Psychometric evaluation of a daily gastro-oesophageal reflux disease symptom measure.

OBJECTIVE

The objective of this study was to evaluate the validity of the Heartburn Reflux Dyspepsia Questionnaire (HRDQ), a newly developed measure of gastro-oesophageal reflux disease (GORD) symptoms. Specifically, the HRDQ was developed for patients, who still experience symptoms with proton pump inhibitor (PPI) treatment.

MATERIAL AND

METHODS

The psychometric properties of HRDQ were evaluated based on data from two clinical trials of patients with GORD with a partial response to PPIs, one from the UK and one from Denmark and Germany.

RESULTS

The HRDQ had good internal consistency (Cronbach's alpha range .83-.88) and test-retest reliability (intraclass correlation coefficient range .71-.90). Convergent and discriminant validity were supported by high correlations with ReQuest™ and ability to differentiate between groups based on ReQuest™ cut-off values. Responsiveness of HRDQ was demonstrated by moderate to high correlations with ReQuest™ change scores and time with symptoms. An HRDQ cut-off value of 0.70 for definition of 'bad day' was also evaluated.

CONCLUSIONS

Based on existing evidence, the HRDQ is a valid and reliable measure of GORD symptoms that can be used as a study outcome in clinical trials.