Need to eliminate substring matches

[cmungall]

With this admittedly silly query I get spurious matches with MEDIUM confidence

curl -L -s 'http://www.ebi.ac.uk/spot/zooma/v2/api/services/annotate?propertyValue=range+600-1K' | jq '.[] | .confidence, .semanticTags, .annotatedProperty.propertyValue'
"MEDIUM"
[
  "http://purl.obolibrary.org/obo/NCIT_C38013"
]
"Range"
"MEDIUM"
[
  "http://purl.obolibrary.org/obo/NCIT_C134240"
]
"Analytical Procedure Range"

the first matches a substring. The second is a match with one string in common.

Why are these MEDIUM and not LOW? Is there a way to eliminate substring or overlapping string matches?