Self-controlled case and event selection
Identify cases and qualifying events
SCCS includes people who experienced an event. Check that event occurrence does not invalidate the exposure or observation process assumed by the chosen model. Keep event counts separate from case-person counts.
Flow diagram
Steps
Define event and case criteria
Specify incident or recurrent events and the source population.
Establish observation eligibility
Define observation independently of the event where required by the chosen method.
Identify qualifying cases
Include people with relevant events under documented ascertainment rules.
Review event-related selection
Assess mortality, censoring or exposure changes caused by events.
Retain event histories
Link repeated events and source evidence without treating events as independent people.
Included cases
Record people using the documented inclusion definition. This count is not a disjoint partition of the other count nodes.
Qualifying events
Record events using the documented inclusion definition. This count is not a disjoint partition of the other count nodes.
Self-controlled case and event selection
End flow
Tables and supporting information
Case and event definitions
Keep person and event units distinct.
Assumptions and rationale
Standard SCCS assumptions may fail when events affect exposure or observation; such settings need justified extensions.
Method and protocol evidence
Attach the protocol, methodological sources and versioned software specification supporting these decisions. Record citations and provenance; do not enter participant identifiers.