Behavioral activation (BA) interventions systematically encourage positive and value-based activities. Engaging in them is an effective way to counteract negative affect, but it is unknown whether there are subtypes of activities that may have differential effects on mood. This study investigated the factorial structure of 99 potentially rewarding activities used in an online BA intervention during the COVID-19 lockdown. About 3624 German-speaking participants evaluated a list of 99 activities that were easy to apply. We analyzed the initially 99 activities by means of confirmatory factor analysis. Since activities can either be seen as reflective or formative indicators, a reflective as well as a formative model was analyzed. Although the range of chosen activities differed clearly between respondents, a one-factor model provided the best fit. It seems that a general "activity" factor is more important for explaining whether people choose a certain activity or not, than specific characteristics of the activity itself.
Keywords: behavioral activation; mental health; ordinal factor analysis; positive activities; reflective vs formative measurement.