The feasibility, effects and cost-effectiveness of environmental interventions aimed at changing
01 / 1996 - unknown
The main purpose of the project is to study the feasibility and effects of two environmental interventions (i.e. food labeling and changes in food supply) aiming at reducing fat intake and increasing fruit and vegetable consumption in combination with a standard educational intervention, in two point of choice settings (i.e. worksite cafetarias and supermarkets). The project will also assess the cost effectiveness of these environmental interventions. Preparation phase First of all, interviews will be conducted with key persons to assess the conditions for adoption and continued implementation of the environmental interventions in the two settings. Based on the results of this study the environmental interventions will be planned and the necessary materials will be developed in conjunction with potential adopters. Interventions in the food labeling program, (foods with) fruit and vegetables and low-fat products in selected product categories will be labeled. Also, large charts on the wall will indicate the grams of fat of all products in the selected product categories. In the changes in food supply program, more (foods with) fruit and vegetables will be offered and at least one additional low-fat item will be supplied in selected product categories. The educational program will consist of posters, brochures, a self-help manual and table tents or audio system messages. All program materials will be pretested before implementation. Design Two field experiments will be conducted. One field experiment will be conducted in worksite cafetarias and one in supermarkets. Each field experiment will have four experimental conditions: an education only condition, an education plus food labeling condition, an education plus changes in food supply condition, and a control condition where no intervention will be implemented. In both field experiments four cafetarias/supermarkets will be randomly assigned to each condition. Methods Sales data will be collected to assess the effects of the interventions on the purchase of labeled/new food items as well as on non-labeled/already available food items. In addition to this, questionnaires will be completed by random cohort research samples of customers, before, one month and six months after intervention implementation to assess effects on determinants of behavior, stage of behavioral change, individual level purchase and consumption data of food items and overall daily fat intake and fruit and vegetable consumption. Furthermore, process evaluation data will be collected. To assess the feasibility and implementation of the interventions, the implementation will be monitored and interviews will be conducted with people involved in the implementation. To assess cost-effectiveness, the effects of the different intervention strategies will be divided by their costs. Expected results after the proposed study, the effects that environmental interventions can add to educational programs in changing chronic disease related dietary behaviors will be known as well as how these strategies should be implemented.