The Reflux Disease Questionnaire: a measure for assessment of treatment response in clinical trials

Michael Shaw, John Dent, Timothy Beebe, Ola Junghard, Ingela Wiklund, Tore Lind, Folke Johnsson, Michael Shaw, John Dent, Timothy Beebe, Ola Junghard, Ingela Wiklund, Tore Lind, Folke Johnsson

Abstract

Background: Critical needs for treatment trials in gastroesophageal reflux disease (GERD) include assessing response to treatment, evaluating symptom severity, and translation of symptom questionnaires into multiple languages. We evaluated the previously validated Reflux Disease Questionnaire (RDQ) for internal consistency, reliability, responsiveness to change during treatment and the concordance between RDQ and specialty physician assessment of symptom severity, after translation into Swedish and Norwegian.

Methods: Performance of the RDQ after translation into Swedish and Norwegian was evaluated in 439 patients with presumed GERD in a randomized, double-blind trial of active treatment with a proton pump inhibitor.

Results: The responsiveness was excellent across three RDQ indicators. Mean change scores in patients on active treatment were large, also reflected in effect sizes that ranged from a low of 1.05 (dyspepsia) to a high of 2.05 (heartburn) and standardized response means 0.99 (dyspepsia) and 1.52 (heartburn). A good positive correlation between physician severity ratings and RDQ scale scores was seen. The internal consistency reliability using alpha coefficients of the scales, regardless of language, ranged from 0.67 to 0.89.

Conclusion: The results provide strong evidence that the RDQ is amenable to translation and represents a viable instrument for assessing response to treatment, and symptom severity.

Figures

Figure 1
Figure 1
Responsiveness of GERD Score.

References

    1. Dent J, Armstrong D, Delaney B, Moayyedi P, Talley NJ, Vakil N. Symptom evaluation in reflux disease: workshop background, processes, terminology, recommendations, and discussion outputs. Gut. 2004;53:iv1–24. doi: 10.1136/gut.2003.034272.
    1. U.S. Department of Health and Human Services, Food and Drug Administration Guidance for Industry. Patient reported outcome measures: use in medical product development to support labeling claims. 2006. (accessed 21 January 2008).
    1. Shaw M, Talley NJ, Beebe T, Rockwood T, Carlsson R, Adlis S, Fendrick AM, Jones R, Dent J, Bytzer P. Initial validation of a diagnostic questionnaire for gastroesophageal reflux disease. Am J Gastroenterol. 2001;96:52–57. doi: 10.1111/j.1572-0241.2001.03451.x.
    1. Johnsson F, Hatlebakk JG, Klintenberg AC, Román J, Toth E, Stubberöd A, Falk A, Edin R. One-week esomeprazole treatment: an effective confirmatory test in patients with suspected gastroesophageal reflux disease. Scand J Gastroenterol. 2003;38:354–359. doi: 10.1080/00365520310002139.
    1. Johnsson F, Hatlebakk JG, Klintenberg AC, Román J. Symptom-relieving effect of esomeprazole 40 mg daily in patients with heartburn. Scand J Gastroenterol. 2003;38:347–353. doi: 10.1080/00365520310002157.
    1. Lundell LR, Dent J, Bennett JR, Blum AL, Armstrong D, Galmiche J-P, Johnson F, Hongo M, Richter JE, Spechler SJ, Tytgat GN, Wallin L. Endoscopic assessment of esophagitis: clinical and functional correlates and further validation of the Los Angeles classification. Gut. 1999;45:172–180.
    1. Jaeschke R, Singer J, Guyatt G. Measurement of health status. Ascertaining the minimal clinically important difference. Control Clin Trials. 1989;10:407–415. doi: 10.1016/0197-2456(89)90005-6.
    1. Juniper EF, Guyatt GH, Willan A, Griffith LE. Determining a minimal important change in a disease-specific quality of life questionnaire. J Clin Epidemiol. 1994;47:81–87. doi: 10.1016/0895-4356(94)90036-1.
    1. Lydick E, Epstein RS. Interpretation of quality of life changes. Qual Life Res. 1993;2:221–226. doi: 10.1007/BF00435226.
    1. Guillemin F, Bombardier C, Beaton D. Cross-cultural adaptation of health-related quality of life measures: literature review and proposed guidelines. J Clin Epidemiol. 1993;46:1417–1432. doi: 10.1016/0895-4356(93)90142-N.
    1. Guyatt GH, Juniper EF, Walter SD, Griffith LE, Goldstein RS. Interpreting treatment effects in randomized trials. BMJ. 1998;316:690–693.
    1. Kazis LE, Anderson JJ, Meenan RF. Effect sizes for interpreting changes in health status. Med Care. 1989;27:S178–189. doi: 10.1097/00005650-198903001-00015.
    1. Cronbach LJ. Coefficient alpha and the internal structure of tests. Psychometrika. 1951;16:297–334. doi: 10.1007/BF02310555.
    1. Carmines EG, Zeller RA. Sage University Paper series on Quantitative Applications in the Social Sciences, 07–17. London: Sage Publications; 1979. Reliability and validity Assessment.
    1. Cohen J. Statistical power analysis for the behavioral sciences. New York: Academy Press; 1977.
    1. McColl E, Junghard O, Wiklund I, Revicki DA. Assessing symptoms in gastroesophageal reflux disease: how well do clinicians' assessments agree with those of their patients? Am J Gastroenterol. 2005;100:11–18. doi: 10.1111/j.1572-0241.2005.40945.x.
    1. Streiner DL, Norman GR. Health measurement scales: a practical guide to their development and use. 2. Oxford: Oxford University Press; 1995.

Source: PubMed

3
Sottoscrivi