Exposure episode construction
Exposure records → episode rules → episodes → switching, gaps and discontinuation
Flow diagram
Steps
Exposure source records
Specify prescriptions, dispensing or administration sources and dates.
Standardize and deduplicate exposure
Resolve duplicate records, units and incompatible dates.
Define episode construction rules
Specify days supply, overlaps, stockpiling, washout and grace periods.
Construct exposure episodes
Create episode identifiers while preserving person identifiers.
Classify switching, gaps and discontinuation
Specify how concurrent and sequential exposures change episodes.
Validate episodes and person-time
Check implausible durations and assess alternative construction rules.
Tables and supporting information
Episode rule specification
People, records and episodes are different units; do not reconcile them by summation.
Validation evidence
Record validation sample, algorithm version and findings.