514 Subfield $c - Attribute accuracy explanation:

Subfield $c contains a definition of the thematic accuracy measure.

Example:

514 ##$bEstimated to be 98.5%.$cVillage names compared to source map -- all match, therefore errors are possible only if source maps are incorrect.$dNode-to-line, line-to-area topological relationships maintained. Line and area attributes maintained. GRASS 4.0 program "v.support" checks topological relationships.$eAll incorporated limits shown on USGS quads were digitized.$fThe accuracy of this data is based upon the use of the source maps ... [subfield $f shortened in this example]