Cluster and participant recruitment

Track both levels of enrollment

Clusters and people are different units. Recruitment after allocation can introduce selection if knowledge of treatment affects entry; document timing, masking and consent at both levels.

Flow diagram

Cluster and participant recruitmentF1.S1Define eligible clustersF1.S2Recruit clustersF1.S3Define participant samplingF1.S4Document timing relative toallocationF1.S5Track both levels of enrollmentF1.S6Enrolled clustersF1.S7Enrolled participantsF1.N1Multilevel enrollment rulesLevelEligibilityRecruitmenttimingConsentExclusionreasonsClustersParticipantsF1.N2Assumptions and rationaleF1.N3Method and protocol evidenceF1.S0 Start flowCluster and participant recruitmentF1.S999 End flowEnd flow

Steps

Define eligible clusters

Specify sites, practices or other groups and cluster-level consent.

Recruit clusters

Record approach, eligibility, participation and reasons for nonparticipation.

Define participant sampling

Specify eligible people within clusters and sampling opportunities.

Document timing relative to allocation

Identify recruitment before or after cluster assignment and blinding safeguards.

Track both levels of enrollment

Keep cluster counts and participant counts in separate ledgers.

Enrolled clusters

Record clusters using the documented inclusion definition. This count is not a disjoint partition of the other count nodes.

Enrolled participants

Record people using the documented inclusion definition. This count is not a disjoint partition of the other count nodes.

Cluster and participant recruitment

End flow

Tables and supporting information

Multilevel enrollment rules

Multilevel enrollment rulesLevelEligibilityRecruitmenttimingConsentExclusionreasonsClustersParticipants

Keep denominators and losses separate; no cluster-to-person sum is valid.

Assumptions and rationale

Recruitment after allocation may introduce selection bias; document safeguards and assessor knowledge.

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.

Sources