Design and psychometrics of post-traumatic stress disorder tool for children undergoing heart surgery

The aim of this study was to design and examine the psychometrics of post-traumatic stress disorder tool for children undergoing heart surgery

. Heart disease is one of the most important health issues and traumatic events that cause great harm to children, one of which is the experience of surgery. Therefore, we need a standard tool to assess post-traumatic stress disorder in children.

In this methodological study, researchers compiled a questionnaire for measuring post-traumatic stress disorder in children undergoing heart surgery. The questionnaire was provided to 10 experts to examine the validity. In the next step, 40 items, revised by experts, were examined for construct validity and reliability based on the responses of 200 children 12-18 years old to questionnaire. The data were analyzed in SPSS version 24 and LISREL version 10.

After preparing the draft, the questionnaire was given to 10 experts to determine face and content validity. For face validity, the impact score of the items was computed and due to similar meaning of some items they were merged. In order to determine the content validity, two indexes of content validity ratio (CVR) and content validity index (CVI) were considered. According to Lauche's table, items with a content validity ratio less than 0.62 were excluded (7 items), items with a content validity ratio greater than 0.79 were accepted, and items with a content validity ratio between 0.70 and 0.79 were revised. In the construct validity stage, to ensure the sufficient sample size, the Kaiser-Meier-Elkin (KMO) test was performed and the results of Bartlett's Sphericity test were significant (P≤0.0001). Finally, exploratory factor analysis was performed with Varimax rotation on 40 items, and 7 items with a factor loading of less than 0.4 were removed, and in the end, 33 items remained. To determine the reliability of the questionnaire using the internal consistency method, Cronbach's alpha of the questions were computed and it was above 0.80 for all items. The test-retest results confirmed the significant relationship between the pre-test and post-test scores in 7 factors of the questionnaire (P≤0.0001).

In order to achieve more accurate results in research, it is necessary to use valid and reliable tools. The results of this study showed the strength of the factor structure and acceptable reliability of the post-traumatic stress tool for children undergoing heart surgery. The tool designed in this study is valid and reliable and can be used to determine post-traumatic stress in children undergoing heart surgery.