Development and assessment of a knowledge, attitude, and practice (KAP) questionnaire for genetic counselees with preimplantation genetic testing (PGT) indications

Background: Preimplantation genetic testing (PGT) can reduce the risk of familial genetic diseases, chromosome abnormalities, and recurrent abortions. It is unclear whether genetic counselees with PGT indications understand and accept the implications of PGT. A well-developed and validated tool is needed to evaluate the knowledge, attitude, and practice (KAP) levels of genetic counselees with PGT indications. The purpose of this study was to develop and validate a PGT KAP questionnaire (PGT-KAP-Q) for genetic counselees with PGT indications. Methods: First, we established an item pool based on a literature review and qualitative interviews. Second, we developed the PGT-KAP-Q using the Delphi method. Third, we evaluated the quality of the questionnaire using item analysis and psychometric evaluation. The item analysis included extreme value comparison, application of the correlation and Cronbach's alpha (alpha) coefficient methods, and factor analysis. We also evaluated the content and structural validity of the questionnaire, as well as the internal consistency, test-retest reliability, and split-half reliability. Findings: After the literature review and interviews, and based on three rounds of expert consultations, we formed a 43-item questionnaire. In the validity analysis, the item's content validity index (I-CVI) and the average scale level CVI (S-CVI/Ave) values (>0.78 and >0.95, respectively) confirmed the questionnaire's content validity. Exploratory factor analysis showed that all 43 items had strong factor loadings (>0.4), and the three factors of the PGT-KAP-Q explained 51.97 % of the total variance. The Cronbach's alpha coefficient for the questionnaire was 0.95 (p < 0.05), the split-half reliability was 0.76 (p < 0.05) and the test-retest reliability coefficient was 0.78 (p < 0.05). Interpretation: The 43-item PGT-KAP-Q for genetic counselees with PGT indications is reliable and valid. It contains a moderate number of items, is easy for patients to understand and accept, and can be used for clinical research and applications.