Group Health Cooperative of Puget Sound (GHC) is a health maintenance organization (HMO), established in 1947, which provides health care on a prepaid basis to approximately 562 000 persons in Washington State, located in the northwestern corner of the United States.
GROUP HEALTH COOPERATIVE OF
PUGET SOUND
Group
Health Cooperative of Puget Sound (GHC) is a health maintenance organization
(HMO), established in 1947, which provides health care on a prepaid basis to
approximately 562 000 persons in Washington State, located in the northwestern
corner of the United States (Saunders Davis and Stergachis, 2005).
Three-quarters of these enrollees receive all their care at Group Health
facilities. A fifth of the total number of enrollees belong to a subsidiary of
GHC, established in 1990, which provides a ‘point of service’ option that
permits care from community providers other than Group Health providers. As the
point of service cover-age is more expensive than that provided by Group Health
providers, most of the coverage remains within the Group Health network.
Although the majority of enrollees receive health benefits through their place
of employment, coverage has been extended to 58 500 Medicare, 30 000 Medicaid
and 18 000 Washington Basic Health Plan recipients, thereby expanding its
membership to include elderly and low-income resi-dents (Saunders, Davis and
Stergachis, 2005).
GHC offers comprehensive health care coverage for outpatient
care, inpatient services, emergency care, mental health services, and
prescribed drugs, although the latter are not provided to Medicare enrollees
new to GHC since 1993. Nearly all benefit plans require small co-payments for
services, such as prescrip-tions, outpatient visits unrelated to preventive
care and emergency treatment. Coverage for outpatient drugs is controlled by
GHC’s drug formulary.
At
GHC, each enrollee is assigned a unique number, which remains with that person
even if the individual drops out of the plan and then rejoins the health system
at a later date. Multiple databases have been developed from the main database,
with an individual’s records linked through their unique number.
The
socio-demographic profile of GHC enrollees is generally comparable to that of
the population of the Seattle–Tacoma area, with the GHC enrollees some-what
better educated. The median income of both groups is similar, although the GHC
membership is less representative of the highest income category.
Multiple
database files exist, and date from vary-ing time-points. The current
enrollment file consists of some 562 000 individuals; historical files contain
records for some 2 million persons enrolled in GHC at any time since 1980
(Saunders, Davis and Ster-gachis, 2005). The Pharmacy file, dating from 1977,
contains records generated when prescriptions are filled. Drug data include
drug number, therapeutic class, drug form and strength, date dispensed,
quan-tity dispensed, cost to GHC, and refill indicator. The file currently
includes a field for number of days the medication should last. The hospital
database, dating back to the early 1970s, includes diagnoses, proce-dures,
diagnostic-related group (DRG) and discharge disposition. Laboratory data are
available since 1986, and specify, in both inpatient and outpatient settings,
the test ordered, the date ordered, specimen source, results and date of the
results. All radiographic studies performed at GHC facilities, including MRI
and CT scans, are now available in the outpatient visits file. Beginning in the
early 1990s, diagnosis and procedure data were incorporated into the outpatient
registra-tion database, which also includes date of visit, the provider seen,
the provider’s specialty and the loca-tion of care.
As a longtime participant in the National Cancer Institute’s
SEER (Cancer Surveillance, Epidemiology and End Results) program, GHC receives
a data file of all newly diagnosed cancers among its enrollees, including
anatomical site, stage of diagnosis and vital status at follow-up. This file
covers a reporting area of 13 contiguous counties of northwest Washing-ton
State, and is maintained by the Fred Hutchinson Cancer Research Center in
Seattle, one of the 13 SEER population-based registries in the United States
(see http://seer.cancer.gov/AboutSEER.html).
GHC
has developed a death file that covers enrollees from 1977. Data are also
available from the Community Health Services department, from an immunization
database (see section on Vaccine Safety Datalink (VSD) later in this chapter),
and from claims databases for services purchased from non-GHC providers. Cost
information is available through the Utilization Management/Cost Management Infor-mation
System, developed in 1989.
Turnover
in membership at GHC is estimated to be approximately 15% per year (Saunders,
Davis and Stergachis, 2005). Since Group Health has been in existence for more
than 50 years, a subset of enrollees can be identified whose tenure spans
decades.
The
GHC databases have been widely used for phar-macoepidemiologic research
(Saunders, Davis and Stergachis, 2005), and GHC contributes to the HMO Research
Network (see section below). Limitations to the GHC databases include its small
size, a disad-vantage in the study of uncommon outcomes as most drugs are used
by only a small percentage of the population; the lack of information on some
important confounders, such as smoking and alcohol consump-tion; loss of drug
coverage for its Medicare enrollees; and limitations of the GHC formulary,
especially with regard to newly marketed drugs, since GHC may decide not to add
a new drug or may delay its adop-tion until it has been on the market for a
while. Drugs that offer little therapeutic or cost advantage over drugs already
listed on the formulary may be excluded. Non-formulary drugs as well as
over-the-counter drugs would be purchased for use outside the GHC pharmacy
system, and therefore would not be represented in the database.
Related Topics
TH 2019 - 2024 pharmacy180.com; Developed by Therithal info.