Validity and Reliability of the Persian Version of Emotion Thermometers in Iranian Advanced Cancer Patients

The emotion thermometers (ET) is one of the main tools that is recommended, but it has not been examined in Iran. The aim of this research was to evaluate the psychometric characteristics of the Persian form of ET in advanced cancer patients. In this cross sectional study, 150 advanced cancer patients, who were referred to palliative care at Firoozgar Hospital from September to November 2017, were selected through convenience sampling method. Then, the instrument was translated into Persian and back-translated and its content and face validities were examined. To ensure divergent, convergent, and predictive validity, McGill quality of life questionnaire and hospital anxiety and depression scale were used. also, sensitivity and specificity were determined by using the receiver operating characteristics curve. Finally, to assess the reliability, the test-retest correlation was calculated via the Pearson correlation coefficient. The data were analyzed by SPSS 21 software (P < 0.01). The results of this study provided strong supports, which confirmed the content and face validities. Regarding the convergent and divergent validity, ET had a direct and strong relationship with HADS and all thermometers had a significant and reverse relationship with MQOL. The results of logistic regression showed that the model based on 5 variables of prediction could explain 65% of the variance of hospital anxiety variable and 51% of the variance of hospital depression. Using a cut-off of 3v4 on all thermometers against hospital anxiety, the optimal thermometer was the Anxiety Thermometer (specificity 68%, sensitivity 97%) and against the hospital depression scale, the optimal thermometer was the depression thermometer (specificity 74%, sensitivity 82%). Also, the results showed that the test-retest correlation coefficient varied from 0.81 to 0.88. This study has provided some evidence on the validity and reliability of the Persian form of ET as a sufficiently accurate way for identifying the distress of advanced cancer patients.