[Reliability and validity of Turkish version of COPD assessment test]

This study is aimed to evaluate the reliability and validity of the Turkish version of chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) in seven centers.

321 patients between 4-75 years of age, diagnosed and staged by Global Initiative for Obstructive Lung Disease (GOLD) 2011 criteria were included. The Breathlessness, Cough, Sputum scale (BCSS), mMRC (Modified Medical Research Council ) dyspnea index, St. George Respiratory Questionnaire (SGRQ), CAT and Short Form-36 (SF-36) were used concurrently. In the statistical analyses, internal consistency, item-total score correlation, explorative factor analysis, correlation with other scales were calculated.

The mean age was 62.4 ± 8.9 years and 89.7% of the patients were male (n= 288). Mean FEV1% was 51.9 ± 19.2 and most of the patients were in Stage 3. CAT total score was 17.8 ± 9.5. In the internal consistency, Cronbach alpha coefficient was found as 0.9116 and item-total score correlation coefficients were between 0.62-0.79 and all were statistically significant (p< 0.0001). The correlation of the test-retest score calculated after two weeks with the initial score was 0.96 (p< 0.0001). In the structural validity, factor analysis with principle component analysis and varimax rotation was performed. One factor solution was achieved with eigenvalue of 4.956 and it represented 61.9% of the total variance. All the items were contained in the factor and the factor loads were between 0.71-0.85. The correlation coefficients of CAT with other indexes were moderate to good. The discrimination of CAT among disease stages has been shown to be significant (p< 0.0001) and a significant correlation was found with pulmonary function tests (p< 0.0001).

It is demonstrated The Turkish version of COPD Assessment Tool is reliable and valid.