|INCIDENCE measures, variable- oriented hypotheses|
|Research question||Outcome||Method of analysis||Results from the model data set|
|All respondents, n = 244||Highly compliant respondents, answering 80% (≥15/18 weeks), n = 161|
|3A: Incidence during the full study period for the whole sample and for subgroups||Recovery, i.e. reporting 0 or 1 pain days in 2 consecutive weeks = Event||Time to event analysis, with Kaplan Meier curves. Log rank test for differences between groups||Illustrated in Figure 2. Logrank test for effect of previous duration: p < 0.001||Logrank testfor effect of previous duration: p = 0.002|
|3B: Incidence for the full study period in relation to the selected predictive variables||Recovery, i.e. reporting 0 or 1 pain days in 2 consecutive weeks = Event||Time to event analysis with a) Cox proportional hazard regression or b) Discrete hazard regression||Hazard ratio (HR) showing recovery, long duration reference, estimate and 95% CI: a) 1.95 (95% CI: 1.4-2.6), b) 2.03 (95% CI: 1.5-2.7).||Hazard ratio (HR) showing recovery, long duration reference, estimate and 95% CI: a) 1.95 (95% CI: 1.4-2.6), b) 2.03 (95% CI: 1.5-2.7).|
|3 C: Time point for an event during the pain course||The time point of change in the course of pain = Event||Spline regressions, the event defined as the intersection of linear regression lines (the knot).||Short duration: knot at 4.5 weeks Long duration: knot at 5.9 weeks||Short duration: knot at 4.4 weeks Long duration: knot at 5.8 weeks|
Axén et al.
Axén et al. BMC Medical Research Methodology 2012 12:105 doi:10.1186/1471-2288-12-105