Existing Wording: This allows for simple combinations of and/or values, but doesn't allow a search based on a pair of values, such as all observations with a sodium value >150 mmol/L (particularly as the end criteria of a chained search), or searching on Group.characteristic: you need find a combination of key/value, not an intersection of separate matches on key and value. Another example is spatial coordinates when doing geographical searches.

Proposed Wording: N/A

Comment:

Please add an example.