---
title: "T4 Free Direct Dialysis Test: What It Measures"
description: "It measures your unbound free T4 using dialysis for accuracy, with clear ordering and results support through Vitals Vault and Quest labs."
canonical: "https://www.vitalsvault.com/biomarkers/t4-free-direct-dialysis"
last-updated: 2026-08-22
---

# T4 Free Direct Dialysis Test: What It Measures

> It measures your unbound free T4 using dialysis for accuracy, with clear ordering and results support through Vitals Vault and Quest labs.

---

Canonical HTML: https://www.vitalsvault.com/biomarkers/t4-free-direct-dialysis
- [llms.txt](https://www.vitalsvault.com/llms.txt)
- [sitemap.xml](https://www.vitalsvault.com/sitemap.xml)
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