METHODS

Design:

randomised controlled trial.

Allocation:

unclear allocation concealment.*

Blinding:

blinded {study nurse and laboratory staff}†.*

Follow up period:

Median 7 years (median 3 y postintervention).

Setting:

5 centres in Finland.

Patients:

522 patients {40–65 years of age}† (mean age 55 y, 67% women) with {body mass index ⩾25 kg/m²}† (mean 31 kg/m²) and impaired glucose tolerance {(plasma glucose level 140–200 mg/dl [7.8–11.0 mmol/l] 2 h after a 75 g oral glucose tolerance test and fasting plasma glucose level <140 mg/dl [7.8 mmol/l])}† on 2 occasions. Exclusion criteria included {previous diagnosis of diabetes and life expectancy <6 y}†.

Intervention:

lifestyle intervention, involving a median 20 individual dietary counselling sessions with a nutritionist and advice …