In recent months I’ve had some discussions with Dan Vreeman at Regenstrief about the need to be able to group or aggregate “clinically equivalent” LOINC codes (however “clinically equivalent” is defined - mol and mass is one obvious case). The original impetus for our discussion isn’t being pursued on my end at the moment, but Dan did say that Regenstrief is embarking on an effort of their own to develop the capability for doing something like this. I am sure that they would be interested in hearing about use cases that are being identified that need this capability (and also about anyone with an interest in helping them with getting the work done).
Not only different countries. Within Australia different labs use different measuring equipment or different standards for measurements, for which there are different HL7 codes.
Thanks for the input. This is going to be a universal issue, however and wherever we are trying to aggregate bits of ‘clinically identical’ lab data as-per your example.
I am interested in how this is done now, as LOINC is not extensively used in the UK outside individual institutions, and my understanding is that the LOINC terminology carries enough relationship metadata to allow
2160-0 Creatinine [Mass/volume] in Serum or Plasma Creatinine Qn mg/dL
14682-9 Creatinine [Moles/volume] in Serum or Plasma Creatinine Qn umol/L
to be queried/inferenced as ‘Creatinine Serum or Plasma’ but this would require a LOINC-aware terminology server.
or do folk just manually document the sets of terms to be queried?
bit of both - there are some institutions running on a terminology server that can manage those kind of things, and others have to do manual conversion. But terminology servers are gradually becoming more commonly deployed (all the good ones I know of are free).
this is what the LOINC-SNOMED CT mapping intends to achieve. Below are the two SNOMED CT representations of the two LOINC codes:
2160-0 Creatinine [Mass/volume] in Serum or Plasma
‘Observable entity (observable entity)’
and (Component some ‘Creatinine (substance)’)
and (Scale some ‘Quantitative (qualifier value)’)
and (‘Time aspect’ some ‘Single point in time (qualifier value)’)
and (‘Property Type’ some ‘Mass concentration (property) (qualifier value)’)
and (‘Inheres In’ some ‘Plasma (substance)’)
and (‘Direct Site’ some ‘Acellular blood (serum or plasma) specimen (specimen)’)
14682-9 Creatinine [Moles/volume] in Serum or Plasma
‘Observable entity (observable entity)’
and (Component some ‘Creatinine (substance)’)
and (Scale some ‘Quantitative (qualifier value)’)
and (‘Time aspect’ some ‘Single point in time (qualifier value)’)
and (‘Property Type’ some ‘Substance concentration (property) (qualifier value)’)
and (‘Inheres In’ some ‘Plasma (substance)’)
and (‘Direct Site’ some ‘Acellular blood (serum or plasma) specimen (specimen)’)
This expressions (which could be queried for or added as a grouper SNOMED CT concept):
‘Observable entity (observable entity)’
and (Component some ‘Creatinine (substance)’)
and (Scale some ‘Quantitative (qualifier value)’)
and (‘Time aspect’ some ‘Single point in time (qualifier value)’)
and (‘Property Type’ some ‘Quantity concentration (property) (qualifier value)’)
and (‘Inheres In’ some ‘Plasma (substance)’)
and (‘Direct Site’ some ‘Acellular blood (serum or plasma) specimen (specimen)’)
I think it is fanciful to suggest that this could be done reliably by a system based purely on LOINC codes/definitions without recourse to manual construction of a list of codes or without knowing what constraints have been imposed on the sources of lab data.
By the way, there is already a LOINC code to cover tests that encompass either mass or molar concentrations of creatinine in serum or plasma:-
35203-9 Creatinine [Mass or Moles/volume] in Serum or Plasma ( see http://r.details.loinc.org/LOINC/35203-9.html?sections=Comprehensive ).
But despite the fact that its use for lab reporting is discouraged, its very existence almost guarantees that it will be used. The fact that this code is included in HEDIS panels and Value Sets suggest it might have been introduced into LOINC for downstream quality reporting.
A quick look through my LOINC tables shows the following potential codes that might need to be considered:-
"Creatinine [Mass or Moles/volume] in Serum or Plasma"
"Creatinine [Mass/volume] (Maximum value during study) in Serum or Plasma"
"Creatinine [Mass/volume] in Serum or Plasma --1 day post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --1 hour post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --1 hour pre XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --1.5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --1.5 hours pre XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --10 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --12 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --16 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --18 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --2 days post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --2 hour specimen"
"Creatinine [Mass/volume] in Serum or Plasma --2 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --2.25 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --2.5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --3 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --3.5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --3.75 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --30 minutes post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --30 minutes pre XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --4 days post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --4 hour specimen"
"Creatinine [Mass/volume] in Serum or Plasma --4 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --4.5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --45 minutes post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --45 minutes pre XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --5.25 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --5.5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --6 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --6.5 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --7 days post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --8 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --9 hours post XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --baseline"
"Creatinine [Mass/volume] in Serum or Plasma --post dialysis"
"Creatinine [Mass/volume] in Serum or Plasma --pre XXX challenge"
"Creatinine [Mass/volume] in Serum or Plasma --pre contrast"
"Creatinine [Mass/volume] in Serum or Plasma --pre dialysis"
"Creatinine [Mass/volume] in Serum or Plasma"
"Creatinine [Moles/volume] in Serum, Plasma or Blood"
"Creatinine [Moles/volume] in Serum or Plasma --1 day post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --1 hour post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --1 hour pre XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --1.5 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --1.5 hours pre XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --10 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --12 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --16 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --18 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --2 days post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --2 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --2.5 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --3 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --3.5 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --30 minutes post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --30 minutes pre XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --4 days post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --4 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --45 minutes post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --45 minutes pre XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --5 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --6 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --7 days post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --8 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --9 hours post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --baseline"
"Creatinine [Moles/volume] in Serum or Plasma --post XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --post dialysis"
"Creatinine [Moles/volume] in Serum or Plasma --pre XXX challenge"
"Creatinine [Moles/volume] in Serum or Plasma --pre dialysis"
"Creatinine [Moles/volume] in Serum or Plasma"
"Creatinine and Glomerular filtration rate.predicted panel - Serum or Plasma"
There are probably others.
regards,
eric
Eric Browne
eric.browne@montagesystems.com.au
ph 0414 925 845
skype: eric_browne
