Validity and reliability of a breast cancer knowledge test

A study was made to develop and test a tool to measure a subject's knowledge about breast cancer screening in order to implement effective strategies for prevention and early detection. The Breast Cancer Knowledge Test measures a subject's knowledge about detection and screening practices. The instrument is an expansion of Stillman's Knowledge Questionnaire. A 30-item test was designed and pretested. Four nationally recognized experts in cancer control determined content validity. Reliability testing then was done with a sample of 101 women 50 years of age and older. The complete posttested 18-item instrument is reported here. Correlational analyses were done between the total scores on the Breast Cancer Knowledge test and subjects' practice of screening behaviors. Findings indicate that more knowledge of breast cancer screening is associated with use of mammography and obtaining a professional examination, but not with the practice of breast self-examination.