DOYLC

The concept of null in HL7v3 is very different from HL7V2.x (See my old post on Null values in HL7V2.x. http://healthcareinformatics3000feet.blogspot.com/2007/11/null-values-in-hl7v2x.html ). This is essentially to do with lack of support for optionality in HL7V3 – Reference Information Model which itself rose from the issues associated with optionality in HL7V2.x – see else where in this blog for strengths and weaknesses of HL7V2.x and HL7V3.0. At a high level we can say that in HL7V3 the multiple exceptional values, i.e. values other than recommended or allowed by message specifications are grouped under the banner of NullFlavor. nullFlavor is a property of every data type through ‘extension.’ This property is valued and communicated as part of a message when information is missing. The flavor provides the reason why the information is missing. This can be best illustrated by the following example The Character String with Code ( SC ) data type contains a character string that optio...