Expanding the criteria for defining success when evaluating weight loss intervention programs

In order to evaluate outcomes among former participants in a residential weight loss program, attendees were surveyed from 1 to 5 years post-intervention. A total of 187 respondents were studied for weight changes and behavioral practices. Diet practices were assessed by number of servings per day using the Food Guide Pyramid recommendations as a guideline for indicating fruit and vegetable intake. Exercise behaviors were measured in frequency, duration, and intensity, and a weighted score was computed to obtain units for describing physical activity. Maintaining a 10% weight loss from the program entry weight, consuming five or more servings per day of fruits and/or vegetables (5-a-day) and maintaining an "active" level of physical activity were included in criteria for describing intervention success. Those meeting two of the three criteria were categorized as "successful," which included 35.8% of the study population. Because each of these behaviors (5-a-day, active lifestyle, and modest weight loss maintenance) result in independent risk reduction, it is recommended that future weight loss intervention evaluations expand the criteria for describing successful impacts and outcomes to include not only weight maintenance, but also physical activity and diet compliance behaviors.