Laboratory safety monitoring of chronic medications in ambulatory care settings.
OBJECTIVE
To evaluate laboratory safety monitoring in patients taking selected chronic prescription drugs.


METHODS
Retrospective study using 1999-2001 claims data to calculate rates of missed laboratory tests (potential laboratory monitoring errors). Eleven drugs/drug groups and 64 laboratory tests were evaluated.


METHODS
Two staff/network model health maintenance organizations.


METHODS
Continuously enrolled health plan members age> or =19 years taking > or =1 chronic medications.


RESULTS
Among patients taking chronic medications (N=29,823 in 1999, N=32,423 in 2000, and N=36,811 in 2001), 47.1% in 1999, 45.0% in 2000, and 44.0% in 2001 did not receive > or =1 test recommended for safety monitoring. Taking into account that patients were sometimes missing more than 1 test for a given drug and that patients were frequently taking multiple drugs, the rate of all potential laboratory monitoring errors was 849/1,000 patients/year in 1999, 810/1,000 patients/year in 2000, and 797/1,000 patients/year in 2001. Rates of potential laboratory monitoring errors varied considerably across individual drugs and laboratory tests.


CONCLUSIONS
Lapses in laboratory monitoring of patients taking selected chronic medications were common. Further research is needed to determine whether, and to what extent, this failure to monitor patients is associated with adverse clinical outcomes.
Hurley
Judith S
JS
Center for Pharmacoeconomic and Outcomes Research, Lovelace Respiratory Research Institute, Albuquerque, NM 87108, USA.
Roberts
Melissa
M
Solberg
Leif I
LI
Gunter
Margaret J
MJ
Nelson
Winnie W
WW
Young
Linda
L
Frost
Floyd J
FJ
D000553:Ambulatory Care / Q000592:standards*; D019411:Clinical Laboratory Techniques; D016903:Drug Monitoring / Q000592:standards / Q000706:statistics & numerical data*; D004358:Drug Therapy; D005260:Female; D006279:Health Maintenance Organizations; D006801:Humans; D008297:Male; D008508:Medication Errors / Q000706:statistics & numerical data; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D012449:Safety