‘Caveat emptor’: the cautionary tale of endocarditis and the potential pitfalls of clinical coding data—an electronic health records study af Fawcett, N, Young, B, Peto, L, Quan, TP, Gillott, R, Wu, J, Middlemass, C, Weston, S, Crook, DW, Peto, TEA, Muller-Pebody, B, Johnson, A, Walker, AS, Sandoe, J