00415nas a2200169   4500000000100000000000100001008004100002100001700043700001500060700001300075700001600088700001800104245009200122300001000214490000700224022001400231       2011                            d1 aC. Salisbury1 aL. Johnson1 aS. Purdy1 aJ. Valderas1 aA. Montgomery00aEpidemiology and impact of multimorbidity in primary care: a retrospective cohort study  a12-210 v61  a0960-1643