But a DHB spokeswoman said it was "impossible to compare DHBs".
"The DHB employs nearly 2800 staff and the numbers who have faced disciplinary action has stayed negligible at about 0.42 per cent over the past five years."
There had been nine incidents requiring disciplinary action from January to September last year.
There had been 12 incidents in 2013, and a five-year high of 16 incidents in 2012.
There were 12 incidents in each of the two years prior.
"DHBs collect data in different ways with different parameters, which makes it impossible to compare DHBs. We don't know what staff other DHBs included in their response, or what they defined as disciplinary action," the spokeswoman said.
DHB acting chief executive Tim Evans said the DHB was confident it had the right measures and processes in place to discourage inappropriate behaviour and the numbers reported were "statistically negligible" compared to the number of staff employed.
There had not been any increase in reported incidents requiring disciplinary action over time.
"Disciplinary action is, and should be, a rare event," Mr Evans said.
"Patient safety is paramount and disciplinary action is part of ensuring a consistent and quality service to our community,"