Timothy Slade

• PhD
• Professor (Associate) at The University of Sydney

Background: Estimates of the prevalence of DSM-IV alcohol use disorders (AUD; i.e., abuse and dependence) are consistently higher for younger adults compared with their older counterparts. However, questions remain as to whether this "youthful epidemic" of AUD is real or a methodological artifact of the prevailing classification criteria. The aim...

The use in hazardous situations criterion (hazard) is 1 of 4 criteria related to alcohol abuse in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and 1 of the 11 criteria related to the new alcohol use disorder (AUD) proposed for DSM-5. The current study aims to evaluate the hazard criterion in the context of bot...

There has been substantial recent interest in the development of a quantitative, empirically based model of psychopathology. However, the majority of pertinent research has focused on analyses of diagnoses, as described in current official nosologies. This is a significant limitation because existing diagnostic categories are often heterogeneous. I...

Aims Prompt initial contact with a treatment provider is a critical first step in seeking help for a mental or substance use disorders (SUDs). The aim of the current study was to provide estimates of patterns and predictors of delay in making initial treatment contact based on the recently completed Australian National Survey of Mental Health and W...

Background Setting rules about alcohol use and minimizing its availability in the home are known effective parent‐level strategies for reducing underage drinking risk. However, parents' restrictions and their perceptions of their child's alcohol access have rarely been considered in combination (e.g., determining if rule‐setting consistently accomp...

Background The relationship between adolescent alcohol use and emotional problems remains unclear and contradictory. These inconsistencies may in part be due to differences in the measurement and operationalization of alcohol use and emotional problems across studies, as well as confounder selection and missing data decisions. This study explores t...

This cost-utility analysis adopted societal and health sector perspectives evaluating combined and individual approaches to universal prevention of substance use, depression, and anxiety in 6,386 high school students within the Climate Schools Combined cluster randomised trial. Costs included program delivery, self-reported healthcare utilisation,...

Intervention Health4Life: a school-based eHealth intervention targeting multiple health behaviour change (MHBC). Research question Does Health4Life impact secondary outcomes of self-reported intentions regarding six lifestyle behaviours in adolescents (alcohol use, tobacco smoking, screentime, physical activity, discretionary beverage consumption,...

Objective To examine the impact of potential measurement bias (i.e., differential item functioning [DIF]) across sex, age, employment, location, and substance use disorders on the screening properties of epidemiological surveys that utilise screening questions when estimating prevalence of mood and anxiety disorders. Methods Data comprised of 15,8...

The objective of this paper is to summarise the policy implications of key findings from the 2020–22 Australian National Study of Mental Health and Wellbeing (NSMHWB). We provide an analysis of policy implications of four papers in this issue of the journal from the 2020–22 NSMHWB ( N = 15,893) and the 2007 NSMHWB ( N = 8841). The 2020–2022 NSMHWB...

Background Prior research has shown that early alcohol experiences, such as age of initiation and speed of progression between drinking milestones, vary across racial/ethnic groups. To inform culturally tailored prevention efforts, this longitudinal study examined racial/ethnic differences in the associations of drinking firsts at home and with par...

Background Previous estimates from 2007 found that co-occurring mental and/or substance use disorders were a pervasive feature of Australia’s mental health. Since that time there have been shifts and improvements in the conceptualisation and incorporation of co-occurring disorders in research and treatment settings. The current study provides up-to...

Background Around the world, people living in objectively difficult circumstances who experience symptoms of generalized anxiety disorder (GAD) do not qualify for a diagnosis because their worry is not ‘excessive’ relative to the context. We carried out the first large-scale, cross-national study to explore the implications of removing this excessi...

Objective Mental and substance use disorders are the leading causes of disability worldwide. Contemporary estimates of prevalence, severity and impairment are essential for service planning. This study provides estimates of prevalence, severity, impairment and demographic correlates of mental and substance use disorders in 2020–22 and changes in pr...

Objective: Mental and substance use disorders are the leading causes of disability worldwide. Contemporary estimates of prevalence, severity and impairment are essential for service planning. The current study provides estimates of prevalence, severity, impairment and demographic correlates of mental and substance use disorders in 2020-22, and chan...

