How do we evaluate the cost of nosocomial infection? The ECONI protocol: an incidence study with nested case-control evaluating cost and quality of life oleh Helen Mason, Sally Stewart, Elaine Ross, Sarkis Manoukian, Lynne Haahr, Agi McFarland, Jacqui Reilly, Mahmood Adil, Alistair Leanord, Rachel Dunk, Abigail Mullings, Lisa Ritchie, Moira Whyte