Coronary revascularisation outcome questionnaire: validation study of the Serbian version

To translate, culturally adapt and validate the Coronary Revascularisation Outcome Questionnaire (CROQ), a disease-specific tool for measuring health-related quality of life (HRQoL) in patients with ischaemic heart disease (IHD), into Serbian language (CROQ-S).

Validation study was performed at the Clinic for Cardiac Surgery and Clinic for Cardiology, University Clinical Centre of Serbia. We included a convenience sample of 600 patients with IHD divided into four groups. Acceptability, reliability and validity of the CROQ-S were assessed.

CROQ-S was acceptable to patients as demonstrated by less than 1% of missing data for each single item. Cronbach's Alpha was higher than the criterion of 0.70 for all scales in each version except the Cognitive Functioning scale which only met this criterion in the CABG pre-revascularisation version. Mean values of item-total correlations were greater than 0.30 for all scales except the Cognitive Functioning scale in both the pre-revascularisation groups. Compared to the original version, exploratory factor analysis in our study showed more factors; however, the majority of items had a factor loading greater than 0.3 on the right scale. Correlations of CROQ-S scales with the 36-Item Short Form Health Survey and Seattle Angina Questionnaire showed the expected pattern whereby scales measuring similar constructs were most highly correlated.

CROQ-S is an acceptable, reliable and valid disease-specific instrument for measuring HRQoL in this sample of Serbian speaking patients with IHD both before and after coronary revascularisation. However, the Cognitive Functioning scale did not meet all the psychometric criteria and further validation of its responsiveness is required.