Background: The 28-item Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) has strong measurement properties but for large clinical trials, surveys and practice monitoring, where high efficiency is important, a shorter questionnaire is needed.
Objective: To develop and validate an abbreviated version of the RQLQ.
Methods: Using five RQLQ databases, items with high item-item correlations were combined and then the highest scoring items were selected for the MiniRQLQ (14 questions). There are five domains: activity limitations (standardized), practical problems and nose symptoms, eye symptoms and other symptoms. The MiniRQLQ, which is self-administered, was tested in a 5-week observational study in 100 adults with symptomatic rhinoconjunctivitis. Patients completed the MiniRQLQ, the RQLQ, and other measures of health status at baseline, 1 and 5 weeks.
Results: In patients whose rhinoconjunctivitis was stable between clinic visits, reliability (reproducibility and ability to discriminate between patients of different impairment) was very acceptable for the MiniRQLQ (ICC = 0.93) but not quite as good as for the RQLQ (ICC = 0.97). Responsiveness to change in clinical status was better with the MiniRQLQ than the RQLQ (P = 0. 044). Construct validity (correlation with other indices of health status) was strong for both the MiniRQLQ and the RQLQ. Concordance between the two instruments was high (ICC = 0.87).
Conclusions: The MiniRQLQ has strong measurement properties and measures the same construct as the original RQLQ. The choice of questionnaire should depend on the task at hand.