EPISODE

Conventions

Disease Episodes Episode of care: Describes anything related to the disease and spans all events related to a primary cancer diagnosis. Episode of care starts at day of the first recorded condition except unconfirmed rule out diagnosis. No end date is necessary for episode of care unless the patient dies. In that case, date of death will be the used as episode end date. Episode of care is the Parent Episode for the other Disease Episodes such as Disease Extent and Disease Dynamic and is always present. Use Disease Episode for episode_concept_id. For episode_object_concept_id, we recommend rolling up diagnosis information to the level of SNOMED that corresponds to ICD-10 categories.

Dynamic Episode A Disease Dynamic episode describes represents a period of time of consistent status of cancer. These should be either taken from the source or abstracted from the charts. We recommend the following convention and definitions for each Dynamic Episode: Disease Dynamic episode starts at day of Cancer Modifier indicating a material change in the disease status or Surgery. When the disease dynamic starts with surgery, the dynamic will be set to "remission", surgery report indicates otherwise. The episode_concept_id should be populated with a value from the Disease Dynamic Concept Class. Disease Dynamic episode ends at the start date of a new Disease Dynamic or Treatment Episode. If the Treatment Episode starts the same day as the Dynamic Episode, the Dynamic Disease episode is one day long. If the patient dies, date of death will be used as Dynamic Disease episode_end_date.

Extent Episode Disease Extent describes how far the cancer has spread. Similar to Disease Dynamic episodes, Extent episodes should be either taken from the source or abstracted from the charts. We recommend the following convention and definitions for each Dynamic Episode: Disease Extent episode starts at day of Cancer Modifier indicating a new disease extent:

1. Metastatic Extent starts at the first occurrence of a metastasis, distant lymph node or staging/grading Cancer Modifier indicating metastatic disease.
2. Invasive Extent starts at the first occurrence of invasion/extension, local lymph node or staging/grading Cancer Modifier indicating invasive disease.
3. Confined Extent starts at the first occurrence of Cancer Modifier that does not indicate the start of the other two extents. Disease Extent episode ends at the start of a different disease extent episode. If the patient dies, date of death will be used as Disease Extent Episode end date. The episode_concept_id should be populated with a value from the Disease Extent Concept Class.

Treatment Episode Treatment episode starts (i) at start of Drug Exposure, or (ii) at day of Procedure Occurrence and ends (i) at end of Drug Exposure, or (ii) at day of Procedure Occurrence. Conventions on how to populate episode_concept_id and episode_object_concept_id will be available soon.

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UNDER DEVELOPMENT

No.	Convention Description
1	Valid Episode Concepts belong to the 'Episode' domain.
2	Standard Episode Concepts are categorized by concept class: Disease Episode 32528 "Disease First Occurrence" 32529 "Disease Recurrence" 32530 "Disease Remission" 32677 "Disease Progression" Treatment Episode 32531 "Treatment Regimen" 32532 "Treatment Cycle" Episode of Care 32533 "Episode of Care"
3	The relationship between a disease episode and treatment episodes can be represented by the self-referencing foreign key column EPISODE.episode_parent_id.
4	A treatment EPISODE can be delivered at regular intervals, cycles or fractions. The parent-child relationship between a treatment episode and its constituent treatment cycles can be represented by the self-referencing foreign key column EPISODE.episode_parent_id.
5	Some episodes may not have links to any underlying clinical events. For such episodes, the EPISODE_EVENT table is not populated.