Validation of the standardized version of the Rhinoconjunctivitis Quality of Life Questionnaire

Background: In the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) , the 3 activity questions are selected by the patients themselves. For gre ater efficiency, a version with standardized activities is required. Objective: Our purpose was to develop and validate a standardized version o f the RQLQ, the RQLQ(S), Methods: With use of 5 RQLQ databases, we identified the activities most fr equently selected by patients and formulated 3 generic questions that would encompass the majority of these activities. The RQLQ(S) was tested in a 5- week observational study in 100 adults with symptomatic rhinoconjunctivitis . Patients completed the RQLQ(S), the RQLQ, and other measures of health st atus at baseline and 1 and 5 weeks. Results: The activity domain of the RQLQ(S) consistently gave lower scores than did the activity domain of the RQLQ (P < .001). However, this made ver y little difference to the overall scores (RQLQ[S] = 2.36 +/- 1.23, RQLQ= 2 .43 +/- 1.23), and overall concordance was high (intraclass correlation coe fficient = 0.996). In patients whose rhinoconjunctivitis was stable between clinic visits, reliability (reproducibility and ability to discriminate be tween patients of different impairment) was high for both instruments and a lmost identical (intraclass correlation coefficient = 0.97). Responsiveness to change was also very similar and good (P < .001). Construct validity (c orrelation with other index values of health status) was strong for both th e RQLQ(S) and the RQLQ. Conclusions: The RQLQ(S) has strong measurement properties and measures the same construct as the original RQLQ, The choice of questionnaire should de pend on the task at hand.