Coding

OASIS Diagnosis (M1021)

OASIS Item M1021 captures the patient's primary diagnosis and principal diagnoses that are actively addressed during the home health episode

Definition

OASIS Item M1021 captures the patient's primary diagnosis and principal diagnoses that are actively addressed during the home health episode

Why it matters

OASIS Diagnosis (M1021) is part of the Coding vocabulary used across home health operations, documentation, and revenue cycle. Understanding it helps clinicians, QA leads, and administrators stay aligned on care quality and compliance.

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