Patient-based assessment in dyspepsia - Development and validation of Dyspepsia Symptom Severity Index (DSSI)

This paper describes the development and testing of a new self-report measu re. the Dyspepsia Symptom Severity Index (DSSI), for assessing the severity of symptoms commonly associated with dyspepsia. The instrument was based o n the literature, focus groups, and feedback from gastroenterologists; 48 p atients and 24 controls participated in testing. Patients completed the DSS I and a symptom diary to test concurrent validity; one-week reproducibility was evaluated in 21 stable patients. Three subscales comprise the 20-item DSSI, representing reflux-, ulcer-, and dysmotility-like symptoms. Subscale internal consistency levels (alpha) were high (0.84-0.89), total score alp ha levels were very good (0.76, 0.80), and scores were reproducible (ICC = 0.90-0.92). Correlations between the DSSI and diary were moderate to strong (r = 0.33-0.77; P < 0.05). Patients reported significantly more severe sym ptoms than controls (P < 0.001). Results indicate the DSSI is a reliable an d valid tool for evaluating symptom severity in patients with functional dy spepsia.