Table 2. Minimum Clinically Significant Difference (MCSD) in Four Consecutive 30- Minute Intervals.
| Arithmetic MCSD within Interval | Proportional MCSD within Interval | ||||
|---|---|---|---|---|---|
| n | Mean | (95% CI) | Mean % | (95% CI) | |
| Baseline-30 | 67 | 2.1 | (1.7-2.4) | 27 | (23-32) |
| 30-60 min | 68 | 1.4 | (1.0-1.7) | 19 | (13-24) |
| 60-90 min | 75 | 1.3 | (1.0-1.5) | 22 | (18-27) |
| 90-120 min | 67 | 0.8 | (0.6-1.0) | 13 | (9-18) |
Arithmetic MCSD = (NRSt – NRSt+30)/NRSt associated with descriptors of “a little less pain” or “a little more pain” in each time period
Proportional MCSD = NRSt – NRSt+30 associated with descriptors of “a little less pain” or “a little more pain” in each time period divided by NRS at beginning of each time period