Further validation of the IBS-QOL: a disease-specific quality-of-life questionnaire.
OBJECTIVE
There has been growing interest in the investigation of health-related quality of life (HRQOL) among patients with gastrointestinal (GI) disorders. We recently reported on the development and preliminary validation of the IBS-QOL, a specific quality-of-life measure for irritable bowel syndrome (IBS). The aim of this study was to determine the longitudinal construct validity (responsiveness) of the IBS-QOL.


METHODS
Female patients enrolled in a multicenter treatment trial for functional bowel disorders were studied pre- and posttreatment with the IBS-QOL and other health status measures. Based on the response to treatment for several variables (pain/14-day score, daily function, and days in bed/3 months), patients were stratified into Responders, Partial Responders, and Nonresponders. Change scores in the IBS-QOL were then statistically compared with changes in the other variables to determine their correlation and whether Responders were significantly different from non- and Partial Responders on the IBS-QOL.


RESULTS
There was a significant correlation between change scores on the IBS-QOL and the other measures of treatment effect (Pain/14 days, r = 0.25, p < 0.002; Sickness Impact Profile [SIP] Total Score, r = 0.28, p < 0.0004). In addition, the IBS-QOL scores significantly differentiated Responders from Nonresponders for most of the variables tested (regression trend test for Pain/14 days, p < 0.04; SIP Total, p < 0.0001; SIP Physical, p < 0.0001; SIP Psychosocial, p < 0.002, and SIP Eating, p < 0.04).


CONCLUSIONS
The IBS-QOL is responsive to treatment in a referral-based clinical population of patients with functional bowel disorders.
Drossman
D A
DA
UNC Center for Functional GI and Motility Disorders, Division of Digestive Diseases, University of North Carolina, Chapel Hill 27599-7080, USA.
Patrick
D L
DL
Whitehead
W E
WE
Toner
B B
BB
Diamant
N E
NE
Hu
Y
Y
Jia
H
H
Bangdiwala
S I
SI
D000328:Adult; D000929:Antidepressive Agents, Tricyclic / Q000008:administration & dosage; D015928:Cognitive Behavioral Therapy; D003109:Colonic Diseases, Functional / Q000175:diagnosis / Q000523:psychology* / Q000628:therapy; D003891:Desipramine / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008875:Middle Aged; D010147:Pain Measurement; D010353:Patient Education as Topic; D011788:Quality of Life; D012803:Sick Role; D018434:Sickness Impact Profile; D016896:Treatment Outcome
D000929:Antidepressive Agents, Tricyclic; D003891:Desipramine