We performed field testing of a previously described group education program for type 2 diabetes. HbA(1c) levels at start, 6 and 12 months were collected and demographic factors examined to identify predictors of long-term glycemic control on individual and group levels. "Glycemic success" comprised of (1) achieving target values of HbA(1c) < or =6.5% and/or (2) decreasing HbA(1c) progressively, depending on initial values. Groups in the field test and previous pilot-study (N=105) decreased their mean HbA(1c) significantly after 6 months, implying that diabetes mass education led by pharmacists could be possible in the future. Target HbA(1c) < or =6.5% was seen in 51% at start and 63% after 12 months (P=0.023). Initial HbA(1c) and BMI were the most important success predictors; age, sex, duration, and civil status showed no effects. Overweight individuals relapsed after initially decreasing their HbA(1c), emphasizing the need for long-term support in weight management. Experienced loneliness affected outcomes, indicating interaction between diet self-care and social relations.