Orderly display of limb lead ECGs raises Chinese intern’s diagnostic accuracy when determining frontal plane QRS axis

Background: There is limited information on whether the orderly display of limb lead ECGs (electrocardiograms) can facilitate students to determine frontal plane QRS complex wave electrical axis. Objectives: The study investigated whether the orderly display of limb lead ECGs can raise Chinese undergraduate intern’s diagnostic accuracy when determining frontal plane axis. Design: A total of 147 fifth-year undergraduate interns aged between 21 and 25 years were randomly arranged into 2 groups: one group was given classically displayed ECGs of limb leads while the other group was given orderly displayed ECGs of limb leads. They were then taught to determine frontal plane axis with one of the above displays. The intern’s diagnostic accuracy and time used were measured. Results: After teaching, the orderly display can more effectively raise diagnostic accuracy when determining axis as compared to the classical display (76.65 ± 23.16% vs. 68.88 ± 23.21%, P < 0.05), although diagnostic accuracy in axis determination was improved in both groups as compared to the axis determination at baseline (all P < 0.05). Conclusions: Orderly display of limb lead ECGs may raise Chinese intern’s diagnostic accuracy when determining frontal plane axis.