00418nas a2200169   4500000000100000000000100001008004100002100001500043700001400058700001600072700001400088700001200102245010400114300000900218490000700227022001400234       2010                            d1 aE. Herrett1 aS. Thomas1 aW. Schoonen1 aL. Smeeth1 aA. Hall00aValidation and validity of diagnoses in the General Practice Research Database: a systematic review  a4-140 v69  a0306-5251