A major meta-analysis of 97 empirical studies indicated a positive overall effect of adventure education programs on outcomes such as self-concept, leadership, and communication skills. This study also indicated that there appeared to be ongoing positive effects. The largest empirical study of the effects of outdoor education programs (mostly Outward Bound programs) found small-moderate short-term positive impacts on a diverse range of generic life skills, with the strongest outcomes for longer, expedition-based programs with motivated young adults, and partial long-term retention of these gains.