A common challenge in developmental research is the amount of incomplete and missing data that occurs from respondents failing to complete tasks or questionnaires, as well as from disengaging from the study (i.e., attrition). This missingness can lead to biases in parameter estimates and, hence, in the interpretation of findings. These biases can be addressed through statistical techniques that adjust for missing data, such as multiple imputation. Although multiple imputation is highly effective, it has not been widely adopted by developmental scientists given barriers such as lack of training or misconceptions about imputation methods. Utilizing default methods within statistical software programs like listwise deletion is common but may introduce additional bias. This manuscript is intended to provide practical guidelines for developmental researchers to follow when examining their data for missingness, making decisions about how to handle that missingness and reporting the extent of missing data biases and specific multiple imputation procedures in publications.

Children and youth with autism spectrum disorder engage in less physical activity than neurotypically developing peers. This may be due to factors associated with autism spectrum disorder at the individual and environmental level that can make physical activity participation more challenging. Parent support is a known determinant of physical activity among children and youth; however, limited research has explored the relationship between parent physical activity support behaviour and child physical activity behaviour within the autism spectrum disorder population. The purpose of this study was to examine the relationship between parent physical activity support behaviour and physical activity levels of children and youth with autism spectrum disorder. Parents (n = 201) of school-aged children and youth with autism spectrum disorder completed measures of parent physical activity support (intentions, behavioural regulation, support behaviour), as well as their child’s physical activity behaviour. The results showed that parent’s intentions to provide physical activity support were associated with their support behaviour for their child’s physical activity (e.g. encouragement, being active together). Parents who followed through with their intentions to provide support reported using behavioural regulation strategies such as goal setting and planning more often. Finally, the results showed parent physical activity support behaviour was positively associated with child physical activity behaviour. Findings suggest parents play an instrumental role in the physical activity behaviour of children and youth with autism spectrum disorder. Family-level interventions targeting parents’ behavioural regulation strategies to provide physical activity support may be an effective strategy to increase physical activity in children and youth with autism spectrum disorder.

Background: Playgrounds provide children with many sensory, motor, and socioemotional experiences that are critical to child development. Unfortunately, playgrounds also represent an environment where children with disabilities experience barriers to accessing play. Structures and materials that are prominently found in almost all playground designs (e.g., swings, slides, sand) can present as obstacles for many children with disabilities to engage in independent play.Aims: This scoping review engaged in the empirical literature to address the research question, “What are the evidence-informed recommendations for designing inclusive playgrounds to enable participation for children with disabilities?” Consideration was given not only to the physical design of playgrounds, but also the playgrounds' surrounding built and social environments.Methods: A systematic search of Medline, PsycINFO, CINAHL, EMBase, ERIC and Scopus was conducted. Only peer-reviewed literature published in English between January 1990 and January 2021, with a primary focus on inclusive playground structure design related to any type of disability were included. Data extraction included the study author(s), year of publication, country of origin, purpose, disability types considered, methods, sample characteristics and key findings. Key findings were synthesized into evidence-informed recommendations, which were later collated, using inductive content analysis, into five broader thematically congruent groups.Results: Thirty-five studies were included using case study (n = 17); observational (n = 6); survey (n = 5); experimental (n = 4); and multiple study (n = 3) designs. Thirteen evidence-based recommendations and one promising practice were categorized into five broad playground elements: entry points; surfacing and paths; features to foster inclusive play; staffing/supervision; and design process.Conclusion: These recommendations build upon previous design-based best-practices that focused exclusively on the physical design of the playground. Our recommendations have implications for how future playgrounds should be designed to maximize usability and inclusiveness and the overall playground experiences for children with disabilities.

Exerting cognitive control results in mental fatigue, which is associated with impaired performance during physical endurance tasks. However, there has been little research on the effects of mental fatigue on people’s perceptions or behaviors involving lifestyle or recreational exercise. The purpose of this study was to examine the effect of mental fatigue on intended physical exertion and exercise performance reflective of current physical activity guidelines. Using a counterbalanced design, participants completed two 50-min experimental manipulations (high vs. low cognitive control exertion) before exercising at a self-selected intensity for 30 min. At visit 1, participants performed a graded exercise task to gain familiarity with a range of exercise intensities and rating of perceived exertion (RPE) while exercising. At visits 2 and 3, participants rated their intended RPE for the exercise session, performed the experimental manipulations, re-rated their intended RPE, and then completed 30-min of exercise on a cycle ergometer. Total work performed while exercising was recorded for each session. Compared with the low cognitive control condition, the high cognitive control manipulation resulted in significantly greater mental fatigue (d = .73), significantly greater reductions in intended RPE (mean difference = –0.62), and significantly less total work (–12.7 kJ) performed during the exercise session. Mental fatigue alters the amount of physical effort people are willing to invest in an exercise workout and follow through with those intentions by doing less work. These are the first results showing people may deliberately adjust their physical effort to cope with mental fatigue.