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Introduction some reviews may have been limited by journal guidelines. Mental health laws in many countries limit involuntary hospital admissions to patients who Evidence was graded using the Grading of meet an obligatory dangerousness criterion Recommendations Assessment, Development (ODC) for risk to themselves or others. This and Evaluation (GRADE) Working Group policy approach is in use throughout Australia, approach where high quality evidence such as the USA, and some areas of Canada and that gained from randomised controlled trials Europe. Alternative criteria implemented in the (RCTs) may be downgraded to moderate or low UK and other parts of Canada and Europe if review and study quality is limited, if there is allow involuntary treatment in the absence of inconsistency in results, indirect comparisons, dangerousness, on the grounds of an assessed imprecise or sparse data and high probability of need for treatment if the patient is deemed reporting bias. It may also be downgraded if unable to give consent. risks associated with the intervention or other matter under review are high. Conversely, low Method quality evidence such as that gained from We have included only systematic reviews observational studies may be upgraded if effect (systematic literature search, detailed sizes are large, there is a dose dependent methodology with inclusion/exclusion criteria) response or if results are reasonably published in full text, in English, from the year consistent, precise and direct with low 2000 that report results separately for people associated risks (see end of table for an with a diagnosis of schizophrenia and related explanation of these terms)3. The resulting disorders. Reviews were identified by searching table represents an objective summary of the the databases MEDLINE, EMBASE, CINAHL, available evidence, although the conclusions Current Contents, PsycINFO and the Cochrane are solely the opinion of staff of NeuRA library. Hand searching reference lists of (Neuroscience Research Australia). identified reviews was also conducted. When
multiple copies of reviews were found, only the most recent version was included. Results Review reporting assessment was guided by the Preferred Reporting Items for Systematic We found one systematic review that met our Reviews and Meta-Analyses (PRISMA) inclusion criteria1. checklist that describes a preferred way to • Moderate to high quality evidence indicates 2 present a meta-analysis . Reviews with less that a requirement for patients to satisfy an than 50% of items checked have been obligatory ‘dangerousness’ criterion to allow excluded from the library. The PRISMA flow compulsory treatment may be associated diagram is a suggested way of providing with a longer duration of untreated psychosis information about studies included and in those regions. excluded with reasons for exclusion. Where no flow diagram has been presented by individual reviews, but identified studies have been described in the text, reviews have been checked for this item. Note that early reviews may have been guided by less stringent reporting checklists than the PRISMA, and that
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Large MM, Nielssen O, Ryan CJ, Hayes R Mental health laws that require dangerousness for involuntary admission may delay the initial treatment of schizophrenia
Social Psychiatry and Psychiatric Epidemiology 2008; 43(3): 251-256 View review abstract online
Comparison Duration of untreated psychosis in countries with and without obligatory dangerousness criterion for involuntary treatment.
Summary of evidence Moderate to high quality evidence (large samples, unable to assess consistency, precise, direct) indicates longer DUP is associated with a requirement for patients to fill obligatory dangerousness criteria before compulsory admission. Authors conclude that it is likely that at least some of the increase in DUP in regions with an obligatory dangerousness criterion is a direct result of differences in mental health law.
Duration of untreated psychosis (DUP)
47 studies, N = 5,849 The mean DUP in samples from regions with an obligatory dangerousness criterion (ODC) was significantly longer than regions without an ODC. Median values were not significantly different. Obligatory dangerousness criterion: Mean 79.5 weeks (95% CI 63.5 to 95.4), weighted mean 77.7 weeks Average median DUP in ODC: 27.5 weeks (95% CI 17.3 to 37.3 weeks), median 28 weeks No- obligatory dangerousness criterion: Mean 55.6 weeks (95% CI 43.4 to 68.8 weeks), weighted mean 55.7 weeks Average median DUP in non-ODC: 19.9 weeks (95% CI 12.9 to 26.9 weeks), median 16 weeks
Consistency in results Unable to assess; no measure of consistency is reported.
