Systematic analysis of changes in cannabis use among participants in control conditions of randomised controlled trials

Introduction Cannabis remains the most used illegal substance across the globe, and negative outcomes and disorders are common. A spotlight therefore falls on reductions in cannabis use in people with cannabis use disorder. Current estimates of unassisted cessation or reduction in cannabis use rely on community surveys, and few studies focus on individuals with disorder. A key interest of services and researchers is to estimate effect size of reductions in consumption among treatment seekers who do not obtain treatment. Effects within waiting list or information-only control conditions of randomised controlled trials offer an opportunity to study this question. Method This paper examines the extent of reductions in days of cannabis use in the control groups of randomised controlled trials on treatment of cannabis use disorders. A systematic literature search was performed to identify trials that reported days of cannabis use in the previous 30 (or equivalent). Results Since all but one of the eight identified studies had delayed treatment controls, results could only be summarised across 2–4 months. Average weighted days of use in the previous 30 days fell from 24.5 to 19.9, and a meta-analysis using a random effects model showed an average reduction of 0.442 SD. However, every study had at least one significant methodological issue. Conclusions While further high-quality data is needed to confirm the observed effects, these results provide a baseline from which researchers and practitioners can estimate the extent of change required to detect effects of cannabis treatments in services or treatment trials.

Assessment of motivation to control alcohol use: The motivational thought frequency and state motivation scales for alcohol control

Introduction The Elaborated Intrusion Theory of Desire holds that desires for functional and dysfunctional goals share a common form. Both are embodied cognitive events, characterised by affective intensity and frequency. Accordingly, we developed scales to measure motivational cognitions for functional goals (Motivational Thought Frequency, MTF; State Motivation, SM), based on the existing Craving Experience Questionnaire (CEQ). When applied to increasing exercise, MTF and SM showed the same three-factor structure as the CEQ (Intensity, Imagery, Availability). The current study tested the internal structure and concurrent validity of the MTF and SM Scales when applied to control of alcohol consumption (MTF-A; SM-A). Methods Participants (N = 417) were adult tertiary students, staff or community members who had recently engaged in high-risk drinking or were currently trying to control alcohol consumption. They completed an online survey comprising the MTF-A, SM-A, Alcohol Use Disorders Identification Test (AUDIT), Readiness to Change Questionnaire (RCQ) and demographics. Results Confirmatory Factor Analysis gave acceptable fit for the MTF-A, but required the loss of one SM-A item, and was improved by intercorrelations of error terms. Higher scores were associated with more severe problems on the AUDIT and with higher Contemplation and Action scores on the RCQ. Conclusions The MTF-A and SM-A show potential as measures of motivation to control drinking. Future research will examine their predictive validity and sensitivity to change. The scales' application to both increasing functional and decreasing dysfunctional behaviours is consistent with EI Theory's contention that both goal types operate in similar ways.

Coping style and ecstasy use motives as predictors of current mood symptoms in ecstasy users

Background Elevated depressive and anxiety symptoms during childhood and adolescence have been associated with greater risk of later ecstasy use. Ecstasy users have reported using ecstasy to reduce depression or worry, or to escape. While these findings suggest that some people use ecstasy as a form of self-medication, limited research has been conducted examining the relationship between affective symptoms, coping styles and drug use motives in ecstasy users. This cross-sectional study aimed to determine if coping style and/or ecstasy use motives are associated with current mood symptoms in ecstasy users. Methods A community sample (n = 184) of 18–35 year olds who had taken ecstasy at least once in the past 12 months completed self-report measures of depression, anxiety, ecstasy use motives and coping styles. Timeline followback methods were used to collect information on lifetime ecstasy, recent drug use and life stress. Trauma exposure was measured using the Composite International Diagnostic Interview—Trauma List. Results Coping motives for ecstasy use and an emotion-focused coping style were significantly associated with current depressive and anxiety symptoms. Emotion-focused coping mediated the relationship between a history of trauma and current anxiety symptoms and moderated the relationship between recent stressful life events and current depressive symptoms. Conclusions These findings highlight the importance of interventions targeting motives for ecstasy use, and providing coping skills training for managing stressful life events among people with co-occurring depressive/anxiety symptoms and ecstasy use.

Does gender moderate the relationship between polydrug use and sexual risk-taking among Australian secondary school students under 16 years of age?

