Final answer:
The most important tool for overall patient safety is the use of checklists.
Step-by-step explanation:
The most important tool for overall patient safety, as highlighted in the IOM report: To Err is Human, is the use of checklists. Drs. Gawande and Pronovost developed and implemented checklists in healthcare settings to improve accuracy and prevent errors. These checklists ensure that healthcare professionals follow all necessary steps and protocols, reducing the risk of complications and improving patient outcomes.