Massachusetts General Hospital Hairpulling Scale: Validity and Reliability Study of the Turkish Form

The aim of this study is to analyze the validity and reliability of the Turkish form of Massachusetts General Hospital Hairpulling Scale (MGH-HPS), which is used to measure the severity of Trichotillomania (TTM).

Fifty patients diagnosed with TTM according to the DSM-5 diagnostic criteria and fifty healthy controls participated in the study. The participants were asked to complete a sociodemographic questionnaire, the MGH-HPS-TR, the Clinical Global Impression (CGI), the Beck Depression Inventory (BDI), the Beck Anxiety Inventory (BAI) and the Barratt Impulsiveness Scale (BIS-11). The construct validity and the criterion validity of the MGH-HPS-TR were determined by means of exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. The reliability analysis of the MGH-HPS-TR was assessed by calculating the Cronbach's α coefficient and the item total correlation coefficient. The values for the area under the curve (AUC), sensitivity and specificity were based on the ROC analysis.

AFA and CFA results indicated a single factor structure with 7 items explaining 82.5% of the variance. The item/factor loadings were satisfactory with the best fit indeces. Correlations were found between the scores on the MGH-HPS-TR and the other scales used for criterion validity analyses. The internal consistency and the item-total correlation coefficients of the scale were found to be satisfactory. Based on a cut of point of ≥ 9, the scale had high power for discriminating between the patient and the control groups and high sensitivity and specificity.

This study showed that the MGH-HPS-TR can be used as a valid and reliable psychometric tool in Turkey.