Vaccine acceptability, uptake and completion amongst men who have sex with men: a systematic review, meta-analysis and theoretical framework

Background: Due to an increased risk of sexually transmitted infections (STIs), gay, bisexual and other men who have sex with men (MSM) have been recommended to receive vaccinations against human papillomavirus, meningitis C and hepatitis A/B. This review aimed to compare the rates of vaccine accept ability, uptake and completion, and to identify determinants of vaccine outcomes specific to MSM to inform a theoretical framework. Methods: In January 2020 four databases were explored to identify vaccination behaviours and associ ated factors among MSM. A narrative systematic review and meta-analysis were performed. Data were synthesised for theoretical modelling. Results: Seventy-eight studies, mostly from the USA, were included. The average vaccine acceptability was 63% (median = 72%, range: 30%-97%), vaccine uptake 45% (median = 42%, range: 5%-100%) and vac cine completion 47% (median = 45%, range: 12%-89%). Six categories of factors associated with vaccina tion acceptability, uptake and completion were conceptualised: Individual (e.g., demographic and psychosocial); Interpersonal (e.g., peer education); Healthcare provider (e.g., vaccine recommendation); Organisational and practice setting (e.g., routine collection of patient sexual orientation information that is integrated into a clinical decision support system); Community environment (e.g., targeted health pro motion campaigns); and National, state and local policy environment (e.g., public health guidelines tar geting MSM). Conclusion: Despite overall high levels of acceptability, uptake and completion rates were below targets predicted by cost-effectiveness modelling across all recommended vaccines. These parameters may need to be adjusted for more precise estimations of cost-effectiveness. Addressing the multiple levels of deter minants, as outlined in our theoretical framework, will help guide interventions to increase vaccine com pletion among MSM