Objective To summarise policy implications of key findings from the 2020-22 Australian National Study of Mental Health and Wellbeing (NSMHWB).Methods: Analysis of policy implications of four papers in this issue of the journal from the 2020-22 NSMHWB (N=15,893) and the 2007 NSMHWB (N=8,841). Results: The 2020-2022 NSMHWB reported a lifetime prevale...

More comprehensive modeling of psychopathology in youth is needed to facilitate a developmentally informed expansion of the Hierarchical Taxonomy of Psychopathology (HiTOP) model. In this study, we examined a symptom-level model of the structure of psychopathology in children and adolescents—most aged 11 to 17 years—bringing together data from larg...

Objectives To prospectively assess rates of QT prolongation, arrhythmia, syncope, and sudden cardiac death (SCD) in a cohort of people with heroin dependence. Methods To estimate rates of QT prolongation, arrhythmia, and syncope, a subcohort (n = 130) from the Australian Treatment Outcomes Study, a prospective longitudinal cohort study of 615 peop...

Background Prevention and early intervention of alcohol use disorder (AUD) is a public health priority, yet there are gaps in our understanding of how AUD emerges, which symptoms of AUD come first, and whether there are modifiable risk factors that forecast the development of the disorder. This study investigated potential early‐warning‐sign sympto...

Background In recent years, psychological distress in Western countries has rapidly increased among older adolescents while alcohol use has declined, though little is known about younger adolescents. It is also unclear if and how these trends relate to co‐occurring alcohol use and distress. This study sought to examine temporal changes in the preva...

Background and aims Alcohol use and anxiety often co‐occur, causing increased severity impairment. This protocol describes a randomized controlled trial (RCT) that aims to test the efficacy and cost‐effectiveness of a web‐based, self‐guided alcohol and anxiety‐focused program, compared with a web‐based brief alcohol‐focused program, for young adult...

Background Addressing aggressive behavior in adolescence is a key step toward preventing violence and associated social and economic costs in adulthood. This study examined the secondary effects of the personality-targeted substance use preventive program Preventure on aggressive behavior from ages 13 to 20. Methods In total, 339 young people from...

Heavy and disordered alcohol consumption is a known risk factor for several health conditions and is associated with considerable disease burden. However, at low‐to‐moderate levels, evidence suggests that drinking is associated with reduced risk for certain health outcomes. Whether these findings represent genuine protective effects or mere methodo...

Objectives To investigate the effectiveness of a school‐based multiple health behaviour change e‐health intervention for modifying risk factors for chronic disease (secondary outcomes). Study design Cluster randomised controlled trial. Setting, participants Students (at baseline [2019]: year 7, 11–14 years old) at 71 Australian public, independen...

Background and aims: Adolescent polysubstance use has been associated with adverse social and health outcomes. Our aim was to measure rates and transitions to polysubstance use during adolescence and identify factors associated with initiation and discontinuation of polysubstance use. Design: Prospective cohort study. Multistate Markov modelling...

Across high-income countries, adolescent emotional concerns have been increasing in prevalence over the past two decades and it is unclear why this is occurring, including if and how substance use relates to these changing trends. On the other hand, substance use has been generally declining, and little is known about the role of emotional concerns...

Purpose Characterizing trends and correlates of adolescent psychological distress is important due to observed global increases over the last 20 years. Substance use is a commonly discussed correlate, though we lack an understanding about how co-occurrence of these concerns has been changing over time. Methods Data came from repeated, representati...

Importance: Observational evidence often suggests a J-shaped curve between alcohol consumption and risk for type 2 diabetes, with sex-discrepant relationships, but it is unclear whether these findings reflect genuine causal relationships. While genetic-based methods can enhance causal inference, existing studies employing these approaches are limit...

Lifestyle risk behaviours—physical inactivity, poor diet, poor sleep, recreational screen time, and alcohol and tobacco use—collectively known as the “Big 6” emerge during adolescence and significantly contribute to chronic disease development into adulthood. To address this issue, the Health4Life program targeted the Big 6 risk behaviours simultan...

Background This study examined cross-sectional associations between e-cigarette use and (i) perceived peer use of e-cigarettes and (ii) bullying (perpetration and/or victimisation) in Australian adolescents. Methods Data were collected in 2022 as part of a cluster randomised controlled trial. Logistic regressions examined associations between e-ci...

