References
Eepidemiology by Greenberg and coworkers (2000).
Hulley and Cummings (2001) Clinical Research.
Garb (1996) Study Design in Medicine
Burns and Grove (2002) (Nursing)]
References
Eepidemiology by Greenberg and coworkers (2000).
Hulley and Cummings (2001) Clinical Research.
Garb (1996) Study Design in Medicine
Burns and Grove (2002) (Nursing)]