A diabetes panel groups tests that describe glucose over different windows: HbA1c, fasting glucose, post-prandial glucose, and sometimes fasting insulin and HOMA-IR. Each line answers a different question, and HOMA-IR is calculated. This page explains what each test reflects, not whether your values are normal. The range printed on your report is the one that applies.
A diabetes panel is a group of metabolic tests rather than one measurement. The lines differ in the window of time they describe: one averages weeks, two record a moment, one measures insulin, and one is arithmetic.
What the panel measures
HbA1c reflects the share of haemoglobin that has glucose attached. Because red cells circulate for weeks, it describes average glucose exposure over the preceding weeks to months. It moves slowly.
Fasting glucose measures glucose after a period without food, usually overnight. Post-prandial glucose measures glucose at a recorded time after a meal. Both are snapshots, and the timing is part of the result.
Fasting insulin measures insulin, the hormone that moves glucose into tissues. It is not a glucose value, and it is read with the paired glucose. HOMA-IR is calculated from both fasting values using a published equation; it is a surrogate index, not a laboratory measurement, and it has no unit.
The tests inside it
| Test | Also printed as | Unit | What it reflects |
|---|---|---|---|
| HbA1c | A1c, glycated haemoglobin | percent (NGSP), mmol/mol (IFCC) | Average glucose exposure over the preceding weeks to months. |
| Fasting glucose | FBS, fasting blood sugar | mg/dL, mmol/L | Glucose at one moment after a period without food. |
| Post-prandial glucose | PPBS, PPG | mg/dL, mmol/L | Glucose at one moment, at a recorded time after a meal. |
| Fasting insulin | FINS, IRI | uIU/mL (mIU/L) | Insulin after fasting, the hormone that moves glucose into tissues. It is not a glucose value. |
| HOMA-IR | HOMA, HOMA-IR (calculated) | Unitless | A calculated index derived from fasting insulin and fasting glucose. |
Some reports also print an estimated average glucose derived from HbA1c. It is calculated, not a separate measurement, and it should move with the HbA1c it came from.
Why this page does not print a range
Reference ranges differ by laboratory, method, and clinical context. For HbA1c, some reports print a population range while others print a target taken from a guideline, and the two are not interchangeable. Fasting and post-prandial results also depend on sample timing.
The range or target printed on the report that produced your value is the one that applies. Doctano keeps that printed range or target with the result. It does not replace it with a general value from the internet, because a target that suits one person may not suit another.
What moves together
HbA1c is a longer average, while fasting and post-prandial glucose are single moments. That difference explains most disagreements between the lines. A high average with an unremarkable fasting sample, or the reverse, is possible, and neither line cancels the other.
Fasting insulin is not a glucose value. It measures the hormone that moves glucose into tissues, so it can be raised while glucose sits inside the printed range. That is why insulin is read with the paired glucose rather than alone.
HOMA-IR is calculated from both fasting values using a published equation; the HOMA-IR calculator sets out the version. Because it is built from two measurements, it inherits variation in either one, and a different equation can give a different number from the same inputs. The index is a surrogate marker, not a diagnosis.
HbA1c has its own moving parts. Conditions that change how long red blood cells survive, or that change haemoglobin itself, can move it in either direction. Some anaemias, recent blood loss or transfusion, pregnancy, and some haemoglobin variants are examples that depend on the assay.
How to read the report's own grouping
- Read the order. Many reports print HbA1c first, then fasting glucose, then post-prandial glucose, then insulin and a calculated index. Some group the glucose lines together instead.
- Find the flags. A flag means the laboratory compared the value with its printed range or target. It may be high, low, or a written comment, and it is not a diagnosis.
- Check which values are calculated. HOMA-IR and an estimated average glucose are derived lines. They are not independent measurements, and the report may print the equation or a note beside them.
- Check the unit. HbA1c appears as a percentage on one scale and as mmol/mol on another. Glucose appears as mg/dL or mmol/L. Insulin in uIU/mL and mIU/L is the same scale. HOMA-IR has no unit.
- Check the timing. Fasting values depend on how long the person went without food, and post-prandial values depend on the interval after the meal. HbA1c does not depend on fasting in the same way.
- Read the remarks. A method note, a comment about a haemoglobin variant, or a note about sample type can explain a result that looks out of place.
What a flagged result means, and what it does not
A flag means the value sits outside the range or target the laboratory printed. It does not diagnose a condition, and it does not say why the value is where it is. A clinician reads it with the person's history and the rest of the report.
A value inside the printed range is not proof that glucose is behaving. A fasting glucose inside the range does not describe what happens after a meal, and an HbA1c inside the range does not describe a single high reading. The trend and the other lines carry information a single flag does not.
The cross-year view
Compare the same test, in the same unit, from the same laboratory where possible. HbA1c as a percentage and as mmol/mol are different scales, and glucose in mg/dL and mmol/L is different too. A change of unit can look like a change in the result.
HbA1c moves slowly, so a change between two reports taken close together is smaller than the change across a longer interval. Fasting and post-prandial glucose are more variable from sample to sample.
Doctano keeps each result with its printed range and places it on the profile's timeline. Names and units are normalized across laboratories, so the same marker lines up across years, and every point still opens the report it came from.
What this page is not
This page explains the panel in general. It does not interpret your result, diagnose a condition, or recommend treatment or medicine changes. It is not medical advice. Verify the values and units against the original report, and discuss the result with a qualified professional.