HL7 Issues Facing Developers
By: Johnathon Wright on: January 24, 2013
h2. Inconsistent use of HL7 Value Types
Trying to increase quality control, I set told my import agent not to flag any observations where the value type wasn't what my app would have selected as the value type. The results were surprising.
|Field|Quest's Value Type|Quest's Value|LabCorp Value Type|LabCorp Value|Expected| |eGFR|ST|>60|ST|>59|NM| |Vitamin D2|TX|< 4|||NM| |BUN/Creatinine Ratio|TX|NOTE|||NM|
So I guess the moral of the story is that Inequalities aren't considered numeric by LabCorp or Quest. It might be ST or TX. And also ST and/or TX might be used for random other things like "Please see note."
h2. Storing notes in the value
Although I think it is overused, HL7 does provide a convenient note segment, NTE, that allows a lab to attach notes to an observation, patient, etc.
I received the following observation (OBX) from Access Labs:
value type: ST identifier: 127^CRP, Cardio^L value: 0.4 Low Risk of CVD units: mg/L+ (sic)
Seriously. WHAT IS GOING ON HERE?
OBX|59|ST|127^CRP, Cardio^L||0.8 Low Risk of CVD|mg/L+| |N||S|F||||||||||||ACCESS MEDICAL LABORATORIES|5151 CORPORATE WAY^^JUPITER^FL^334583101 NTE|1|L| Low Risk of Cardiovascular Disease: CRP < 1 mg/L NTE|2|L| Medium Risk(<2-fold increase) : CRP 1-3 mg/L