FIGURE 2.

Representative images shown to 22 expert participants. Upper left, Image was classified as “neither plus nor pre-plus” by all 22 experts (100%). Upper middle, Image was classified as “plus” by 2 experts (9.5%), “pre-plus” by 9 (42.9%), “neither” by 10 (47.6%), and “cannot determine” by 1 expert. Upper right, Image was classified as “plus” by 1 expert (4.8%), “pre-plus” by 16 experts (76.2%), “neither” by 4 (19.0%), and “cannot determine” by 1 expert. Lower left, Image was classified as “plus” by 11 experts (52.4%), “pre-plus” by 10 (47.6%), and “cannot determine” by 1 expert. Lower middle, Image was classified as “plus” by all 22 experts (100%). Lower right, Image was classified as “plus” by 3 experts (14.3%), “pre-plus” by 9 (42.9%), “neither” by 9 (42.9%), and “cannot determine” by 1 expert.