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 66311-2: Date participant returned actigraph to clinic [PhenX]

Name: LOINC Code 66311-2: Date participant returned actigraph to clinic [PhenX]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:45.459Z

66311-2 is a LOINC code used to identify Date participant returned actigraph to clinic [PhenX] 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 Date participant returned actigraph to clinic. 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 Date participant returned actigraph to clinic. 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: TRIAL
Method: PhenX

What it does not mean

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

Key facts

Date participant returned actigraph to clinic [PhenX]
Date participant returned actigraph to clinic
Date AG returned; Point in time; QNT; Quan; Quant; Quantitative; Random; Returned AG

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

Date participant returned actigraph to clinic [PhenX]Date AG returned PhenXDate participant returned actigraph to clinicPHENXDatePt^Patient

Frequently asked questions

Code details

Code66311-2

SystemLOINC

Display nameDate participant returned actigraph to clinic [PhenX]

DescriptionDate participant returned actigraph to clinic

Short nameDate AG returned PhenX

ComponentDate participant returned actigraph to clinic

PropertyDate

TimingPt

System (specimen)^Patient

ScaleQn

MethodPhenX

ClassPHENX

Example unitsMMDDYY

StatusTRIAL

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.38

Last changed2.65

Part names

Date participant returned actigraph to clinicDatePt^PatientQnPhenXPoint 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.