Test names play a large role in determining the functionality for previous result values in Instrument Manager™ (IM). This article has some examples to help determine when test names should be unique versus identical.
Here’s the criteria by which previous results are considered to be related:
Previous results are derived by three criteria:
- The Patient ID: You might think this should be handled by the Specimen ID (SID), but if you draw blood on 2 separate days (2 separate SIDs) and run the same test, only Patient ID could effectively link them.
- Test Display Name: Why not code? If, for example, you have several instruments that perform the same test and they all use different codes, the previous results would not link due to the machine’s requirements. So, there is the ability through the luxury of test display name to allow this linkage to happen.
- The test must have been released. For example, if you have a test that is held for verification in Specimen Management Workspace, it is likely inherently suspect, so it will not factor into the previous results derivation until it is released, that is accepted by whoever releases it as valid.
1st Example: Patient had a Fasting Glucose test collected and tested today and had a 2 hour Post-Prandial (PP) collected and tested yesterday. The previous result field for the Fasting Glucose would be the result from the 2hr PP from yesterday if the Test Names were the same. If the test names were different, IM would look for a previous result from Test Name “Fasting Glucose.”
2nd Example: Patient has a Gentamycin Trough collected and tested today and had a Gentamycin Peak collected and tested two days ago. If all Gentamycin tests had the same Display Name of Gentamycin, the Gentamycin Peak result would be in the Previous Result Field.
Correct way to set up Test Names is to have a unique Test Name for each Test that is different.
The same thing could happen when having a different Fluid Type for the same test. If the test names were the same for the CSF Glucose and the Serum Glucose, looking back at previous results could erroneously populate with the wrong fluid Glucose result.
NOTE: If the test results can be the same for fluid Serum vs Plasma, then using the same Display Name would populate the Previous Result correctly.
PREVIOUS PATIENT RESULT 1-3 VS PREVIOUS RESULT VS PREVIOUS RUN RESULT
{Previous Patient Result 1-3}
Use this data element to evaluate the previous patient result on a patient for up to the most recent three released results prior to the current released result.
A result will be considered a previous patient result when the following conditions are met:
- Patient ID, Fluid Group, and Test Display Name data elements match between the results
- Test Status equals released
- Specimen ID and Request ID do not match between the results
NOTE: Fluid Group date element must be populated by rules. An example of using the Fluid Group data element is:
If: ( ( {Result} {On Any Test} {NOT} = “” ) {AND} ( {Fluid} {NOT} = “” ) )
Then: {Set} {Fluid Group} {On That Test} = {Fluid}
Else:
It is NOT recommended using the Fluid Group Data element unless there are tests that cannot have a Unique Test Display Name. The reason behind this is that a majority of chemistry tests can be run on either Serum or Plasma without causing an issue with Delta checks. You would need to identify those tests and combine them into one Fluid Group, instead of just setting the Fluid Group to equal Fluid. You would need several rules to accommodate the Serum/Plasma combination, Serum-only tests, Plasma-only tests, CSF-only tests, etc.
{Previous Result}
This data element can be used in a Rule to evaluate the previous result for a specified test. This data element could be populated in one of three ways:
- The value was returned from the instrument in results.
- The Laboratory Information System (LIS) sent this value in the order message.
- A released result value stored by the IM software in the Specimen Management database, indexed by Patient ID and the Test Display Name.
When there is more than one value present, the most recent previous result will be used. For example, when the LIS’ previous result and the value stored in the Specimen Management database have different date/times, IM compares the date/times and uses the most recent result.
{Previous Run Result 1-3}
Use this data element to evaluate the run result for the previous run for up to three previous runs prior to the current run. If a run includes two or more occurrences of a test, then the last test added for that run is used as ‘the’ test from that run. These Date Elements do NOT look at the Test Status for released, Held for Verification, etc.
This data element is used when comparing tests that are run in duplicate or rerun. Example would be for some Hepatitis tests that require if result is Reactive or Equivocal, to rerun in triplicate. This data element can also be used to determine if this result for this test on this specimen is being seen by IM for the first time: {Previous Run Result 01} = “” or IM has already seen a result for this test on this specimen: {Previous Run Result 01}{NOT}=””.
NOTE: IM uses Patient ID and Test Display Name in combination to identify the most recent previous result stored in its Specimen Management database. It is strongly recommended that a unique Test Display Name be created for any method whose previous results are used in rules. For example, it is critical that delta check rules only compare current results to previous results of the same fluid type, such as serum/plasma to serum/plasma or urine to urine. Accordingly, the Test Display Name should differ for serum/plasma and urine fluid types.
If you require assistance, check with your internal IT/IS department, or you may direct any questions or concerns related to this issue to your regional Data Innovations support team during their regular office hours. If you purchased IM from one of our business partners, please contact that business partner for support.
