Using random forest to identify correlates of depression symptoms among adolescents.

PURPOSE: Adolescent depression is a significant public health concern, and studying its multifaceted factors using traditional methods possess challenges. This study employs random forest (RF) algorithms to determine factors predicting adolescent depression scores. METHODS: This study utilized self-reported survey data from 56,008 Canadian students (grades 7-12) attending 182 schools during the 2021/22 academic year. RF algorithms were applied to identify the correlates of (i) depression scores (CESD-R-10) and (ii) presence of clinically relevant depression (CESD-R-10 ≥ 10). RESULTS: RF achieved a 71% explained variance, accurately predicting depression scores within a 3.40 unit margin. The top 10 correlates identified by RF included other measures of mental health (anxiety symptoms, flourishing, emotional dysregulation), home life (excessive parental expectations, happy home life, ability to talk to family), school connectedness, sleep duration, and gender. In predicting clinically relevant depression, the algorithm showed 84% accuracy, 0.89 sensitivity, and 0.79 AUROC, aligning closely with the correlates identified for depression score. CONCLUSION: This study highlights RF's utility in identifying important correlates of adolescent depressive symptoms. RF's natural hierarchy offers an advantage over traditional methods. The findings underscore the importance and additional potential of sleep health promotion and school belonging initiatives in preventing adolescent depression.

Label Accuracy of Legal Oral Cannabis Oil Products in Ontario, Canada.

This case series compares amounts of tetrahydrocannabinol and cannabidiol reported on product labels vs levels found in laboratory testing in legal oral cannabis oil products in Ontario, Canada.

Dementia resources for eating, activity, and meaningful inclusion (DREAM) toolkit co-development: process, output, and lessons learned.

Promoting wellbeing of persons with dementia and their families is a priority of research and practice. Engaging diverse partners, including persons with dementia and their families, to co-develop interventions promotes relevant and impactful solutions. We describe the process, output, and lessons learned from the dementia resources for eating, activity, and meaningful inclusion (DREAM) project, which co-developed tools/resources with persons with dementia, care partners, community service providers, health care professionals, and researchers with the aim of increasing supports for physical activity, healthy eating, and wellbeing of persons with dementia. Our process included: (1) Engaging and maintaining the DREAM Steering Team; (2) Setting and navigating ways of engagement; (3) Selecting the priority audience and content; (4) Drafting the toolkit; (5) Iterative co-development of tools and resources; (6) Usability testing; and (7) Implementation and evaluation. In virtual meetings, the DREAM Steering Team confirmed the toolkit audiences (primary: community service providers; secondary: persons with dementia and care partners) and identified and evolved content areas. An environmental scan identified few existing, high-quality resources aligned with content areas. The Steering Team, additional multi-perspective partners, and external contractors iteratively co-developed new tools/resources to meet gaps over a 4-month virtual process that included virtual meetings, email exchange of documents and feedback, and one-on-one calls by telephone or email. The final DREAM toolkit includes a website with seven learning modules (on the diversity of dementia, rights and inclusion of persons living with dementia, physical activity, healthy eating, dementia-inclusive practices), a learning manual, six videos, nine handouts, and four wallet cards ( www.dementiawellness.ca ). Our co-development participants rated the process highly in relation to the principles and enablers of authentic partnership even though all engagement was virtual. Through use of the co-developed DREAM toolkit, we anticipate community service providers will gain the knowledge and confidence needed to provide dementia-inclusive wellness programs and services that benefit persons with dementia and their families.

Cannabis Use Frequency and Cannabis-Related Consequences in High-Risk Young Adults Across Cannabis Legalization.

