OBJECTIVE To perform a psychometric evaluation of the GI Symptom Tracker at 10 CF centers across the US.
METHODS: Patients with CF were screened to determine eligibility and completed the GI Symptom Tracker, Cystic Fibrosis Questionnaire-Revised (CFQ-R), enzyme replacement questions and a global status question at a routine clinic visit, administered using an iPad in the CF center. A subset of patients completed a second clinic visit to obtain test-retest data. The psychometric evaluation included confirmation of the scale structure, reliability (internal consistency and test-retest), construct validity, and known groups validity.
RESULTS: More than 175 patients (mix of adults and adolescents) with CF at 10 centers participated. A subset of those patients completed the GI Symptom Tracker, global status question and enzyme replacement questions a second time 10-14 days later to evaluate test-retest reliability. Participants were able to complete the survey easily, with minimal missing data for the tracker.
CONCLUSIONS: The GI Symptom Tracker is easy for patients to complete and demonstrates good content validity based on CF patient-reported experiences of their GI symptoms. This tool will enable clinicians to unobtrusively measure patient-reported GI and nutritional problems and facilitates collaborative patient-provider discussions and decision-making.
