Responsiveness and interpretation of a symptom severity index specific to upper gastrointestinal disorders.
OBJECTIVE
Determining clinically meaningful change of patient-reported outcome measures is important for evaluating effectiveness of treatments for gastrointestinal (GI) diseases. This study evaluates responsiveness of the Patient Assessment of Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM) in gastroesophageal reflux disease (GERD) and dyspepsia.


METHODS
The PAGI-SYM was based on a review of the published literature and interviews with patients and clinicians. Items were developed to be linguistically and culturally appropriate for multicountry studies. The PAGI-SYM includes 6 subscales: heartburn/regurgitation, fullness/early satiety, nausea/vomiting, bloating, upper abdominal pain, and lower abdominal pain. Subjects with GERD (n = 810) or dyspepsia (n = 767) participated in this multicountry, observational study. All subjects completed the PAGI-SYM, a global symptom relief questionnaire, and a measure of patient-rated change in GI-related symptoms, the Overall Treatment Effect (OTE) scale. Responsiveness was evaluated at 8 weeks by comparing groups by disease, symptom relief, and OTE (improved, stable, and worsened).


RESULTS
Subjects reporting symptom relief reported significantly lower (better) PAGI-SYM scores than those reporting no symptom relief ( P < 0.0001 to P < 0.0005). Subjects with improvements in overall GI symptoms exhibited significant decreases in PAGI-SYM subscale scores compared with those who remained the same or worsened (all P values < 0.0001). Effect sizes ranged from 0.21-1.28, and standard errors of measurement ranged from 0.29-0.63, depending on subscale and disease sample.


CONCLUSIONS
The PAGI-SYM is a brief symptom severity instrument that measures common GI symptoms. Results suggest that the PAGI-SYM is responsive and sensitive to change in clinical status in subjects with GERD or dyspepsia.
Revicki
Dennis A
DA
Center for Health Outcome Research, MEDTAP International, Bethesda, MD 20814, USA. Revicki@medtap.com
Rentz
Anne M
AM
Tack
Jan
J
Stanghellini
Vincenzo
V
Talley
Nicholas J
NJ
Kahrilas
Peter
P
De La Loge
Christine
C
Trudeau
Elyse
E
Dubois
Dominique
D
D000328:Adult; D004358:Drug Therapy; D004415:Dyspepsia / Q000145:classification* / Q000188:drug therapy / Q000523:psychology; D005260:Female; D005764:Gastroesophageal Reflux / Q000145:classification* / Q000188:drug therapy / Q000523:psychology; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D016896:Treatment Outcome