Factors affecting decisions to accept or decline cystic fibrosis carrier testing/screening: a theory-guided systematic review.

PURPOSE: To assess factors affecting individuals' decision to accept or decline cystic fibrosis carrier testing/screening, as reported in studies published until December 2006. The Health Belief Model guided classification of each factor, and the studies' methodological quality was assessed.
METHODS: A three-stage search and retrieval process, alongside application of specific inclusion/exclusion criteria, yielded 40 studies (in 35 articles). For each reviewed study, authors abstracted and organized selected data into a matrix and assigned a methodological quality score.
RESULTS: The four most frequently identified acceptance factors included three Health Belief Model factors and one non-Health Belief Model factor: perceived benefits of undergoing cystic fibrosis carrier testing/screening, weaker perception of barriers to cystic fibrosis carrier testing/screening, fewer/no children or desiring children, and research-related factors (non-Health Belief Model factor construct). All four most frequent factors associated with declining testing were Health Belief Model factor constructs: perceived barriers to obtaining cystic fibrosis carrier testing/screening, parity, lack of knowledge, and weaker perception of benefits of undergoing cystic fibrosis carrier testing/screening. The average methodological quality of the studies was 10.2 (SD=3.2; range, 5-18 points).
CONCLUSIONS: The methodological and theoretical quality of this body of literature could be substantially improved if researchers employed theory-based approaches, tested (and reported) the validity/reliability of their own data, and employed multivariate statistical analyses and/or better controlled research designs. Improving the quality of future studies may allow better inferences regarding the relative contribution of each factor identified in this review to individuals' decision-making process.