Cultural adaptation and content validation of the Single-Question for screening alcohol abuse

Objective Describing the stages of translation, cultural adaptation and content validation of the Single-Question into Brazilian Portuguese, which will be named Questão Chave. Method This study is a cultural adaptation. The instrument was translated into Portuguese as two independent versions which led to a synthesis of translations (S1), and later to the synthesis S2, which was then submitted to evaluation by a Committee of Expert Judges in the area of alcohol use and instrument validation. The Content Validity Index and Kappa agreement coefficient were calculated from this evaluation. Results The judges evaluated the Questão Chave regarding the clarity of the sentence and aspects related to the quality of the translation (cultural adaptation, preservation of original meaning and correct use of technical terms). The Content Validity Index was 1 for clarity of sentence and correct use of technical terms, and 0.8 for adaptation and preservation of the original meaning. The Kappa index for concordance among the judges was 0.83. After an adjustment proposed by the judges, the S3 version was originated. Conclusion The Questão Chave had its content validity confirmed, which supports future studies that aim for its application in the target population to verify their psychometric properties.