E. Guadagnoli et al., Impact of underuse, overuse, and discretionary use on geographic variationin the use of coronary angiography after acute myocardial infarction, MED CARE, 39(5), 2001, pp. 446-458
Citations number
42
Categorie Soggetti
Public Health & Health Care Science","Health Care Sciences & Services
BACKGROUND. Geographic variation in the use of medical procedures has been
well documented. However, it is not known whether this variation is due to
differences in use when procedures are indicated, discretionary, or contrai
ndicated.
OBJECTIVES, TO examine whether use of coronary angiography after acute myoc
ardial infarction (AMI) according to appropriateness criteria varied across
geographic regions and whether underuse, overuse, or discretionary use acc
ounted for variation in overall use,
DESIGN. Retrospective cohort study using data from the Cooperative Cardiova
scular Project.
SETTING, Ninety-five hospital referral regions.
PATIENTS. There were 44,294 Medicare patients hospitalized with AMI during
1994 or 1995, classified according to appropriateness for angiography,
MAIN OUTCOME MEASURE. Variation in use of angiography, as measured by the d
ifference between high and low rates of use across regions.
RESULTS. Across regions, variation in the use of angiography was similar fo
r indications judged necessary; appropriate, but not necessary; or uncertai
n. Variation was lowest for indications judged unsuitable (difference betwe
en high rate and low rate across regions = 16.3%; 95% CI = 12.6%; 20.6%), T
he primary cause of variation in the overall rate of angiography was due to
use for indications judged appropriate, but not necessary or uncertain, Wh
en variation associated with these indications was accounted for, the diffe
rence between the resulting high and low overall rates was 10.8% (9.4%, 12.
4%). In contrast, variation in the overall rate remained high when underuse
in necessary situations or overuse in unsuitable situations was accounted
for.
CONCLUSIONS. Across regions, practice was more similar for patients categor
ized unsuitable for angiography than for patients with other indications. V
ariation in overall use of angiography appeared to be driven by utilization
for discretionary indications rather than by underuse or overuse. If equiv
alent rates across geographic areas are judged desirable, then greater effo
rt must be directed toward defining care for patients with discretionary in
dications.