Outpatient and inpatient medical records related to diabetes diagnosis, treatment, and laboratory testing were requested for consenting women and reviewed by a trained physician adjudicator (KM, CL, SW, DB) at each site. Medical records of all self-reported incident and prevalent diabetes cases were requested and reviewed. The records of any participant from the No Diabetes Group who had only one fasting glucose value available, any fasting glucose value of >100 mg/dL, or who reported diabetes on the confirmation questionnaire were also requested and reviewed. If all of two or more fasting glucose values were <100 mg/dL and the participant reported no diabetes on the confirmation questionnaire, she was assumed without further review not to have diabetes.
The medical record review form included notations of diabetes on the problem list or as a diagnosis, the use of medications for diabetes (oral medications and/or insulin), glycosylated hemoglobin levels, fasting and casual plasma glucose values, and results of any oral glucose tolerance tests. Based on the medical records reviewed, the adjudicators recorded their summary impression about whether the participant had diabetes and listed the supporting diagnostic criteria on which their decision was based. Diabetes was defined at the study's inception in accordance with the American Diabetes Association definition[25 (link)] as one or more of the following found in the medical record: 1) Fasting plasma glucose >126 mg/dL, 2) Symptoms of diabetes (polyuria, polydipsia, and unexplained weight loss) plus casual plasma glucose concentration >200 mg/dL, 3) 2-hour postload glucose >200 mg/dL during an oral glucose tolerance test using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water, and 4) Treatment with insulin or an oral hypoglycemic agent.
All physician adjudicators participated in a training session in which 12 sample charts were reviewed and discussed. Furthermore, shortly after medical record abstraction was under way, quality assurance checks were conducted; a second adjudicator (KM) independently reviewed 12 randomly selected records (5 incident, 5 prevalent, and 2 nondiabetes cases) from each site and verified the summary impression of diabetes vs. no diabetes, as supported by the diagnostic elements listed above. Agreement between adjudicators regarding diabetes status was 100%. In addition to the quality assurance sample, the medical records of any discordant cases (WHI self-report of diabetes did not match summary impression from medical record review) were reviewed by a second physician adjudicator (KM), who made a final determination of diabetes status. The WHI cohort was also linked to Medicare data from 1991 to 2007. Of women aged 65 and older with a valid Social Security number, 196 were successfully matched to the Medicare enrollment file.
The medical record review form included notations of diabetes on the problem list or as a diagnosis, the use of medications for diabetes (oral medications and/or insulin), glycosylated hemoglobin levels, fasting and casual plasma glucose values, and results of any oral glucose tolerance tests. Based on the medical records reviewed, the adjudicators recorded their summary impression about whether the participant had diabetes and listed the supporting diagnostic criteria on which their decision was based. Diabetes was defined at the study's inception in accordance with the American Diabetes Association definition[25 (link)] as one or more of the following found in the medical record: 1) Fasting plasma glucose >126 mg/dL, 2) Symptoms of diabetes (polyuria, polydipsia, and unexplained weight loss) plus casual plasma glucose concentration >200 mg/dL, 3) 2-hour postload glucose >200 mg/dL during an oral glucose tolerance test using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water, and 4) Treatment with insulin or an oral hypoglycemic agent.
All physician adjudicators participated in a training session in which 12 sample charts were reviewed and discussed. Furthermore, shortly after medical record abstraction was under way, quality assurance checks were conducted; a second adjudicator (KM) independently reviewed 12 randomly selected records (5 incident, 5 prevalent, and 2 nondiabetes cases) from each site and verified the summary impression of diabetes vs. no diabetes, as supported by the diagnostic elements listed above. Agreement between adjudicators regarding diabetes status was 100%. In addition to the quality assurance sample, the medical records of any discordant cases (WHI self-report of diabetes did not match summary impression from medical record review) were reviewed by a second physician adjudicator (KM), who made a final determination of diabetes status. The WHI cohort was also linked to Medicare data from 1991 to 2007. Of women aged 65 and older with a valid Social Security number, 196 were successfully matched to the Medicare enrollment file.
