We evaluated the existing evidence on the effect of exercise therapy in patients with hip osteoarthritis (OA) compared to no treatment and explore whether a further trial will change the current evidence.

Systematic review and cumulative meta-analysis using randomized controlled trials (RCT) to determine the effect on pain and function post-treatment, and at 6–9 months after treatment.

Standardized mean difference (SMD) ​≤ ​−0.37 was considered clinically worthwhile. Extended funnel plots were used to simulate the impact of a new trial on the pooled effect size of pain and function.