The adjusted treatment differences between ropinirole and placebo were: sleep disturbance (-15.2, 95% CI -19.37, -10.94; p < 0.0001), sleep quantity (0.7 hours, 95% CI 0.49, 0.94); p < 0.0001), sleep adequacy (18.6, 95% CI 13.77, 23.45; p < 0.0001) and daytime somnolence (-7.5, 95% CI -10.86, -4.23; p < 0.0001).