J. Newhouse, and M. McClellan. Annual review of public health, (January 1998)4083<m:linebreak></m:linebreak>LR: 20051116; PUBM: Print; JID: 8006431; RF: 16; ppublish;<m:linebreak></m:linebreak>Variables instrumentals.
L. Silva-Ayçaguer, P. Suárez-Gil, and A. Fernández-Somoano. BMC medical research methodology, (January 2010)5769<m:linebreak></m:linebreak>JID: 100968545; OID: NLM: PMC2886084; 2009/12/29 received; 2010/05/19 accepted; 2010/05/19 aheadofprint; epublish;<m:linebreak></m:linebreak>Significació estadística.
F. Babl, and A. Davidson. Emergency medicine Australasia : EMA, 22 (5):
407-17(October 2010)6205<m:linebreak></m:linebreak>CI: (c) 2010 The Authors. Emergency Medicine Australasia (c) 2010; JID: 101199824; CIN: Emerg Med Australas. 2011 Feb;23(1):108. PMID: 21284823; 2010/08/18 aheadofprint; ppublish;<m:linebreak></m:linebreak>Disseny; Introductori; Urgències.
R. Omar, N. McNally, G. Ambler, and A. Pollock. BMC health services research, (January 2006)4119<m:linebreak></m:linebreak>PUBM: Electronic; DEP: 20060112; JID: 101088677; 2005/05/27 received; 2006/01/12 accepted; 2006/01/12 aheadofprint; epublish;<m:linebreak></m:linebreak>Recursos/Organització; Necessitats.