Thursday's post on primary care physicians' patient loads sparked some debate among doctors, a number of whom have contacted me. But the most useful information was a reminder of a survey by Merritt Hawkins, a physician search and consulting firm that questioned 1,399 medical offices last year to determine wait times for new patient appointments  in various specialties. (The Washington Post ran a story on this in February, so I'm repeating here.)

Boston averages the longest time for a first appointment among the 15 cities surveyed: 45 days. That includes 72 days to see a dermatologist for the first time and 66 days to see a family physician. Boston has earned this dubious distinction in all three surveys the firm has conducted.

Dallas had the shortest wait times, none of them more than 45 days (to see an orthopedic surgeon).

Cities tend to have a higher ratio of doctors to population than rural areas do, so the reason appears to be that demand is simply outstripping supply, as the data I wrote about Thursday seemed to indicate.

These two charts pretty much tell the whole story.