In the Group resource, the characteristics property is represented by code and valueCodeableConcept | valueBoolean | valueQuantity | valueRange.
How is valueRange represented in string?
For example, code + valueQuantity would be something like http://loinc.org|2823-3$gt5.4|http://unitsofmeasure.org|mmol/L. How would the range be represented in this case? Would it be a single number and that number is checked against the range represented by the valueRange since it has lower and upper range?
For example, if the characteristics contains code = system|code, and valueRange of 1.0 to 2.0, then ?characteristic-value=system|code$1.5 should match but ?characteristic-value=system|code$lt0.5 should not match. Is my assumption correct?
I think in general, the composite search parameters could use some more examples to illustrate how it should be parsed and used.