The Notifiable Condition Mapping Table “Value Set” and its Role in

Case Reporting

Shaun Grannis, MD, MS FAAFPThe Regenstrief Institute and Indiana University School of Medicine

What we’ll coverThe central theme of this presentation is to establish:• Value sets (e.g., NCMT) are necessary for operationalizing HIT use

cases (case reporting);• Value set content will diverge and decay when active efforts to

synchronize are lacking;• When value sets diverge or decay, information supplied by/to the

intended use case is incomplete or inaccurate;• Feasible informatics solutions and stakeholder coordination can

mitigate value-set divergence,

Leading to the conclusion:Stakeholders with interest in particular HIT use cases must develop strategies to maintain needed value sets.

The Real-World Motivation for this Presentation

Premises• To optimally manage the public health

disease burden in a community, the true public health disease burden of a community must be ascertained

• Determining disease burden is strongly dependent upon information generated in clinical care processes

• However …

Challenges• Information generated in clinical care is highly variable

and often incomplete– Variations differ across organizations– Variations differ across time within organizations

• Far less than half of physicians have a fully functional EHR system

• Clinical care processes under-report to public health (Thacker)– Reporters overburdened/under-resourced– Reporters lack knowledge, willingness– Clinical data is scattered across disparate settings

• Reporting requirements vary over time and geography

The Strategy• Leverage (re-use) existing clinical data flows

to augment public health reporting• Minimize the need for human intervention in

the reporting process by …• Standardizing (to the extent possible in a

sustainable fashion) the heterogeneous data so computers can automatically inspect

A Strategic Consideration

• Who identifies whether a clinical case is reportable?

Notifiable Condition Detection

InboundMessag

es

Reportable

Conditions

Reportable

Results

ReportableResults

Database

Abnormal flag,Organism name in Dwyer II, Value above threshold

Compare to Dwyer I

Record Countas denominator

E-mailSummar

yRealtime Daily Batch

PrintReport

s

To PublicHealth

To InfectionControl

Monitoring Dashboard

Managing Data Sources

Condition

Test Codes

Notes About Test Codes and Conditions

• Some test codes are specific for a single disease, whereas others are less specific, e.g.:– 14470-9 is an EIA test code solely for Chlamydia trachomatis – 11475-1 is a general test code for "microorganism identified”

• The LOINC-to-Condition mappings improves the case detection processing efficiency in at least two ways. – Accuracy of the case detection methods can be improved by focusing

and tailoring the logic to the disease(s) expected to be found for a given test.

– Processing efficiency can be improved by scanning only potentially reportable transactions by assuming that a clinical transaction is potentially reportable when the transaction contains a known

notifiable LOINC code.

Value Sets

What is a Value Set?A “value set” is a collection of concepts

drawn from one or more terminology systems and grouped together for a specific purpose.

It may be a simple list of concepts drawn from a single code system, or it may contain expressions drawn from multiple code systems.

Sample Notifiable Conditions

Why This Value Set: Another Strategic consideration

• We cannot immediately change existing processes -- we can’t “boil the ocean” -- we must proceed incrementally

• When proceeding incrementally, we must prioritize activities

• Prioritization must incorporate a notion of the greatest value per unit of effort -- the “low-hanging fruit” methodology

• The NCMT represents such a low-hanging fruit

Comparison of NCMT’s

4,871

5,645

RG

CDC

3,691

3,498

Total Records Unique LOINC’s

923

730

2,768

4,421 Total UniqueLOINC’s

Two Approaches to Finding Additional Reportable Tests

• LOINC Axes• String similarity

LOINC Axes• LOINC codes are characterized according to a

number or properties, including:• Component: What is measured, evaluated,

or observed (Rotavirus Ag, Reagin Ab, etc.) • System: Context or specimen type within

which the observation was made (Serum, Urine, Blood, etc.)

• Method: Procedure used to make the measurement or observation (EIA, IF, Probe, etc)

LOINC Axes Results: New Reportables

97272 410

Using LOINC axes of Component, System, and Method the Regenstrief (RG) NMCT identified 272 novel reportable LOINC codes, the CDC NCMT identified 97 novel codes, and both identified 410 shared codes.

RG CDC

We cross-referenced the 682 newly identified Regenstrief potentially reportable LOINC codes with the INPC dictionary and found that 136 of the 682 are actively used in the INPC. Similarly we found that 29 of the 507 newly identified CDC codes are actively used in the INPC.

LOINC Axes Results: An ExampleLOINC not in CDC NCMT

LOINC not in RG NCMT

String Similarity• Many string comparator measures• We hypothesize that tests having a LOINC

component name similar to the nationally notifiable disease name may increase the likelihood the test is reportable for that condition.

String Similarity (cont’d)

151 Notifiable Conditions

57,145 LOINC CodesX = 8,678,725

Comparisons

String Similarity Results• 147 comparisons produced nearness scores

equal to or greater than 0.80, that were not found by the LOINC Axes method

• 122 of these were manually identified as true reportable tests (PPV = 83%)

What we’ll coverThe central theme of this paper is to establish:• Value sets are necessary for operationalizing HIT use-cases;• Value set content will diverge and decay when active efforts to

synchronize are lacking;• When value sets diverge or decay, information supplied to the

intended use case is incomplete or inaccurate;• Feasible informatics solutions and stakeholder coordination can

mitigate value-set divergence,

Leading to our conclusion:

Stakeholders with interest in particular HIT use cases must colaboratively develop strategies to maintain needed value- sets.

Process to Maintain NCMT

• Recognize the value of the NCMT as an asset to the national public health interests

• Identify appropriate stakeholders (e.g., CDC, CSTE, Regenstrief, etc.)

• Confer accountability and authority to manage the maintenance process

• Develop and continuously refine the maintenance process

Strawman Process

1. Either a new NND list is produced, or a new LOINC version released

2. New candidate notifiable results are identified using pragmatic, manageable search strategies

3. SME’s identify those that are truly reportable4. The NCMT is updated and disseminated

Concluding Remarks• Strategy: Identify and maintain value sets

critical to healthcare use cases***

• Tactics: Develop strategies for monitoring updates/changes over time, establish collaborations necessary to do so.

• Operational: Identify authorized and accountable stakeholders

*** this applies to many health care use cases!!!

The Notifiable Condition Mapping Table “Value Set” and its Role in

Case Reporting

Shaun Grannis, MD, MS FAAFPThe Regenstrief Institute and Indiana University School of Medicine