Patterns and predictors of adherence to breast cancer screening recommendations in Alberta's Tomorrow Project

Abstract

Breast cancer screening is an important prevention component as it can reduce cancer mortality and improve survival. Understanding patterns of adherence to screening recommendations is essential to guide health promotion strategies and policy implementation efforts. The 1999 Alberta screening guidelines were used to determine screening status for eligible female participants in Alberta's Tomorrow Project (n = 4,972), a longitudinal province-based cohort. Screening patterns were derived based on screening status assessed at enrollment (2001-2008) and follow-up (2008-2011). Information on reason for screening was also collected at each time point. Multinomial logistic regression was used to assess potential predictors of adherence to screening recommendations. The majority of participants were up-to-date with screening at enrollment (79.3 %), and follow-up (75.2 %). Among all participants, 66.3 % were up-to-date at both time points (considered 'regular screeners'), 8.9 % were not up-to-date or never at enrollment but up-to-date at follow-up (considered 'new screeners'), 21.6 % were not up-to-date at follow-up (considered 'episodic screeners') and 3.2 % had never participated in screening (considered 'non-screeners'). Having a family doctor was the strongest factor associated with being a regular screener (OR (95 % CI): 0.37 (0.24 0.57) when compared with new screeners. Current smokers were more likely to be non-regular screeners. The primary reason for screening was routine screening or age. In conclusions, non-regular screening patterns were more prevalent among women without a family doctor. This finding suggests having a family doctor is an important mechanism to encourage screening. Further work is required to raise awareness of current recommendations and to understand and address reasons for non-adherence.

Keywords: Alberta’s Tomorrow Project; Breast cancer; Cohort; Mammography; Screening.

Fig. 1

Flow chart of Alberta’s Tomorrow Project participant selection.

Fig. 2

Reasons given for breast cancer screening tests at enrollment across screening patterns. Reasons for screening were reported at enrollment and the responses were allocated into three categories according to a priority hierarchy: (1) problem (previously detected lump or on hormone replace therapy or other breast problem); (2) family history of breast cancer; (3) routine screening or age (part of regular checkup or routine screening or age). Participants could select more than one category, but were assigned only one category based on the highest priority reason given.

Fig. 3

Forest plot of odds ratios (ORs) for predictors of breast cancer screening patterns. Regular screeners were used as the reference groups. ORs were mutually adjusted for participant’s enrollment (except having a family doctor which was measured at follow-up) characteristics which including age, residential area (rural; urban), marital status (divorced/ separated/ widowed/ single, never married; married/ living with partner), education level (high school or lower; college; university or post graduate education), employment status (not employed, student, home maker or other; retired; employed part-time; employed full-time), annual household income (<$70 000; ≥$70 000; cut-off was derived from the median Canadian family income in 2008), body mass index (BMI), smoking status (current smoker; current non-smoker), self-reported health status (fair/ poor; excellent/ very good/ good), family history of any cancer (no; yes), and currently having a regular family doctor (no; yes).