Table 4.

Insights from step 1 of this formative research (focus groups and narrative literature review) that informed selection of 5 determinants of diet and physical activity in the context of type 2 diabetes mellitus (T2DM) prevention featured in the intervention’s program theory.

Determinants	Step 1 insights
Knowledge of ways to help prevent T2DM through diet and physical activity	Focus groups: Providing information on cooking healthy meals featured as 1 of the 2 specific elements of culturally adapted text messages requested by focus group participants. Literature review: Literature review highlighted lack or insufficient knowledge on what constitutes a healthy diet and the right amount and type of physical activity in the context of T2DM preventions as well as insufficient knowledge of link between lifestyle and risk of developing T2DM as associated with diet and physical activity.
Self-efficacy; sense of control over one’s diet and physical activity and sense of inevitability about developing T2DM	Focus groups: “Friendly encouragement” was one of the general characteristics of culturally adapted text messages requested by focus groups participants. The “friendly encouragement” can be interpreted in the context of enhancing person’s belief that they can get through the steps necessary to achieve the desired outcomes and have necessary skills and resources to deal with situations and challenges they face. This in turn corresponds with the concept of self-efficacy and also to an extend sense of control as described in psychology literature. Literature review: Lack of sense of control over one’s diet and level of physical activity was featured as one of the factors associated with diet and physical activity in relation to T2DM prevention. Sense of inevitability about developing T2DM was also featured as an important factor in the context of T2DM prevention.
Planning skills, including goal setting	Focus groups: “Setting achievable goals” featured as 1 of the 2 specific elements of culturally adapted text messages requested by focus group participants. In addition, “friendly encouragement” was featured as 1 of the 3 general attributes of culturally adapted text messages request by focus group participants. These correspond with the concept of self-efficacy or sense of control as it focuses on supporting the individual in developing believe that they can perform the desired actions and behaviors. Literature review: No direct evidence on the role of action planning or goal setting emerged from the literature review.
Norms and beliefs guiding diet and physical activity	Focus groups: Gender and social norms relate to an expectation to prioritize the needs of others such as family members were discussed by focus groups participants. This was in the context of focus groups participants asking for the text messages to their individual needs and priorities (eg, “me first” or “me time”). Literature review: Social and gender norms with regard to such aspects of day-to-day life as preparing meals at home, attending social and family gatherings, and organized exercise have been strongly featured as impacting on diet and physical activity in the context of T2DM prevention in the literature review.
Peer support and companionship	Focus groups: “Companionship” was 1 of the 3 general attributes of culturally adapted text messages request by focus group participants. This meant that the text messages were meant to serve as form of companionship to its users (having someone supporting them in their journey of behavior change), but also more generally supported people in seeking companionship and peer support in the context of diet and physical activity. Literature review: Having a companion for physical activity and exercise and the physical activity providing an opportunity for socializing was identified as an important factor in the context of increasing physical activity in the literature review.