METHODS OF DIETARY AND NUTRITIONAL ASSESSMENT AND INTERVENTION AND OTHER METHODS IN THE MULTIPLE RISK FACTOR INTERVENTION TRIAL

Various dietary assessment instruments were used in the Multiple Risk Factor Intervention Trial (MRFIT), either to assist with the special i ntervention program or to assess trial outcomes. For the latter purpos e, the 24-h recall was the main method and was selected with the under standing that the single recall collected at baseline and at most annu al visits-considered by itself-would be useful mainly for assessing gr oups rather than individuals. Major components of the data collection and analysis system developed for the 24-h recall included central tra ining and certification of nutritionists, a central nutrient coding sy stem, and a food grouping system to assist interventionists in using r ecall data for counseling. Several additional nutritional assessment m ethods were used for men in the special intervention group only to ass ist them in attaining the dietary goals. These goals consisted chiefly of reduced intake of saturated fat and cholesterol and a modest incre ase in intake of polyunsaturated fat; total fat intake was also decrea sed, primarily for control of energy intake. Shortterm success at atta inment of these nutritional goals was evaluated by means of 3-d food r ecords collected before the intervention and after the initial 10-wk i ntensive intervention period. The MRFIT nutrient goals, which became m ore vigorous at certain points in the trial, were translated into food patterns. Adherence to these food patterns was also assessed by scori ng of 3-d records and by subjective evaluation by nutritionists throug hout the trial. Methods of collecting other trial data are also descri bed in this chapter.