Project Overview +

This study tests various interventions to increase fruit and vegetable consumption. Callers to the Cancer Information Service (CIS) receive a brief educational message delivered by an informational specialist while on the phone, followed by mailed untailored and tailored print materials.

Aims +

Aim 1. Design, implement, and evaluate a proactive psychoeducational intervention to promote fruit and vegetable consumption.

Aim 2. Determine which subgroups of callers benefit most from the interventions.

Aim 3. Test for the efficacy and cost-effectiveness of tailored print materials to promote behavior change.

Participants +

3,402 individuals who called NCI's Cancer Information Service.

Intervention +

At the end of usual care services, callers to NCI's Cancer Information Service (CIS) are asked invited to learn more about how to increase their fruit and vegetable consumption. Following a baseline telephone interview, which includes a brief educational message (BEM), participants are randomized to receive by mail, one of the four following sets of fruit and vegetable health education materials:

  • single untailored print communications (SU)
  • single tailored print communications (ST)
  • our tailored print communications spanning 12 months, tailored on baseline data (MT)
  • four tailored print communications spanning 12 months, with retailoring of print materials based on updated 5-month data (MRT)

Process and evaluation data are collected at follow-up phone calls made at 5 and 12 months.

Findings +

Pilot Study 1 Findings:

A single-item measure of fruit and vegetable consumption revealed a significant intervention effect of approximately 0.65 servings per day at 4-week follow-up (P < 0.001) and 0.41 servings per day at 4-month follow-up (P < 0.001). Using a seven-item food frequency measure that was also included in the 4-month interviews, a similar intervention effect of 0.34 servings per day was obtained (P = 0.006). The vast majority of CIS callers (88%) endorsed the strategy of providing 5 A Day information proactively.

Pilot Study 1 Conclusion:

A brief educational intervention delivered to CIS callers at the end of usual service was associated with an increase in self-reported fruit and vegetable intake.

Pilot Study 2 Findings:

Results obtained from a single-item measure of fruit and vegetable consumption indicate a significant intervention effect of 0.88 servings per day at 4 weeks follow-up (P < 0.001), 0.63 servings per day at 4 months follow-up (P < 0.001), and 0.43 servings per day at 12 months follow-up (P < 0.001). Using a 7-item food frequency measure, an intervention effect of 0.63 servings per day was obtained at 4 weeks follow-up (P < 0.001), compared with 0.39 servings per day at 4 months follow-up (P = 0.002) and 0.44 servings per day at 12 months follow-up (P = 0.002). A 24-h recall assessment included in the 4-month interviews also yielded a significant intervention effect of 0.67 servings per day (P = 0.015). The vast majority of callers (90%) endorsed the strategy of providing 5 A Day information proactively within the CIS.

Pilot Study 2 Conclusion:

This brief educational intervention was associated with higher levels of self-reported fruit and vegetable intake at both short- and long-term follow-up.

Final Study Findings:

Follow-up telephone interviews were conducted at 5 (n = 2,233) and 12 months (n = 1,927) after baseline.

  • The main outcome measure was self-reported fruit and vegetable consumption using a seven-item food frequency questionnaire.
  • At 12 months follow-up, there was a significant linear trend across groups of 0.21 servings (p = 0.0002). Specific nested hypotheses then were tested and revealed significant mean serving differences between SU (5.07) vs. MT (5.64) (p = 0.002) and SU vs. MRT (5.71; p < 0.001). Although the mean for ST (5.40) was greater than that for SU (5.07), the difference was not statistically significant (p = 0.07), and no difference was found between MT vs. MRT (p = 0.69).
  • A higher proportion of recipients of tailored materials reported reading all of the materials and believing that they were written especially for them.
  • No differences by experimental condition were found for the perceived usefulness or motivational impact of the print materials.
  • Retailoring did not produce a significant difference when compared with longitudinal baseline tailoring.

Conclusion +

The majority of CIS callers endorsed the strategy of providing 5 A Day information at the end of usual service, even if such information was not specifically requested by the caller (i.e., the information was provided to CIS callers proactively).

MT print materials were more effective at increasing fruit and vegetable (FV) consumption than were SU materials. The intervention mechanisms responsible for this effect merit further research.