Table 2

 CPR performance for untrained and trained rescuers. Rescuers performed CPR twice, once with and once without audio prompts. Data are given as mean (SD)

Attempt numberUntrained rescuerTrained rescuer
1212
*Indicates significant difference (p<0.05) between attempt 1 and attempt 2 within a group (either prompts first or no prompts first) with **indicating p <0.01 and ***p<0.001, paired t test. †Indicates significant difference (p<0.05) between groups (prompts first compared with no prompts first), with ††indicating p<0.01 and †††p<0.001, unpaired t test. ‡Indicates significant difference (p <0.05) between untrained and trained rescuers within a group (either prompts first or no prompts first) for a given attempt, with ‡‡indicates p<0.01, paired t test.
% Compressions correct depth:
    Prompts first34.4 (35.7)42.9 (36.0)42.2 (35.2)46.7 (36.2)
    No prompts first36.0 (33.3)30.7 (31.3)36.6 (32.0)39.2 (31.1)
% Compressions correct hand position:
    Prompts first76.0 (35.6)69.6 (40.4)79.9 (25.6)85.7 (20.4)
    No prompts first54.1 (44.2)67.8 (42.7)81.1 (27.9)71.7 (36.3)
% Correct compressions (position and depth):
    Prompts first18.8 (27.2)25.7 (32.5)25.2 (27.2)29.6 (24.6)
    No prompts first24.5 (32.2)23.3 (29.4)16.7 (23.9)25.4 (33.6)
Mean compression rate:
    Prompts first87.3 (19.4)86.2 (19.9)99.0 (3.7)‡99.1 (7.1)‡
    No prompts first52.3 (31.4)††91.6 (12.1)***94.5 (11.4)‡93.1 (15.2)
% Correct ventilations:
    Prompts first51.3 (34.4)41.6 (33.3)84.8 (22.9)‡‡77.2 (31.0)‡‡
    No prompts first15.3 (32.8)††47.2 (40.0)**55.5 (43.3)‡‡65.8 (36.5)‡‡