Determining the credibility of minimal important differences (MIDs) for application in meta-analysis of patient-reported outcomes in systematic reviews and guidelines

Tags: Workshop
Patrick D1, Devji T2, Guyatt G, Carasco Labra A2
1University of Washington, 2McMaster University

Background: investigators increasingly rely on patient-reported outcomes (PRO) as key end points in clinical trials, meta-analyses, and clinical practice guidelines. The interpretation of the magnitude of treatment effects on PRO measures (PROMs), however, presents challenges. The most common reference point for the interpretation of PROMs is the minimal important difference (MID), which provides a measure of the smallest change in a PROM that patients experience as important. Understanding how to evaluate the credibility of MIDs and apply these estimates to enhance interpretability of results from PROMs will ensure the presentation of such data in systematic reviews and guidelines is trustworthy and optimally interpretable.


1) Review the use of MIDs in enhancing interpretability of PROMs in systematic reviews

2) Introduce an instrument for evaluating the credibility of MIDs and apply it to a sample of studies

3) Present a resource for identifying anchor-based MIDs for PROMs: the MID inventory

4) Help participants apply presentation approaches relying on the MID to make PROMs more interpretable in systematic reviews

Description: this workshop will build on another workshop presented earlier in the Colloquium describing approaches to make PROMs more interpretable in systematic reviews, including those relying on MIDs. We will review the concept of the MID and its application to enhance interpretability of PROMs measuring the effect of interventions in systematic reviews. We will then describe an instrument for evaluating the credibility of anchor-based MIDs for PROMs. Participants will apply the credibility instrument to empirical studies estimating the MID for a particular PROM. We will also present an online web platform where participants can search for MID estimates for PROMs. Finally, participants will apply the methods for using the MID to enhance interpretability to a dataset to generate pooled PROM results in MID units, relative effects, and risk differences. We will discuss the relative merits and limitations of each alternative and offer practical guidance on how to present PROM results from meta-analysis in a systematic review or guideline.