The Ministry of Health says figures showing a 44 % increase in the number of people with diabetes in the Hutt Valley are correct.
Hutt Valley District Health Board members heard on Tuesday that, according to ministry estimates, the number of people in the area with diabetes rose by 44% between 2006 and 2007 to more than 4,100.
The DHB said it would be checking with the ministry about the big increase over one year.
The ministry's chief clinical adviser, Sandy Dawson, says the revised estimate is correct and is based on more accurate modelling nationwide.
Dr Dawson says the more accurate information will improve treatment for those with diabetes.
Free annual checks for those with the condition have risen by 20% over the past four years.
Board members want more information on changes by the ministry to its diabetes model and on what the DHB is doing to cope with increasing diabetes in the area it serves.