Predicting institutional violence in offenders with intellectual disabilities: the predictive efficacy of the VRAG and the HCR-20

The key role of base rates: systematic review and meta-analysis of the predictive value of four risk assessment instruments

AIMS OF THE STUDY

Many countries have seen a decline in recidivism rates over the past decades. These base rates are pertinent information for assessing the recidivism risk of offenders. They provide a foundation for clinical assessment and an empirical basis for risk assessment instrument norms, which inform expected recidivism rates. The present study explored the extent to which base rates influence the validity of risk assessment instruments.

METHODS

We systematically reviewed the available evidence on the discrimination ability of four well-established risk assessment instruments used to estimate the probability of recidivism for general (Level of Service Inventory-Revised [LSI-R]), violent (Violence Risk Appraisal Guide [VRAG]), sexual (Static-99R), and intimate partner violent offences (Ontario Domestic Assault Risk Assessment [ODARA]). We conducted a bivariate logit-normal random effects meta-analysis of sensitivity and false positive rates and modelled the positive and negative predictive values. We used base rates as reported in (a) the construction samples of each risk assessment instrument and (b) recent official statistics and peer-reviewed articles for different offence categories and countries. To assess the risk of bias, we used the Joanna Briggs Institute Critical Appraisal Checklist for Diagnostic Test Accuracy Studies.

RESULTS

We screened 644 studies and subsequently analysed 102, of which 96 were included in the systematic review and 24 in the meta-analyses. Discrimination was comparable for all four instruments (median area under the curve = 0.68-0.71). The information needed to calculate summary statistics of sensitivity and false positive rate was often not reported, and a risk of bias may be present in up to half of the studies. The largest summary sensitivity and false positive rate were estimated for the ODARA, followed by the LSI-R, the VRAG, and the Static-99R. If base rates are low, positive predictive values tend to be relatively low, while negative predictive values are higher: positive predictive value = 0.032-0.133 and negative predictive value = 0.985-0.989 for sexual offences; positive predictive value = 188-0.281 and negative predictive value = 0.884-0.964 for intimate partner violence; positive predictive value = 0.218-0.241 and negative predictive value = 0.907-0.942 for violent offences; positive predictive value = 0.335-0.377 and negative predictive value = 0.809-0.810 for general offences.

CONCLUSIONS

When interpreting the results of individual risk assessments, it is not sufficient to provide the discrimination of the instrument; the risk statement must also address the positive predictive value and discuss its implications for the specific case. As recidivism rates are neither stable over time nor uniform across countries or samples, the primary interpretation of risk assessment instruments should rely on the percentile rank. Expected recidivism rates should be interpreted with caution. However, our results are drawn from a limited database, as studies not reporting sufficient information were excluded from analyses and it was only possible to identify current base rates for modelling positive and negative predictive values for certain countries. International standards for consistently collecting and reporting base rates are important to better identify crime trends. Future research on the validity of risk assessment instruments should follow rigorous reporting standards.

Risk for intellectual disability populations in inpatient forensic settings in the United Kingdom: A literature review

BACKGROUND

People with an intellectual disability who commit a criminal offence can be detained, by a court, in a forensic inpatient facility. There is limited understanding of how inpatients with an intellectual disability and their nurses navigate risk in U.K. forensic services.

METHODS

A traditional literature review design was followed to map evidence (2000-2021) around the forensic and health and wellbeing risks faced by inpatients with an intellectual disability, nurses' perceptions of managing risk, and patient experiences of informing risk assessment and management. Papers were analysed thematically.

RESULTS

Findings suggest that restrictive measures to mitigate forensic risks (e.g., violence) can exacerbate the risk of poor health and wellbeing outcomes. There was some limited evidence of direct patient involvement in risk assessment and management.

CONCLUSION

Further research is required to explore how forensic inpatients with an intellectual disability can have input in care planning, risk assessment and management.

