HMORN 2008 -Poster Presentations auditing and surveys of staff we present information demonstrating how the VDW is used at the 3 HMOs.Conclusions: The original intent of the VDW was to increase efficiency in the use of data on multi-site studies.However, single site studies can also gain efficiencies from using the VDW and at some HMOs the VDW has become the first data source to use for almost all research.The VDW advantages of standard data structures and standard methods are also useful for single site projects.

OBJECTIVE:To compare the rate of Papanicolaou testing in a population-based sample of women with medical documentation of 1) total hysterectomy for benign conditions, 2) total hysterectomy for malignant conditions, and 3) hysterectomy with cervix intact to rates among women who had not had a hysterectomy. METHODS:The Marshfield Epidemiologic Study Area was used to identify a retrospective cohort of women with hysterectomies age-matched to women without hysterectomies. This study compares the Papanicolaou test rate per year (outcome) by hysterectomy status (exposure) for women with total hysterectomy for benign reasons (n=197), total hysterectomy for malignancy (n=75), supracervical hysterectomy (n=43), and no hysterectomy (n=315). RESULTS:Compared with women who did not have a hysterectomy (nonexposed), women with a hysterectomy (exposed) for benign reasons had significantly fewer Papanicolaou tests; on average, one less test every 3 years (mean difference=-0.34 tests/year, P < .001). Contrary to this, women with a malignancy-related hysterectomy had significantly more tests than their nonexposed counterparts (mean difference=0.87 tests/year, P < .001); nearly one additional test per year. Finally, women with supracervical hysterectomies had the same rate of testing as their nonexposed counterparts (mean difference=-0.03 tests/year, P=.62); on average, one test every 2.5 years. CONCLUSION:This study demonstrates that Papanicolaou testing rates vary by type and reason for hysterectomy. Women with hysterectomies for benign reasons may be receiving from two to three times as many tests as needed. Notably, women with intact cervices following hysterectomy have similar testing rates (one every 2.5 years) as women without hysterectomies. This has direct implications for leaving a woman's cervix intact given normal cytology at the time of hysterectomy.

To capitalize on Marshfield Clinic's advantages for population-based health research, we developed the Marshfield Epidemiologic Study Area (MESA). Marshfield Clinic is an integrated system consisting of a large multispecialty clinic and 23 affiliated clinics. Clinic physicians provide virtually all of the medical care, both inpatient and outpatient, for residents of the area. MESA consists of 14 ZIP codes in which over 95% of the 50,000 residents and most significant health events are captured in Marshfield Clinic databases, including all deaths, 94% of hospital discharges, and 92% of medical outpatient visits. MESA exemplifies the research potential of integrated medical care systems and the efforts required to realize that potential, Because it is representative of a defined population and provides an unselected sample of patients, MESA is well suited for epidemiologic research and research elucidating the clinical spectrum and natural history of diseases and the effectiveness of treatment.