Introduction: Pain diaries are important tools for clinical trials and optimal assay sensitivity of outcomes derived from these diaries is a worthwhile goal. Jensen and colleagues recently reported results suggesting that single-day diary-based outcomes could possibly be as psychometrically sound as outcomes based on taking the average of many diaries.
Materials and Methods: In this paper, we attempted to replicate those results with several diary data sets.
Results and Discussion: We come to a different conclusion than that advanced by Jensen and colleagues and conclude that their results were unusual in that very high test-retest reliability among days was found. With our 4 diary data sets we find that aggregating multiple diaries yields more reliable outcomes and improved sensitivity. We suggest that using single-day diaries will often lead to underpowered studies and that pretesting is advised before adopting single-day diaries. We also suggest that other researchers replicate these findings within their diary-based clinical trials.
*Department of Psychiatry and Behavioral Science, Stony Brook University, Stony Brook, NY
†ERT Inc., Pittsburgh, PA
Supported by grants from the National Institutes of Health (AR054626 [J.E.B., PI]), 1 U01-AR052170 (A.A.S., PI), 1 U01-AR057948 (A.A.S. and J.E.B., MPIs) and the Stony Brook University GCRC (Grant M01-RR10710) from the National Center for Research Resources. A.A.S. is a senior scientist with Gallup and a senior consultant with ERT. The remaining authors declare no conflict of interest.
Reprints: Arthur A. Stone, PhD, Department of Psychiatry and Behavioral Science, Stony Brook University, Stony Brook, NY 11974-8790 (e-mail: email@example.com).
Received August 19, 2013
Received in revised form December 2, 2013
Accepted September 4, 2013