This study examined psychometric properties and feasibility of the Family Psychoeducation (FPE) Fidelity Scale. Fidelity assessors conducted reviews using the FPE fidelity scale four times over 18 months at five sites in Norway. After completing fidelity reviews, assessors rated feasibility of the fidelity review process. The FPE fidelity scale showed excellent interrater reliability (.99), interrater item agreement (88%), and internal consistency (mean = .84 across four time points). By the 18-month follow-up, all five sites increased fidelity and three reached adequate fidelity. Fidelity assessors rated feasibility as excellent. The FPE fidelity scale has good psychometric properties and is feasible for evaluating the implementation of FPE programs. Trial registration ClinicalTrials.gov Identifier: NCT03271242.
Keywords: FPE fidelity scale; Family psychoeducation; Psychometric properties; Psychosis.