In addition, individuals whose Social Security number or Medicare identification number
was stored on the affected parts of the network will receive 12 months of credit monitoring.
The two sources of data for this study were the SEER data from NCI and Medicare hospitalization data maintained by HCFA.(1) The SEER data have been collected since 1973 and, for each patient, contain: age, race, and sex; each occurrence of a primary incident cancer (recurrent and metastatic sites are not collected); year of diagnosis; site of report (hospital, physician office, etc.); stage of disease; type of surgery performed; and for this file only, the person's unique Medicare identification number.
We used each individual's Medicare identification number to link cases in SEER with Medicare hospitalization data.
Approximately 94 percent of SEER cases have a Medicare identification number (Potosky et al., 1993).
These cases could not be matched to Medicare hospitalization data because the SEER file did not have a Medicare identification number for these persons.
After identifying all claims, claims files were linked by the unique Medicare identification number
to the history file (HISKEW) in order to identify the actual persons who had the KR and to retrieve their demographic characteristics.
But analysts said the Medicare identification numbers
exposed can be valuable to criminals and could pose potential financial and medical problems to those affected.
Medicare identification numbers were solicited from the sample members, and utilization and expenditure data were derived from the Health Care Financing Administration's (HCFA) Medicare Automated Data Retrieval System (MADRS) Part A - Part B skeleton file.
For the main impact analysis, Medicare identification numbers could not be obtained for 41 CCRC residents (2.5 percent of the actual cohort) and for 339 traditional community residents (24.6 percent of the actual cohort).
Medicare identification numbers could only be obtained for 87 CCRC residents in the last-year-of-life sample (24 percent of the CCRC death sample).
A two-step process was used to impute hospital and home health care uses where data were missing for members in the traditional community residence sample whose Medicare identification numbers could not be obtained.