IHTSDO-788 (artf6303) Crohn's disease: Review of the concept model

IHTSDO-788 (artf6303) Crohn's disease: Review of the concept model

 

 Source document – Combined inception-elaboration phase document v0.01 in Microsoft Word format

 

Content Improvement   Project

 

Combined Inception and Elaboration phases

Project   ID:     Artf6306 /IHTSDO-788      

Topic:    Crohn's disease: Review of the concept model

 

Date

August 3, 2016

Version

0.01

 

 

 

 https://projects.jira.snomed.org/browse/IHTSDO-788

 


Amendment History

Version

Date

Editor

Comments

0.01

2016070803

Geraldine Wade

Inception/elaboration of concept model and   organization of Crohn’s disease disorders with completion of preliminary   testing

 

 

 

 

 

Review Timetable

Review date

Responsible owner

Comments

 

 

 

 

 

 

 

 

 

© International Health Terminology Standards Development Organisation 2012. All rights reserved.

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1 Glossary

1.1 Domain Terms

Crohn’s   disease

Crohn's disease is an inflammatory bowel disease   (IBD). It causes inflammation of the lining of your digestive tract, which   can lead to abdominal pain, severe diarrhea, fatigue, weight loss and   malnutrition. Inflammation caused by Crohn's disease can involve different   areas of the digestive tract in different people.

http://www.mayoclinic.org/diseases-conditions/crohns-disease/basics/definition/con-20032061

Complications   due to Crohn’s disease

Obstruction: Crohn's disease can thicken the wall of   the intestine. Over time, the thickened areas of the intestine can narrow,   which can block the intestine. A partial or complete obstruction, also called   a bowel blockage, can block the movement of food or stool through the   intestines. A complete bowel obstruction is life threatening and requires   immediate medical attention and often surgery.

Fistulas: abnormal passages, or tunnels, between two   organs, or between an organ and the outside of the body. How a health care   provider treats fistulas depends on their type and severity. For some people,   fistulas heal with medication and diet changes, while other people will need   to have surgery.

Anal fissures: small tears in the anus that may cause   itching, pain, or bleeding. Most anal fissures heal with medical treatment,   including ointments, warm baths, and dietary changes

Ulcers: Inflammation anywhere along the GI tract can   lead to ulcers or open sores in a person's mouth, intestines, anus, and   perineum—the area between the anus and the sex organs. In most cases, the   treatment a health care provider prescribes for Crohn's disease will also   treat the ulcers

Malnutrition: a condition that develops when the body   does not get the right amount of vitamins, minerals, and nutrients it needs   to maintain healthy tissues and organ function. Some people may need IV   fluids or feeding tubes to replace lost nutrients and fluids.

Inflammation in other areas of the body   [Extra-intestinal manifestations]. The immune system can trigger inflammation in   the joints, eyes or skin.

https://www.niddk.nih.gov/health-information/health-topics/digestive-diseases/crohns-disease/Pages/facts.aspx

Extra-intestinal   manifestation of Crohn’s disease

Includes ocular [e.g. iritis], joint and skin   manifestations. These may present prior to the gastrointestinal   manifestations of Crohn’s.

Crohn's disease of skin

Cutaneous CD can also be divided into two   clinical forms: genital (56%) and extragenital (44%).

http://www.medicaljournals.se/acta/content/?doi=10.2340/00015555-0030

Crohn's disease of skin  can be either metastatic, contiguous or   reactive.

Metastatic Crohn's disease of skin

In rare instances (less than 100 cases reported   in the literature), cutaneous lesions are found in areas anatomically distant   from the gastrointestinal tract, separated by normal skin. This entity is   known as metastatic Crohn’s disease and comprises a high clinical variability   of cutaneous lesions including ulcers, papules, nodules, hard plaques and   crusts. It can affect any area of the skin, but the lower extremities, skin   folds and external genitals are the most commonly involved sites.

http://www.medicaljournals.se/acta/content/?doi=10.2340/00015555-0030

While metastatic Crohn’s of the skin is distant   from the GI site, other forms of skin involvement are contiguous lesions, which   are complications due to direct skin involvement from the gastrointestinal   disease, e.g., perianal, peristomal, and perifistular inflammations.

