Abstract
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.
Acknowledgements
The authors gratefully acknowledge L. Rowe and A. Cagnazzo (Reckitt Benckiser) for critical review of the manuscript.
Disclosure statement
G. Smith, S.J. Thomas and J. Wilkinson are employees of Reckitt Benckiser. C. Reimer has received research funding from Reckitt Benckiser. P. Bytzer has served on an advisory board for Reckitt Benckiser and has received honoraria and research funding from Reckitt Benckiser. Milena Anatchkova, Ray Hsieh and William R Lenderking are employees of Evidera.
Funding
This study was funded in full by Reckitt Benckiser. Analysis, writing and editorial support were provided by Evidera; this support was funded by Reckitt Benckiser.