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Laboratory results are integral to providing quality patient care.  The premise of the Sex for Clinical Use (SfCU) concept is an industry path forward, however there must be alternative solutions in the interim.

US Realm laboratories are subject to the Clinical Laboratory Improvement Amendments of 1988 (CLIA).  "Sex" (singular) is required by CLIA to be included in a laboratory test request, per §493.1241(c)(3), even if there are multiple tests ordered §493.1241(c)(4).

(3) The sex and age or date of birth of the patient. 

(4) The test(s) to be performed.

Laboratories have used HL7 V2 for decades which supports a single value:  PID-8 'Sex' until V2.4 in 2000 HL7 relabeled to "Administrative Sex".

It would be a substantive change requiring significant development by laboratories to support SfCU at the order level.  This change is not backwardly compatible with prior versions of HL7 as it directly and materially affects the use of the HL7 Version 2 standard for laboratories.  ANSI 2022 Essential Requirements, Annex A: Definitions, Substantive Change: A substantive change in a proposed American National Standard is one that directly and materially affects the use of the standard. Examples of substantive changes are below: - "shall" to "should" or "should" to "shall"; - addition, deletion or revision of requirements, regardless of the number of changes; - addition of mandatory compliance with referenced standards