Study design
This is a pragmatic randomized controlled educational intervention among Norwegian telephone triage nurses working in out-of-hours GP cooperatives. All Norwegian out-of-hours GP cooperatives that met our inclusion criteria were included in the study (Table Inclusion criteria for out-of-hours GP cooperativesThe out-of-hours services in the two largest cities of Norway, Bergen, and Oslo, were not included owing to their policy of direct attendance. Out-of-hours cooperatives serving less than 10,000 inhabitants were excluded as they normally will have less than 6 consultations per 24 hours and therefore are less busy [A total of 64 out-of-hours GP cooperatives serving 3.4 million inhabitants (median population size per out-of-hours GP cooperative 36.048, range 11.490–236.202) met the inclusion criteria and were randomized to intervention or control. An independent researcher performed the randomization using the RAND command in Microsoft Excel (2016) in November 2018, with stratification by the population size (small 10,000–40,000; large > 40,001).We contacted the administration of the 32 out-of-hours cooperatives in the intervention group through e-mail or telephone and invited them to participate in a meeting during the annual leadership conference for the primary care out-of-hours service in Norway (Lederkonferansen 2019) in March 2019. In this meeting, we presented the educational intervention and explained how they could implement it locally without any external support. Nineteen persons from 16 out-of-hours GP cooperatives participated. BHL contacted the other 16 out-of-hours GP cooperatives, three by personal contact during the conference and the remaining via telephone calls after the conference. One of the 32 cooperatives refused to participate due to time constraint, while the other 31 accepted the invitation and were included in the study. Data from one out-of-hours cooperative in the intervention group, in addition to one out-of-hours cooperative and one municipality in the control group, were excluded from the study because of the merging of municipalities across the two groups during the study period. Data from two out-of-hours cooperatives (serving 180,989 inhabitants) in the control group were excluded because of data error. As a result, 59 out-of-hours GP cooperatives serving 59% of the Norwegian population, were included in the intention-to-treat analysis (Fig. Flow chart of out-of-hours cooperatives included and reasons for exclusion after randomization