Introduction and Aims This study examines the association of alcohol and polydrug use with risky sexual behaviour in adolescents under 16 years of age and if this association differs by gender. Design and Methods The sample consisted of 5412 secondary school students under 16 years of age from Victoria, Australia. Participants completed an anonymous and confidential survey during class time. The key measures were having had sex before legal age of consent (16 years), unprotected sex before 16 (no condom) and latent-class derived alcohol and polydrug use variables based on alcohol, tobacco, cannabis, inhalants and other illegal drug use in the past month. Results There were 7.52% and 2.55% of adolescents who reported having sex and having unprotected sex before 16 years of age, respectively. After adjusting for antisocial behaviours, peers' drug use and family and school risk factors, girls were less likely to have unprotected sex (odds ratio = 0.31, P = 0.003). However, the interaction of being female and polydrug use (odds ratio = 4.52, P = 0.004) was significant, indicating that girls who engaged in polydrug use were at higher risk of having unprotected sex. For boys, the effect of polydrug use was non-significant (odds ratio = 1.44, P = 0.310). Discussion and Conclusions For girls, polydrug use was significantly associated with unprotected sex after adjusting for a range of risk factors, and this relationship was non-significant for boys. Future prevention programs for adolescent risky sexual behaviour and polydrug use might benefit from a tailored approach to gender differences.

Alcohol and depression

"A large proportion of people who experience drug problems also experience a range of mental health problems. Similarly, many people who experience mental health problems engage in hazardous drug use. The experience of these co-occurring disorders increases use of treatment services, but is associated with poorer prognosis. The implementation of effective responses has been hindered by the disaggregated systems of care that have been adopted in many countries; many problems are the outcome of poorly organised systems of care that do not reflect the needs of a large proportion of clients who experience various problems. There is a dearth of quality research to guide the development of evidence-based responses to co-occurring drug and mental health problems. This book introduces the reader to the issues, guided by a series of questions. These encourage the reader to consider the evidence about the nature and prevalence of co-occurring disorders and the challenges they create for individuals, the community and service providers. The diverse range of expertise of the contributors provides the opportunity to consider the challenges of navigating the various systems of care from the perspective of consumers, parents and clinicians. Researchers and clinicians examine the available evidence about the links between the various disorders and discuss the implications for treatment through a series of case studies. The reader is guided through evidence-based clinical decision-making. The editor and contributors argue that, while our knowledge and expertise is improving, there is a need to better resource and integrate treatment services to foster the adoption of evidence-based and effective responses. Poor systems of care don’t necessarily cause co-occurring mental health and drug problems, but they can contribute to poor outcomes."--Publisher website

Too young to drink but old enough to drive under the influence : a study of underage offenders as seen in substance abuse treatment in Texas

Driving under the influence (DUI) is a major road safety problem. Historically, alcohol has been assumed to play a larger role in crashes and DUI education programs have reflected this assumption, although recent evidence suggests that younger drivers are becoming more likely to drive drugged than to drive drunk. This is a study of 7096 Texas clients under age 21 who were admitted to state-funded treatment programs between 1997 and 2007 with a past-year DUI arrest, DUI probation, or DUI referral. Data were obtained from the State’s administrative dataset. Multivariate logistic regressions models were used to understand the differences between those minors entering treatment as a DUI as compared to a non-DUI as well as the risks for completing treatment and for being abstinent in the month prior to follow-up. A major finding was that over time, the primary problem for underage DUI drivers changed from alcohol to marijuana. Being abstinent in the month prior to discharge, having a primary problem with alcohol rather than another drug, and having more family involved were the strongest predictors of treatment completion. Living in a household where the client was exposed to alcohol abuse or drug use, having been in residential treatment, and having more drug and alcohol and family problems were the strongest predictors of not being abstinent at follow-up. As a result, there is a need to direct more attention towards meeting the needs of the young DUI population through programs that address drug as well as alcohol consumption problems.

