The search for shorter LOINC names LOINC committee meeting Regenstrief Institute 2017-06-07

Background This set of questions started because one laboratory used the LOINC component (typically representing the analyte ) to represent the whole test name, and alone, in some cases it made no sense at all –

Purpose of LOINC LOINC purpose is to provide a universal code for linking the “same” observation from different sources Universal codes needed to tie all of one kind of observation together regardless of producer Needed for decisions support, flowsheet and trend displays, and MU quality, Health Information Exchanges (HIEs) and research, across institutions (OMOP OHDSI) The Inclusion of LOINC names with the code in HL7 messages is crucial for debugging, finding mis-mappings, through human and other kinds of reviews One of our major funders requires that names be unique on principle.

Historically lab test names are notoriously non specific. We saw it in spades when trying to map labs from five hospital systems and 3-4 referral labs for Indiana’s HIE .. E.g: When asked whether “glycine” was a serum or urine test. One lab says –everyone knows it is always done on plasma The other says- everyone knows it is always done on Urine

Some background

Current LOINC practices for lab LOINC provides three different names: Formal name, long common name and short name Formal name --uses official and spelled out, names for all parts ,e.g “coagulation surface induced” for protime-- , latin biologic names for plant allergens. These tend to be unattractive and very long, Long common name , 256 char max Short name – less than 40 char- Remember LOINC uses different models or radiology terms and survey questions

Current LOINC naming practice Name includes analyte, property, timing, specimen (system), scale Some times includes Method, super system- e.g Fetus , BPU , and timing selection e,g., maximum, minimum in a time interval 9rarely relevant to lab , LOINC builds all names from the parts records which include fields for building long, and short part from which all LOINC names are constructed thereby assuring consistency To LOINC common names we apply automatic rules that remove content that is redundant, e.g no need to include both Qn and Mass concentration

Present average and max size of each type of LOINC lab name Name type Average Lenght Current max lenght Name of longest one Formal 46 177 37989-1 (Artemisia vulgaris+Betula verrucosa+Cat dander+ Cladosporium herbarum+Dermatophagoides pteronyssinus+Dog dander+ Phleum pratense+Secale cereale) Ab.IgE: PrThr:Pt: Ser:Ord:Multidisk   Long 58 197 82083-7 Mold Allergen Mix 2 (Alternaria alternata+ Aspergillus fumigatus+ Candida albicans+Cladosporium herbarum+Setomelanomma rostrate +Penicillium notatum) IgE Ab RAST class [Presence] in Serum by Multidisk Short 22 40 47827-1 Adenosyl homocysteine hydrolase RBC-cCnt

Background-Test name lengths observed in national lab systems Source Kind of name Max length seen Max allowed example ARUP Result 47 Antimicrobial Susceptibility - AFB/Mycobacteria Mayo 130 (example is 100) Human T-Cell Lymphotropic Virus Types I and II (HTLV-I/-II) Antibody Screen with Confirmation, Serum Quest Based on small sample -?order 75 Mycobacterium tuberculosis complex, Laboratories have more than one name with possibly different names for catalogue versus reporting

Tiger team/ad hoc WG proposal for short names Create new set of names “Long name” with length less than or equal to 36 char- Very Short name with length less than or equal to 12 characters The provided sample names for 2258 common LOIONC names. But had only 1583 unique proposed names ,implying 675 LOINC terms in this set were duplicates

Snippet of proposed long names compared to existing LOINC short names 1 ALT SerPl-cCnc Alanine aminotransferase (S/P) 2 Albumin Fld-mCnc Albumin (B Fl) 3 Albumin CSF-mCnc Albumin (CSF) 4 Albumin SerPl-mCnc Albumin (S/P) 5 Albumin SerPl Elph-mCnc 6 Albumin Ur Elph-mCnc Albumin (U) 7 Albumin/Glob SerPl Albumin/Globulin (S/P) 8 Albumin ?Tm MFr Ur Elph Albumin % (U) 9 Albumin 24h MFr Ur Elph Albumin % 24h (U) 10 Albumin MFr Ur Elph

Highlight issues The two red cells are examples of ambiguous names- one applying to a spot urine and the other to a timed urine whose time is reported in another field The yellow one highlights a more subtle issue. MFr means mass fraction and indicates that the value reports a proportion of this amount versus the total. The use of ELPH indicates that this is an electrophoresis, and is reporting the percent of albumen in the whole protein electrophoresis. The prosed term does not.

