Methods to determine the minimum important difference for a sexual event diary used by postmenopausal women with hypoactive sexual desire disorder.

INTRODUCTION Recently, there has been much discussion in the literature about how to determine the meaningfulness of results generated from a patient-reported outcome measure. A number of reviews have shown that there are two main approaches: anchor- and distribution-based approaches for determining the minimum important difference (MID) for a new measure. There are issues with calculating an MID using each method: Will the two approaches give the same estimate? If the estimates differ, how do you decide on one estimate? Would asking patients directly be more beneficial? AIM A case study was presented to address these issues based on a newly developed diary assessing number of satisfactory sexual events (SSEs) per week in women with hypoactive sexual desire disorder (HSDD). METHODS Anchor- and distribution-based estimates were generated from data gathered in two double-blind, placebo-controlled, parallel group trials for the treatment of HSDD (N = 788). A novel interview study was used to ask women directly about an MID for SSEs (N = 77). MAIN OUTCOME MEASURES Defining the MID for an SSE diary in women with HSDD. RESULTS The estimates varied, producing a range of mean MID estimates between 0.04 and 0.46 SSEs per week. CONCLUSION We recommend that rather than defining the MID, a range should be selected from the set of estimates formed by the limits of the 95% confidence intervals.