GP phone calls to improve COVID-19 vaccine uptake among patients at increased risk of severe COVID-19: a randomised trial

BACKGROUND: English media have reported that many unvaccinated individuals took the COVID-19 vaccine after receiving a phone call from their GP. AIM: To determine whether phone calls from GPs to unvaccinated patients at increased risk of severe COVID-19 improves uptake of the COVID-19 vaccine. DESIGN & SETTING: Randomised trial where 202 participants were allocated to receive a phone call from their GP, and 452 participants were allocated to not get the call. Twenty-five GPs at 11 medical centres in Norway took part. The post-trial focus group discussion was with five GPs. METHOD: Participants were sourced from the GP electronic medical record system, which communicates with the Norwegian Immunisation Registry and can generate a list of the GPs’ unvaccinated patients at increased risk of severe COVID-19. RESULTS: The GPs managed to speak over the phone with 154 (76%) patients allocated to receiving a phone call. At follow-up (average 7.5 weeks), 8.9% in the intervention group and 5.3% in the control group had been vaccinated (odds ratio [OR] 1.72; 95% confidence interval [CI] = 0.90 to 3.28). Findings from the focus group discussion suggested the timing of the intervention as a likely key reason for its limited success. CONCLUSION: An increase in the proportion of patients who took the COVID-19 vaccine in the intervention group was observed, but the difference was smaller than anticipated, and may be a chance finding. The effect of this type of intervention will likely vary across contexts and may have proved more effective if a larger proportion of the population were unvaccinated.