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Formal vs. Informal Help Informal Formal


Todd Cochrane


In a situation when leading spaces are not part of an official standard and are not required for the data to be properly interpreted, is it in conformance with the standard for them to be included by the sender in an AN type data element? Background discussion: The definition of "String" according to the X12 documentation quoted in Appendix A of the X12N version 4010 Implementation Guides named in the federal HIPAA regulations currently in effect includes the statement that "The significant characters shall be left justified." followed by the sentence "Leading spaces, when they occur, are presumed to be significant characters." X12N/TG2's HIPAA Interpretation Portal in response to HIPAA Interpretation Request 374 (quoted below) states in part "We conclude that the intent of the wording of this section is that in most cases, leading spaces should not be included. Inclusion of leading spaces is a statement by the sender that the data in a String data element actually requires the leading spaces to be properly interpreted, and that such leading spaces are an official part of the data." The X12N response to HIR 374 appears to indicate that "when they occur" is referring to the occurrence of leading spaces in a data standard or as being necessary to distinguish two or more otherwise identical values. Others have interpreted the standard as leaving it entirely to the discretion of the sender whether or not to include leading spaces up to the maximum allowed by the data string length. (The latter interpretation would allow a sender to treat an AN data element as fixed length by padding with leading spaces to the left. In addition, this interpretation would imply that this sentence "The significant characters shall be left justified" can be interpreted as "The significant characters should be left justified.")


X12.6 clearly states that leading spaces are to be treated as significant. Significant characters are those that have meaning to the data value.


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X12.6, section says the following with respect to the String data type: "A string data element is a sequence of any characters from the basic or extended character sets and contains at least one non-space character. The significant characters shall be left justified. Leading spaces, when they occur, are presumed to be significant characters. The X12C Communication & Controls Subcommittee response for preparing this interpretation not as advice to the submitter of this Request for Interpretation the following observation: In the quoted standard above, the use of the phrase, "when they occur," means simply what it says: Leading space are considered to be significant when they occur as leading spaces. When they are not there, they are not significant. The sentence would have the same meaning if the phrase were removed.
Submission 1/1/2009
Status Date 1/1/2009
Status F - Final
Primary References
Document 6010