Importance: A key concern about recreational cannabis legalization is increases in use and adverse consequences, particularly among young adults (aged 18-29 years) who have the highest prevalence of cannabis use, and especially in higher-risk, more vulnerable young adults. However, few longitudinal studies have examined patterns of cannabis consumption in high-risk young adults over the course of legalization. Objective: To examine changes in cannabis use frequency and cannabis-related consequences over recreational cannabis legalization in Canada in a longitudinal sample of high-risk young adults. Design, Setting, and Participants: Longitudinal observational cohort study following young adults in Ontario, Canada, aged 19.5 to 23.0 years who reported regular heavy episodic drinking (65% past-month cannabis use) at enrollment. Participants were surveyed every 4 months for 3 years between February 2017 and February 2020 (3 prelegalization waves, 4 postlegalization waves). Data were analyzed from March to May 2023. Exposures: Recreational cannabis legalization in Canada and 4 potential moderators of change: sex, income, education, and prelegalization cannabis use frequency. Main Outcomes and Measures: Cannabis use frequency and cannabis-related adverse consequences. Results: In a cohort of 619 high-risk young adults (baseline mean [SD] age, 21.0 [1.2] years; 346 female participants [55.9%]), omnibus model testing revealed significant overall decreases in both cannabis use frequency (F = 2.276, 3000.96; P = .03) and cannabis-related consequences (F = 10.436, 3002.21; P < .001) over time, but these changes were substantially moderated by prelegalization frequency (frequency: F = 7.5224, 3021.88; P < .001; consequences: F = 7.2424, 2986.98; P < .001). Follow-up tests showed individuals who used cannabis more frequently prelegalization significantly decreased their use and cannabis-related consequences postlegalization. In contrast, individuals who did not use cannabis prelegalization exhibited a small magnitude increase in frequency over time but nonsignificant changes in cannabis-related consequences. Sex, income, and education did not moderate changes over time. Conclusions and Relevance: In this cohort study of high-risk young adults, individuals using cannabis frequently prelegalization showed significant reductions in use and consequences over time, reflecting an aging out pattern. Small increases in use among participants with no prelegalization use were observed over time, but without parallel changes in cannabis-related consequences. The results did not reveal substantive adverse near-term outcomes across the legalization period, although a within-participants design cannot rule out the possibility of alternative trajectories in the absence of legalization.

Using classification and regression trees to model missingness in youth BMI, height and body mass data. / Utilisation des arbres de classification et de régression pour modéliser les données manquantes sur l'IMC, la taille et la masse corporelle chez les jeunes.

INTRODUCTION: Research suggests that there is often a high degree of missingness in youth body mass index (BMI) data derived from self-reported measures, which may have a large effect on research findings. The first step in handling missing data is to examine the levels and patterns of missingness. However, previous studies examining youth BMI missingness used logistic regression, which is limited in its ability to discern subgroups or identify a hierarchy of importance for variables, aspects that may go a long way in helping understand missing data patterns. METHODS: This study used sex-stratified classification and regression tree (CART) models to examine missingness in height, body mass and BMI data among 74 501 youth participating in the 2018/19 COMPASS study (a prospective cohort study examining health behaviours among Canadian youth), where 31% of BMI data were missing. Diet, movement, academic, mental health and substance use variables were examined for associations with missingness in height, body mass and BMI. RESULTS: CART models indicated that the combination of being younger, having a selfperception of being overweight, being less physically active and having poorer mental health yielded female and male subgroups highly likely to be missing BMI values. Survey respondents who did not perceive themselves as overweight and who were older were unlikely to be missing BMI values. CONCLUSION: The subgroups identified by the CART models indicate that a sample that deletes cases with missing BMI would be biased towards physically, emotionally and mentally healthier youth. Given the ability of CART models to identify these subgroups and a hierarchy of variable importance, they are an invaluable tool for examining missing data patterns and appropriate handling of missing data.

Shifting school health priorities pre-post cannabis legalization in Canada: Ontario secondary school rankings of student substance use as a health-related issue.

This study examined how schools prioritize ten key health concerns among their student populations over time and whether schools' prioritization of alcohol and other drug use (AODU) corresponds to students' substance use behaviours and cannabis legalization as a major policy change. Data were collected from a sample of secondary schools in Ontario, Canada across four years (2015/16-2018/19 [N2015/16 = 65, N2016/17 = 68, N2017/18 = 61 and N2018/19 = 60]) as a part of the COMPASS study. School-level prevalence of cannabis and alcohol use between schools that did and did not prioritize student AODU as a health concern was examined. Ordinal mixed models examined whether student cannabis and alcohol use were associated with school prioritization of AODU. Chi-square tests examined changing health priorities among schools pre-post cannabis legalization. School priority ranking for AODU was mostly stable over time. While AODU was identified as an important health concern, most schools identified mental health as their first priority across the four years of the study. No significant changes to school AODU priorities were observed pre-post cannabis legalization nor was school prioritization of AODU associated with student cannabis and alcohol use behaviours. This study suggests that schools may benefit from guidance in identifying and addressing priority health concerns among their student population.