More comprehensive modelling of psychopathology in youth is needed to facilitate a developmentally informed expansion of the Hierarchical Taxonomy of Psychopathology (HiTOP) model. This study examined a symptom-level model of the structure of psychopathology in youth—most aged 11-17 years—bringing together data from large clinical, community, and r...

Background: Substance use disorders negatively affect global disease burden. Effective preventive interventions are available, but whether they provide value for money is unclear. Aims: This review looks at the cost-effectiveness evidence of preventive interventions for cannabis use, opioid misuse and illicit drug use. Method: Literature searc...

Background Mental health and substance use disorders typically emerge early in life with impacts extending into early adulthood. Longitudinal studies are well-placed to investigate the progression of mental health and substance use disorders in adolescents. However, a significant challenge of longitudinal studies is sample attrition, or failure to...

Background: Parents play a critical role in delaying adolescent initiation of alcohol and other drug use. However, the majority of prevention programs focus on adolescents only. This study tested the acceptability and effectiveness of an eHealth universal program for students and parents to prevent adolescent alcohol use. Methods: A cluster rand...

This study explored age, period, and cohort effects associated with trends in psychological distress and risky alcohol consumption. Data came from 108,536 Australians aged 14-79 years old from birth cohorts between 1925-2005, endorsing past year alcohol use in the 2004-2019 Australian National Drug Strategy Household Surveys. Risky alcohol consumpt...

Background: Alcohol use is a leading risk factor for death and disability worldwide. Aims: We conducted a systematic review on the cost-effectiveness evidence for interventions to prevent alcohol use across the lifespan. Method: Electronic databases (EMBASE, Medline, PsycINFO, CINAHL and EconLit) were searched for full economic evaluations and...

This study aimed to examine the effect of a personality-targeted prevention program (Preventure) on trajectories of general and specific dimensions of psychopathology from early- to mid-adolescence. Australian adolescents (N = 2190) from 26 schools participated in a cluster randomized controlled substance use prevention trial. This study compared s...

Background: Internalizing and externalizing personality traits are robust risk factors for substance use and mental health, and personality-targeted interventions are effective in preventing substance use and mental health problems in youth. However, there is limited evidence for how personality relates to other lifestyle risk factors, such as ene...

There is a significant degree of heterogeneity in scales that purport to measure depression and generalized anxiety in adolescent samples, which makes it difficult to directly compare scores across studies. The aim of the current study is to develop a common metric that facilitates the comparison of scores from different but related scales of depre...

Background: Parents play an influential role in the health behaviors of their children, such as physical activity, dietary intake, sleep, screen time, and substance use. However, further research is needed to inform the development of more effective and engaging parent-based interventions targeting adolescent risk behaviors. Objective: This stud...

Background: Lifestyle risk behaviours are prevalent among adolescents and commonly co-occur, but current intervention approaches tend to focus on single risk behaviours. This study aimed to evaluate the efficacy of the eHealth intervention Health4Life in modifying six key lifestyle risk behaviours (ie, alcohol use, tobacco smoking, recreational sc...

Background: Moderate alcohol consumption appears to be associated with reduced inflammation. Determining whether this association is robust to common variations in research parameters has wide-reaching implications for our understanding of disease aetiology and public health policy. We aimed to conduct comprehensive multiverse and vibration of eff...

Objective: Moderate alcohol consumption is associated with decreased risk for depression, but it remains unclear whether this is a causal relationship or a methodological artifact. To compare the effects of consistent abstinence and occasional, moderate, and above-guideline alcohol consumption throughout early to middle adulthood on depression at a...

Introduction: The COVID-19 pandemic introduced a unique concern regarding the potential for pandemic-related increases in alcohol use. However, most studies which have measured pandemic-related changes to date utilise self-attribution measures of changes in alcohol use using cross-sectional designs, which rely on accurate self-attributions for val...

This study aimed to investigate the long-term patterns and predictors of heroin use, dependence, and psychiatric health over 18–20 years among a cohort of Australians with heroin dependence, using a prospective longitudinal cohort study conducted in Sydney, Australia. The original cohort consisted of 615 participants, who were followed up at 3 mont...