Precision in results Precise
Directness of results Direct
Explanation of acronyms
CI = Confidence Interval, DUP = Duration of Untreated Psychosis, ODC = Obligatory Dangerousness Criterion
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Explanation of technical terms Prevalence refers to how many existing cases there are at a particular point in time. * Bias has the potential to affect reviews of Incidence refers to how many new cases both RCT and observational studies. Forms of there are per population in a specified time bias include; reporting bias – selective period. Incidence is usually reported as the reporting of results; publication bias - trials number of new cases per 100,000 people per that are not formally published tend to show year. Alternatively some studies present the less effect than published trials, further if number of new cases that have accumulated there are statistically significant differences over several years against a person-years between groups in a trial, these trial results denominator. This denominator is the sum of tend to get published before those of trials individual units of time that the persons in the without significant differences; language bias population are at risk of becoming a case. It – only including English language reports; takes into account the size of the underlying funding bias - source of funding for the population sample and its age structure over primary research with selective reporting of the duration of observation. results within primary studies; outcome Reliability and validity refers to how accurate variable selection bias; database bias - the instrument is. Sensitivity is the proportion including reports from some databases and of actual positives that are correctly identified not others; citation bias - preferential citation (100% sensitivity = correct identification of all of authors. Trials can also be subject to bias actual positives) and specificity is the when evaluators are not blind to treatment proportion of negatives that are correctly condition and selection bias of participants if identified (100% specificity = not identifying 4 trial samples are small . anyone as positive if they are truly not). Weighted mean difference scores refer to mean differences between treatment and † Different effect measures are reported by comparison groups after treatment (or different reviews. occasionally pre to post treatment) and in a randomized trial there is an assumption that Correlation coefficients (eg, r) indicate the both groups are comparable on this measure strength of association or relationship prior to treatment. Standardized mean between variables. They are an indication of differences are divided by the pooled prediction, but do not confirm causality due to standard deviation (or the standard deviation possible and often unforseen confounding of one group when groups are homogenous) variables. An r of 0.10 represents a weak that allows results from different scales to be association, 0.25 a medium association and combined and compared. Each study’s mean 0.40 and over represents a strong difference is then given a weighting association. Unstandardised (b) regression depending on the size of the sample and the coefficients indicate the average change in variability in the data. 0.2 represents a small the dependent variable associated with a 1 effect, 0.5 a medium effect, and 0.8 and over unit change in the dependent variable, represents a large effect4. statistically controlling for the other independent variables. Standardised Odds ratio (OR) or relative risk (RR) refers to regression coefficients represent the change the probability of a reduction (< 1) or an being in units of standard deviations to allow increase (> 1) in a particular outcome in a comparison across different scales. treatment group, or a group exposed to a risk factor, relative to the comparison group. For
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example, a RR of 0.75 translates to a limit crosses an effect size of 0.5 in either reduction in risk of an outcome of 25% direction, and for binary and correlation data, relative to those not receiving the treatment or an effect size of 0.25. GRADE also not exposed to the risk factor. Conversely, an recommends downgrading the evidence when RR of 1.25 translates to an increased risk of sample size is smaller than 300 (for binary 25% relative to those not receiving treatment data) and 400 (for continuous data), although or not having been exposed to a risk factor. for some topics, this criteria should be An RR or OR of 1.00 means there is no relaxed6. difference between groups. A medium effect is considered if RR > 2 or < 0.5 and a large effect if RR > 5 or < 0.25. lnOR stands for logarithmic OR where a lnOR of 0 shows no ║ Indirectness of comparison occurs when a difference between groups. Hazard ratios comparison of intervention A versus B is not measure the effect of an explanatory variable available but A was compared with C and B on the hazard or risk of an event. was compared with C that allows indirect comparisons of the magnitude of effect of A versus B. Indirectness of population, comparator and or outcome can also occur ‡ Inconsistency refers to differing estimates when the available evidence regarding a of treatment effect across studies (i.e. particular population, intervention, heterogeneity or variability in results) that comparator, or outcome is not available so is is not explained by subgroup analyses and inferred from available evidence. These therefore reduces confidence in the effect inferred treatment effect sizes are of lower estimate. I² is the percentage of the variability quality than those gained from head-to-head in effect estimates that is due to heterogeneity comparisons of A and B. rather than sampling error (chance) - 0% to 40%: heterogeneity might not be important, 30% to 60%: may represent moderate heterogeneity, 50% to 90%: may represent substantial heterogeneity and 75% to 100%: considerable heterogeneity. I² can be calculated from Q (chi-square) for the test of heterogeneity with the following formula;
§ Imprecision refers to wide confidence intervals indicating a lack of confidence in the effect estimate. Based on GRADE recommendations, a result for continuous data (standardised mean differences, not weighted mean differences) is considered imprecise if the upper or lower confidence
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References
1. Large MM, Nielssen O, Ryan CJ, Hayes R. Mental health laws that require dangerousness for involuntary admission may delay the initial treatment of schizophrenia. Social Psychiatry and Psychiatric Epidemiology. 2008; 43(3): 251-6. 2. Moher D, Liberati A, Tetzlaff J, Altman DG, PRISMAGroup. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. British Medical Journal. 2009; 151(4): 264-9. 3. GRADEWorkingGroup. Grading quality of evidence and strength of recommendations. British Medical Journal. 2004; 328: 1490. 4. CochraneCollaboration. Cochrane Handbook for Systematic Reviews of Interventions. 2008: Accessed 24/06/2011. 5. Rosenthal JA. Qualitative Descriptors of Strength of Association and Effect Size. Journal of Social Service Research. 1996; 21(4): 37-59. 6. GRADEpro. [Computer program]. Jan Brozek, Andrew Oxman, Holger Schünemann. Version 32 for Windows. 2008.
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