Kaiser Permanente Northwest

KAISER PERMANENTE NORTHWEST

Kaiser Permanente Northwest (KPNW) serves over 440 000 members, approximately 25% of the population of the membership area, which includes the Portland (Oregon)–Vancouver (Washington) metropolitan area (Selby et al., 2005). The distribution of the membership by age, race and gender proportion-ately reflects that of the population of the Portland– Vancouver area. Services provided by KPNW include hospital and surgical care, maternity care, X-rays, mammography, laboratory testing, allergy testing, home healthcare, doctor office visits, well-baby care, mental health and, unique to KPNW, dental care. Most of the members are covered by a prepaid drug benefit; for the less than 10% without the drug bene-fit, prescriptions are provided at or below prevailing community charges.

Databases available at KPNW include the Outpa-tient Pharmacy System, which began in 1986 and records all prescriptions dispensed by its outpatient pharmacies. Data include drug name, NDC code, quantity dispensed, days supplied, refill number, date and other product information. The automated Inpa-tient Medication System captures all inpatient medica-tion orders, storing the history of each hospitalization in a unique hospital stay number that is generated on admission.

The KPNW also maintains an Adverse and Aller-gic Drug Event Reporting database, from which it prepares reports for the local KPNW Formulary and Therapeutics Committee, and submits data to the MedWatch system of the US Food and Drug Administration (FDA).

Other data systems include The Inpatient Admis-sion/Discharge/Transfer System, which provides data on hospitalizations in Kaiser and non-Kaiser hospi-tals, and includes information on ambulatory surgical and other major procedures performed in the hospi-tals since the mid-1960s. EpicCare® is an automated medical record system useful for clinicians providing direct patient care. It has been used for all outpatient care since 1997, and contains records for more than 900 000 KPNW members (Selby et al., 2005). Spin-offs of subsets of these files can make these data accessible for research purposes.

EpicCare® has served as the prototype for HealthConnect®, which is currently being imple-mented across the Kaiser Permanente Program. This new program collects information not currently collected under a claims-based system, such as orders for prescriptions (whether or not they were filled) and laboratory tests (whether or not they were completed), and telephone consults. This information will allow for studies of adherence to therapy and quality of care and of safety in large populations (Selby et al., 2005).

Additional databases cover the areas of dental care, emergency psychiatric calls and contacts, emergency department visits, laboratory, cytology and histol-ogy procedures and results, patient-specific radiol-ogy department data, including radiology, ultrasound, magnetic resonance imaging, nuclear medicine, and computerized tomography, prenatal screening, immu-nization, and a continuing care service database of home care services for homebound members. A Medi-care Plus II Database contains data from question-naires, distributed annually to participants, which measure levels of functioning and depression using standardized instruments.

Multiple disease registries are maintained by KPNW as well, including cancer, benign breast disease, breast cancer family registry, diabetes and rheumatology registries. A genetics registry of more than 5 million members of the Northwest Division and the Northern and Southern California regions was begun in 1986, with Hawaii joining this registry in 1992.

The KPNW Center for Health Research also maintains multiple databases that provide data on outpatient utilization, information on health status and behaviours of members, satisfaction with care provided, and other information obtained from surveys based on a sampling of the KPNW member-ship. The Common Control Pool database contains basic demographic and eligibility data for virtu-ally all people who have been members of KPNW. A Pregnancy Registry identifies pregnant KPNW members, using laboratory data, ultrasound reports and clinic visits, enabling the tracking of all preg-nancy outcomes. The KPNW immunization database contributes data to the Vaccine Safety DataLink Project, funded by the US Center for Disease Control and Prevention (CDC) (see below).

The KPNW membership mostly reflects the popu-lation of the area it serves, although again the poor and the very wealthy are under-represented. The membership is relatively stable after one year; the median length of enrollment retention is more than 5 years. The use of a unique medical record number allows the linkage of drug dispensing with inpatient and outpatient files, and it is possible to calculate prevalence and incidence rates. Access to primary medical records permits validation of diagnostic infor-mation and gathering of information on confounding and demographic variables, which, with the excep-tion of age and gender, are absent from the available databases.

The Kaiser Permanente formularies are limited, with the newest and/or most expensive drugs unlikely to be listed. It is also likely that only one brand of a particular drug is available.