Measuring childbirth-related posttraumatic stress disorder: Psychometric properties of the Italian version of the City Birth Trauma Scale (City BiTS)

Objective: The City Birth Trauma Scale (City BiTS) assesses postpartum posttraumatic stress disorder (PTSD) based on the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria. Although it has been validated worldwide, predictive validity has not been previously examined. Moreover, no Italian version of the scale exists. This study aimed to test the bifactor latent structure and alternative models, internal consistency, test-retest reliability, convergent validity, divergent validity, and predictive validity of the City BiTS. Method: Women (N = 629) who had given birth within the past 3 months completed an online survey including sociodemographic and obstetric characteristics, the City BiTS, the Impact of Event Scale-Revised, and the Edinburgh Postnatal Depression Scale. After 3 months, women completed the City BiTS again and reported their intention to breastfeed during the 1-year postpartum. Results: Exploratory factor analysis confirmed the two-factorial structure. In confirmatory factor analysis, the two-factorial solution showed the best model fit. Internal consistency was good to excellent for the subscales and the total scale. Correlation analyses showed strong convergent validity with the Impact of Event Scale-Revised, high divergent validity with the Edinburgh Postnatal Depression Scale, high test-retest reliability, and good predictive validity with the intention to exclusively breastfeed. Moreover, the Birth-Related Symptoms subscale distinguished between different types of delivery. Conclusions: The City BiTS-Italian is the first measure evaluating and diagnosing childbirth-related PTSD symptoms based on Diagnostic and Statistical Manual of Mental Disorders (5th ed.) in Italy. The factorial structure and validity reported in other cultural contexts were confirmed; moreover, findings add evidence to the scale's temporal stability and predictive validity. Besides contributing to clinical purposes, the City BiTS-Italian will facilitate international comparability regarding the prevalence of PTSD following childbirth.