Final answer:
The most accurate method to determine the number of patients treated for shortness of breath with a history of CHF is by reviewing previous prehospital care reports, which contain detailed and official patient records.
Step-by-step explanation:
To best determine the number of patients treated for shortness of breath with a history of congestive heart failure (CHF) over the past year, you would Review the previous prehospital care reports. This method would provide the most accurate, comprehensive, and official record of all patients with this condition that were treated. Surveys and questioning staff are less reliable and may not capture every case or the specifics of each patient's condition. The prehospital care reports should include detailed information that can be analyzed to assess trends and the number of patients affected by CHF with associated shortness of breath.