Applying area-under-the-curve analysis to enhance interpretation of response profiles: an application to sleep quality scores in patients with fibromyalgia.

PURPOSE

To introduce an application of area-under-the-curve (AUC) that can enrich interpretation of response analysis and illustrate this method on sleep quality scores in patients with fibromyalgia.

METHODS

Data were from a 14-week, randomized trial conducted in 750 patients with fibromyalgia treated with placebo or pregabalin (300, 450, or 600 mg/day); sleep quality was assessed daily by the patient using an 11-point numeric rating scale.

RESULTS

Response profiles were implemented for responders who improved (or stayed the same) numerically in sleep quality scores from baseline to week 14 and, separately, for non-responders who worsened (numerically less favorable scores at week 14). Differences between pregabalin and placebo were assessed using an AUC analysis. Improvement in sleep quality was significantly better with pregabalin and can be interpreted as if pregabalin responders improved by 10.8% (300 mg), 14.7% (450 mg), and 19.0% (600 mg) above the placebo responders. Conversely, decrement in sleep quality was worse with placebo and can be interpreted as if placebo non-responders worsened by 3.6% (300 mg), 2.9% (450 mg), and 3.9% (600 mg) over pregabalin non-responders.

CONCLUSIONS

The application of an AUC analysis to response profiles for responders and non-responders can enrich the interpretation of sleep quality scores in patients with fibromyalgia. The method can be applied more generally to facilitate and enhance the interpretation of treatment differences on outcomes.