Main results
This study gives a differentiated insight in to the implementation of the planned complex intervention, according to the MRC framework, including reach, dose, fidelity and adaption. With regard to reach, the PACINPAT intervention reached all but three participants in the intervention group. With regard to dose, the subgroup analysis showed that the “early dropout” group had significantly shorter in-person counseling sessions compared with the “low” and “high dose” groups. Additionally, the “high dose” group had significantly longer remote counseling sessions compared with the “low dose” group. With regard to fidelity, during in-person counseling sessions, physical activity plans were made less frequently and the mobile application was introduced less frequently in the “early dropout” group compared with the “low” and “high dose” groups. During remote counseling sessions, BCTs used in over 50% of the sessions were action planning (1.4.), goal setting (behavior) (1.1.), discrepancy between current behavior and goal (1.6.), review of behavior goals (1.5.) and feedback on behavior (2.2.). All but two of the BCTs on the “Anchor List” for physical activity were frequently used (social support [3.1.] and instruction on how to perform behavior [4.1.]). With regard to adaptation, the MoVo intervention was adapted in delivery mode and timing of content. The interval between telephone counseling sessions was adapted to the participants.