http://www.sciencedirect.com/science/article/pii/S2210836X1100025X

 

 

Crohn's disease of perianal skin

Perianal disease. You might have pain or drainage   near or around the anus due to inflammation from a tunnel into the skin   (fistula)

http://www.mayoclinic.org/diseases-conditions/crohns-disease/basics/definition/con-20032061

Perianal fistula due to Crohn’s disease

Perianal fistulas are a frequent manifestation of   Crohn's disease.

http://www.medscape.com/viewarticle/475289

They may cause pain or drainage near or around   the anus due to inflammation from a tunnel into the skin (fistula)

http://www.mayoclinic.org/diseases-conditions/crohns-disease/basics/definition/con-20032061

 

 

 

 

 

 

 

 

 

 

 

 

2 Introduction

2.1 Purpose

The purpose of this project is to review the concept model of Crohn’s Disease concepts and to recommend possible edits to these concepts.

 

SNOMED CT projects transition from Inception Phase à Elaboration Phase à Construction Phase à Transition Phase. This document combines the documentation of the Inception and Elaboration Phases.

 

The Inception Phase focuses on understanding the problem and its scope, identifying stakeholders and their requirements, and identifying risks.

 

The purpose of the Elaboration Phase is to develop, document and test one (or more) possible  technical solutions, and to reach a recommendation and provide a detailed specification of a preferred solution to be taken forward to the construction phase.

2.2 Audience and stakeholder domain

The audience for this document includes all standards terminology leaders, implementers and users but is especially targeted at those stakeholders from clinical practice who diagnose and treat patients with Crohn’s Disease. A further significant audience is the community of SNOMED authors that may be requested to implement the recommended specification.

2.2.1 Input from stakeholders

Specific input of stakeholders from original collabnet submission is not available. Input was based on collabnet submission in March of 2010.

 

2.2.2 Degree of consensus on the statement of problem

Consensus statements from the 2010 submission are not available; however, review of scientific literature with links as described in the concept definitions above provides consensus on Crohn’s disease and its manifestations. Additional clarity is provided by the application of a consistent concept model to each of the different types of Crohn’s disorders that can be categorized as digestive, extra-intestinal or as complications of the disease.

3 Statement of the problem or need

3.1 Summary of problem or need, as reported

The description of the problem includes an unresolved resolution of the concept model involving Crohn’s Disease concepts.  No baseline documents are available from the original collabnet description that is logged in March of 2010. The posted description notes that the project involved 25 Crohn’s disease concepts. At this time, as of the January 2016 release, there are 56 active Crohn’s Disease concepts (52 disorders, 2 situations, 1 qualifier value, 1 assessment scale). This project focuses on all Crohn’s disorders

 

3.2 Summary of requested solution

The requested solution is to review the concept model for the Crohn’s disease concepts, all of which are disorders, after inconsistencies were reported as the reason for the original submission.

 

3.3 Statement of problem as understood

The original submitter reported issues with inconsistencies in the concept model among the Crohn’s disease concepts, with acceptance by Kent Spackman in order to align with content with policy and to support the Problem List Use Case.

3.4 Detailed analysis of reported problem, including background

Analysis of the problem starts with a definition of Crohn’s Disease and its related concepts and a review of the concept model components.  Currently, there are 52 active Crohn’s concepts that are Disorders; there are 2 Crohn’s concepts that are Situations; there is one Crohn’s concept that is a Qualifier [Non-Crohn's] and one Crohn’s concept that is an Assessment scale. This review focuses on the 52 active Crohn’s concepts that are disorders and how they are organized and modeled. In subsequent sections of this document, there will be a description of inconsistencies noted in the concept models in terms of IS A, DUE TO and ASSOCIATED WITH relationships. Additionally, there are noted concepts that have incorrect placements within the node as well as the need to add 2 additional concepts to the current corpus.

 

3.5 Subsidiary and interrelated problems

Problems with the current concept model may result in issues with analysis and retrieval of data related to Crohn’s disease. There are a few noted concepts that are “non-Crohn’s” (e.g. “non-Crohn granulomatous colitis”) that do not impact this analysis.

