Professional and Linguistic Assessments Board (PLAB) Practice Exam

What is the range for an abnormal oral glucose tolerance test (OGTT)?

1. 3.5-6.5

2. 6.5-7.8

3. 7.8-11

4. 11-14

The correct answer is: 7.8-11

An abnormal oral glucose tolerance test (OGTT) is characterized by specific glucose levels measured after a patient ingests a glucose solution. The standard threshold for diagnosing impaired glucose tolerance or diabetes following the OGTT is set at 2 hours post-glucose ingestion. A reading between 7.8 mmol/L and 11.0 mmol/L indicates impaired glucose tolerance, while a measurement of 11.1 mmol/L or above suggests diabetes. Thus, the range of 7.8 to 11.0 mmol/L accurately reflects the parameters used to evaluate results from the OGTT, making it the correct choice. This distinction is critical in clinical practice, as it helps identify individuals at risk for developing type 2 diabetes and allows for timely interventions. The other ranges provided do not align with these diagnostic criteria used in glucose tolerance testing.