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Introduction

In healthcare, there are many words with equivalent meanings. 

Gloss
tSynonyms
 provide alternative phrases referring to the 
Gloss
tconcept
. However, 
Gloss
tsynonyms
 are not created automatically for every possible combination of words with an equivalent meaning. The success of simple searches using one or more keyword depends on the text of the available 
Gloss
tdescriptionsWord Equivalent
Table  . Therefore searches will fail or will be incomplete where a different equivalent word is used in the search.

For example: "Kidney stone" and "Renal calculus" are synonymous 

Gloss
tdescriptions
 in 
Gloss
tSNOMED CT
. A search of 
Gloss
tSNOMED CT
 for the target phrase "kidney stone fragmentation" yields the result "Percutaneous nephrostomy with fragmentation of kidney stone," while a search for "Renal stone fragmentation" yields no results.

One way of addressing this problem is to maintain a table of 

Gloss
tword equivalents
. A table of this type is a prerequisite for exhaustive 
Gloss
tsynonym
 generation. 

Word Equivalents Starter Table

A

Gloss
tWord Equivalent
 starter table is included in the Lexical Resources archive file (note: this is not supported or maintained). It supports enhanced searches that take into account semantically similar words such as KIDNEY and RENAL. It also provides commonly used abbreviations. This table can be used by implementers to offer additional search capability in applications without greatly increasing the volume of
Gloss
tsynonyms
. It is not intended as a comprehensive dictionary of words. Many searches can be completed without using this table; like the other word search tables, it is completely optional and can be used as an example of a capability that may be customized and extended by
Gloss
tSNOMED CT
implementers.

Word Equivalents

...

Starter Table Structure

Key Fields


Specref
RefTypefield
tWordBlockNumber

A 32-bit

Specref
RefTypedata type
tInteger
shared by a set of equivalent words or phrases. The
Specref
RefTypefield
tWordBlockNumber
links together several rows that have an identical or similar meaning.

Specref
RefTypefield
tWordText

A word, phrase, acronym or abbreviation that is equivalent to the

Specref
RefTypefield
tWordText
of other rows that share the same WordBlockId.

Data Fields


Specref
RefTypefield
tWordType

An

Specref
RefTypedata type
tInteger
indicating the type of
Gloss
tequivalence

Specref
RefTypefield
tWordRole

An

Specref
RefTypedata type
tInteger
indicating the usual role of this word. This should be considered if attempting to find a
Gloss
tpostcoordinated
combination of
Gloss
tConcepts
that matches a phrase.

Example: Using word equivalents table to extend a failed search

A system user enters the search 

Specref
RefTypedata type
tString
 "Fragmentation of renal calculus;" the search returns no results. The search application that the user has been provided with has the option to extend the search by using the Word equivalents table. The user selects this option and searches again using the same search 
Specref
RefTypedata type
tString
 .

The relevant entries in the starter word equivalents table are shown in .

Specref
RefTypefield
tWordBlockNumber

Specref
RefTypefield
tWordText

Specref
RefTypefield
tWordType

1021

KIDNEY

2 ( word equivalent )

1021

RENAL

2 ( word equivalent )

4430

CALCULUS

2 ( word equivalent )

4430

CALCULI

1 (word form variant)

4430

STONE

2 ( word equivalent )

9870

RENAL STONE

4 (equivalent phrase)

9870

KIDNEY STONE

4 (equivalent phrase)

9870

KIDNEY CALCULUS

4 (equivalent phrase)

9870

RENAL CALCULUS

4 (equivalent phrase)

9870

NEPHROLITH

2 ( word equivalent )

The table is used to make substitutions in the search string to produce all possible unique search variants:

  • "Fragmentation of renal calculus"
  • "Fragmentation of renal stone"
  • "Fragmentation of kidney stone"
  • "Fragmentation of kidney calculus"
  • "Fragmentation of Nephrolith"
  • "Fragmentation of renal calculus"
  • "Fragmentation of renal calculi"
  • "Fragmentation of kidney calculi"

These 8 search string are used as the target phrase for keyword searches on the word pair index. Results from all 8 searches are combined, and duplicate 

Gloss
tconcepts
 are eliminated, giving the final list of search results.