Lutz, S.F., Ammerman, A.S., Atwood, J.R., Campbell, M.K., DeVellis, R.F., Rosamond, W.D. (1999) J Am Diet Assoc 99(6) 705-9.
OBJECTIVE: To evaluate the effectiveness of computer-tailored newsletter interventions in improving the number and variety of fruits and vegetables eaten by adults.
DESIGN: The 4-group randomized trial with pre- and postintervention measures consisted of a control group and 3 intervention groups receiving nontailored newsletters, computer-tailored newsletters, or tailored newsletters with tailored goal-setting information. Intervention groups received 1 newsletter each month for 4 months.
SUBJECTS: Baseline surveys were completed by 710 health maintenance organization clients. Postintervention surveys administered 6 months after baseline were completed by 573 participants (80.8%).
INTERVENTION: All newsletters contained strategies for improving fruit and vegetable consumption. Tailored newsletters used computer algorithms to match a person's baseline survey information with the most relevant newsletter messages for promoting dietary change.
MAIN OUTCOME MEASURES: Daily intake and weekly variety of fruits and vegetables were measured using a food frequency questionnaire.
STATISTICAL ANALYSES PERFORMED: Analysis of covariance and Tukey's honestly significant difference test were used to assess differences in the number and variety of fruits and vegetables consumed among intervention groups.
RESULTS: For persons completing postintervention surveys (n = 573), all 3 newsletter groups had significantly higher daily intake and variety scores compared with the control group. Although there was a trend of improved intake and variety with each added newsletter element, there were no significant differences at follow-up among the newsletter groups.
CONCLUSIONS: Newsletters can be effective in improving the fruit and vegetable consumption of adults. In this study, a computer-tailoring system did not significantly enhance the effect of the nutrition newsletters on fruit and vegetable intake.