Rural and remote road safety study : final report

• Introduction: Concern and action for rural road safety is relatively new in Australia in comparison to the field of traffic safety as a whole. In 2003, a program of research was begun by the Centre for Accident Research and Road Safety - Queensland (CARRS-Q) and the Rural Health Research Unit (RHRU) at James Cook University to investigate factors contributing to serious rural road crashes in the North Queensland region. This project was funded by the Premier’s Department, Main Roads Department, Queensland Transport, QFleet, Queensland Rail, Queensland Ambulance Service, Department of Natural Resources and Queensland Police Service. Additional funding was provided by NRMA Insurance for a PhD scholarship. In-kind support was provided through the four hospitals used for data collection, namely Cairns Base Hospital, The Townsville Hospital, Mount Isa Hospital and Atherton Hospital.----- The primary aim of the project was to: Identify human factors related to the occurrence of serious traffic incidents in rural and remote areas of Australia, and to the trauma suffered by persons as a result of these incidents, using a sample drawn from a rural and remote area in North Queensland.----- The data and analyses presented in this report are the core findings from two broad studies: a general examination of fatalities and casualties from rural and remote crashes for the period 1 March 2004 until 30 June 2007, and a further linked case-comparison study of hospitalised patients compared with a sample of non-crash-involved drivers.----- • Method: The study was undertaken in rural North Queensland, as defined by the Australian Bureau of Statistics (ABS) statistical divisions of North Queensland, Far North Queensland and North-West Queensland. Urban areas surrounding Townsville, Thuringowa and Cairns were not included. The study methodology was centred on serious crashes, as defined by a resulting hospitalisation for 24 hours or more and/or a fatality. Crashes meeting this criteria within the North Queensland region between 1 March 2004 and 30 June 2007 were identified through hospital records and interviewed where possible. Additional data was sourced from coroner’s reports, the Queensland Transport road crash database, the Queensland Ambulance Service and the study hospitals in the region.----- This report is divided into chapters corresponding to analyses conducted on the collected crash and casualty data.----- Chapter 3 presents an overview of all crashes and casualties identified during the study period. Details are presented in regard to the demographics and road user types of casualties; the locations, times, types, and circumstances of crashes; along with the contributing circumstances of crashes.----- Chapter 4 presents the results of summary statistics for all casualties for which an interview was able to be conducted. Statistics are presented separately for drivers and riders, passengers, pedestrians and cyclists. Details are also presented separately for drivers and riders crashing in off-road and on-road settings. Results from questionnaire data are presented in relation to demographics; the experience of the crash in narrative form; vehicle characteristics and maintenance; trip characteristics (e.g. purpose and length of journey; periods of fatigue and monotony; distractions from driving task); driving history; alcohol and drug use; medical history; driving attitudes, intentions and behaviour; attitudes to enforcement; and experience of road safety advertising.----- Chapter 5 compares the above-listed questionnaire results between on-road crash-involved casualties and interviews conducted in the region with non-crash-involved persons. Direct comparisons as well as age and sex adjusted comparisons are presented.----- Chapter 6 presents information on those casualties who were admitted to one of the study hospitals during the study period. Brief information is given regarding the demographic characteristics of these casualties. Emergency services’ data is used to highlight the characteristics of patient retrieval and transport to and between hospitals. The major injuries resulting from the crashes are presented for each region of the body and analysed by vehicle type, occupant type, seatbelt status, helmet status, alcohol involvement and nature of crash. Estimates are provided of the costs associated with in-hospital treatment and retrieval.----- Chapter 7 describes the characteristics of the fatal casualties and the nature and circumstances of the crashes. Demographics, road user types, licence status, crash type and contributing factors for crashes are presented. Coronial data is provided in regard to contributing circumstances (including alcohol, drugs and medical conditions), cause of death, resulting injuries, and restraint and helmet use.----- Chapter 8 presents the results of a comparison between casualties’ crash descriptions and police-attributed crash circumstances. The relative frequency of contributing circumstances are compared both broadly within the categories of behavioural, environmental, vehicle related, medical and other groupings and specifically for circumstances within these groups.----- Chapter 9 reports on the associated research projects which have been undertaken on specific topics related to rural road safety.----- Finally, Chapter 10 reports on the conclusions and recommendations made from the program of research.---- • Major Recommendations : From the findings of these analyses, a number of major recommendations were made: + Male drivers and riders - Male drivers and riders should continue to be the focus of interventions, given their very high representation among rural and remote road crash fatalities and serious injuries.----- - The group of males aged between 30 and 50 years comprised the largest number of casualties and must also be targeted for change if there is to be a meaningful improvement in rural and remote road safety.