Many nuances IWR-1 nmr exist in the complicated relationship between PA and academic performance, and many studies published in the past 5 years continue to find positive effects with one measure or population and no effects in other measures. Different interventions and exposures (sports, PA, vigorous

PA, fitness) continue to have widely varied and sometimes contradicting effects.33 and 36 Studies in the past 5 years have found effects in girls and not boys95 or boys and not girls.35 Additionally, when looking at outcomes, some studies have found effects only with math,41, 57 and 75 only with reading,71 or only with specific components of cognitive tests.61 and 96 Despite these mixed findings, authors often highlight positive outcomes in overall conclusions. The overall increase in positive results may be the results of a trend, intended or not,

towards a positive outcome-reporting bias,97 and 98 where non-significant or negative associations in selected outcome variables are not reported. Including multiple outcome variables in a study increases the likelihood that at least one positive association is found. Based on our examination of the literature, there appears to be an emphasis on positive findings. Additionally, publication bias may also result in researchers not publishing null or negative results.99 While the science on PA and academic achievement Selleckchem Veliparib has made great strides in the past 5 years, plenty of work remains to be done. The large majority of studies continues to be cross-sectional. Almost as many observational studies have been published in the past 5 years as in the previous half-century. With the plethora of observational studies, it is important to note that causal inferences cannot be made from cross-sectional correlations.100 Within observational studies, more studies using prospective cohort designs are needed. Randomized controlled or within-subject Ketanserin designs will continue to provide stronger evidence

of relationships. As mentioned previously, better measures of exposures and outcomes are needed, including objective measures of PA, standardized cognitive testing batteries, and limited self-report of grades. When multiple measures are used, all outcomes should be presented in final results. One way to select outcomes for a study is to work with school administrators and personnel to identify the most appropriate and relevant outcomes. Including school staff in a community participatory research model in all stages of research will help to make study results meaningful to the policymakers the results are intended to reach. In addition to addressing methodological issues, future studies should continue to explore unanswered questions in this area of research.