Ik. Wiklund et al., Quality of life in reflux and dyspepsia patients. Psychometric documentation of a new disease-specific questionnaire (QOLRAD), EURO J SURG, 164, 1998, pp. 41-49
Objective. To develop a disease-specific QOL instrument (QOLRAD) addressing
patient concerns in gastroesophageal reflux disease (GERD) and dyspepsia.
Patients. 759 male (45%) and female (55%) patients with a mean age of 48.4
years (sd 15.2) were used in the psychometric evaluation.
Main outcome measures. A pilot version of QOLRAD, the Gastrointestinal Symp
toms Rating Scale (GSRS) and the SF-36 were completed prior to endoscopy. I
tems with a high ceiling effect, items measuring a different construct, i.e
. with a low squared multiple correlation (R < 0.5) with the other items, i
tems that showed redundancy by a high correlation (>0.80) with another item
were removed. A confirmatory factor analysis was also performed.
Results. The final questionnaire included 25 items depicting problems with
emotions, vitality, sleep, eating/drinking, and physical/social functioning
. The internal consistency reliability was high (alpha value overall 0.97,
dimensions 0.89-94). Construct validity, i.e. the associations between simi
lar constructs in the QOLRAD, the SF-36 and the GSRS scores was confirmed.
Pain and symptom severity were markers of impaired QOL. The impact on healt
h-related QOL was similar across the functional gastrointestinal disorders
with the exception of patients with a normal endoscopy, who did slightly wo
rse.
Conclusion. The QOLRAD is a shea and user-friendly instrument with excellen
t psychometric properties. Its responsiveness to change in (AVMCl)clinical
trials is currently being explored.