Development of a valid and reliable food retention questionnaire

Objectives Food retention (FR) is a pathological process which manifests as epigastric or abdominal fullness or pain, dyspepsia, water brash, sickness, languidness, edema, weight gain, or joint pain. The present study was conducted to examine the reliability and validity of a food retention questionnaire (FRQ) and to define its optimum cut-off score. Methods A total of 194 outpatients (62 men, 132 women) were asked to complete the FRQ. Thirteen clinicians determined whether or not the 194 outpatients exhibited FR. We estimated the internal consistency and construct validity for the FRQ. The total scores from the FRQ and clinicians’ diagnoses of the patients were used to perform receiver operating characteristics (ROC) curve analyses and to define an optimum cut-off score for the FRQ. Results The FRQ exhibited a satisfactory internal consistency ( α = 0.852). In the test of construct validity using principal component analysis, a total of four factors (gastrointestinal distress, Dampness, food hypersensitivity, and stool–urine–pain) were extracted (total percentage of variance = 53.2%). ROC curve analyses showed that the FRQ had a moderate discriminative ability for FR (sensitivity = 70.7%, specificity = 76.8%, and AUC = 0.788). The optimum cut-off score was defined as six points. Conclusions Our results suggest that the FRQ is a valid and reliable instrument for evaluating FR.