----- + Motorcyclists - Single vehicle motorcycle crashes constitute over 80% of serious, on-road rural motorcycle crashes and need particular attention in development of policy and infrastructure.----- - The motorcycle safety consultation process currently being undertaken by Queensland Transport (via the "Motorbike Safety in Queensland - Consultation Paper") is strongly endorsed. As part of this process, particular attention needs to be given to initiatives designed to reduce rural and single vehicle motorcycle crashes.----- - The safety of off-road riders is a serious problem that falls outside the direct responsibility of either Transport or Health departments. Responsibility for this issue needs to be attributed to develop appropriate policy, regulations and countermeasures.----- + Road safety for Indigenous people - Continued resourcing and expansion of The Queensland Aboriginal Peoples and Torres Strait Islander Peoples Driver Licensing Program to meet the needs of remote and Indigenous communities with significantly lower licence ownership levels.----- - Increased attention needs to focus on the contribution of geographic disadvantage (remoteness) factors to remote and Indigenous road trauma.----- + Road environment - Speed is the ‘final common pathway’ in determining the severity of rural and remote crashes and rural speed limits should be reduced to 90km/hr for sealed off-highway roads and 80km/hr for all unsealed roads as recommended in the Austroads review and in line with the current Tasmanian government trial.----- - The Department of Main Roads should monitor rural crash clusters and where appropriate work with local authorities to conduct relevant audits and take mitigating action. - The international experts at the workshop reviewed the data and identified the need to focus particular attention on road design management for dangerous curves. They also indicated the need to maximise the use of audio-tactile linemarking (audible lines) and rumble strips to alert drivers to dangerous conditions and behaviours.----- + Trauma costs - In accordance with Queensland Health priorities, recognition should be given to the substantial financial costs associated with acute management of trauma resulting from serious rural and remote crashes.----- - Efforts should be made to develop a comprehensive, regionally specific costing formula for road trauma that incorporates the pre-hospital, hospital and post-hospital phases of care. This would inform health resource allocation and facilitate the evaluation of interventions.----- - The commitment of funds to the development of preventive strategies to reduce rural and remote crashes should take into account the potential cost savings associated with trauma.----- - A dedicated study of the rehabilitation needs and associated personal and healthcare costs arising from rural and remote road crashes should be undertaken.----- + Emergency services - While the study has demonstrated considerable efficiency in the response and retrieval systems of rural and remote North Queensland, relevant Intelligent Transport Systems technologies (such as vehicle alarm systems) to improve crash notification should be both developed and evaluated.----- + Enforcement - Alcohol and speed enforcement programs should target the period between 2 and 6pm because of the high numbers of crashes in the afternoon period throughout the rural region.----- + Drink driving - Courtesy buses should be advocated and schemes such as the Skipper project promoted as local drink driving countermeasures in line with the very high levels of community support for these measures identified in the hospital study.------ - Programs should be developed to target the high levels of alcohol consumption identified in rural and remote areas and related involvement in crashes.----- - Referrals to drink driving rehabilitation programs should be mandated for recidivist offenders.----- + Data requirements - Rural and remote road crashes should receive the same quality of attention as urban crashes. As such, it is strongly recommended that increased resources be committed to enable dedicated Forensic Crash Units to investigate rural and remote fatal and serious injury crashes.----- - Transport department records of rural and remote crashes should record the crash location using the national ARIA area classifications used by health departments as a means to better identifying rural crashes.----- - Rural and remote crashes tend to be unnoticed except in relatively infrequent rural reviews. They should receive the same level of attention and this could be achieved if fatalities and fatal crashes were coded by the ARIA classification system and included in regular crash reporting.----- - Health, Transport and Police agencies should collect a common, minimal set of data relating to road crashes and injuries, including presentations to small rural and remote health facilities.----- + Media and community education programmes - Interventions seeking to highlight the human contribution to crashes should be prioritised. Driver distraction, alcohol and inappropriate speed for the road conditions are key examples of such behaviours.----- - Promotion of basic safety behaviours such as the use of seatbelts and helmets should be given a renewed focus.----- - Knowledge, attitude and behavioural factors that have been identified for the hospital Brief Intervention Trial should be considered in developing safety campaigns for rural and remote people. For example challenging the myth of the dangerous ‘other’ or ‘non-local’ driver.----- - Special educational initiatives on the issues involved in rural and remote driving should be undertaken. For example the material used by Main Roads, the Australian Defence Force and local initiatives.

