RT Journal Article SR Electronic T1 Seeing the wood and the trees: the impact of the healthcare system on variation in primary care referrals JF BMJ Quality & Safety JO BMJ Qual Saf FD BMJ Publishing Group Ltd SP 274 OP 276 DO 10.1136/bmjqs-2019-010356 VO 29 IS 4 A1 Round, Thomas A1 Abel, Gary YR 2020 UL http://qualitysafety.bmj.com/content/29/4/274.abstract AB