Participants were a total of 5,145 men and women who were recruited at 16 centers across the U.S. As described previously (4 ,13 (link)), participation was open to persons with type 2 diabetes who were 45 to 74 years of age and had a body mass index (BMI) ≥ 25 kg/m2 (or ≥ 27 kg/m2 if taking insulin). (The lower age criterion was raised to 55 years in the second year of recruitment to increase the rate of anticipated cardiovascular events.) For safety, participants were required to have blood pressure ≤ 160/100 mm Hg, hemoglobin A1c ≤ 11%, and triglyceride levels < 600 mg/dl. These measures were obtained during a screening visit, after applicants gave their written informed consent to participate (following guidelines of the Helsinki Declaration and each site’s institutional review board). In addition, applicants completed a graded exercise test, described previously (1 (link),4 ,14 ), to ensure that they could safely adhere to the physical activity program prescribed in the ILI (15 (link)). All applicants also were required to have a primary care provider who would be responsible for providing their medical care (including for cardiovascular risk factors) during the 11.5 year trial.
In addition to these safety criteria, applicants were required to pass a test of behavioral adherence which consisted of recording their food intake and physical activity for two consecutive weeks. Candidates who did not keep satisfactory records for at least 12 of 14 days were not eligible to participate. This adherence criterion was included to facilitate the selection of highly motivated individuals who could meet the study’s weight and activity goals.
Participants reported their age, education, race/ethnicity, and other demographic characteristics. The study’s recruitment goals were to enroll approximately equal numbers of men and women, with ≥ 33% of participants from racial and ethnic minority groups.
In addition to these safety criteria, applicants were required to pass a test of behavioral adherence which consisted of recording their food intake and physical activity for two consecutive weeks. Candidates who did not keep satisfactory records for at least 12 of 14 days were not eligible to participate. This adherence criterion was included to facilitate the selection of highly motivated individuals who could meet the study’s weight and activity goals.
Participants reported their age, education, race/ethnicity, and other demographic characteristics. The study’s recruitment goals were to enroll approximately equal numbers of men and women, with ≥ 33% of participants from racial and ethnic minority groups.
