Development and Validity Assessment of a Self-evaluation Questionnaire for Functional Dyspepsia: A Multicenter Prospective Study in Korea

BACKGROUND/AIMS: Patient-reported outcomes (PROs) are essential for clinical decision making, conduction of clinical research, and drug application acquisition in functional gastrointestinal disorders. The aim of this study is to develop a PRO instrument and to determine the respondents’ perception of the efficacy of therapeutic agents for functional dyspepsia (FD). METHODS: A self-evaluation questionnaire for dyspepsia (SEQ-DYSPEPSIA) was developed and validated through a structured process. The 2-week reproducibility was evaluated, and the construct validity was assessed by correlating the scores of SEQ-DYSPEPSIA (including typical and major FD symptom subscales). Finally, the response to medication was assessed by comparing the changes after 4 weeks of treatment. RESULTS: A total of 193 Korean patients (age 48.5 ± 13.6 years, 69.4% women) completed the questionnaire. SEQ-DYSPEPSIA with 11 items had a good internal consistency (alpha = 0.770-0.905) and an acceptable test-retest reliability (intraclass correlation coefficient = 0.733-0.859). The self-evaluation questionnaire (SEQ)-major FD score highly correlated with the postprandial fullness/early satiety domain of the Patient Assessment of Gastrointestinal Symptom Severity Index (correlation coefficient r = 0.741, P < 0.001), Nepean Dyspepsia Index-Korean version (NDI-K) (r = 0.839, P < 0.001), and NDI-K quality of life (r = −0.275 to −0.344, P < 0.001). After medical treatment, decrease in the SEQ-typical FD and SEQ-major FD was significantly greater in the responder group than in non-responder group (P = 0.019 and P = 0.009, respectively). CONCLUSION: This study suggests that the Korean version of SEQ-DYSPEPSIA has good reliability and validity, and can be a useful PRO measurement tool in patients with FD.