Final answer:
The fifth step of analyzing an ECG rhythm is to evaluate the PR intervals, which gives information on the rhythm's origin and atrioventricular conduction.
Step-by-step explanation:
The fifth step in analyzing an ECG rhythm is to evaluate the PR intervals. The PR interval measures the time from the start of the P wave (atrial depolarization) to the start of the QRS complex (ventricular depolarization) and reflects the time the electrical impulse takes to travel from the sinoatrial (SA) node through the AV node, down the bundle of His, and to the Purkinje fibers. With a normal ECG, which includes the P wave, QRS complex, and T wave, the evaluation of the PR interval can provide valuable information regarding the rhythm's origin and whether there is any delay in atrioventricular conduction.