http://www.aafp.org/afp/2002/0401/p1423.html http://www.aafp.org/afp/2002/0401/p1423.html http://www.aafp.org/afp/2002/0401/p1423.html http://www.aafp.org/afp/2002/0401/p1423.html http://www.aafp.org/afp/2002/0401/p1423.html American Academy of Family Physicians