Strategies for managing breast cancer risk after the menopause

Validity assessment of the Breast Cancer Risk Reduction Health Belief scale

BACKGROUND

: Women at increased risk of breast cancer (BC) are not widely accepting of chemopreventive interventions, and ethnic minorities are underrepresented in related trials. Furthermore, there is no validated instrument to assess the health-seeking behavior of these women with respect to these interventions.

METHODS

: By using constructs from the Health Belief Model, the authors developed and refined, based on pilot data, the Breast Cancer Risk Reduction Health Belief (BCRRHB) scale using a population of 265 women at increased risk of BC who were largely medically underserved, of low socioeconomic status (SES), and ethnic minorities. Construct validity was assessed using principal components analysis with oblique rotation to extract factors, and generate and interpret summary scales. Internal consistency was determined using Cronbach alpha coefficients.

RESULTS

: Test-retest reliability for the pilot and final data was calculated to be r = 0.85. Principal components analysis yielded 16 components that explained 64% of the total variance, with communalities ranging from 0.50-0.75. Cronbach alpha coefficients for the extracted factors ranged from 0.45-0.77.

CONCLUSIONS

: Evidence suggests that the BCRRHB yields reliable and valid data that allows for the identification of barriers and enhancing factors associated with use of breast cancer chemoprevention in the study population. These findings allow for tailoring treatment plans and intervention strategies to the individual. Future research is needed to validate the scale for use in other female populations. Cancer 2009. (c) 2009 American Cancer Society.

Body mass index and use of mammography screening in the United States

BACKGROUND

Obese and underweight women may be less likely to seek cancer screening because of health status, self-perception, and body image related to non-desirable weight. This study examined the relationship between body mass index (BMI) and mammography screening, using the data from the year 2000 United States National Health Interview Survey.

METHODS

This study included 7692 white and 1496 black female participants aged 40-80, who were randomly selected. Body mass index (kg/m2), based on self-reported weight and height, was compared between women with and without a mammogram in the past 2 years using logistic regression.

RESULTS

Compared to women with normal body mass index, underweight and extremely obese women were more likely to have no screening mammograms in the past 2 years (odds ratio (OR) = 1.8, 95% confidence interval (CI), 1.2-2.6 for underweight women; odds ratio = 1.3, 95% confidence interval, 1.0-1.8 for extremely obese women). When data were analyzed by race, the odds ratio estimates were 1.8 for underweight white women (95% confidence interval, 1.3-2.7) and 1.4 for extremely obese white women (95% confidence interval, 1.0-1.9). The corresponding odds ratio estimates were close to 1.0 for black women.

CONCLUSIONS

Underweight and extreme obesity may increase the risk of underusing screening mammography. The association between body mass index especially underweight and underuse of mammography might exist primarily in white women.