“…There was an equal number of studies in IBD 35, 39–42, 46, 58 and RA 34, 36, 37, 43, 60–62 , with 1 study combining both populations 59 and 1 study in psoriasis 62 . Ten studies were population-based 34–38, 43, 46, 59, 60, 62 and 12 studies adopted a cohort design 34–38, 40, 41, 43, 46, 59, 60, 62 . Three were from North America 40, 58, 59 , twelve from Europe 34–39, 41–43, 46, 60, 62 , and one from Asia 61 .…”