Validation of a measurement tool to assess awareness of breast cancer.

AIM Until now, there has been no universally accepted and validated measure of breast cancer awareness. This study aimed to validate the new Breast Cancer Awareness Measure (BCAM) which assesses, using a self-complete questionnaire, knowledge of breast cancer symptoms and age-related risk, and frequency of breast checking. METHODS We measured the psychometric properties of the BCAM in 1035 women attending the NHS Breast Screening Programme: acceptability was assessed using a feedback questionnaire (n=292); sensitivity to change after an intervention promoting breast cancer awareness (n=576), and test-retest reliability (n=167). We also assessed readability, and construct validity using the 'known-groups' method. RESULTS The readability of the BCAM was high. Over 90% of women found it acceptable. The BCAM was sensitive to change: there was an increase in the proportion of women obtaining the full score for breast cancer awareness one month after receiving the intervention promoting breast cancer awareness; this was greater among those who received a more intensive version (less intensive version (booklet): 9.3%, 95% confidence interval (CI): 4.5-14.1%; more intensive version (interaction with health professional plus booklet): 30%, 95% CI: 23.4-36.6%). Test-retest reliability of the BCAM was moderate to good for most items. Cancer experts had higher levels of cancer awareness than non-medical academics (50% versus 6%, p=0.001), indicating good construct validity. CONCLUSIONS The BCAM is a valid and robust measure of breast cancer awareness suitable for use in surveys of breast cancer awareness in the general population and to evaluate the impact of awareness-raising interventions.