Reliability and Validity of the Swedish Version of the Hull Airway Reflux Questionnaire (HARQ-S)

INTRODUCTION: Cough is a common symptom for which patients seek medical care and is defined as chronic if it has lasted for more than 8 weeks. The Hull Airway Reflux Questionnaire (HARQ) was developed with the aim of eliciting the major component of chronic cough. It comprises 14 items with a maximum total score of 70. A Swedish version (HARQ-S) has previously been developed but not yet formally validated. The aim of the present study was to validate the HARQ-S in terms of instrumental reliability and concurrent validity. METHODS: A total of 67 consecutively selected non-smoking patients with chronic cough and 91 non-smoking allegedly healthy controls were asked to answer two questionnaires, the HARQ-S and a local questionnaire, at two occasions about 3 weeks apart. RESULTS: The HARQ-S showed good psychometric properties. The patients had significantly higher total scores (p < 0.001) compared to the controls, and the questionnaire showed outstanding discrimination ability to distinguish between patients and controls, with an area under the receiver operating characteristic curve of 0.99. Fifty patients and 77 controls completed the HARQ-S twice, showing good test–retest agreement in all items as well as in the total scores in both groups, and without any significant differences over time. CONCLUSION: The Swedish version of the HARQ is a valid and reliable questionnaire with good agreement between the two measurements in both patients and controls. The HARQ-S has good reliability and validity and can be used as a diagnostic tool in Swedish-speaking patients with chronic cough.