The effect of nurse-led motivational interviewing based on the trans-theoretical model on promoting physical activity in healthy older adults: A randomized controlled trial

Aim: The aim of this study was to evaluate the effect of motivational interviewing based on the trans-theoretical model promoting physical activity in older adults. Methods: A randomized controlled trial study was conducted with 117 older adults (intervention group: 58, and control group: 59) between April and November 2019. The data were collected via a questionnaire, trans-theoretical model scales, the Physical Activity Scale for the Elderly, the Katz Activities of Daily Living scale and a pedometer. The 24-week intervention consisted of regular motivational interviewing. The control group received usual care at the family health centre. Results: Following the intervention, the Intervention Group showed significant improvements Exercise Processes of Change Scale, Exercise Self-Efficacy Scale and Perceived Benefits of the Decisional Balance Scale for Exercise. There was a significant difference between the groups in terms of stages of change. In the Intervention Group, 81.5% were in the contemplation stage in the pre-test, while in the post-test, 70.4% had transitioned to the action stage. In contrast, in the control group, 62.5% were in the contemplation stage initially, but in the post-test, only 9.3% had reached the action stage. The mean number of step counts increased significantly in favour of the Intervention Group, as did the Physical Activity Scale for the Elderly total score. Conclusion: The trial indicated that after the trans-theoretical model-based motivational interviewing, the stages of change among the older adults improved, as did their exercise behaviours. It is recommended that the trans-theoretical model and motivational interviewing be used by nurses to improve healthy lifestyle stage behaviours in older adults.