Criminal recidivism in offenders with and without intellectual disability sentenced to forensic psychiatric care in Sweden-A 17-year follow-up study

BACKGROUND

Offenders with intellectual disability (ID) constitute a distinct subgroup of offenders with mental disorders. Regarding criminal recidivism, it is unclear whether or not offenders with ID in forensic psychiatric settings differ from offenders without ID. Factors associated with criminal recidivism among offenders with ID have been scarcely investigated.

AIM

To investigate the association between ID and criminal recidivism among offenders sentenced to forensic psychiatric care and to explore the impact of clinical, sociodemographic and offense variables.

MATERIALS AND METHODS

We conducted a retrospective cohort study based on Swedish nationwide registers. A total of 3,365 individuals being sentenced to forensic psychiatric care in Sweden in 1997-2013 were followed from the forensic psychiatric assessment until first reconviction, death, emigration, or 31 December 2013, whichever occurred first. Cox regression models compared rates of recidivism in individuals with and without ID. Impact of clinical, sociodemographic, and offense variables on risk of criminal recidivism was presented as hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

Out of 3,365 offenders sentenced to forensic psychiatric care, 259 (7.7%) were diagnosed with ID. During follow-up (0-17 years, median 6 years), one third (n = 1,099) of the study population relapsed into criminality, giving a recidivism rate of 50.5 per 1,000 person-years. We observed an association between ID and a decreased risk of recidivism (HR 0.8, 95% CI 0.6-1.0, p = 0.063), although this reached statistical significance only for the subgroup of male offenders (HR 0.8, 95% CI 0.6-1.0, p = 0.040) and not females (HR 1.0, 95% CI 0.6-1.8). ID offenders with concurrent ADHD tended to have a higher rate of recidivism (73.9 per 1,000 person-years, HR 1.2, 95% CI 0.6-2.4) than ID offenders without ADHD (42.5 per 1,000 person-years, HR 0.8, 95% CI 0.6-1.1). Amongst ID offenders, concurrent autism spectrum disorder, young age or male sex were not associated with recidivism, while previous criminal convictions were strongly associated with recidivism.

CONCLUSION

A diagnosis of ID was associated with a lower risk of criminal recidivism among male offenders sentenced to forensic psychiatric care. The association between ADHD and recidivism among ID offenders highlights eligible focus areas in the management of offenders with ID.

Predicting aggression in adults with intellectual disability: A pilot study of the predictive efficacy of the Current Risk of Violence and the Short Dynamic Risk Scale

BACKGROUND

Structured assessments have been shown to assist professionals to evaluate the risk of aggression in secure services for general offender populations and more recently among adults with intellectual disabilities. There is a need to develop intellectual disability sensitive measures for predicting risk of aggression in community samples, especially tools with a focus on dynamic variables.

METHODS

The study prospectively followed 28 participants for up to 2 months to test whether the Current Risk of Violence (CuRV) and Short Dynamic Risk Scale (SDRS) were able to predict verbal and physical aggression in a community sample of adults with intellectual disability.

RESULTS

CuRV and SDRS ratings significantly predicted verbal and physical aggression over a 2-month period.

CONCLUSIONS

The current study supports the use of the CuRV with adults with intellectual disability living in community settings. The CuRV and SDRS are worthy of future development and evaluation in independent investigations.

Assessment of Risk for Seclusion Among Forensic Inpatients: Validation and Modification of the Risk of Administrative Segregation Tool (RAST)

Seclusion is used in psychiatric care to protect patients and staff or to manage aggression but may have adverse effects. The ability to identify at-risk patients could help reduce seclusion. This study tested the Risk of Administrative Segregation Tool's (RAST) ability to predict any seclusions among 229 male forensic inpatients followed for up to 1 year of hospitalization, and days spent secluded, controlling for length of stay. RAST scores were lower than in correctional samples. The RAST did not predict seclusions in Year 1, but modification of three items to fit the forensic population (RAST-F) offered a small improvement. Among 62 patients hospitalized for more than 1 year, the RAST significantly predicted seclusions in Year 2, and the modifications improved prediction. The present modest findings support the RAST's potential to help identify patients most in need of clinical efforts to avert seclusion. Replication in larger samples, including female patients, is needed.

