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.

LOINCActiveObservation

LOINC Code 33533-1: Platelet aggregation (PRP control) [Rel units/Vol]

Name: LOINC Code 33533-1: Platelet aggregation (PRP control) [Rel units/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:20.069Z

33533-1 is a LOINC code used to identify Platelet aggregation (PRP control) [Rel units/Vol] 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 Platelet aggregation. It is commonly used with the system or sample type PRP^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 Platelet aggregation. It is commonly used with the system or sample type PRP^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: ACTIVE
Order vs observation: Observation
Method: Aggregometry.ristocetin induced.low dose

What it does not mean

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

Key facts

Platelet aggregation in Control Platelet rich plasma by ristocetin induced Low dose
Platelet aggregation
Agg; Aggr; COAGULATION; Contrl; Hematology; Heme; Normal; PA; Pl; Platelet rich plasma; Platelets; Platelt; Plt; Point in time; QNT; Quan; Quant; Quantitative; Random; Rist lo dose; RlACnc; Thrombocyte; Thrombocytes

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

Platelet aggregation (PRP control) [Rel units/Vol]Platelet aggregation in Control Platelet rich plasma by ristocetin induced Low dosePA PRP Cont Rist lo dosePlatelet aggregationCOAGPlatelet Aggregation, control BloodRelACnc

Frequently asked questions

Code details

Code33533-1

SystemLOINC

Display namePlatelet aggregation (PRP control) [Rel units/Vol]

DescriptionPlatelet aggregation

Short namePA PRP Cont Rist lo dose

ComponentPlatelet aggregation

PropertyRelACnc

TimingPt

System (specimen)PRP^Control

ScaleQn

MethodAggregometry.ristocetin induced.low dose

ClassCOAG

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.09

Last changed2.82

Consumer names

Platelet Aggregation, control Blood

Part names

Platelet aggregationRelACncPtPRP^ControlQnAggregometry.ristocetin induced.low doseRelative Arbitrary ConcentrationPoint in time (spot)Platelet rich plasma^Controlristocetin induced Low dose

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.