Table 1 Diagnostic and therapeutic (ICD-9-CM, ICD-10, and ATC) codes used in the current study for drawing records and fields from Healthcare Utilization databases

Schizophrenia

ICD-10 codes (Lombardy)

 Schizophrenia

F20.*

 Schizotypal disorder

F21.*

 Delusional disorders

F22.*

 Brief psychotic disorder

F23.*

 Shared psychotic disorder

F24.*

 Schizoaffective disorders

F25.*

 Other psychotic disorder not due to a substance or known physiological condition

F28.*

 Unspecified psychosis not due to a substance or known physiological condition

F29.*

Drugs

ATC codes

 Antipsychotic agents

N05A (excluded N05AN)