeutic point of view, there are a number of factors which make dance therapy particularly appropriate for use as therapeutic tool. Through body movement dance stimulates and releases feelings, enables the person to release communications and contact non‐verbally, reduces anxiety through the non‐critical therapeutic setting, free movements with rhythm together creates joy both physically and emotionally and human's natural responses to rhythm promotes both individual movement and participatory behaviour of a group (Espenak 1981). From a technical point of view, the foundations of dance therapy are, 'the physical phenomena that provoke the occurrence of the emotion'. The therapist learns to interpret client's motor expression and to relate personal movements to personal feelings, and to reach the feeling through opportunities for experience in movement.
However, there is no special therapeutic dance; dance only becomes therapeutic in the hands of a specialist or a therapist (Exiner 1994). Therapeutic dance in any situation or with any population involves thinking, feeling and willing. The treatment approach is individualised, for example, duration of treatment sessions can vary from 20 minutes to 90 minutes depending on the individual client's frustration and tolerance levels. According to Exiner 1994 the model of a dance therapy session commonly involves the following phases: entry, exploration, core action, review and conclusion. Participants warm up at entry stage and prepare their body for action. Then the movements which arise during entry phase are experimented within the exploration phase. Some of the physically beneficial and emotionally significant movements are then selected to be taken through to the core action phase and become themes. Movements are refined at core action phase and close attention is paid to its psycho‐physical contents. Recognition of further therapeutic steps is also developed through this process. Before concluding the sessions, a review of the material is usually arranged. Therapist and patient's decide together what would be valuable for them to take away.
Objectives
To evaluate the effects of dance therapy for people with schizophrenia or schizophrenia‐like illnesses compared with standard care and other interventions.
Methods
Criteria for considering studies for this review
Types of studies
We included randomised controlled trials. Where a trial was described as 'double‐blind', but it was only implied that the study was randomised, we included these trials in a sensitivity analysis. If there was no substantive difference within primary outcomes (see types of outcome measures) when these 'implied randomisation' studies were added, then we included these in the final analysis. If there was a substantive difference, we only used clearly randomised trials and described the results of the sensitivity analysis in the text. We excluded quasi‐randomised studies, such as those allocating by using alternate days of the week.
Types of participants
We included people with schizophrenia or where the majority (80%) of people in the study are likely to suffer from schizophrenia. In studies where non‐specific labels were used, such as "chronic serious mental illness" we assumed that most people suffered from schizophrenia. We were not concerned how the diagnosis was made and included trials diagnosing people by any criteria, irrespective of gender, age or nationality.
Types of interventions
1. Dance Therapy
Dance therapy (in groups or individually), for any length of time, as an adjunctive treatment for schizophrenia or schizophrenia‐like disorders, regardless of the other interventions being used (any biological, psychological or social intervention). We employed The American Dance Therapy Association's (ADTA) definition of dance therapy as a standard for inclusion, 'the psychotherapeutic use of movement as a process which furthers the emotional, social, cognitive and physical integration of the individual'. Regardless of whether it was formally stated as dance therapy in the paper, we considered any intervention using dance or movement or any similar approaches.
2. Standard/routine care
This includes care that a person with schizophrenia would normally receive had they not been included in the research trial. This also includes 'waiting list control groups'.
3. Other treatments
This would include any other biological, psychological or social treatments such as medication, problem solving therapy (Xia 2007) , psychoeducation (Pekkala 2002), cognitive behavioural therapy (Jones 2004), family intervention (Pharoah 2006) or psychodynamic psychotherapy (Malmberg 2001).
4. Non intervention
Untreated control groups.
Types of outcome measures
1. Service utilisation
1.1 Days in hospital*
1.2 Hospital admission
2. Clinical global response
2.1 Relapse*
2.2 Global state ‐ not improved
2.3 Average change or endpoint score in global state
2.4 Leaving the study early
2.5 Compliance with medication
3. Mental state and behaviour
3.1 Positive symptoms (delusions, hallucinations, disordered thinking)
3.2 Negative symptoms (avolition, poor self‐care, blunted affect)
3.3 No clinically important change in specific symptoms
3.4 Average change or endpoint score
4. Social functioning
4.1 Average change or endpoint scores
4.2 Social impairment
4.3 Employment status (employed/unemployed)
4.4 Work related activities
4.5 Unable to live independently
5. Quality of life
5.1 No clinically important change in quality of life
5.2 Not any change in quality of life
5.3 Average change or endpoint scores
5.4 No clinically important change in specific aspects of quality of life
5.5 Not any change in specific aspects of quality of life
6. Family outcome
6.1 Average score/change in family burden
6.2 Patient and family coping abilities
6.3 Understanding of the family member with schizophrenia
6.4 Family care and maltreatment of the person with schizophrenia
6.5 Expressed emotion
6.6 Quality of life/satisfaction with care for either recipients of care or their carers
6.7 Economic outcomes
6.8 Cost of care
7. Satisfaction with treatment
7.1 Recipient of treatment not satisfied with therapy
7.2 Recipient of treatment average satisfaction score
7.3 Recipient of treatment average change in satisfaction scores
7.4 Carer not satisfied with treatment
7.5 Carer average satisfaction score
7.6 Carer average change in satisfaction score
8. Adverse effects/events
8.1 No clinically important general adverse effects
8.2 Not any general adverse effects
8.3 Average change or endpoint general adverse effect scores
8.4 No clinically important change in specific adverse effect
8.5 Not any change in specific adverse effects
8.6 Average change or endpoint specific adverse effects
8.7 Suicide and all causes of mortality
* We choose days in hospital and relapse as our pre‐stated primary outcomes.
