Background: Despite eligibility for a screening mammogram once every 2 years from 1991 to 1997, only a small percentage of Medicare women utilized this benefit. We examined mammography use among 388,707 North Carolina Medicare women from 1994 to 1997 to identify characteristics of one-time and never users of mammography.
Methods: Data were obtained from North Carolina Medicare mammography claims and enrollment files from 1994 to 1997. Women ages 65+ as of 01/01/1994, continuously enrolled in Medicare from 1994 to 1997, and alive as of 12/31/1997 were included in the sample (n = 388,707). Mammogram use was categorized as never, once, or at least twice during 1994/1995 and 1996/1997. Women with at least one mammography claim during 1994/1995 and at least one mammography claim during 1996/1997 were called repeat users, women with one mammography claim during the 4 years were labeled one-time users, and women with zero mammography claims during the 4 years were termed never users. Multivariate logistic regression analyses were conducted to determine associations between characteristics and mammography frequency.
Results: Biennial mammography claims data rates were 35.3% in 1994/1995 and 41.8% in 1996/1997. Compared with all other users, one-time users (n = 108,899) were more likely to be ages 65-74 (vs 75-84 and 85+), live in an urban versus rural county, and be eligible for Medicare only versus Medicare and Medicaid. Never users (n = 184,545) were more likely to be ages 85+, be non-Caucasian, live in a rural county, and be eligible for both Medicare and Medicaid versus Medicare.
Conclusions: These results demonstrate different demographic characteristics for one-time and never mammography users. This approach of using multiple years of claims data to segment the targeted population provides the opportunity to tailor interventions to subgroups.
Copyright 2001 American Health Foundation and Academic Press.