Evaluation of the Health Belief Model and decision making regarding amniocentesis in women of advanced maternal age.

The Health Belief Model (HBM) was developed as an attempt to explain an individual's decision regarding obtaining preventive health care. This model was applied to predict the decisions of women of advanced maternal age regarding their obtaining amniocentesis in a one-year study conducted in Toledo, Ohio. A questionnaire based on the HBM was administered to a sample of 98 pregnant women of advanced maternal age. A total of 96 questionnaires were eligible for inclusion in the study. Sixty-one women reported that they would have amniocentesis, 22 would not, and 13 were unsure. A multivariate analysis of variance among amniocentesis decision groups was performed using the health belief components (perceived susceptibility, perceived seriousness, perceived benefit, perceived barrier) and knowledge as variables. There was a significant difference (Wilks' criterion, p less than .0001) among the three decision groups, but the differences were in the health belief components and not in knowledge. A stepwise discriminant function analysis was used to classify subjects on the amniocentesis decision. Of the variables examined, only the HBM component perceived benefit factor was a significant discriminant (p = .0001). It is not necessarily the lack of knowledge that prevents women who are at risk because of advanced maternal age from having amniocentesis but their perceptions regarding amniocentesis. Genetic counselors need to focus more on exploring the perceptions of amniocentesis benefits in this population to facilitate the decision making process.