4 Risks / Benefits

4.1.1 Risks of not addressing the problem

Problems with the current concept model may result in issues with analysis and retrieval of data related to Crohn’s disease based on the current logical definitions. There are also concepts with incorrect placement within the Crohn’s disease node and the need to clarify descriptions, namely perianal fistulas that burrow through to the skin versus Crohn's disease of perianal skin.

4.1.2 Risks of addressing the problem

There may be some risk to making concept model changes to those who have currently implemented SNOMED CT within their applications if relying on the description logic components but adding clarity and consistency to the various Crohn’s disease concepts should overall improve its implementation.

5 Requirements: criteria for success and completion

5.1 Criteria for success/completion

Analysis of all Crohn’s Disease concepts (n = 52) including their placement within the disorder hierarchy and review of concept model for each concept.

 

5.2 Strategic and/or specific operational use cases

The operational Use Case for this project is alignment with the Problem List

 

6 Solution Development

6.1 Initial Design

6.1.1 Outline of initial design

a. Breakdown of Crohn’s Disease concepts: There are 52 active Crohn’s concepts that are Disorders; there are 2 Crohn’s concepts that are Situations; there is one Crohn’s concept that is a Qualifier [Non-Crohn's] and one Crohn’s concept that is an Assessment scale

b. Organization of Crohn’s Disease concepts: Attention is focused on the 52 Crohn’s disease concepts that are Disorders. They can be organized and analyzed in three general groupings with attention to their attribute relationships: Crohn’s affecting a specific digestive site, Crohn’s affecting extra-intestinal sites and complications of Crohn’s disease.

c. Communication of recommendations are listed in a spreadsheet embedded within this document.

 

6.1.2 Significant design or implementation decisions / compromises

Recommendation was made to add 2 concepts as well as edits to some of the existing concepts in order that the concept model be consistently applied to the 3 general groupings.

6.1.3 Evaluation of Design

The redesign and restructuring of the Crohn’s disease concepts was tested completely through construction using the January 2016 version of SNOMED CT within a workbench/classifier. This validation should enable ease of revisions into the next SNOMED CT release

6.1.3.1 Exceptions and Problems

As noted within the design, the addition of 2 concepts is recommended.

6.1.3.2 Design Strengths

The design demonstrates consistency of the concept models as applied to Crohn’s affected sites (digestive versus extra-intestinal) as well as the complications of Crohn’s disease (e.g. fistulas, strictures, etc.)

6.1.3.3 Design Weakness

Not all possible manifestations of Crohn’s disease are included as described in the scientific review of possibilities. As the original submission documentation is not available, there are no known specific requests or input from stakeholders other than concept model inconsistencies among the Crohn disease concepts.

6.1.3.4 Design Risks

Description of risk

Importance

Mitigation plan

Concurrent authoring   changes may impact current review as authoring is ongoing

Minimal

Author review of tested   concepts as outlined is ready for construction.

 

 

 

7 Recommendation

7.1.1 Detailed design final specification

The major design elements are a restructuring of the Crohn’s disease concepts and the application of a consistent concept model to each of the Crohn’s disease divisions. For example, currently there are different models applied to some of the complications of Crohn’s disease. “Crohn's stricture of colon” IS A “Crohn’s Disease”, but “fistula of small intestine due to Crohn's disease” is DUE TO “Crohn’s Disease”.  Another example is “Crohn's disease of penis” is ASSOCIATED WITH “Crohn’s Disease” and “Crohn disease of scrotum” IS A “Crohn’s disease of skin”; they are both subtypes of “Crohn’s disease of skin”. Additional analysis shows a void is organization and the need for adding a concept “Extra-intestinal manifestation of Crohn’s disease (disorder)” as these are part of the disease process external to the digestive tract but are not considered to be complications (as in the definitions above). Another needed clarification is the concept “perianal Crohn disease” which can be a skin manifestation or more commonly, a perianal fistula that burrows into the skin. The design changes have been detailed in the included spreadsheet.

