Back

Version 2 of the pathology import of data into i2b2 is based on the mapping of the top 100 Blood Sciences and Microbiology tests ordered from GGH Cardio Locations. The test have been mapped to ​Snomed CT codes and ​LOINC codes to see which best serves our requirements.

The current working copy of the mappings is attached to this page. It is currently be reviewed by Paul Smalley.

Snomed CT Mapping

The Snomed CT mapping was carried out using the ​Snoflake and ​NPEx Snomed search engines.

It was not always possible to find Snomed CT codes for the exact finding associated with the test. In these instances a code for the procedure was used if one was available. At times Snomed CT had codes for specific findings (for example, a high, low, normal or abnormal level), but not a code for the more general finding.

LOINC Mapping

The LOINC mapping was carried out using the ​Search Loinc and ​HIPAA Space LOINC search engines.

LOINC has a lot more codes for the tests required and seems to provide a better match for the codes from the iLab system. LOINC provides multiple codes for each test depending on the sample analysed (blood, or serum or plasma) and the units used (mass/volume, moles/volume, count/volume, etc). The units for each test are recorded in iLab and so a match could be made. Where available, both sample type codes were recorded so that Paul Smalley could be given a choice when he checked the results.

Phase One (In Test)

In phase one Richard Bramley and Paul Smalley mapped 68 codes out of the top 100 tests requested by GGH Cario Locations. The tests that were not mapped were either administration codes (e.g., 'Add Another Test'), codes that represented a common group of other tests, or microbiology tests.

Phase Two (In Development)

The remainder of the codes commonly requested by GGH Cardio Locations - 407 codes in total, including those already mapped and admin codes. This time Paul and Richard are to be joined by Simon Hewson, who will be better able to map microbiology tests.

Phase Three... (In Planning)

Map the remaining tests from the pathology system.

There are 6 potential test results tables in the DWPATH data warehouse database.

Table	Number of Tests Types	Test Type Column
HAEM_TESTS	1589	Test_Code_Key
MICRO_TESTS	318	Test_Code_Key
BIOCHEM_TESTS	0	Test_Code_Key
CLINIC_TESTS	0	Test_Code_Key
MICRO_ORGANISM_TESTS	see below
TRANS_PROFILE_TESTS	99	Test_Code_Key
HISTO_STAINS	481	Stain_Code_Key

Microbiology

The MICRO_ORGANISM_TESTS table is a bit different to the rest (If it is a test result table at all). It has two candidate test type columns: MICRO_ORGANISM and MICRO_ORGANISM_TESTS. The second being the first one with a suffix. The number of test types using the different candidate codes is:

Table	Number of Tests Types	Test Type Column
MICRO_ORGANISM_TESTS	246855	Test_Code_Key
MICRO_ORGANISM_TESTS	441453	MICRO_ORGANISM_TESTS

This cannot be correct. The MICRO_ORGANISM_TESTS column is unique. I need to understand what this table represents.

Histology

I do not understand the Histology tables. I have taken a guess that the HISTO_STAINS is the table most similar to test results. However, I think it is probably more complicated than this.