We divided outcomes into short term (less than one month) medium term (one month ‐ three months) and long term (more than three months).
Search methods for identification of studies
1. Electronic searches
We searched the Cochrane Schizophrenia Group Trials Register (July 2007) using the phrase:
[(* danc* in title, abstract, index terms of REFERENCE) or (danc* in interventions of STUDY)]
This register is compiled by systematic searches of major databases, hand searches and conference proceedings (see Group Module).
2. Reference searching
We inspected references of all identified studies (included and excluded) for further relevant trials.
3. Personal contact
We contacted the first authors of all included studies for information regarding unpublished trials and further data on the published trials.
Data collection and analysis
1. Selection of trials
We independently inspected citations identified in the search. After identifying potentially relevant abstracts we ordered full papers. TG re‐inspected a random 10% to ensure reliable selection. Once the full papers had been obtained JX and TG decided if they met the review inclusion criteria. We sought to resolve disputes over whether studies met the inclusion criteria by discussion, but if agreement could not be reached these trials were added to the 'awaiting assessment' list until further information became available.
2. Assessment of methodological quality
We assessed the methodological quality of included trials in this review using the criteria described in the Cochrane Handbook (Higgins 2006) and the Jadad Scale (Jadad 1996). The former is based on the evidence of a strong relationship between allocation concealment and direction of effect (Schulz 1995). The categories are defined below:
A. Low risk of bias (adequate allocation concealment)
B. Moderated risk of bias (unclear allocation concealment)
C. High risk of bias (inadequate concealment).
For the purpose of the analysis, we only included trials that met the Cochrane Handbook criteria A or B.
The Jadad scale measures a wider range of factors that impact on the quality of a trial. The scale includes three items:
1. Was the study described as randomised?
2. Was the study described as double‐blind?
3. Was there a description of withdrawals and drop outs?
Each item receives one point if the answer is positive. In addition, a point can be deducted if either the randomisation or the blinding/masking procedures described are inadequate or unclear. For this review we used a cut‐off of two points on the Jadad Scale to check the assessment made by the Cochrane Handbook criteria. The Jadad Scale, however, was not used to exclude trials.
3. Data collection
We (JX, TG) extracted data from selected trials independently. JX carried out a separate re‐extraction of data to ensure reliability. Again, when disputes arose, we attempted to resolve these by discussion and where further clarification was needed we contacted the authors of trials for further information. While awaiting further information, trials were added to the list of those awaiting assessment.
4. Data synthesis
4.1 Data types
We assessed outcomes using continuous (for example changes on a behaviour scale), categorical (for example, one of three categories on a behaviour scale, such as "little change", "moderate change" or "much change") or dichotomous (for example, either "no important changes or "important change" in a person's behaviour) measures. Currently RevMan does not support categorical data so we were unable to analyse this.
4.2 Incomplete data
We planned not to include trial outcomes if more than 30% of participants in any group were not reported in the final analysis. We carried out an intention to treat analysis. On the condition that more than 70% of people completed the study, everyone allocated to the intervention was counted whether they completed the follow up or not. It was assumed that those who dropped out had the negative outcome, with the exception of death. Where trials with high attrition were found, we analysed the impact of excluding studies with high attrition rates (>30%) in a sensitivity analysis for primary outcomes. If exclusion of data from this latter group resulted in a substantive change in estimates of effect, we reported this.
4.3 Dichotomous data
Where possible, efforts were made to convert outcome measures to dichotomous data. This can be done by identifying cut off points on rating scales and dividing participants accordingly into "clinically improved" or "not clinically improved". It was generally assumed that if there had been a 50% reduction in a scale‐derived score such as the Brief Psychiatric Rating Scale (BPRS, Overall 1962) or the Positive and Negative Syndrome Scale (PANSS, Kay 1986), this could be considered as a clinically significant response (Leucht 2005a, Leucht 2005b). If data based on these thresholds were not available, we used the primary cut‐off presented by the original authors.
We calculated the relative risk (RR) and its 95% confidence interval (CI) based on the random effects model, as this takes into account any differences between studies even if there is no statistically significant heterogeneity. It has been shown that RR is more intuitive (Boissel 1999) than odds ratios, and that odds ratios tend to be interpreted as RR by clinicians (Deeks 2000). This misinterpretation then leads to an overestimate of the impression of the effect. When the overall results were significant we calculated the number needed to treat (NNT) and the number needed to harm (NNH) as the inverse of the risk difference.
