Lacking Dr. Discipline in South Dakota?

A KXMC article features a report from a group called Public Citizen which says South Dakota has the fourth worse record for doctor discipline in the U.S.:

A report by Public Citizen shows that just four of the two-thousand doctors in South Dakota were disciplined during the two-year period.

The state's disciplinary rate was less than half the national average.

Public Citizen was founded by far-Leftist Ralph Nader, so take analysis of the conclusions with a grain of salt.