LOINCActiveBoth

LOINC Code 4478-4: Complement C1q [Mass/Vol]

4478-4 is a LOINC code used to identify Complement C1q [Mass/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 Complement C1q. It is commonly used with the system or sample type Ser/Plas.

Reviewed by HealthAssure Clinical TeamUpdated 25 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 Complement C1q. It is commonly used with the system or sample type Ser/Plas.

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

What it does not mean

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

Key facts

  • Complement C1q [Mass/volume] in Serum or Plasma
  • Complement C1q
  • Comp; Complement c1q binding; Complmt; HEMATOLOGY/CELL COUNTS; Level; Mass concentration; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR

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

Complement C1q [Mass/Vol]Complement C1q [Mass/volume] in Serum or PlasmaC1q SerPl-mCncComplement C1qHEM/BCComplement C1q, BloodMCnc

Frequently asked questions

Code details

Code4478-4
SystemLOINC
Display nameComplement C1q [Mass/Vol]
DescriptionComplement C1q
Short nameC1q SerPl-mCnc
ComponentComplement C1q
PropertyMCnc
TimingPt
System (specimen)Ser/Plas
ScaleQn
ClassHEM/BC
Example unitsug/mL;mg/dL
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

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

Consumer names

Complement C1q, Blood

Part names

Complement C1qMCncPtSer/PlasQnMass ConcentrationPoint in time (spot)Serum or Plasma

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 4478-4 | HealthAssure