Suicidal ideation, suicide attempts, and HIV infection

A cross-sectional study was performed to investigate the prevalence and predictors of suicidal ideation and past suicide attempt in an Australian sample of human imumunodeficiency virus (HIV)-positive and HIV-negative homosexual and bisexual men. Sixty-five HIV-negative and 164 HIV-positive men participated. A suicidal ideation score was derived from using five items selected from the Beck Depression Inventory and the General Health Questionnaire (28-item version). Lifetime and current prevalence rates of psychiatric disorder were evaluated with the Diagnostic Interview Schedule Version-III-R. The HIV-positive (Centers for Disease Control and Prevention [CDC] Stage IV) men (n=85) had significantly higher total suicidal ideation scores than the asymptomatic HIV-positive men (CDC Stage II/III) (n=79) and the HIV-negative men. High rates of past suicide attempt were detected in the HIV-negative (29%) and HIV-positive men (21%). Factors associated with suicidal ideation included being HIV-positive, the presence of current psychiatric disorder, higher neuroticism scores, external locus of control, and current unemployment. In the HIV-positive group analyzed separately, higher suicidal ideation was discriminated by the adjustment to HIV diagnosis (greater hopelessness and lower fighting spirit), disease factors (greater number of current acquired immunodeficiency syndrome [AIDS]-related conditions), and background variables (neuroticism). Significant predictors of a past attempted suicide were a positive lifetime history of psychiatric disorder (particularly depression diagnoses), a lifetime history of injection drug use, and a family history of suicide attempts. The findings indicate increased levels of suicidal ideation in symptomatic HIV-positive men and highlight the role that multiple psychosocial factors associated with suicidal ideation and attempted suicide play in this population.

At work or play : a comparison of private property vehicle crashes with those occurring on public roads in north Queensland.

Objective: To define characteristics of vehicle crashes occurring on rural private property in north Queensland with an exploration of associated risk factors. Design: Descriptive analysis of private property crash data collected by the Rural and Remote Road Safety Study. Setting: Rural and remote north Queensland. Participants: A total of 305 vehicle controllers aged 16 years or over hospitalised at Atherton, Cairns, Mount Isa or Townsville for at least 24 hours as a result of a vehicle crash. Main outcome measure: A structured questionnaire completed by participants covering crash details, lifestyle and demographic characteristics, driving history, medical history, alcohol and drug use and attitudes to road use. Results: Overall, 27.9% of interviewees crashed on private property, with the highest proportion of private road crashes occurring in the North West Statistical Division (45%). Risk factors shown to be associated with private property crashes included male sex, riding off-road motorcycle or all-terrain vehicle, first-time driving at that site, lack of licence for vehicle type, recreational use and not wearing a helmet or seatbelt. Conclusions: Considerable trauma results from vehicle crashes on rural private property. These crashes are not included in most crash data sets, which are limited to public road crashes. Legislation and regulations applicable to private property vehicle use are largely focused on workplace health and safety, yet work-related crashes represent a minority of private property crashes in north Queensland.

Prags Boulevard in Copenhagen : from run-down strip to boulevard

Prags Boulevard will form a 2km long pedestrian spine running east-west between the historic cities of Copenhagen and Amager. It is located on a some-what run down site, which accommodated illicit functions such as casual drug use and drinking, as well as sheds for squatters. The renovation of this site by the city of Copenhagen forms part of the Holmbladsgade renovation project, and a two-phase competition was held in 2001 to develop a green area and meeting place, transforming it into a place that residents would want to visit rather than avoid. The designer, local landscape architect Kristine Jensens recognises that though the site is linear it ‘has no traffic importance’, though as she notes ‘we like the project because it runs straight east west from the city pulse to the water of Oresund’. In developing the project, she has attempted to allow it to ‘run parallel’ to its existing illicit uses, using a ‘light touch’ of insertions. While it would be hard to describe the project as truly light in its touch (graphically, it is a very bold scheme), there is no doubt that it is parallel: in terms of use it runs alongside rather than against existing uses; in terms of its type it’s all about length, like a boulevard, although it clearly differs from a boulevard in other respects.

