RT Journal T1 MEchanical therapeutic agencies.the salt of the earth. JF JAMA JO JAMA YR 2002 FD October 16 VO 288 IS 15 SP 1920 OP 1920 DO 10.1001/jama.288.15.1920 UL http://dx.doi.org/10.1001/jama.288.15.1920 AB