Learning from missing data: examining nonreporting patterns of height, weight, and BMI among Canadian youth.

BACKGROUND: Youth body mass index (BMI), derived from self-reported height and weight, is commonly prone to nonreporting. A considerable proportion of overweight and obesity (OWOB) research relies on such self-report data, however little literature to date has examined this nonreporting and the potential impact on research conclusions. The objective of this study was to examine the characteristics and predictors of missing data in youth BMI, height, and weight. METHODS: Using a sample of 74,501 Canadian secondary school students who participated in the COMPASS study in 2018/19, sex-stratified generalized linear mixed models were run to examine predictors of missing data while controlling for school-level clustering. RESULTS: In this sample, 31% of BMI data were missing. A variety of diet, exercise, mental health, and substance use variables were associated with BMI, height, and weight missingness. Perceptions of being overweight (females: 95% CI (1.42,1.62), males: 95% CI (1.71,2.00)) as well as intentions to lose weight (females: 95% CI (1.17,1.33), males: 95% CI (1.13,1.32)) were positively associated with BMI missingness. CONCLUSIONS: Findings from this study suggest that nonreporting in youth height and weight is likely somewhat related to the values themselves, and hint that social desirability may play a substantial role in nonreporting. The predictors of missingness identified in this study can be used to inform future studies on the potential bias stemming from missing data and identify auxiliary variables that may be used for multiple imputation approaches.

Patterns of Cannabis Use among Canadian Youth over Time; Examining Changes in Mode and Frequency Using Latent Transition Analysis.

Background: Historically substance use literature has focused on smoking as the main mode of cannabis consumption, so there are knowledge gaps surrounding current understanding of edibles and vaping. These alternative modes of cannabis use are already common among Canadian youth; however, little is known about how these cannabis use patterns change over time. Methods: This study examined the mode (smoking, eating/drinking, vaping) and frequency of cannabis use among a large sample of Canadian youth who participated in 2017-2018 and 2018-2019 data collection waves of the COMPASS study. Using latent transition analysis, this sample consisting of 18,824 youth in grades 9-12 were categorized into cannabis use classes stratified by sex, and their transition between these classes over the one-year period was examined. Results: Three cannabis use classes were identified (occasional multimode, regular multimode, and smoking) alongside one nonuse class. Among youth who reported cannabis use at baseline, transitioning to a multimode group, and/or increasing frequency of multimode use was likely over the one-year period. Conclusions: These findings may highlight a key leverage point for harm-reduction strategies which aim to prevent cannabis related harms associated with high frequency use.

Assessing the impact of sports and recreation facility density within school neighbourhoods on Canadian adolescents' substance use behaviours: quasi-experimental evidence from the COMPASS study, 2015-2018.

OBJECTIVES: There has been relatively little exploration to date of potential protective effects within school neighbourhoods, such as those conferred by facilities that seek to promote health with respect to substance use and related harms. This study examined how the density of sports and recreation facilities in the school neighbourhood is associated with the likelihood of binge drinking, e-cigarette use, cigarette smoking and cannabis use among Canadian secondary school students. DESIGN: Longitudinal data from the COMPASS study on Canadian youth health behaviours from 2015/2016 to 2017/2018 was linked with school neighbourhood data capturing the number of sports and recreation facilities within a 1500 m radius of schools. SETTING: Secondary schools and school neighbourhoods in Alberta, British Columbia, Ontario and Quebec who participated in the COMPASS study. PARTICIPANTS: 16 471 youth who participated in the COMPASS study over three school years (2015/2016-2017/2018). PRIMARY AND SECONDARY OUTCOME MEASURES: Binge drinking, e-cigarette use, cigarette use, cannabis use. RESULTS: Logistic regression models using generalised estimating equations identified that greater density of sports and recreation facilities within the school neighbourhood was significantly associated with lower likelihood of binge drinking and e-cigarette use but was not associated with cigarette smoking or cannabis use. CONCLUSIONS: This research can help to support evidence-informed school community-based efforts to prevent substance-related harms among youth.

Cannabis Use, Screen Time, and Internalizing Symptoms among Canadian Youth: Testing Mediation Pathways.

