Given the increasing interest in meta-analyses of Single-Case Experimental Design (SCED) studies mainly in the fields of behavioral, communication disorders, educational, and rehabilitation research, the aim of the present review is to determine the general characteristics of these meta-analyses, namely design characteristics, the kind of data provided in the primary studies and the ones included in meta-analyses, and the type of analyses that were conducted. In this review, 178 meta-analyses were examined for these characteristics. The results indicate that the number of SCED meta-analyses has increased remarkably in recent years. The most frequently used effect size metric was the percentage of non-overlapping data (PND) and the most commonly utilized analysis for synthesizing the results of primary SCEDs was a simple average of effect sizes. The current study provides insights in the characteristics of primary SCED studies and SCED meta-analyses, and therefore can help in further developing methodological techniques and in evaluating whether the currently used techniques are in line with the methodological advancements.

Volunteer and career firefighters are at risk of major depressive disorders, posttraumatic stress disorder (PTSD), alcohol use disorder, and other mental health disorders due to the demanding and unpredictable nature of their employment. The mental health risks are exacerbated by the need to work extended hours, night shifts, and/or rotating schedules, or the competing demands of other employment, especially in volunteer firefighters. The mental health disorders and risk factors interact with altered sleeping patterns. In the current study, we examined volunteer and career firefighters regarding the association between mental health and sleep, drawing from a national Canadian mental health survey of 1217 firefighters. Most (69%) of the firefighters reported less than ideal sleep quality and 21% screened positive for clinical insomnia, with no significant difference between volunteer and career subgroups. Firefighters with insomnia had higher odds ratios (OR) and frequencies for PTSD (OR = 4.98), generalized anxiety disorder (OR = 7.15), panic disorder (OR = 6.88), social phobia (OR = 4.98), and major depressive disorder (OR = 7.91), than firefighters without insomnia. The burden of sleep disorders and their association with mental health disorders suggests that sleep should be considered in health monitoring and self-management, environmental design, fire service work-organization policies, and health programming.

To conduct a multilevel meta-analysis of multiple single-case experimental design (SCED) studies, the individual participant data (IPD) can be analyzed in one or two stages. In the one-stage approach, a multilevel model is estimated based on the raw data. In the two-stage approach, an effect size is calculated for each participant and these effect sizes and their sampling variances are subsequently combined to estimate a meta-analytic multilevel model. The multilevel model in the two-stage approach has fewer parameters to estimate, in exchange for the reduction of information of the raw data to effect sizes. In this paper we explore how the one-stage and two-stage IPD approaches can be applied in the context of meta-analysis of single-case designs. Both approaches are compared for several single-case designs of increasing complexity. Through a simulation study we show that the two-stage approach obtains better convergence rates for more complex models, but that model estimation does not necessarily converge at a faster speed. The point estimates of the fixed effects are unbiased for both approaches across all models, as such confirming results from methodological research on IPD meta-analysis of group-comparison designs. In light of these results, we discuss the implementation of both methods in R.

Public safety personnel (PSP) are frequently exposed to psychologically traumatic events. The exposures potentiate posttraumatic stress injuries (PTSIs), including posttraumatic stress disorder (PTSD). The Royal Canadian Mounted Police (RCMP) Protocol was designed to mitigate PTSIs using ongoing monitoring and PSP-delivered Emotional Resilience Skills Training (ERST) based on the Unified Protocol for the Transdiagnostic Treatment of Emotional Disorders. The current study pilot-tested ERST effectiveness among diverse PSP. A 16-month longitudinal design engaged serving PSP (n = 119; 34 % female; firefighters, municipal police, paramedics, public safety communicators) who completed PSP-delivered ERST. Participants were assessed for symptoms of PTSIs, including but not limited to PTSD, at pre- and post-training, and 1-year follow-up using self-report measures and clinical interviews. There were reductions in self-report and clinical diagnostic interview positive screens for PTSD and other PTSI from pre- to post-training (ps < 0.05), with mental health sustained or improved at 1-year follow-up. Improvements were observed among firefighters (Cohen's d = 0.40 to 0.71), police (Cohen's d = 0.28 to 0.38), paramedics (Cohen's d = 0.20 to 0.56), and communicators (Cohen's d = 0.05 to 0.14). Ongoing monitoring and PSP-delivered ERST, can produce small to large mental health improvements among diverse PSP, or mitigate PSP mental health challenges, with variations influenced by pre-training factors and organizational supports. ERST replication and extension research appears warranted. Hypotheses Registration: aspredicted.org, #90136. Registered 7 March 2022 - Prospectively registered. ClinicalTrials.gov, NCT05530642.

Royal Canadian Mounted Police (RCMP) are among the public safety sectors reporting the highest exposures to diverse potentially psychologically traumatic events (PPTEs), which contribute to the risk of developing mental health disorders. Current increases in prevalence of mental health disorders among RCMP are substantial and warrant updated prevalence estimates of PPTE exposures. The objective of the present study was to provide updated estimates of lifetime PPTE exposures among RCMP and assess for associations with mental disorders and sociodemographic variables. Participants (n = 1,348) completed a survey assessing self-reported sociodemographic information, PPTE exposures as measured by the Life Events Checklist for the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) Extended, and mental health disorder symptoms. Participants reported exposure to more PPTE types (∼13) than previous samples of RCMP (∼11) and public safety personnel (PSP) (∼11). Prevalence for all the PPTE types was statistically significantly higher for the current sample than previously reported samples of PSP and RCMP, and higher than the Canadian general population. Participants reported highest exposures through any modality (i.e., directly or indirectly) to sudden violent death (98.3%), physical assault (97.9%), serious transport accident (97.0%), sudden accidental death (96.7%), and assault with a weapon (93.7%). Most PPTEs were statistically significantly associated with screening positive for posttraumatic stress disorder, major depressive disorder, generalized anxiety disorder, social anxiety disorder, and panic disorder, but not alcohol use disorder. Increased PPTE exposures reported by current participants compared to a previous sample of RCMP, coupled with the observed associations between PPTE exposures and mental health disorders, highlights the need for further resources and support for RCMP to mitigate and manage the impact of PPTEs. (PsycInfo Database Record (c) 2024 APA, all rights reserved).