---
title: "Hemoglobin A1c With Reflex to 15-Anhydroglucitol (15-AG) Test: What It Measures & What Results Mean"
description: "It measures your 2–3 month average glucose (A1c) and, when needed, adds 15-AG to flag recent spikes—order through Vitals Vault at Quest."
canonical: "https://www.vitalsvault.com/biomarkers/hemoglobin-a1c-with-reflex-to-15-anhydroglucitol-15-ag"
last-updated: 2026-08-22
---

# Hemoglobin A1c With Reflex to 15-Anhydroglucitol (15-AG) Test: What It Measures & What Results Mean

> It measures your 2–3 month average glucose (A1c) and, when needed, adds 15-AG to flag recent spikes—order through Vitals Vault at Quest.

---

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