Convert ICD-10 Code J42 to ICD-9

Source ICD-10 Code		Target ICD-9 Code
J42 Unspecified chronic bronchitis		491.9 Chronic bronchitis NOS

ICD-10 to ICD-9 crosswalk for code J42 - unspecified chronic bronchitis based on the most recent General Equivalence Mappings (GEMS) information.