Journal of Clinical Epidemiology
Journal of Clinical Epidemiology > 2007 > 60 > 2 > 192-201
Journal of Clinical Epidemiology > 2007 > 60 > 2 > 181-191
Journal of Clinical Epidemiology > 2007 > 60 > 2 > 192-201
Journal of Clinical Epidemiology > 2007 > 60 > 2 > 181-191