General practitioner phone calls to improve COVID-19 vaccine uptake among patients at increased risk of severe COVID-19: A randomised trial.
Marit TuvIngeborg Hess ElgersmaEllen FurusethChristine HolstArnfinn HelleveAtle FretheimPublished in: BJGP open (2023)
ClinicalTrials.gov Identifier NCT05207137.