Percentage-diabetes-glycated-hemoglobin-HbA1C-tests

INDICATOR NAME

Name

Percentage of patients with diabetes up-to-date with glycated hemoglobin (HbA1C) tests

Alternate Name

Percentage of patients with diabetes up-to-date with glycated hemoglobin (HbA1C) tests

INDICATOR DESCRIPTION

Description

Percentage of diabetic patients aged 40 years and older who have had two or more glycated hemoglobin (HbA1C) tests within the past 12 months

Indicator Status

Active

HQO Reporting tool/product

Personalized/Custom Reports (includes Practice Reports)

Dimension

Effective

Type

Process

DEFINITION AND SOURCE INFORMATION

Unit of Measurement

Percentage

Calculation Methods

Numerator/ Denominator * 100

Numerator including inclusion/exclusion

Number of diabetic patients aged 40 years and older who have had two or more glycated hemoglobin (HbA1C) tests within the past 12 months Includes: Ontario residents aged 40 years and older who are identified in the ODD as diabetics in the previous two years HbA1C tests are defined by the OHIP fee code (L093)

Denominator including inclusion/exclusion

Total number of diabetes patients aged 40 years or over Excludes: Patients who were not residents in Ontario in each year Patients with a missing or invalid HCN, date of birth or postal code Age on index date in each corresponding year exams: under 40 years Women with gestational diabetes

Adjustment (risk, age/sex standardization)- detailed

Data Source

Discharge Abstract Database (DAD), Ontario Diabetes Database (ODD), Ontario Drug Benefit (ODB), Ontario Health Insurance Plan (OHIP) Claims History Database, Registered Persons Database (RPDB)

Data provided to HQO by

Institute for Clinical Evaluative Sciences (ICES)

OTHER RELEVANT INFORMATION

Caveats and Limitations

The ODD does not differentiate between type I and type II diabetes mellitus. HbA1c measure only includes OHIP fee for service hemoglobin A1c tests conducted in community labs. Lab tests for A1c conducted in hospitals are not individually submitted and therefore not available.

Comments Detailed

Further information on the methodology used to generate a diabetes chronic disease cohort from which diabetic patients in this measure are drawn: The algorithm to identify patients with diabetes links different databases at ICES and is based on having two physician claims with a diagnostic code for diabetes (Dx Code 250) or one OHIP fee code for diabetes management, insulin therapy support, diabetic management assessment codes claim (Q040, K029, K030, K045, K046) or one hospitalisation with a diagnostic code of diabetes within 2 years. Gestational diabetes is excluded from this definition based on the following algorithm: Whenever there was a hospital record with a diagnosis of pregnancy care or delivery between 120 days before and 180 days after a gestational admission date, the diabetic record was considered to be for gestational diabetes, and it was excluded. The administrative data case-definition algorithm for diabetes has a sensitivity of 86% and specificity of 97%.5.

Footnotes

5 Hux JE, Ivis F, Flintoft V, Bica A. Diabetes in Ontario: determination of prevalence and incidence using a validated administrative data algorithm. Diabetes Care 2002; 25:512-516