Clinical, Demographic, and Criminal Behavior Characteristics of Patients With Intellectual Disabilities in a Canadian Forensic Program

Background: People with intellectual disability (ID) and forensic issues constitute a challenging clinical group that has been understudied in forensic settings. Methods: We assessed the characteristics of patients with ID under the authority of the Ontario Review Board (ORB) in a large forensic program of a tertiary psychiatric hospital (excluding those with a cognitive disorder) and compared their characteristics with those of a non-ID control group. Results: Among 510 adult ORB patients, 47 had an ID diagnosis. ID patients were of younger age at index offense, with a lower level of education, and were less likely to have been married or employed, more likely to have committed a sexual offense, more likely to have a diagnosis of paraphilia, less likely to be "not criminally responsible," and more likely to be "unfit to stand trial." They were also more likely to have committed their index offenses against care professionals and be treated in a secure unit. Conclusion: Our findings have major implications for clinicians, clinical leaders, and policymakers about the specific needs of patients with ID presenting with forensic issues and differing needs in terms of treatment and risk management.

Long-stay patients with and without intellectual disability in forensic psychiatric settings: comparison of characteristics and needs

BACKGROUND

In recent years, concerns have been raised that too many patients stay for too long in forensic psychiatric services and that this is a particular problem in those with an intellectual disability.

AIMS

To compare the characteristics, needs, and care pathways of long-stay patients with and without intellectual disability within forensic psychiatric hospital settings in England.

METHOD

File reviews and questionnaires were completed for all long-stay patients in high secure and a representative sample of those in medium secure settings in England. Between-group analyses comparing patients with and without intellectual disability are reported.

RESULTS

Of the 401 long-stay patients, the intellectual disability and non-intellectual disability groups were strikingly similar on many sociodemographic, clinical and forensic variables. The intellectual disability group had significantly lower lengths of stay, fewer criminal sections, restriction orders and prison transfers, and higher levels of behavioural incidents and risk assessment scores.

CONCLUSIONS

In spite of similar offence histories and higher risk levels, those with intellectual disability appear to be diverted away from the criminal justice system and have shorter lengths of stay. This has implications about the applicability of the Transforming Care programme to this group.

Measuring relational security in forensic mental health services

Aims and method Relational security is an important component of care and risk assessment in mental health services, but the utility of available measures remains under-researched. This study analysed the psychometric properties of two relational security tools, the See Think Act (STA) scale and the Relational Security Explorer (RSE). Results The STA scale had good internal consistency and could highlight differences between occupational groups, whereas the RSE did not perform well as a psychometric measure. Clinical implications The measures provide unique and complimentary perspectives on the quality of relational security within secure services, but have some limitations. Use of the RSE should be restricted to its intended purpose; to guide team discussions about relational security, and services should refrain from collecting and aggregating this data. Until further research validates their use, relational security measurement should be multidimensional and form part of a wider process of service quality assessment.

How effective are risk assessments/measures for predicting future aggressive behaviour in adults with intellectual disabilities (ID): A systematic review and meta-analysis

BACKGROUND

Risk assessments assist professionals in the identification and management of risk of aggression. The present study aimed to systematically review evidence on the efficacy of assessments for managing the risk of physical aggression in adults with intellectual disabilities (ID).

METHODS

A literature search was conducted using the databases PsycINFO, EMBASE, MEDLINE, Web of Science, and Google Scholar. Electronic and hand searches identified 14 studies that met the inclusion criteria. Standardised mean difference effect sizes Area Under Curve (AUC) were calculated for studies. Random effects subgroup analysis was used to compare different types of risk measures (Actuarial, Structured Professional Judgment and dynamic), and prospective vs. catch-up longitudinal study designs.

RESULTS

Overall, evidence of predictive validity was found for risk measures with ID populations: (AUC)=0.724, 95% CI [0.681, 0.768]. There was no variation in the performance of different types of risk measures, or different study design.

CONCLUSIONS

Risk assessment measures predict the likelihood of aggression in ID population and are comparable to those in mainstream populations. Further meta-analysis is necessary when risk measures are more established in this population.