4.4 Continuous data
4.4.1 Normal distribution
Continuous data on outcomes in trials relevant to mental health issues are often not normally distributed. To avoid the pitfall of applying parametric tests to non‐parametric data we applied the following standards to continuous final value endpoint data before inclusion: (a) standard deviations and means were reported in the paper or were obtainable from the authors; (b) when a scale started from zero, the standard deviation, when multiplied by two, should be less than the mean (otherwise the mean is unlikely to be an appropriate measure of the centre of the distribution ‐ Altman 1996); In cases with data that are greater than the mean they were entered into 'Other data' table as skewed data. If a scale starts from a positive value (such as PANSS, which can have values from 30 to 210) the calculation described above in (b) should be modified to take the scale starting point into account. In these cases skewness is present if 2SD>(S‐Smin), where S is the mean score and Smin is the minimum score. We reported non‐normally distributed data (skewed) in the 'other data types' tables.
For change data (mean change from baseline on a rating scale) it is impossible to tell whether data are non‐normally distributed (skewed) or not, unless individual patient data are available. After consulting the ALLSTAT electronic statistics mailing list, we entered change data in RevMan analyses and reported the finding in the text to summarise available information. In doing this, we assumed either that data were not skewed or that the analysis could cope with the unknown degree of skew.
4.4.2 Final endpoint value versus change data
Where both final endpoint data and change data were available for the same outcome category, only final endpoint data were presented. We acknowledge that by doing this much of the published change data may be excluded, but argue that endpoint data is more clinically relevant and that if change data were to be presented along with endpoint data, it would be given undeserved equal prominence. Where studies reported only change data we contacted authors for endpoint figures.
4.4.3 Data synthesis
For continuous outcomes we estimated a weighted mean difference (WMD) between groups based on a random effects model, as this takes into account any differences between studies even if there is no statistically significant heterogeneity.
4.5 Rating scales: A wide range of instruments are available to measure mental health outcomes. These instruments vary in quality and many are not valid, or even ad hoc. For outcome instruments some minimum standards have to be set. It has been shown that the use of rating scales which have not been described in a peer‐reviewed journal (Marshall 2000) are associated with bias, therefore the results of such scales were excluded. Furthermore, we stipulated that the instrument could be considered a global assessment of an area of functioning. It was expected, however, that the therapists would also frequently be the rater, such data were included but commented on as 'prone to bias'.
Whenever possible we took the opportunity to make direct comparisons between trials that used the same measurement instrument to quantify specific outcomes. Where continuous data were presented from different scales rating the same effect, we presented both sets of data and inspected the general direction of effect.
4.6 Cluster trials
Studies increasingly employ cluster randomisation (such as randomisation by clinician or practice) but analysis and pooling of clustered data poses problems. Firstly, authors often fail to account for intra class correlation in clustered studies, leading to a unit‐of‐analysis error (Divine 1992) whereby p values are spuriously low, confidence intervals unduly narrow and statistical significance overestimated. This causes Type I errors (Bland 1997, Gulliford 1999).
Where clustering was not accounted for in primary studies, we presented the data in a table, with a (*) symbol to indicate the presence of a probable unit of analysis error. In subsequent versions of this review we will seek to contact first authors of studies to obtain intra‐class correlation co‐efficients of their clustered data and to adjust for this using accepted methods (Gulliford 1999). Where clustering has been incorporated into the analysis of primary studies, we will also present these data as if from a non‐cluster randomised study, but adjusted for the clustering effect.
We have sought statistical advice and have been advised that the binary data as presented in a report should be divided by a design effect. This is calculated using the mean number of participants per cluster (m) and the intraclass correlation co‐efficient (ICC) [Design effect=1+(m‐1)*ICC] (Donner 2002). If the ICC was not reported it was assumed to be 0.1 (Ukoumunne 1999). If cluster studies had been appropriately analysed taking into account intra‐class correlation coefficients and relevant data documented in the report, we synthesised these with other studies using the generic inverse variance technique.
5. Investigation for heterogeneity
We considered all the included studies within any comparison to judge for clinical heterogeneity. Then we visually inspected graphs to investigate the possibility of statistical heterogeneity. We supplemented this by using primarily the I‐squared statistic. This provides an estimate of the percentage of variability due to heterogeneity rather than chance alone. Where the I‐squared estimate was greater than or equal to 50%, we interpreted this as indicating the presence of considerable levels of heterogeneity (Higgins 2003). Where heterogeneity was present, we investigated reasons for this. If it substantially altered the results, we did not summate data, but presented the data separately and investigated reasons for heterogeneity.
6. Addressing publication bias
Where possible, we entered data from all identified and selected trials into a funnel graph (trial effect versus trial size) in an attempt to investigate the likelihood of overt publication bias (Egger 1997).
7. Sensitivity analyses
Where possible we analysed the effect of including studies with high attrition in a sensitivity analysis, according to our pre‐stated primary outcomes (days in hospital and relapse). Also, where possible we analysed primary outcomes in trials where randomisation was implied (rather than described), with trials that clearly described the use of random allocation.
8. General
Where possible, we entered data in such a way that the area to the left of the line of no effect indicated a favourable outcome for problem solving skills therapy.
