Using GI-specific patient outcome measures in renal transplant patients: Validation of the GSRS and GIQLI

Abstract

<h4>Introduction</h4>Gastrointestinal (GI) side-effects occur frequently as a result of immunosuppressant regimens used in renal transplant patients. Little effort has been made to quantify the impact of these side-effects on patients' health-related quality of life and symptom severity.<h4>Objective</h4>To assess the psychometric characteristics of two GI-specific outcome instruments (the Gastrointestinal Rating Scale (GSRS) and the Gastrointestinal Quality of Life Index (GIQLI)) for use in post-renal transplant patients.<h4>Methods</h4>Cross-sectional study conducted at 5 clinical centers in 4 countries. Patients were required to be on mycophenolate mofetil and a calcineurin inhibitor. Patients completed the GSRS, GIQLI and two generic instruments (the Psychological General Well-Being Index and the EQ-5D) at one timepoint. Reliability, construct and known groups validity were assessed.<h4>Results</h4>In general the GSRS and the GIQLI demonstrated Cronbach's alphas higher than 0.70. The GIQLI was moderately to highly correlated with the PGWB and EQ-5D. Correlations among the GSRS and generic instruments were slightly lower. The GSRS and GIQLI both distinguished between patients with and without GI complaints (all p<0.05).<h4>Conclusions</h4>The GSRS and the GIQLI are appropriate for use in a post-renal transplant population. Scores on both instruments demonstrated significant differences between renal transplant patients with GI complications and without GI complications.