Results
One hundred and eighty four potentially relevant studies were identified, of which 112 were retrieved for detailed evaluation. Following exclusion of ineligible studies, 16
were included in the review (Figure 1). Additional File 1 summarises the characteristics of the 16 included studies. Study participants varied considerably by gender (0-100% male) and health status. Mean age of participants in individual studies ranged from 38
to 49 years, and a variety of worksite settings were represented. One international study involved worksites in 17 countries [16]. More than half were undertaken in
North America (n = 9) [17-25], and the remainder were from Europe (n = 6) [26-31]. Study sizes ranged from 84 to 5,156 employees, and from one to 84 worksites.