Fasting criteria for screening: test properties and agreement with glucose tolerance.
The objective of this study was to characterise test properties and agreement for fasting glucose cut-offs used for screening diabetes in Indigenous Australian communities, across a range of diabetes prevalence. The oral glucose tolerance test (OGTT) was administered to adult volunteers (n=3249) for community-based diabetes screening in isolated settlements (n=25). Two-hour post-load glucose concentration was the 'gold standard' against which test properties were characterised for fasting plasma glucose cut-offs at concentrations of > or = 7.0 mmol/l (ADA criterion) and > or = 7.8 mmol/l (WHO criterion). Test sensitivity (95% CI) was greater for the ADA (72.5%, 67.4-77.1%) versus the WHO criterion (61.5%, 56.1-66.6%). Specificity was high (>98%) using either criterion. The post-test likelihood of diabetes, given a population prevalence of 14.8%, was 89.1% using the ADA criterion, and 94.9% using the WHO criterion. The ADA criterion gave better agreement than did the WHO criterion for diabetes prevalence > or = 8.6%, and the probability of false results was lower using the ADA criterion, when diabetes prevalence was > or = 12.8%. According to the ADA criterion most individuals ascribed false negative results were aged > or = 35 years, overweight/obese, or had impaired fasting glucose. The fasting glucose criterion of 7.0 mmol/l was superior to 7.8 mmol/l in screening for diabetes.
Daniel
Mark
M
Department of Epidemiology, School of Public Health, The University of North Carolina at Chapel Hill, CB #7440, Rosenau Hall, Room 306, Chapel Hill, NC 27599-7440, USA. danielm@email.unc.edu
Rowley
Kevin G
KG
O'Dea
Kerin
K
D000293:Adolescent; D000328:Adult; D001315:Australia / Q000453:epidemiology; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D003920:Diabetes Mellitus / Q000175:diagnosis* / Q000453:epidemiology; D005215:Fasting; D005951:Glucose Tolerance Test / Q000379:methods*; D006801:Humans; D008403:Mass Screening / Q000379:methods; D012016:Reference Values; D015203:Reproducibility of Results; D044465:White People
D001786:Blood Glucose