Validation of an anxiety scale for prenatal diagnostic procedures

To perform a cross-cultural adaptation of the Prenatal Diagnostic Procedures Anxiety Scale questionnaire for application in the Brazilian cultural context.

The translation and back translation processes followed internationally accepted criteria. A committee of experts evaluated the semantic, idiomatic, experimental and conceptual equivalence, proposing a pre-final version that was applied in 10.0% of the final sample. Afterwards, the final version was approved for the psychometric analysis. At that stage, 55 pregnant women participated which responded to the proposed Brazilian version before taking an ultrasound examination at a public hospital in Santa Catarina, in the year of 2017. The Edinburgh Postnatal Depression Scale was used as an external reliability parameter. The internal consistency of the instrument was obtained by Cronbach's alpha. Validation was performed by exploratory factorial analysis with extraction of principal components by the Kaiser-Guttman method and Varimax rotation.

The Cronbach's alpha value of the total instrument was 0.886, and only the percentage of variance from item 2 (0.183) was not significant. The Kaiser-Guttman criterion defined three factors responsible for explaining 78.5% of the variance, as well as the Scree plot. Extraction of the main components by the Varimax method presented values from 0.713 to 0.926, with only item 2 being allocated in the third component.

The Brazilian version is reliable and valid for use in the diagnosis of anxiety related to the performance of ultrasound procedures in prenatal care. Due to the lack of correlation with the rest of the construct, it is suggested that item 2 be removed from the final version.