Period prevalence data expressed by age range and gender. Data are not reported for prevalence of cervicothoracic and thoracolumbar pain (4 studies). In studies where an age range was reported, the median age was calculated for the 'age range' variable. Studies reporting only a minimum age for inclusion were excluded from the Figure [51, 56]. Therefore, the Figure shows data from five studies which reported point prevalence, 6 for 1-week prevalence, 6 for 1-month prevalence, 1 for 3-month prevalence, 6 for 1-year prevalence, and 3 for lifetime prevalence.