Dimensions of quality explored by different scales^*

Scale and study No. of levels Study design Quality of conduct Consistency of results Canadian Task Force, 19903 4 X US Preventive Services Task Force, 19964 5 X AHCPR, 199211 5 X Guyatt et al., 199512 6 X X Eccles et al, 199610 6 X Hadorn et al, 199613 7 X X Ball et al, 199714 10 X X X Liddle et al, 199715 5 X X X Jovell et al, 199716 9 X X X AHCPR = Agency for Health Care Policy and Research.

^* An "X" indicates an area explored; a blank space indicates it was not addressed by the study.