TY - STAND AU - N. Khan AU - S. Harrison AU - P. Rose BT - Br J Gen Pract DO - 10.3399/bjgp10X483562 M1 - 572 PY - 2010 SP - 128 EP - 36 T2 - Br J Gen Pract TI - Validity of diagnostic coding within the General Practice Research Database: a systematic review VL - 60 SN - 0960-1643 ER -