Seventeen RCTs, reported in 18 publications, were included in the review. It is unclear whether all the study details are shown in the review's data extraction table. It was not possible to calculate the total number of participants in these studies.
It was not possible to obtain evidence on the content of exercise interventions, as studies were hampered by lack of attention to proper concealment, reporting of adverse effects, and long-term effects of exercise treatment. The lack of standard outcome measures was also noted. The results from trials comparing effects of different exercise treatment programmes were inconclusive.
Pain (14 trials): a small to moderate beneficial effect of exercise treatment was found for pain in knee osteoarthritis. This effect was found in participants with mild or moderate osteoarthritis, recruited from both community and clinic, who were being treated with various types of exercise treatment for at least 8 weeks.
Self-reported disability (6 trials): there was evidence for a small beneficial effect of exercise on self-reported disability. This effect was found in participants with mild or moderate osteoarthritis, recruited from both the community and the clinic, who were being treated with various types of exercise.
Walking (8 trials): the evidence indicated a small beneficial effect of exercise treatment on walking performance, and one trial showed a significant effect on both self-selected speed of walking and stepping, both clinically-relevant functional outcomes as recommended by OMERACT (see Other Publications of Related Interest).
Patient global assessment of effect (2 trials): evidence indicated that there is a need for future studies to integrate the beneficial effects of exercise according to the patients' global assessment.