To estimate the minimum clinically important difference (MCID) of the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) and the International Consultation on Incontinence Questionnaire-Lower Urinary Tract Symptoms Quality of Life (ICIQ-LUTSqol) using both anchor-based and distribution-based methods for women with stress urinary incontinence undergoing non-surgical treatment.
Data from a randomised clinical trial evaluating efficacy of a non-surgical intervention in women with stress urinary incontinence were used for analyses. The overall score of ICIQ-UI SF ranges from 0 to 21, with greater values indicating increased severity. The ICIQ-LUTSqol ranges from 19 to 76, with greater values indicating increased impact on quality of life. Instruments used in the anchor-based method were the Patient Global Impression of Improvement, patient satisfaction, one-hour pad test and the incontinence episode frequency. The distribution-based method used an effect size of 0.5 standard deviation. Triangulation of findings was used to converge on a single value of MCID.
At 12-months post-treatment, 106 (88.3%) participants completed the follow-up and were included in the analysis. Anchor-based MCIDs of the ICIQ-UI SF were between 3.4 and 4.4, while the distribution-based MCID was 1.7. Anchor-based MCIDs of the ICIQ-LUTSqol were between 4.8 and 6.9, while the distribution-based MCID was 5.2. Triangulation of findings showed that MCIDs of 4 for ICIQ-UI SF and 6 for ICIQ-LUTSqol were the most appropriate.
For women undergoing non-surgical treatments for incontinence, reductions of 4 and 6 points in ICIQ-UI SF and ICIQ-LUTSqol respectively are perceived as clinically meaningful.
Urology. 2019 Aug 12 [Epub ahead of print]
Renly Lim, Men Long Liong, Ka Keat Lim, Wing Seng Leong, Kah Hay Yuen
School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia; Quality Use of Medicines and Pharmacy Research Centre, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia. Electronic address: ., Department of Urology, Island Hospital, Penang, Malaysia., Programme in Health Services and Systems Research, Duke University-National University of Singapore (Duke-NUS) Medical School, Singapore., Department of Urology, Lam Wah Ee Hospital, Penang, Malaysia., School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia.