What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINC

LOINC Code 16629-8: aPTT Coag (Bld control) [Time]

Name: LOINC Code 16629-8: aPTT Coag (Bld control) [Time]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T11:17:26.379Z

16629-8 is a LOINC code used to identify aPTT Coag (Bld control) [Time] 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 Coagulation surface induced. It is commonly used with the system or sample type Bld^Control.

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 Coagulation surface induced. It is commonly used with the system or sample type Bld^Control.

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: DEPRECATED
Method: Coag

What it does not mean

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

Key facts

Deprecated Activated partial thrombplastin time (aPTT) in Blood from control by Coagulation assay
Coagulation surface induced
Activated partial thromboplastin time; aPTT; Blood; Clot; Clottable; Coag; Coagulation assay; Contrl; Hematology; Heme; Little(A)PTT; Normal; Partial Thromboplastin Time; Point in time; PTT; QNT; Quan; Quant; Quantitative; Random; Surf; Tilt tube; WB; Whole blood

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

aPTT Coag (Bld control) [Time]Deprecated Activated partial thrombplastin time (aPTT) in Blood from control by Coagulation assayDeprecated aPTT Bld Cont QnCoagulation surface inducedCOAGaPTT, control BloodTime

Frequently asked questions

Code details

Code16629-8

SystemLOINC

Display nameaPTT Coag (Bld control) [Time]

DescriptionCoagulation surface induced

Short nameDeprecated aPTT Bld Cont Qn

ComponentCoagulation surface induced

PropertyTime

TimingPt

System (specimen)Bld^Control

ScaleQn

MethodCoag

ClassCOAG

StatusDEPRECATED

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0l

Last changed2.36

Consumer names

aPTT, control Blood

Part names

Coagulation surface inducedTimePtBld^controlQnCoagaPTTTime (e.g. seconds)Point in time (spot)Blood^ControlCoagulation assay

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.