Content validity of the birth beliefs scale following a translation into German

This study aimed to translate and adapt the Birth Beliefs Scale (BBS) into German, focusing on content validity of the German version (G-BBS). The BBS, originally developed in Israel and validated in English, assesses women's basic beliefs about childbirth.

The translation and adaption followed the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guideline. Four translators were involved in forward and backward translation. Content validity procedures were aligned with COSMIN (COnsensus-based Standards for the selection of health Measurement Instruments) methodology. Cognitive debriefing involved 10 experts and 30 pregnant women for content validity. Both groups rated relevance, clarity as an indicator of comprehensibility, and overall comprehensiveness.

Minor harmonization adjustments were required to enhance clarity, particularly in specific items, but no major revisions were required. Content validity index scores were acceptable for 10 out of 11 items during harmonization. During the validation process minor revisions were needed for two items. Inter-rater agreement from the expert panel and the target group exceeded 80%, confirming the adaption's clarity and cultural relevance. Pregnant participants rated the scale as easy to use. Overall comprehensiveness was confirmed by both groups.

The BBS was systematically translated and adapted for German users, incorporating harmonization procedures to ensure conceptual equivalence as well as linguistic and cultural appropriateness throughout the translation process. Further psychometric validation in a larger sample is needed to evaluate structural properties and measurement performance.