Methods to determine the minimum important difference for a sexual event diary used by postmenopausal women with hypoactive sexual desire disorder
Symonds, Tara; Spino, Cathie; Sisson, Melanie; Soni, Paresh; Martin, Mona; Gunter, Lacey; Patrick, Donald L.
Journal of Sexual Medicine
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.