What is DIAGNOSIS CODE?
DIAGNOSIS CODE meaning The first of these codes is the ICD-9-CM diagnosis code describing the principal diagnosis (i.e. The condition established after study to be chiefly responsible for causing this hospitalization). The remaining codes are the ICD-9-CM diagnosis codes corresponding to additional conditions that coexisted at the time of admission, or developed subsequently, and which had an effect on the treatment received or the length of stay.
reference: Centers for Medicare & Medicaid Services