Determining Psychometric Properties of the Persian Version of Demoralization Scale-II in Cancer Patients

Abstract

Background One of the emotional problems in patients experiencing cancer is demoralization syndrome. Concerning the importance of demoralization in cancer patients, having a valid and reliable scale for assessing this problem is crucial. A revised version of Demoralization Scale (DS-II) has been designed in 2016. It was necessary to determine its validity and reliability in population with different culture. This study aimed to determine the psychometric properties of the Persian version of DS-II (PDS-II) in Iranian cancer patients. Methods The study population comprised 170 Iranian cancer patients in Ardabil, Iran. To determine the psychometric properties of PDS-II, the content, convergent, construct, and discriminant validity, besides internal consistency, were evaluated. Results Regarding the high correlation of PDS-II with GAD-7, PHQ-9, BHS, and HADS, the convergent validity of the PDS-II was confirmed. Confirmatory factor analyses confirmed both the original 2-factor and one-factor models of PDS-II. Internal discriminant validity of the PDS-II was not confirmed because the Average Variance Extracted from two dimensions of PDS-II (AVE = 0.31 and 0.37) was less than the square correlation between these two dimensions (r2 = 0.79). As the patients with a low Karnofsky score acquired more demoralization (p < 0.0001), the external discriminant validity of PDS-II was confirmed. Cronbach α coefficient was 0.88 for the PDS-II. Conclusions PDS-II is a valid and reliable scale for measuring demoralization among Iranian people with cancer. However, there is a high overlap between the two dimensions of PDS-II.