7.1.2 Iteration plan

The list of changes recommended for the Crohn’s concepts is detailed in the embedded spreadsheet. If done stepwise, there were no errors detected when using the test version of the workbench/classifier.

 

The overview of the resulting concepts in STATED VIEW is as follows:

 

Crohn’s disease in all of the digestive locations has parent IS A “Crohn’s disease”.

Extra-intestinal manifestations of Crohn’s disease (i.e. skin, joints, eyes) have parent "Extra-intestinal manifestation of Crohn’s disease" [new concept]

 

Complications of Crohn’s disease (i.e. stricture, fistula, hemorrhage, obstruction) have parent “complication due to Crohn's disease” [existing concept]. The existing concepts in this group that currently include “due to” in the description (e.g. intestinal obstruction due to Crohn’s disease) no longer need the DUE TO attribute in stated view and can be optionally removed as this meaning would be retained by the parent “complication due to Crohn's disease”.  A newer description in this group, e.g “Abscess of intestine co-occurrent and due to Crohn’s disease of small intestine” currently includes IS A and DUE with relationships to Crohn’s concepts and can be retained as these are intented to be explicit.

 

In the resulting revisions, all of the ASSOCIATED WITH “Crohn’s disease” have been removed.

Additional recommendations are made to clarify the meaning of the concept 235796008 | perianal Crohn's disease by altering its description to “Crohn's disease of perianal skin” in order to distinguish it from a more common “Perianal fistula due to Crohn’s disease” that is a complication and should be added as a new concept.

 

 

8 Quality program criteria

8.1 Quality metrics

8.1.1 Quality metric 1

Component

Characteristic and Description

Metric

Target

Result

Logic definitions of Crohn’s   disease concepts

Char:

sufficiently defined

-          Proportion sufficiently defined

-          Numerator: count of those defined.

-          Denominator: count of all concepts under “Crohn’s   disease” and under “complication of Crohn’s disease”

80%

 

In   the resulting 53 Crohn’s disease disorders, 8 will be primitive (85% defined   concepts)

Descr:

Concept logic definitions should be “defined” not   “primitive”

 

8.1.2 Quality metric 2

Component

Characteristic and Description

Metric

Target

Result

Completeness of content   in Crohns disease disorders

Char:

All Crohn’s disorders analyzed

-          Proportion meeting guidelines, based on manual   review

100%

100% of all existing Crohn’s concepts

Descr:

Additional concepts can be added based on more   extra-intestinal manifestations that are described in the literature but all   existing concepts have been addressed

 

 

8.2 Use case scenarios

All Crohn’s concepts (n = 53) were tested using a workbench/classifer.  Additional options for revisions are available if desired by the editors. One example would be to change the description of “Crohn’s stricture of colon” to “Stricture of colon co-occurrent and due to Crohn’s disease”. This pattern could be applied to other concepts in this group of “complications of Crohn’s disease”.

 

8.3 Test cases

Same as previous paragraph

9 Project Resource Estimates

Project size:  Involves edits to 25 concepts and the addition of 2 new concepts

As depicted in the spreadsheet, the suggested changes are catalogued and can be done sequentially as in the list. No risks were identified when tested using a classifer.

9.1 Scope of construction phase

The scope is well defined and completed list of concepts and changes are depicted in the spreadsheet

 

9.2 Projection of remaining overall project resource requirements

9.2.1 Expected project resource requirement category

Small – based on testing already done, the work should require no more than 4 hours of editing in the authoring tool.

9.2.2 Expected project impact and benefit

With the expected edits, Crohn’s disease concepts will be better organized and include a consistent concept model to its complications and extra-intestinal manifestations.

9.2.3 Indicative resource estimates for construction, transition and maintenance:

 

Construction and transition phase:         25 concepts to be edited; 2 new concepts to be authored

Maintenance phase:       2-3 new ‘frequent usage’ concept requests in 1st 3 years

 

 

Embedded spreadsheet with several tabs:

 

                       

 

Tested recommendations are under tab “List of changes”

 

Document below is a previous version that had been uploaded as a confluence page. Attached here for reference. 

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