Researching outcomes from forensic services for people with intellectual or developmental disabilities: a systematic review, evidence synthesis and expert and patient/carer consultation

Background

Inpatient services for people with intellectual and other types of developmental disabilities (IDD) who also have forensic or risk issues are largely provided in secure hospitals. Although this is a health service sector with high levels of expenditure, there is limited empirical information on patient outcomes from such services. In order for a future substantive longitudinal outcomes study in forensic IDD services to be informed and feasible, more needs to be understood about the outcome domains that are of relevance and importance and how they should be measured. A preliminary series of studies was therefore undertaken.

Objectives

To synthesise evidence in relation to the outcome domains that have been researched in the existing literature from hospital and community forensic services for people with IDD, within the broad domains of service effectiveness, patient safety and patient experience. To identify a definitive framework of outcome domains (and associated measures and indicators) based both on this research evidence and on the views of patients, carers and clinicians. To synthesise the information gathered in order to inform design of future multisite longitudinal research in the sector.

Design

Three linked studies were conducted. Stage 1 was a systematic review and evidence synthesis of outcome domains and measures as found within the forensic IDD literature. Stage 2 was a consultation exercise with 15 patients with IDD and six carers. Stage 3 was a modified Delphi consensus exercise with 15 clinicians and experts using the information gathered at stages 1 and 2.

Results

At stage 1, 60 studies that researched a range of outcomes in forensic IDD services were identified from the literature. This resulted in the construction of an initial framework of outcome domains. The consultation with patients and carers at stage 2 added to these framework domains that related particularly to carer experience and the level of support post discharge in the community. The Delphi process at stage 3 confirmed the validity of the resulting framework for clinician. This survey also identified the outcome measures preferred by clinicians and those that are currently utilised in services. Thus, indicators of appropriate measures in some important domains were identified, although there was a paucity of measures in other domains.

Conclusions

Together, these three linked studies led to the development of an evidence-based framework of key outcome domains and subdomains. A provisional list of associated measures and indicators was developed, although with the paucity of measures in some domains development of specific indicators may be required. With further refinement this could eventually be utilised by services and commissioners for comparative purposes, and in future empirical research on outcomes in forensic IDD services. An outline research proposal closely linked to recent policy initiatives was proposed. Limitations of the study include the relatively small number of carers and patients and range of experts consulted.

Future work

This would comprise a national longitudinal study tracking IDD in patients through hospitalisation and discharge.

Study registration

This study is registered as PROSPERO CRD42015016941.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

A systematic review and synthesis of outcome domains for use within forensic services for people with intellectual disabilities

BACKGROUND

There is limited empirical information on service-level outcome domains and indicators for the large number of people with intellectual disabilities being treated in forensic psychiatric hospitals.

AIMS

This study identified and developed the domains that should be used to measure treatment outcomes for this population.

METHOD

A systematic review of the literature highlighted 60 studies which met eligibility criteria; they were synthesised using content analysis. The findings were refined within a consultation and consensus exercises with carers, patients and experts.

RESULTS

The final framework encompassed three a priori superordinate domains: (a) effectiveness, (b) patient safety and (c) patient and carer experience. Within each of these, further sub-domains emerged from our systematic review and consultation exercises. These included severity of clinical symptoms, offending behaviours, reactive and restrictive interventions, quality of life and patient satisfaction.

CONCLUSIONS

To index recovery, services need to measure treatment outcomes using this framework.

DECLARATION OF INTEREST

None.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY) licence.

Predicting Institutional Aggression in Offenders with Intellectual Disabilities Using the Violence Risk Appraisal Guide

BACKGROUND

One of the most extensively tested risk assessment instruments in offenders with an intellectual disability (OIDs) is the Violence Risk Appraisal Guide (VRAG). The purpose of this prospective study was to test the ability of this instrument to predict institutional aggression in OIDs.

METHOD

VRAG scores were collected for 52 OIDs, and staff registered aggressive incidents during a period of 6 months. Predictive accuracy was analysed using several performance indicators.

