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Unified Medical Language System® (UMLS®)

MRCXT Builder

MRHIER.RRF has replaced the file MRCXT, which is no longer created by default. You are strongly encouraged to replace uses of MRCXT with MRHIER. MRHIER.RRF provides compete hierarchical information in a computable form which is much more compact and customizable for your purposes. MRCXT information is incomplete yet can be massive, increasing the size of the full Metathesaurus by over 66 percent.

If you decide to use the MRCXT builder, carefully consider your selections — for example, some sources have very large numbers of siblings with little relatedness or many, many children. Creating a MRCXT file with a large number of siblings or children can take over 15 hours.

MRCXT Builder enables you to generate and customize MRCXT.RRF for your subsets from the information found in the MRHIER.RRF and MRCONSO.RRF files.

You must select a Metathesaurus RRF subset (previously created using MetamorphoSys) to use the MRCXT Builder.

Help is available on:
Opening MRCXT Builder
File menu
Locating a subset
MRCXT file options
Selecting sources
Error messages


Opening MRCXT Builder

To Open MRCCT Builder:

File Menu

file menu image

The File menu has one option, Exit. Use this option to close the program.

Locating a Subset

MRCXT Builder can only be used with an RRF subset. Use the Browse button to locate the directory where the RRF was saved.

locate a subset

MRCXT File Options

MRCXT builder file options

Build Siblings: Check this option to show sibling relationships in the MRCXT file.

Build Children: Check this option to show child relationships in the MRCXT file.

Use Versioned Source Abbreviations: Check this option to produce a file with versioned source abbreviations, for example, MSH2004, instead of versionless source abbreviations, for example, MSH.

Compute XC Flags: Check this option to compute the values for the XC field. Checking this option results in a "+" in the raw data row in the XC column for the MRCXT file when a concept has one or more child values in this context. Selecting this option will increase the amount of time required to build the MRCXT file.

Prepend UTF-8 BOM characters to MRCXT.RRF: Check this option to produce a file with UTF-8 BOM characters.

Limit Contexts to: Check this option and indicate a number in the text entry box to limit the contexts a single atom can have in the MRCXT file. Limiting and/or reducing the number of contexts creates a smaller file and reduces the time it takes to build the file.

Selecting Sources

select sources menu

Highlight sources to build contexts for by clicking on each source name. Hold down the control key and click to select more than one source. Selecting fewer sources will decrease the amount of time it takes to build the MRCXT file. Contexts can only be built for sources that are already present in the subset.

Error Messages

At this point no error messages have been reported for the MRCXT builder.

Last Reviewed: August 14, 2014