Translation and validation of the Norwegian version of the Coronary Revascularisation Outcome Questionnaire

Background: Health-related quality of life (HRQOL) questionnaires are increasingly used as outcome measures in research and clinical practice to assess treatment effectiveness in coronary heart disease (CHD) alongside traditional outcome measures. The Coronary Revascularisation Outcome Questionnaire (CROQ) is a patient-reported outcome measure (PROM) to evaluate health outcomes and HRQOL before and after coronary artery bypass grafting surgery (CABG) and percutaneous coronary intervention (PCI). Aim: To translate the CROQ-PCI from English into Norwegian and test its psychometric properties. Methods: Independent forward and backward translation was done following international guidelines. The CROQ was then pretested with both healthcare professionals and patients before the psychometric properties were field tested in a sample of patients who had undergone PCI. Psychometric testing included an evaluation of: acceptability; tests of scaling assumptions; reliability; content validity; construct validity based on within-scale analyses; and construct validity based on comparisons with external measures. Results: 171 of 258 (66%) invited patients participated. The CROQ was acceptable to patients (low proportion of missing data and good response rate), reliable (good internal consistency and test-retest reliability for all scales), had good content validity (reported by both patients and healthcare professionals) and good construct validity (convergent validity with the SF-12 and Seattle Angina Questionnaire, known groups validity and factor analysis). Conclusion: The Norwegian version of CROQ-PCI is a reliable and valid PROM for assessing HRQOL in CHD patients. Further testing of its responsiveness and ability to detect change is needed before recommending its use in Norwegian clinical practice and research.