Mean Brief Pain Inventory (BPI) interference scores at baseline, end of immediate-release (IR) phase, and end of sustained-release (SR) phase. Values at baseline represent means; values at other time points represent least-squares means. At baseline: hydromorphone, n = 99; morphine, n = 101. In IR phase: IR hydromorphone, n = 99; IR morphine, n = 101. In SR phase: OROS® hydromorphone, n = 77; controlled-release (CR) morphine, n = 86.
Hanna et al. BMC Palliative Care 2008 7:17 doi:10.1186/1472-684X-7-17