Discussion
psychotic disorders, BFIS
CORONAVIRUS
The results show that the ISP had a significant and substantial effect on the adherence to the national guidelines in participating clusters, compared to manual/guideline only. At 24 months, the mean scores on all fidelity scales were four or higher in the experimental arm, suggesting adequate to excellent levels of implementation.Structural elements of the BFIS scale such as implementation team, family coordinator, and procedures for family involvement were implemented during the first 6 months of the implementation period in the experimental arm, as demonstrated by the sharp rise in BFIS-S scores. By comparison, the BFIS-P scores increased progressively throughout the trial, probably reflecting that time is required for organisational and procedural changes to reach patients and relatives (Bond et al., At 24 months, all experimental sites offered FPE with adequate fidelity (≥ 4) and a mean score of 4.48. The progressive nature of the FPE model probably explains the gradual increase in scores in the experimental arm. The success rate is good compared to previous studies, which report mean scores of 3.30–4.00 and 39–50% of sites reaching adequate fidelity after 18–24 months of implementation support (Bond et al., The GOI scale was used to investigate critical implementation factors beyond fidelity (Heiervang et al., The substantial improvements in FPE fidelity and GOI scores in the experimental arm were not accompanied by large increases in the penetration rate of FPE. This might be related to capacity issues, the relatively short observation time, and the coronavirus pandemic (see below). By not including discharged patients who had received FPE, the numbers may also systematically underestimate the effort of the clinical sites. In contrast, the mean score on the BFIS-P subscale indicates that the penetration rate of basic family involvement practices rose to 60–80% across items in the experimental arm at 24 months. BFIS practices are less time-consuming than FPE and were usually implemented as standardised procedures towards all patients at the clinical sites, which may explain some of the difference in penetration rate. When calculating the penetration rates, we assumed that all patients with psychotic disorders were eligible for BFIS and FPE, which probably is an overestimation, particularly with regard to FPE (Haahr et al., Similar to the implementation model of the NEBP project (Bond et al., The IFIP implementation strategy also differed from those of previous multi-centre fidelity-based studies on the implementation of FPE (Kealey et al., The first coronavirus pandemic lockdown in Norway began approximately 2 months before the fidelity measurements at 18 months. The consequent lack of newly started FPE groups in the last 7–8 months of the implementation period contributed to the dip in FPE penetration rate seen at 18 and 24 months. Fidelity scores did not appear to be similarly affected, but it is difficult to ascertain whether the results could have been different. The lack of data points at 12 and 18 months in the control arm makes it harder to assess the influence of such external factors, but it is likely that the respective arms were affected to the same degree.