Background Disadvantage and transgenerational trauma contribute to Aboriginal and Torres Strait Islander (Indigenous) Australians being more likely to experience adverse health consequences from alcohol and other drug use than non-Indigenous peoples. Addressing these health inequities requires local monitoring of alcohol and other drug use. While c...

Importance Alcohol consumption is one of the leading preventable causes of burden of disease worldwide. Selective prevention of alcohol use can be effective in delaying the uptake and reducing harmful use of alcohol during the school years; however, little is known about the durability of these effects across the significant transition from early a...

Several universal school-based prevention programs, notably the Australian Climate Schools program, have proven efficacious at reducing and maintaining a lower level of harmful alcohol consumption relative to a control condition. Yet, there are limited studies investigating the potential mechanisms that account for the reduction in harmful alcohol...

Introduction: Trauma exposure among clients of substance use treatment services is almost universal and rates of trauma-related symptoms are correspondingly high. This study examined one aspect of clinical care-clinical documentation-and sought to systematically assess the documentation of trauma-related comorbidities and their treatment in a subs...

Introduction and Aims: Trauma-related comorbidities are extremely prevalent in substance use treatment settings. Advancements in the field have seen the establishment of complex post-traumatic stress disorder (CPTSD) as a new diagnosis in the International Classification of Diseases, 11th Revision; however, there is no available evidence to inform...

Aims: To examine age, period, and birth cohort trends in the prevalence of any alcohol-related risky behaviour, and to compare these trends between men and women. Design and setting: Age, period, cohort analysis of repeated cross-sectional survey data from the Australian National Drug Strategy Household Survey from 2001 to 2016. Participants:...

BACKGROUND Parents play an influential role in the health behaviors of their children, such as physical activity, dietary intake, sleep, screen time, and substance use. However, further research is needed to inform the development of more effective and engaging parent-based interventions targeting adolescent risk behaviors. OBJECTIVE This study ai...

Lifestyle risk behaviors often co-occur and are prevalent among adolescents. Parent-based interventions addressing risk behaviors concurrently have the potential to improve youth and parent outcomes. This systematic review evaluated the efficacy of parent-based interventions targeting multiple lifestyle risk behaviors among adolescents and parents....

Several universal school-based prevention programs, notably the Australian Climate Schools program, have proven efficacious at reducing and maintaining a lower level of harmful alcohol consumption relative to a control condition. Yet, there are limited studies investigating the potential mechanisms that account for the reduction in harmful alcohol...

Background: Moderate alcohol consumption appears to be associated with reduced inflammation compared to abstinence. However, there are concerns about the impact of common variations in researcher-defined data processing and analysis parameters on this relationship. In light of this, we performed comprehensive multiverse and vibration of effects ana...

Purpose Lesbian, gay, and bisexual (LGB) individuals, and LB women specifically, have an increased risk for psychiatric morbidity, theorized to result from stigma-based discrimination. To date, no study has investigated the mental health disparities between LGB and heterosexual AQ1individuals in a large cross-national population-based comparison. T...

Background Lifetime trajectories of mental ill-health are often established during adolescence. Effective interventions to prevent the emergence of mental health problems are needed. In the current study we assessed the efficacy of the cognitive behavioural therapy (CBT)-informed Climate Schools universal eHealth preventive mental health programme,...

Background and aims: Tolerance to the effects of alcohol is an important element in the diagnosis of alcohol use disorders (AUD); however, there is ongoing debate about its utility in the diagnosis AUD in adolescents and young adults. This study aimed to refine the assessment of tolerance in young adults by testing different definitions of toleran...

Aim Exposure to traumatic events (TEs) is associated with substance use disorders (SUDs). However, most studies focus on a single TE, and are limited to single countries, rather than across countries with variation in economic, social and cultural characteristics. We used cross-national data to examine associations of diverse TEs with SUD onset, an...

Background: Supply of alcohol to adolescents is associated with increased alcohol consumption and harms including alcohol use disorder (AUD). We aimed to identify: (1) trajectories of alcohol supply to adolescents; (2) sociodemographic characteristics associated with supply trajectory; (3) patterns of alcohol consumption by supply trajectory; and...

