This is a dissemination study whose objective is to explore the effectiveness, acceptability, and scalability of the Shamiri intervention when implemented in a large-scale naturalistic dissemination study in Kenyan secondary schools. Specifically, this study has two broad goals: 1) to test the effectiveness of Shamiri on mental health and psychosocial outcomes when delivered naturalistically on a large scale through either a centralized and de-centralized (train the trainers) administration, and 2) to examine and measure outcomes of these large-scale dissemination models.~For goal 1, participants will receive Shamiri directly through the Shamiri team or through an implementation partner. The investigators will measure mental health and psychosocial outcomes to determine if these outcomes compare to those reported in prior RCTs of Shamiri. The investigators hypothesize that participants receiving Shamiri will experience similar improvements in mental health and psychosocial outcomes as reported in previous RCTs. The investigators don't have a priori hypothesis on whether the mode through which the participants receive the intervention will affect intervention outcomes.~To achieve goal 2, investigators measure the following implementation related outcomes: intervention fidelity, cost, sustainment, acceptability, penetration, and cost-effectiveness. The investigators hypothesize that the Shamiri intervention will achieve high ratings in all intervention outcomes.
The present research study will involve investigating the efficacy of large-scale dissemination models of evidence-based character strength interventions in secondary schools in Kenya. This intervention, derived from a previously tested intervention named Shamiri, or thrive in Kiswahili, uses positive psychology and accessible life skills to build individual resilience and wellness. This will be a one-arm trial with participants recruited from 20 secondary schools in Nairobi, Kiambu and Makueni counties. The investigators estimate a sample size of 3000 youth, working on an intention to treat basis. All interested participants will be admitted to the program, with no exclusion criteria applied. The investigators will report on the efficacy of character strength interventions on wellbeing and mental health outcomes. Further, the investigators will also assess the scalability and acceptability of the program post intervention. Additionally, the investigators will examine moderator effects on the participants, baseline attributes of the participants, and potentially the effects of candidate mediators on intervention effects.