Objective: This study (1) describes the distribution of Kessler Psychological Distress Scale (K6) scores in an epidemiological sample of youth, (2) reports its item correlations and internal consistency reliability, (3) tests for measurement invariance by age (youth vs. adults) and sex, and (4) examines its predictive power for past-year psychiatric disorders. Method: Youth aged 15 to 19 years ( n = 2010) and adults aged 20 to 64 years ( n = 2010) from the Canadian Community Health Survey–Mental Health who completed the K6 were included. Past-year psychiatric disorders were measured using the World Health Organization Composite International Diagnostic Interview 3.0 (WHO-CIDI). Polychoric correlation matrices and ordinal reliability coefficients were calculated to assess internal consistency of the K6, and confirmatory factor analysis was used to test for measurement invariance. Area under the curves (AUCs) were computed to determine the extent to which the K6 predicted a positive screen on the WHO-CIDI. Results: K6 scores showed a J-shaped distribution, with >50% of youth having scores ≤3. Item and total scores were higher for females versus males. Item correlations were robust (0.31-0.78) and internal consistency was high (α = 0.86). Full measurement invariance was demonstrated between youth and adults, as well as between male and female youth. The K6 was a strong predictor of major depressive episode (AUC = 0.848), generalized anxiety disorder (AUC = 0.847), and bipolar disorder (AUC = 0.853). Conclusions: The K6 is a valid and reliable measure of psychological distress among youth. Its brevity and robust predictive power for psychiatric disorder confirm its utility in clinical and community settings to identify youth needing comprehensive psychiatric assessment.

The aims of this study were to estimate the: (1) 12-mo prevalence of suicidal thoughts, plans, and attempts in a population sample of adolescents and young adults with and without chronic illness; (2) associations among chronic illness and suicidal thoughts and behaviour (STB); and, (3) moderating roles of mood and substance use disorder on this association. Individuals were aged 15 to 30 y (n = 5,248) from the Canadian Community Health Survey-Mental Health. Twelve-month STB and psychiatric disorder were measured using the World Health Organization Composite International Diagnostic Interview 3.0. Multinomial logistic regression examined associations between chronic illness and STB, adjusting for relevant sociodemographic and health characteristics. Product term interactions among chronic illness, mood, and substance use disorders were included in the regression models to examine potential moderating effects. Prevalence of suicidal thoughts, plans, and attempts was higher in individuals with chronic illness (P < 0.01 for all). After adjustment, chronic illness increased the odds for suicidal thoughts [OR = 1.28 (1.01 to 1.64)], plans [OR = 2.34 (1.22 to 4.39)], and attempts [OR = 4.63 (1.52 to 14.34)]. In the presence v. absence of a mood disorder, the odds for suicidal thoughts were higher among individuals with chronic illness [OR = 1.89 (1.06 to 5.28)]. Suicidal thoughts and behaviours are common among adolescents and young adults with chronic illness, particularly among those with comorbid mood disorders. Health professionals should routinely ask about STB during assessments of their adolescent and young adult patients.

Our aim was to examine measurement invariance of the Flourishing Scale (FS)—a concise measure of psychological wellbeing—across two study samples and by population characteristics among Canadian adolescents. Data were retrieved from 74,501 Canadian secondary school students in Year 7 (2018–2019) of the COMPASS Study and from the original validation of the FS (n = 689). We assessed measurement invariance using a confirmatory factor analysis in which increasingly stringent equality constraints were specified for model parameters between the following groups: study sample (i.e., adolescents vs. adults), gender, grade, and ethno-racial identity. In all models, full measurement invariance of the FS across all sub-groups was demonstrated. Our findings support the validity of the FS for measuring psychological wellbeing among Canadian adolescents in secondary school. Observed differences in FS score among subgroups therefore represent true differences in wellbeing rather than artifacts of differential interpretation.

Introduction Multimorbidity, the co-occurrence of a chronic physical condition and mental disorder, affects a substantial number of children and youth and can lead to compromised quality of life, hardship for families, and an increased burden on the healthcare system. We are conducting a study to document the course of mental disorder in children and youth diagnosed with a chronic physical condition; identify predictors of child and youth multimorbidity; examine whether the effects of these predictors are moderated by relevant psychosocial and biological factors; explore potential inflammatory and stress biomarkers that mediate the onset of child and youth multimorbidity; and, assess whether multimorbidity in children and youth alters patterns of mental health service use. Methods and analysis Multimorbidity in Children and Youth Across the Life-course (MY LIFE) is a prospective study. Two hundred and fifty children and youth aged 2–16 years diagnosed with a chronic physical condition along with one parent will be recruited from the outpatient clinics at a paediatric tertiary care centre. Data will be collected using a multi-informant, multimethod design at four time-points (at recruitment, and at 6, 12 and 24 months postrecruitment). Parents will provide reports for all children/youth. In addition, youth ≥10 years will self-report. Mental disorder will be assessed using structured interviews. On completion of data collection, participant-reported data will be linked to provincial health records to identify mental health services use. Multilevel analyses (survival, proportional hazard, structural equation modelling) will be used to address MY LIFE objectives. Ethics and dissemination This study has been approved by the University of Waterloo Human Research Ethics Board and the Hamilton Integrated Research Ethics Board. Findings will be disseminated to key stakeholders using a number of outlets (peer-reviewed publications and conferences, lay informational pamphlets, social media).

Objectives: To examine the effectiveness of group cognitive behavioural therapy (CBT) for postpartum depression (PPD) delivered by public health nurses with little to no previous psychiatric training at improving depression, worry, social support and the mother-infant relationship. Methods: Mothers (n = 141) living in Ontario, Canada with Edinburgh Postnatal Depression Scale Scores ≥10 and an infant <12 months of age were randomized to receive nine weekly 2-h sessions of in-person group CBT for PPD delivered by two public health nurses plus treatment as usual (TAU; experimental group) or TAU alone (control group). Primary outcomes were change in EPDS score and current major depressive disorder (Mini International Neuropsychiatric Interview) assessed immediately post-treatment (T2). Secondary outcomes included maternal worry, social support, and quality of the mother-infant relationship. All outcomes were assessed again six months post-treatment (T3). Results: Participants in the experimental group had statistically significantly greater reductions in PPD symptoms immediately post-treatment (T2) (B = -5.35, p < 0.01), were more likely to manifest a clinically significant improvement in EPDS scores (≥4 points; OR = 3.44, 95%CI: 1.49–7.94), and no longer have symptoms consistent with current MDD (OR = 5.31, 95% CI: 1.78–15.83). Six months post-treatment (T3), experimental group participants had higher odds of clinically significant PPD improvement (OR = 5.10, 95%CI: 1.89–13.78), while 25% of the experimental group and 70% of remaining control group participants reported current MDD ( p < 0.01). Statistically significant improvements in worry and the mother-infant relationship were also observed, decreases maintained at six months post-treatment. Conclusions: Public health nurses with little to no previous psychiatric training can be trained to deliver effective group CBT for PPD to improve depression, worry, and the mother-infant relationship. Task shifting PPD treatment with group CBT to public health nurses could improve treatment uptake and lead to better outcomes for mothers, families, and the healthcare system. (Trial Registration NCT03039530)