Objective: To investigate the generalizability of the results of a randomized controlled trial on the effectiveness of long-term, high-intensity exercises in the rheumatoid arthritis patients in training (RAPIT) trial by comparing the characteristics of the participants with the nonparticipants.
Methods: Participants and nonparticipants were mailed questionnaires on sociodemographic characteristics, health status, reasons not to participate, and attitudes toward intensive exercise.
Results: The questionnaires from 892 (75%) nonparticipants and 299 (97%) participants were collected. The nonparticipants were slightly older, more often male, and had longer disease duration than the participants. The nonparticipants perceived their disease as more serious, used fewer disease-modifying antirheumatic drugs, had a lower level of education, and a more negative attitude toward intensive exercise.
Conclusion: The results of the RAPIT trial might not be generalizable to the entire target population. To promote participation in long-term, high-intensity exercises, health professionals should more actively discuss the potential benefits of exercise with their RA patients while taking into consideration specific factors related to participation.