Target trial specification
Target protocol → eligibility and strategies → assignment emulation → aligned time zero → follow-up and estimand
Flow diagram
Steps
Target protocol and causal question
Specify the trial that the observational analysis aims to emulate.
Eligibility and treatment strategies
Define eligibility before assignment and the strategies being compared.
Assignment emulation and confounding
Specify how observed assignment will be handled and which confounders are available.
Align eligibility, assignment and time zero
Align the three time origins to avoid selection from future information.
Follow-up, outcomes and censoring
Define outcome capture, risk windows, censoring and competing events.
Causal contrast and analysis
Specify the estimand and analysis approach.
Feasibility gaps and bias assessment
Identify protocol elements that cannot be emulated and assess their implications.
Tables and supporting information
Target protocol to data mapping
Document deviations explicitly rather than assuming equivalence.
Identification assumptions
Specify exchangeability, consistency, positivity and measurement assumptions where applicable.
Protocol and supporting evidence
Record target protocol and methodological references.