Patient‐reported helpfulness of treatment is an important indicator of quality in patient‐centered care. We examined its pathways and predictors among respondents to household surveys who reported ever receiving treatment for major depression, generalized anxiety disorder, social phobia, specific phobia, post‐traumatic stress disorder, bipolar diso...

Background The COVID‐19 pandemic has resulted in disruptions across many life domains. The distress associated with the pandemic itself, and with public health efforts to manage the outbreak, could result in increased alcohol use. This study aimed to quantify changes in alcohol use during the early stages of the pandemic and factors associated with...

BACKGROUND Physical inactivity is a preventable risk factor for several chronic diseases and one of the driving forces behind the growing global burden of disease. Recent evidence has shown that interventions using mobile smartphone applications (apps) can promote a significant increase in physical activity (PA) levels. However, the accuracy and re...

Background Physical inactivity is a preventable risk factor for several chronic diseases and one of the driving forces behind the growing global burden of disease. Recent evidence has shown that interventions using mobile smartphone apps can promote a significant increase in physical activity (PA) levels. However, the accuracy and reliability of us...

Objective Physical inactivity, sugar sweetened beverage consumption, alcohol use, smoking, poor sleep and excessive recreational screen time (the ‘Big 6’ lifestyle risk behaviours) often co-occur and are key risk factors for psychopathology. However, the best fitting latent structure of the Big 6 is unknown and links between multiple lifestyle risk...

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a quantitative nosological system that addresses shortcomings of traditional mental disorder diagnoses, including arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, substantial heterogeneity within disorders, and diagnostic unreliability over time and...

Background Research has long found ‘J-shaped’ relationships between alcohol consumption and certain health outcomes, indicating a protective effect of moderate consumption. However, methodological limitations in most studies hinder causal inference. This review aimed to identify all observational studies employing improved approaches to mitigate co...

The Australian Government will set the direction for addressing road safety over the next decade with its 2021–2030 National Road Safety Strategy. This road map will detail objectives and goals agreed upon by all Australian states and territories. Similar to previous national strategies, Aboriginal and Torres Strait Islander (Indigenous) Australian...

Background Different forms of alcohol‐related harm (e.g., hangovers, fighting) may confer differential risk of clinically relevant alcohol problems. We examine: (i) patterns of transition in experiencing alcohol‐related harms across adolescence; (ii) whether factors in early adolescence predict transition patterns; and (iii) whether transition patt...

Aim We examined prevalence and factors associated with receiving perceived helpful alcohol use disorder (AUD) treatment, and persistence in help-seeking after earlier unhelpful treatment. Methods Data came from 27 community epidemiologic surveys of adults in 24 countries using the World Health Organization World Mental Health surveys (n = 93,843)....

Importance: Prevention of depressive symptoms and disorders is a key public health priority but requires an improved understanding of modifiable risk and protective factors. A salient unanswered question in this context is whether the apparent protective effect of alcohol against depression may be causal.Objective: To compare the effects of consist...

Background. Lifetime trajectories of mental ill health are often established during adolescence. Effective interventions to prevent the emergence of mental health problems are needed. In the current study we assessed the efficacy of the CBT informed Climate Schools universal eHealth preventive mental health program, relative to a control. We also e...

Background Alcohol Use Disorder (AUD) is a significant contributor to global disease burden. AUD has a relatively early onset during young adulthood (Teesson et al., 2010). However, compared to AUD in adults, we have relatively little understanding of AUD in adolescents and emerging adults. Methods The RADAR study is a prospective cohort study des...

Objective Alcohol use is a leading cause of burden of disease among young people. Prevention strategies can be effective in the short-term, however little is known about their longer-term effectiveness. The aim of this study was to examine the sustainability of universal, selective and combined alcohol use prevention across the critical transition...

Objective: To synthesise international findings on the alcohol-dementia relationship and provide a cross-national comparison of the alcohol-dementia relationship with critical evidence for the relationship between alcohol use and dementia in under-studied populations. Design and setting: Individual participant data meta-analysis of 15 prospective e...

Background An emerging body of literature has indicated that broad, transdiagnostic dimensions of psychopathology are associated with alterations in brain structure across the life span. The current study aimed to investigate the relationship between brain structure and broad dimensions of psychopathology in the critical preadolescent period when p...