Major differences between tiger team proposal and current LOINC names Proposed names Shorter specimen abbreviation and always surround with (), shorter specimen names but () add to size. Little/no use of embedding synonyms in names– like Thyroxin(T4)- which is used in LOINC and big laboratories Asserts the denominator analyte in some cases but not others. LOINC almost always does Same name is applied to different LOINC terms so lots of ambiguous name Does not distinguish mass vs substance and ignores scale other distinctions Tends to avoid acronyms (ALT vs alanine aminotranferase) Is verbose in some cases ( Interpretation –spelled out, instead of interp) Deals with a small but important subset of current terms Same name used for more than one LOINC terms

What is it we are trying to fix Tiger /ad hoc team would like shorter names (max of 35 characters) Would also like simpler names. Some content is irksome- e.g. property, scale or more to some Would also like super short names < 12 characters But the bottom line goal of the Tiger Team is to have a 35 character name that all EMRs would use. Would/could those ever be accepted –given they have names, different opinions about verbosity and length.

Choices and Limits First have to clarify where the limit is and on what side of the sender –receiver interface. Is it that lab systems have name limits close of 35 characters If they do, that may not always be relevant because many (?most( systems pull LOINC names from an independent file - often the LOINC table- at the time of HL7 message generation, and there are no important limits to the length of the LOINC name in the message Is the limit on the receivers side? Maybe, but Kaiser has a 60 character limit and other systems have larger ones.

Constraints For safety and contractual reasons (major LOINC support insists on unique names) names can’t be ambiguous Has to be automatable (via tables) and apply to all terms We could probably fit the size limit for terms chosen by the working group, but not all. (Some huge names don’t have acronyms)

Potential approaches to get close to proposal and avoid ambiguous names via LOINC short name or a new name. Would want it to work for all (or vast majority ) of lab tests and apply automatically to make it maintainable Would have to use common acronyms consistently over spelled out E.g. 80629-9 could be expressed as 1,2,2-Trimethylpropyl methylphosphonate Versus TMPA The Ad hoc proposal includes some acronyms but switches to full name when possible. Consistent use of acronym would be better for sorting and space savings Are parentheses around specimen really needed (2 more characters)-

The irksome parts of LOINC Property – used to distinguish concentrations from rates (excretion per time) and mass measures from molar measures etc. Scale- e.g quantitative vs qualitative –etc. With appropriate (but strict) default rules think we could drop much of this– (later) Timing- e.g Pt vs 24H- already default to the spot “Pt” or point, but will have to distinguish selections (e.g Maximum, Average) over multiple values in the time range Do have to figure a way to distinguish mass versus molar – because units are reported so inconsistently. Suggest “_m” and “_S” some wher in the name

Potential approach to get close to the proposed, AND avoid ambiguity Assumed defaults E.g for chemistry would assume quantitate and concentration unless otherwise specified Distinguish ordinals by adding QL Distinguish various ratios by include denominator analyte in the name Distinguish nominals by appropriate modifier of the core name. eg Salmonella serotype Distinguish mass from substance tests of a given type bu adding “_m” vs “_s “ Assume analytes with “…ase” at the end are enzymes and add “_m” at the end when it is a mass (have to test that this will work). Always include the super system- e.g. fetus, BPU when applicable Haven’t worked through all of this yet-

We also know LOINC the common name can be improved (and shortened) Long common names are longer than they need to be For instance Acanthamoeba sp DNA [Presence] in Unspecified specimen by Probe and target amplification method Might better be expressed as Acanthamoeba sp DNA NAAT QL Don’t say specimen unspecified , say nothing about specimen when it is specified in another part of the message Use Ql to identify ordinals NAAT NAAT does not quite capture the semantics of the fatter existing name

Dealing with short length limits 35 characters is not enough in general. (60 would be more practical ) Don’t know where the 34 came from- sender or receiver limits Many labs are not so limited Medical record systems can usually can take bigger names. Kaiser permanente’s limit is 60 characters and close to 25% of their names are greater than 25 Might be safety problems with35 as the target Questions to answer How often do laboratories pull form a copy of the LOINC table( think many do) verus using a field with a limited size in their own master fields What limits on result test names existing medical record system Conceivable that screen and/or paper report format constrain. But… wrapping in grids (e.g. HTML) is easy as pie. So reporting should not be a barrier. Lobby vendors to commit to some agreed on larger name size limit