An examination of the utility of the AUDIT in people with schizophrenia

Objective: To examine the reliability and validity of the Alcohol Use Disorders Identification Test (AUDIT) compared to a structured diagnostic interview, the Composite international Diagnostic Interview (CIDI; 12-month version) in psychiatric patients with a diagnosis of schizophrenia. Method: Patients (N = 71, 53 men) were interviewed using the CIDI (Alcohol Misuse Section; 12-month version) and then completed the AUDIT. Results: The CIDI identified 32.4% of the sample as having an alcohol use disorder. Of these, 5 (7.0%) met diagnostic criteria for harmful use of alcohol, 1 (1.4%) met diagnostic criteria for alcohol abuse and 17 (23.9%) met diagnostic criteria for alcohol dependence. The AUDIT was found to have good internal reliability (coefficient = 0.85). An AUDIT cutoff of greater than or equal to 8 had a sensitivity of 87% and specificity of 90% in detecting CIDI-diagnosed alcohol disorders. All items except Item 9 contributed significantly to discriminant validity. Conclusions: The findings replicate and extend previous findings of high rates of alcohol use disorders in people with severe mental illness. The AUDIT was found to be reliable and valid in this sample and can be used with confidence as a screening instrument for alcohol use disorders in people with schizophrenia.

Hard Lessons : Reflections on Governance and Crime Control in Late Modernity

The essays in this book catalogue a wide and varied range of instances where 'things go wrong' in the practice of criminal justice. The contributions document instances where laws, policies and practices have produced unintended consequences of the most deleterious kind, drawing attention to 'boot camps', detention centres and specific penal policies such as 'short, sharp shock' and 'three strikes and you're out'. Also examined are policing practices such as 'zero tolerance', 'saturation policing' and punitive laws in the area of drug use, sex offences, and prostitution. It will be demonstrated that in each of these cases, the objectives of government resulted in the creation of new and unforeseen problems requiring further reform to the justice system.

Alcohol consumption by undergraduate students

Assessed correlates of alcohol consumption (AC) in 212 undergraduates (81 "college" and 131 "noncollege" residents [COLRs and NCOLRs], mean ages 18.9 and 18.6 yrs, respectively) and studied the proportion who were drinking at potentially harmful levels (HLs). This study also examined changes in AC during the course of the 1st semester and predicted drinking levels in the 2nd semester from demographics, drug use, social variables and self-efficacy data. Data were collected using self-administered questionnaires. During both semesters, the COLRs reported drinking significantly more alcohol than NCOLRs, but during vacation the intake of the 2 groups was almost equal. Higher AC in the 2nd semester was best predicted by higher AC during the 1st semester, followed by more AC by friends and higher parental occupation status. Female COLRs were those most likely to be drinking at HLs. Results also showed that a significant proportion of COLRs were drinking at HLs.

Psychopathology during childhood and adolescence predicts delusional-like experiences in adults : a 21-year birth cohort study

Objective: Community surveys have shown that many otherwise well individuals report delusional-like experiences. The authors examined psychopathology during childhood and adolescence as a predictor of delusional-like experiences in young adulthood. ---------- Method: The authors analyzed prospective data from the Mater-University of Queensland Study of Pregnancy, a birth cohort of 3,617 young adults born between 1981 and 1983. Psychopathology was measured at ages 5 and 14 using the Child Behavior Checklist (CBCL) and at age 14 using the Youth Self-Report (YSR). Delusional-like experiences were measured at age 21 using the Peters Delusional Inventory. The association between childhood and adolescent symptoms and later delusional-like experiences was examined using logistic regression. ---------- Results: High CBCL scores at ages 5 and 14 predicted high levels of delusional-like experiences at age 21 (odds ratios for the highest versus the other quartiles combined were 1.25 and 1.85, respectively). Those with YSR scores in the highest quartile at age 14 were nearly four times as likely to have high levels of delusional-like experiences at age 21 (odds ratio=3.71). Adolescent-onset psychopathology and continuous psychopathology through both childhood and adolescence strongly predicted delusional-like experiences at age 21. Hallucinations at age 14 were significantly associated with delusional-like experiences at age 21. The general pattern of associations persisted when adjusted for previous drug use or the presence of nonaffective psychoses at age 21. ---------- Conclusion: Psychopathology during childhood and adolescence predicts adult delusional-like experiences. Understanding the biological and psychosocial factors that influence this developmental trajectory may provide clues to the pathogenesis of psychotic-like experiences.

Management of comorbidity

Comorbidity of substance use disorders and mental disorders is very common, and there is substantial heterogeneity within subgroups in terms of both their characteristics and the nature of causal relationships between the disorders. Assessment and management strategies need to deal with both the size of the problem across the community and its severe impact in some subgroups, including those with psychosis. At this stage, the research base from which we can derive recommendations is very narrow, but it does offer a foundation for preliminary conclusions. This chapter reviews the current evidence and makes some suggestions for assessment and for both psychological and pharmacological management.