This study assessed the effectiveness of a strengths-based randomized controlled trial focused on fostering all 24 character strengths in a group of 75 participants from a University in Tunisia. Participants randomly assigned to the challenge condition (n = 40) received an email each day for 24 days, that highlighted a particular strength of the day including why the strength is valuable, how to implement the strength behaviourally, and a motto related to that strength. Those in the control condition (n = 35) simply received emails containing the motto for each strength daily for 24 days. We assessed all participants’ levels of happiness before the experiment (T0), the day following the experiment (T1), and one-month following the experiment (T2). Results from a 2 (group) X 3 (time) split plot ANOVA revealed a significant group-by-time interaction, such that at T2 the experimental group had greater happiness scores than the control group. These findings provide some evidence that even “minimalist” interventions (involving the receipt of emails encouraging character-strength development), might be effective for promoting gains in happiness even one month after the intervention.