Background Early adolescence is a challenging transition period where mental ill-health and experimentation with alcohol and tobacco often increases. Some foods and eating behaviours can be addictive in a way that is comparable to addictive substances. Few studies have examined the prevalence of food addiction in young people, and none have measure...

Background Adolescents often display heterogenous trajectories of alcohol use. Initiation and escalation of drinking may be an important predictor of later harms. Previous attempts to conceptualise these trajectories lacked adjustment for known confounders of adolescent drinking, which our study has aimed to address by modelling dynamic changes in...

Background Physical inactivity, poor diet, sedentary recreational screen time, poor sleep, alcohol use and smoking (the “Big 6”) are key lifestyle risk factors for chronic disease. The Big 6 typically emerge during adolescence, co-occur and continue into adulthood. To improve short- and long-term health, early and effective prevention is critical....

Focus of Presentation Research has long found ‘J-shaped’ relationships between alcohol consumption and certain health outcomes, indicating a protective effect of moderate consumption. However, methodological limitations in most studies hinder causal inference. While enhanced methods for data analysis (e.g. G-methods) and alternative observational d...

This is the first study to investigate the effectiveness of Preventure, a selective personality-targeted prevention program, in reducing the uptake of tobacco smoking over a three-year period in adolescence. A cluster randomised controlled trial was conducted to assess the effectiveness of Preventure. Schools were block randomised to either the Pre...

Background: Parents are the main supplier of alcohol to children but it is not known whether mothers and fathers equally contribute to the supply of alcohol to their female and male children as these children transition to adulthood. Objectives: i) to determine whether the gender of the parent is associated with the gender of the adolescent offspri...

Background: Treatment guidelines for generalized anxiety disorder (GAD) are based on a relatively small number of randomized controlled trials and do not consider patient-centered perceptions of treatment helpfulness. We investigated the prevalence and predictors of patient-reported treatment helpfulness for DSM-5 GAD and its two main treatment pa...

(1) Background: More time spent on social media has been linked to increased alcohol use, with exposure to peer alcohol-related content on social media (content exposure) named as a critical factor in this relationship. Little is currently known about whether early content exposure may have lasting effects across adolescent development, or about th...

Aims To estimate change in young people's alcohol consumption during COVID-19 restrictions in Australia in early-mid 2020, and test whether those changes were consistent by gender and level of consumption prior to the pandemic. Design Prospective longitudinal cohort Setting Secondary schools in New South Wales, Tasmania, and Western Australia. P...

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirical effort to address limitations of traditional mental disorder diagnoses. These include arbitrary boundaries between disorder and normality, disorder co‐occurrence in the modal case, heterogeneity of presentation within dis­orders, and instability of diagnosis within patients. This...

Background Suicide plans and attempts rarely occur without prior suicidal ideation but are hard to predict. Early intervention efforts need to focus on subgroups of the population who are more likely to transition from ideation to suicidal plans and attempts. The current study utilised data from a large nationally representative sample to investiga...

Research has long found ‘J-shaped’ relationships between alcohol consumption and certain health outcomes, indicating a protective effect of moderate consumption. However, methodological limitations in most studies hinder causal inference. This review aimed to identify all observational studies employing improved approaches to mitigate confounding i...

Introduction There is a substantial literature finding that moderate alcohol consumption is protective against certain health conditions. However, more recent research has highlighted the possibility that these findings are methodological artefacts, caused by confounding and other biases. While modern analytical and study design approaches can miti...

Much of the knowledge about the relationships among domains of psychopathology is built on the diagnostic categories described in the Diagnostic and Statistical Manual of Mental Disorders ( DSM), and relatively little research has examined the symptom-level structure of psychopathology. The aim of this study was to delineate a detailed hierarchical...

Background: Poor diet, alcohol use, and tobacco smoking have been identified as strong determinants of chronic diseases, such as cardiovascular disease, diabetes, and cancer. Smartphones have the potential to provide a real-time, pervasive, unobtrusive, and cost-effective way to measure these health behaviors and deliver instant feedback to users....

Background and aims Experience of alcohol‐induced memory blackouts in adolescence may be an important risk factor for later harms. This longitudinal study i) modelled trajectories of alcohol‐related blackouts throughout adolescence, ii) explored early‐adolescent predictors of blackout trajectories, and iii) examined the association between blackout...