Statistical methods
SECONDARY, BLIND
All data were quality-checked after trial completion and locked for any corrections. The intention to treat (ITT) population was analysed blind. All clinical endpoints were first tested for an overall effect of the trial drug groups, and pairwise comparisons between groups were done if statistical significance was achieved with respect to overall group effect. Standard descriptive statistics such as mean, median, range, 95% confidence intervals (95% CI), and 1st and 3rd quartile (Q1, Q3) were used to describe the endpoints where appropriate for a useful comparison with previously published studies. The primary endpoint SPI and the secondary endpoints SPID, duration of analgesia, MAXPID, participants using rescue drug, and number of rescue drug tablets used were analysed with the various models of the 