Determining the minimally clinically important difference for the pediatric liver transplant quality of life questionnaire.

Purpose: The Pediatric Liver Transplant Quality of Life (PeLTQL) questionnaire is a disease-specific patient reported outcome measure for pediatric liver transplant (LT) recipients. To-date, threshold values above which a change in PeLTQL score is considered meaningful to patients are unavailable. This study proposes the first values for the minimally clinically important difference (MCID) for the PeLTQL.

Methods: In this retrospective cohort study, anchor and distribution-based methods were used to estimate the MCID for the PeLTQL. Questionnaires completed between March 2013, and July 2022 were included if data from two sequential visits were available. An internal anchor question was used for anchor-based determination of the MCID. A final MCID estimate was ascertained from triangulation of all methods.

Results: PeLTQL data from 65 LT recipients (26 [40%] male, 17 [42%] biliary atresia, median age at LT 3.08 years [interquartile range 0.99-7.30]), and their caregivers were included for analysis. Median patient age at time of baseline PeLTQL completion was 13.84 (10.90-15.86) years. The MCID for self-PeLTQL total scores ranged from 4.53 to 8.46, and from 4.47 to 8.85 for proxy responses. By triangulation, the MCID of the PeLTQL total score was 6.45 and 6.78 for self and proxy responses respectively.

Conclusion: A change in PeLTQL score of 6.5 or more points suggests a change in health status that is meaningful to the patient, providing the clinical team an opportunity to engage the patient's voice in reassessing current health status and management strategies.