Why is it important to check responsiveness first when performing CPR?

Checking responsiveness first when performing CPR is vital because it helps determine if the person requires immediate resuscitation efforts. If an individual is unresponsive, it indicates a severe medical emergency, likely requiring CPR to restore breathing and circulation. This step is crucial in the chain of survival, as quickly identifying an unresponsive victim allows for timely intervention, which can significantly increase the chances of survival.

The other choices do not hold the same weight in the context of immediate medical assessment. While providing reassurance to bystanders is important in maintaining calm, it does not directly impact the decision-making process for initiating CPR. Assessing the severity of an injury may be part of a broader evaluation, but in the context of CPR, the immediate concern is assessing responsiveness and the need for resuscitation. Deciding whether a doctor is needed is typically not within the scope of initial CPR actions, as the priority is to stabilize the individual on-site first. Thus, assessing responsiveness directly informs whether to initiate life-saving measures.