“…<29 only 11 Denmark [42,45], the Netherlands [25,28,36], Norway [70,71], Sweden [49,52,53,54], UK [62] both <29 and >29 12 Denmark [41,45], Estonia [72], France [74], Germany [68], Slovenia [77], Spain [79], Sweden [48], UK [24,55,56,57] In terms of geographic coverage, five population-based studies included a nationally representative sample of the general adult population (France [74], Germany [68,69], the Netherlands [28], Slovenia [77], UK [57]), and one a similar sample of the child and adolescent population (Germany [63]). All surveys used stratified random sampling methods to select a study sample that represented the national population.…”