LOINCActiveBoth

LOINC Code 4631-8: Hemoglobin F Apt-Downey method Ql (Stl)

4631-8 is a LOINC code used to identify Hemoglobin F Apt-Downey method Ql (Stl) in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Hemoglobin F. It is commonly used with the system or sample type Stool.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Hemoglobin F. It is commonly used with the system or sample type Stool.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Both
  • Method: Apt-Downey

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • Hemoglobin F [Presence] in Stool by Apt-Downey method
  • Hemoglobin F
  • Bowel movement; Faecal; Faeces; Fecal; Feces; Fetal hemoglobin; Haemoglobin; Hb; HbF; HEMATOLOGY/CELL COUNTS; Hgb; Hgb F; Ordinal; Point in time; PR; QL; Qual; Qualitative; Random; Screen; Stl; Stool = Fecal

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Hemoglobin F Apt-Downey method Ql (Stl)Hemoglobin F [Presence] in Stool by Apt-Downey methodHgb F Stl Ql Apt-DowneyHemoglobin FHEM/BCHemoglobin F, StoolPrThr

Frequently asked questions

Code details

Code4631-8
SystemLOINC
Display nameHemoglobin F Apt-Downey method Ql (Stl)
DescriptionHemoglobin F
Short nameHgb F Stl Ql Apt-Downey
ComponentHemoglobin F
PropertyPrThr
TimingPt
System (specimen)Stool
ScaleOrd
MethodApt-Downey
ClassHEM/BC
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0
Last changed2.73

Consumer names

Hemoglobin F, Stool

Part names

Hemoglobin FPrThrPtStoolOrdApt-DowneyPresence or ThresholdPoint in time (spot)Apt-Downey method

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

LOINC Code 4631-8 | HealthAssure