Minimally important differences for Patient Reported Outcomes Measurement Information System pain interference for individuals with back pain
Authors Amtmann D, Kim J, Chung H, Askew R, Park R, Cook K
Received 27 August 2015
Accepted for publication 19 January 2016
Published 27 April 2016 Volume 2016:9 Pages 251—255
Checked for plagiarism Yes
Review by Single-blind
Peer reviewers approved by Dr Kerui Gong
Peer reviewer comments 3
Editor who approved publication: Dr Michael Schatman
Dagmar Amtmann,1 Jiseon Kim,1 Hyewon Chung,2 Robert L Askew,3 Ryoungsun Park,4 Karon F Cook5
1Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA; 2Department of Education, Chungnam National University, Daejeon, Republic of Korea; 3Department of Psychology, Stetson University, Deland, FL, USA; 4Theoretical and Behavioral Foundations Division, Wayne State University, Detroit, MI, USA; 5Department of Medical Social Science, Northwestern University, Chicago, IL, USA
Background: The minimally important difference (MID) refers to the smallest change that is sufficiently meaningful to carry implications for patients' care. MIDs are necessary to guide the interpretation of scores. This study estimated MID for the Patient Reported Outcomes Measurement Information System (PROMIS) pain interference (PI).
Methods: Study instruments were administered to 414 people who participated in two studies that included treatment with low back pain (LBP; n=218) or depression (n=196). Participants with LBP received epidural steroid injections and participants with depression received antidepressants, psychotherapy, or both. MIDs were estimated for the changes in LBP. MIDs were included only if a priori criteria were met (ie, sample size ≥10, Spearman correlation ≥0.3 between anchor measures and PROMIS-PI scores, and effect size range =0.2–0.8). The interquartile range (IQR) of MID estimates was calculated.
Results: The IQR ranged from 3.5 to 5.5 points. The lower bound estimate of the IQR (3.5) was greater than mean of standard error of measurement (SEM) both at time 1 (SEM =2.3) and at time 2 (SEM =2.5), indicating that the estimate of MID exceeded measurement error.
Conclusion: Based on our results, researchers and clinicians using PROMIS-PI can assume that change of 3.5 to 5.5 points in comparisons of mean PROMIS-PI scores of people with LBP can be considered meaningful.
Keywords: minimally important differences, pain interference, back pain, Patient Reported Outcomes Measurement Information System, responsiveness, PROMIS
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.Download Article [PDF] View Full Text [HTML][Machine readable]