00653nas a2200241   4500000000100000000000100001008004100002100003200043700001500075700001100090700001300101700001700114700001400131700001600145700001600161700001500177700001600192700001400208245016000222300000800382490000700390022001400397       2018                            d1 aJ. O\textquoterightSullivan1 aS. Stevens1 aJ. Oke1 aF. Hobbs1 aC. Salisbury1 aP. Little1 aB. Goldacre1 aC. Bankhead1 aJ. Aronson1 aC. Heneghan1 aR. Perera00aPractice variation in the use of tests in UK primary care: a retrospective analysis of 16 million tests performed over 3.3 million patient years in 2015/16  a2290 v16  a1741-7015