Four RCTs (n=1,088) were included in this review. All trials scored 3 or higher on the Jadad scale.
There was a small but significant reduction in annual rate of joint space width decline of 0.07mm/year (95% CI 0.03 to 0.10; four RCTs) in patients treated with oral chondroitin sulphate compared to placebo treated patients (SMD 0.26, 95% CI 0.14 to 0.38). Heterogeneity was not statistically significant.
Sensitivity analyses that assessed influence of excluding unpublished studies (0.07mm/year, 95% CI 0.01 to 0.12; three RCTs) and studies of different durations (0.13mm/year, 95% CI 0.06 to 0.20; two RCTs) showed no substantial changes in the pooled estimate. Heterogeneity was not statistically significant.