Validation of an instrument to determine oral health knowledge, attitudes, and practices during pregnancy

Background Oral health of the mother-infant dyad is important to preserve general health. However, there are few instruments in Spanish for the evaluation of knowledge, attitudes and practices that determine this construct. Therefore, this research aimed to develop and evaluate the psychometric properties of the Maternal Oral Health Knowledge, Attitudes and Practices Questionnaire (CAPSOM in Spanish). Methods In this instrument development study that carried out in 2018–2019, involving pregnant women between the ages of 18 and 45 in the city of Leon, Guanajuato, Mexico. The sample size was calculated based on 10 women per questionnaire item (n = 10 k). The study used Cronbach’s alpha, the modified Lawshe test of validity criteria, factor analysis, and the level of difficulty and discrimination of the items. Results 207 women took part with their signed, informed consent (25 ± 6 years). The internal consistency of the instrument, both total and by dimension was α = 0.70, α = 0.66 knowledge, α = 0.74 attitudes, and α = 0.66 practices. Values of Content Validity Ratio’ ≥ 0.60 were obtained for the final 10 items and Content Validity Index’ = 0.90. The average difficulty index of items was 0.40, and there were significant differences (Kruskall–Wallis, p < 0.001) in the discrimination test. Factor analysis demonstrated three main components. Conclusions A valid and reliable 10-item Spanish questionnaire was designed to measure pregnant women’s oral health knowledge, attitudes, and practices.