Objective: Adherence to behavioural intervention programmes is a necessary condition for beneficial outcomes to be achieved. This study tested whether social cognitive variables and coping plans predict adherence.
Design and methods: Adherence was examined in a randomized controlled trial with healthy older women (age range: 70-93 years), who were randomized to a physical (N= 86) or a mental (N= 85) activity intervention. Intentions, self-efficacies, coping plans, and objectively measured adherence levels were assessed. A moderated mediation analysis evaluated the power of coping plans to translate intention into behaviour, depending on levels of prior adherence.
Results: Adherence to the physical activity programme (65%) was significantly lower than adherence to the mental activity programme (84%, p < .001). Intentions (β= .22) weakly predicted adherence in the initiation period of the physical activity programme (6 weeks); pre-action self-efficacy predicted adherence in the initiation period of the mental activity programme (β= .35). In both groups, coping plans predicted mid-period adherence (10 weeks) and long-term adherence (20 weeks), moderated by prior adherence (all ps < .01). Coping plans mediated the relationship between intentions and behaviour only in the exercise condition.
Conclusions: Instructing older individuals to generate coping plans facilitated their adherence to physical and mental activity programmes. This effect was larger for participants with lower levels of prior adherence--and may have prevented them from dropping out of the programme.
©2011 The British Psychological Society.