RESULTS

The VRAG was not able to significantly predict aggressive behaviour, although a trend towards significance was found for interpersonal physical aggression. Furthermore, the VRAG was only accurate in prospectively identifying low-risk individuals.

CONCLUSION

Compared to other studies, demonstrating good predictive validity for institutional aggression in OIDs, the VRAG performed poorly in this study. The usefulness of this instrument in identifying high-risk offenders is questioned. Until further evidence is available from studies using multiple performance indicators, clinicians have to be very careful in relying on the results of a risk assessment tool.

The Structured Assessment of Violence Risk in Adults with Intellectual Disability: A Systematic Review

BACKGROUND

While structured professional judgement approaches to assessing and managing the risk of violence have been extensively examined in mental health/forensic settings, the application of the findings to people with an intellectual disability is less extensively researched and reviewed. This review aimed to assess whether risk assessment tools have adequate predictive validity for violence in adults with an intellectual disability.

METHODS

Standard systematic review methodology was used to identify and synthesize appropriate studies.

RESULTS

A total of 14 studies were identified as meeting the inclusion criteria. These studies assessed the predictive validity of 18 different risk assessment tools, mainly in forensic settings. All studies concluded that the tools assessed were successful in predicting violence. Studies were generally of a high quality.

CONCLUSIONS

There is good quality evidence that risk assessment tools are valid for people with intellectual disability who offend but further research is required to validate tools for use with people with intellectual disability who offend.

Predicting hospital aggression in secure psychiatric care

BACKGROUND

Risk assessment instruments have become a preferred means for predicting future aggression, claiming to predict long-term aggression risk.

AIMS

To investigate the predictive value over 12 months and 4 years of two commonly applied instruments (Historical, Clinical and Risk Management - 20 (HCR-20) and Violence Risk Appraisal Guide (VRAG)).

METHOD

Participants were adult male psychiatric patients detained in a high secure hospital. All had a diagnosis of personality disorder. The focus was on aggression in hospital.

RESULTS

The actuarial risk assessment (VRAG) was generally performing better than the structured risk assessment (HCR-20), although neither approach performed particularly well overall. Any value in their predictive potential appeared focused on the longer time period under study (4 years) and was specific to certain types of aggression.

CONCLUSIONS

The value of these instruments for assessing aggression in hospital among patients with personality disorder in a high secure psychiatric setting is considered.

DECLARATION OF INTEREST

J.L.I., C.A.M. and J.K. are employed by the trust where the data were collected.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.

Predictive validity of the HCR-20 for inpatient aggression: the effect of intellectual disability on accuracy

BACKGROUND

People with intellectual disability (ID) account for a large proportion of aggressive incidents in secure and forensic psychiatric services. Although the Historical, Clinical, Risk Management 20 (HCR-20) has good predictive validity in inpatient settings, it does not perform equally in all groups and there is little evidence for its efficacy in those with ID.

METHOD

A pseudo-prospective cohort study of the predictive efficacy of the HCR-20 for those with ID (n = 109) was conducted in a UK secure mental health setting using routinely collected risk data. Performance of the HCR-20 in the ID group was compared with a comparison group of adult inpatients without an ID (n = 504). Analysis controlled for potential covariates including security level, length of stay, gender and diagnosis.

RESULTS

The HCR-20 total score was a significant predictor of any aggression and of physical aggression for both groups, although the area under the curve values did not reach the threshold for a large effect size. The clinical subscale performed significantly better in those without an ID compared with those with. The ID group had a greater number of relevant historical and risk management items. The clinicians' summary judgment significantly predicted both types of aggressive outcomes in the ID group, but did not predict either in those without an ID.

CONCLUSIONS

This study demonstrates that, after controlling for a range of potential covariates, the HCR-20 is a significant predictor of inpatient aggression in people with an ID and performs as well as for a comparison group of mentally disordered individuals without ID. The potency of HCR-20 subscales and items varied between the ID and comparison groups suggesting important target areas for improved prediction and risk management interventions in those with ID.