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.

LOINCActive

LOINC Code 63924-5: What was the longest length of time you stopped smoking because you were trying to quit [PLCO]

Name: LOINC Code 63924-5: What was the longest length of time you stopped smoking because you were trying to quit [PLCO]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:43.947Z

63924-5 is a LOINC code used to identify What was the longest length of time you stopped smoking because you were trying to quit [PLCO] 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 What was the longest length of time you stopped smoking because you were trying to quit. It is commonly used with the system or sample type ^Patient.

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 What was the longest length of time you stopped smoking because you were trying to quit. It is commonly used with the system or sample type ^Patient.

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
Method: PLCO

What it does not mean

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

Key facts

What was the longest length of time you stopped smoking because you were trying to quit [PLCO]
What was the longest length of time you stopped smoking because you were trying to quit
Len; PhenX; Point in time; QNT; Quan; Quant; Quantitative; Quit smoking longest time; Random

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

What was the longest length of time you stopped smoking because you were trying to quit [PLCO]Quit smoking longest time PLCOWhat was the longest length of time you stopped smoking because you were trying to quitPHENXTimePt^Patient

Frequently asked questions

Code details

Code63924-5

SystemLOINC

Display nameWhat was the longest length of time you stopped smoking because you were trying to quit [PLCO]

DescriptionWhat was the longest length of time you stopped smoking because you were trying to quit

Short nameQuit smoking longest time PLCO

ComponentWhat was the longest length of time you stopped smoking because you were trying to quit

PropertyTime

TimingPt

System (specimen)^Patient

ScaleQn

MethodPLCO

ClassPHENX

Example unitsD, W, Mo, Y

StatusACTIVE

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.36

Last changed2.65

Part names

What was the longest length of time you stopped smoking because you were trying to quitTimePt^PatientQnPLCOTime (e.g. seconds)Point in time (spot)

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.