Over the last decade, interoperability of the Electronic Health Record (EHR) is becoming more of a reality. However, inconsistencies in documentation such as pain are considered a barrier to obtaining this goal. In order to be able to remedy this issue, it is necessary to validate reference models that have been created based upon requirements defined by Health Level 7 (HL7), Logical Names and Codes (LOINC) and the Intermountain Clinical Element Model using external published sources and guidelines. Using pain as an example of complex and inconsistent documentation, it was found that the reference model based upon these standards is valid because the data elements identified are broad and can meet the needs of each sub-domain within the primary domain of pain.