Which method of suicide should the nurse identify as most lethal?

The method identified as most lethal in this context is the use of a gun. This choice is supported by statistical evidence indicating that firearms are one of the leading means of suicide completion. The lethality associated with using a gun stems from the immediate and irreversible nature of the injuries typically sustained, which often results in a high likelihood of fatality.

In contrast, other methods listed, such as aspirin overdose, head-banging, or wrist-cutting, generally carry lower rates of fatality. While an aspirin overdose can potentially be harmful or even lethal, it often requires a significant amount to reach fatal levels and may allow for medical intervention to prevent death. Similarly, head-banging and wrist-cutting are associated with lower lethality largely because there are avenues for intervention that can often prevent fatal consequences. Overall, the immediacy and severity of injuries caused by gunshot wounds place this method in a category of its own regarding lethality in suicide attempts.