Background: Existing research suggests positive correlations between screen time sedentary behaviors (STSB) and substance use, including cannabis use, among youth. However, little research has examined what factors mediate these relationships.Methods: This study examined mediating pathways among STSB, internalizing symptoms (IS), and cannabis use in a linked longitudinal sample of 28 269 Canadian youth who participated in the COMPASS study over a two-year period (2017/18 to 2018/19). Structural equation modeling examined two main hypotheses cross-sectionally and over time: 1) if IS mediated associations between STSB and cannabis use frequency, and 2) if STSB mediated associations between IS and cannabis use frequency. Results: Results demonstrated significant partial mediation effects for both hypotheses. For example, indirect effects indicated that IS mediated the association between STSB and cannabis use both cross sectionally (95% CI: 0.021, 0.029) and longitudinally (95% CI: 0.006, 0.010). STSB also mediated associations between IS and cannabis use cross sectionally (95% CI: 0.015, 0.023) and longitudinally (95% CI: 0.010, 0.014). This study demonstrated that the associations between STSB, internalizing symptoms and cannabis use are complex, involving mediation in both directions.Discussion: These findings can be used to inform public health initiatives that aim to take a comprehensive approach to addressing negative health behaviors and outcomes, as it is clear that the multi-directional relationships between STSB and mental health may in-turn impact other health behaviors. Future research should continue to examine mediating factors between STSB and substance use among youth, including exploration of associations with other substances.Supplemental data for this article is available online at https://doi.org/10.1080/10826084.2021.1922455 .

Examining the association between exposure to various screen time sedentary behaviours and cannabis use among youth in the COMPASS study.

BACKGROUND: Canadian youth are among the top users of cannabis globally. The Canadian federal government identified protecting youth from cannabis-related harms as a key public health objective aligned with the legalization and strict regulation of cannabis. While there are well-established associations between screen time sedentary behaviour (STSB) and alcohol and tobacco use, the association with cannabis use is understudied. The purpose of this study is to examine the association between various types of STSBs and cannabis use in a large sample of Canadian youth. METHODS: Using cross-sectional data from 46,957 grade 9 to 12 students participating in year 5 of the COMPASS host study (2016-2017), four gender-stratified ordinal logistic regression models were used to examine how total STSB and four different types of STSBs (watching/streaming TV shows/movies, playing video games, Internet use, emailing/messaging/texting) are associated with frequency of cannabis use. RESULTS: One-quarter of participants (24.9%) reported using cannabis in past 12 months; the largest proportion of this group (37.9%) reported rare/sporadic use. Overall, participants spent an average 7.45 ( ±5.26) hours/day on STSBs. Total STSB was positively associated with more frequent cannabis use, and when separated by type, internet use and messaging were significant. Playing video games and watching TV/movies were also significantly associated with more frequent cannabis use, but only for females. CONCLUSIONS: The associations between frequency of cannabis use and various measures of STSBs suggest that screen time may be a risk factor for cannabis use among youth. This association may be mediated by youths' mental wellbeing, given emerging evidence that STSB is a risk factor for poor mental health, and the tendency for individuals to use substances as a coping mechanism. Further, the ubiquity of pro-substance use content on the internet may also contribute to increased exposure to and normalization of cannabis, further promoting its use.

Youth consumption of alcohol mixed with energy drinks in Canada: Assessing the role of energy drinks.

Consuming alcohol mixed with energy drinks (AmED) is a risk behaviour among youth, and previous research has reported a positive association between binge drinking and AmED consumption. However, limited research has examined how regular consumption of energy drinks is associated with AmED consumption among youth. The purpose of this report is to examine the role of energy drink use on AmED consumption in a Canadian youth population. Using data from the 2015-2016 COMPASS survey including 35,300 grade 9 to 12 students, two logistic regression models investigated if the inclusion of energy drink consumption in the past week altered the results of a model examining AmED consumption. In this sample, 13.2% of students reported AmED consumption in the last 12 months. Those who reported drinking energy drinks in the past week were 3.38 times more likely to consume AmED than those who did not drink energy drinks. The inclusion of past week energy drink use decreased the effect size of other associated substance use behaviours. This report demonstrates that past week energy drink use is associated with increased likelihood of AmED consumption and suggests that previous research may have missed this important contributor. These findings along with existing energy drink research highlight the importance of addressing the lack of energy drink regulations in Canada.