Moderators of the efficacy of a web-based stress management intervention for college students.

High levels of stress are common among college students. Web-based interventions may be one way to teach students stress management skills. Although previous research has demonstrated the overall efficacy of web-based stress management interventions, little attention has been paid to who might benefit most from these interventions. In this study, we analyzed data from 3 prior studies (N = 782) to examine moderators of the efficacy of a web-based stress management intervention that focused on increasing perceived present control (i.e., aspects of stressors that are controllable in the present). Specific moderators assessed in regression analyses were baseline scores on outcome measures (perceived stress, stress symptoms, anxiety, depression) and the putative mechanism (perceived present control) of the intervention. Baseline symptom levels moderated the effects of the intervention on all outcomes, such that the intervention was more effective for students with more baseline symptoms. Baseline levels of present control had less consistent moderating effects, but significant interactions indicated that the intervention was more effective for those with lower levels of present control. The novel Johnson-Neyman technique was used to identify specific cutoff scores on these measures, below which the effect of the intervention was not significant, and scores on the measures associated with varying effect sizes. Findings from the Johnson-Neyman analyses can inform the development of screening criteria for future research and clinical application. Because the intervention was more effective for students with higher levels of baseline distress, it may be better suited for an indicated rather than universal prevention approach. (PsycINFO Database Record (c) 2019 APA, all rights reserved).