Project Overview +

Eat for Life examines two constructs of tailoring within a print-based fruit and vegetable intervention for African American adults. Study 1 explores the use of motivational predisposition to tailor health behavior content, while Study 2 explores the use of cultural factors and ethnic identity for tailoring its' messages. Both studies use tailored print media, in the form of three 8 to 12 page newsletters, delivered to participants' homes.

Aims +

Phase I:

Aim 1. Develop conceptually distinct intervention messages for modifying fruit and vegetable intake for African Americans, from domains of cultural tailoring (surface structure, deep structure, and culturally-based) and domains of motivation (extrinsic, intrinsic, and values-based).

Aim 2. Using a fractional factorial design, identify the most powerful messages and/or combination of messages that impact fruit and vegetable intake at six month follow-up.

Aim 3. Identify person characteristics that modify the impact of these messages (e.g., ethnic identity and motivational predisposition).

Phase II:

Aim 1. Develop an individually-tailored, print fruit and vegetable intervention using conceptually distinct cultural and motivational messages.

Aim 2. Explore the optimal "dose" of tailored cultural and motivational messages.

Aim 3. Explore the optimal "source" the tailored messages, such as peer, professional, or religious leader.

Aim 4. Explore possible person characteristics that may interact with message, dose and source factors.

Participants +

1,600 African Americans in 3 Cancer Research Network HMOs.

Intervention +

Phase I

The initial phase of Eat for Life creates elements that help build both the motivational disposition and culture/ethnic identity interventions delivered during Phase II.

  • Creation of The Black Identity Classification Scale (BICS). BICS assigns each participant one of 16 Ethnic Identity types. The BICS is comprised of new items as well as items culled from prior measures (e.g., Cross Racial Identity Scale, Multidimensional Inventory of Black Identity, and the Survey of Black Life). The BICS was pre-tested using focus groups, telephone pretests, and a pilot study (n=306). Findings suggest that the BICS has good psychometric properties and may be an effective tool for identifying African American audience segments.
  • Development of an image library of photos (over 2,000 images) and drawings, most which depict Black Americans doing a variety of healthy activities. Image libraries typically have few images of Black Americans living active, healthy lives. This visual library allows more uniquely tailored newsletters, because the images show many age groups for both genders, and include cultural variation in a person's appearance as well as background scenes.
  • Analyses of focus groups to pre-test ethnic identity specific messages, images, and newsletter designs.
  • Development of conceptually distinct intervention messages for modifying fruit and vegetable intake for Black Americans, derived from either a) domains of cultural tailoring: surface structure, deep structure, and culturally-based; or b) domains of motivation: extrinsic, intrinsic, and values-based.

Phase II

For both studies, African American adults are recruited from two integrated healthcare delivery systems, one based in the Detroit Metro area and the other in the Atlanta Metro area. Participants are randomized to receive three newsletters focused on fruit and vegetable intake behavior change.

  • One set of newsletters is tailored only on demographic, behavioral, and social cognitive variables (control condition) whereas the other two sets of newsletters (both experimental conditions) were ALSO tailored on either Motivational Predisposition or Ethnic Identity.
  • The three newsletters are delivered approximately once a month over three months. Each newsletter includes two recipe cards with small bags of spices that corresponded to the recipes along with a magnetized refrigerator notepad or a magnet with fruit and vegetable serving size information.
  • The primary outcome for the study is fruit and vegetable intake, assessed during telephone interviews at baseline and three months later.

Findings +

Motivational Predisposition Study:

A total of 512 people were enrolled, of which 423 provided complete 3-month follow-up data. There were no significant between-group differences in daily fruit and vegetable intake at follow-up. Both groups showed similar increases at 3-month follow-up of around 1 serving per day of fruit and vegetables on the short form and half a serving per day on the long form. There were however, significant interactions of intervention group with preference for autonomy supportive communication as well as with age.

Specifically, individuals in the experimental intervention who at baseline preferred an autonomy supportive style of communication increased their fruit and vegetable intake by 1.07 servings compared to 0.43 servings among controls. Among younger controls there was a larger change in fruit and vegetable intake, .59 servings, than their experimental group counterparts, .29 servings. Conversely, older experimental group participants showed a larger change in fruit and vegetables, 1.09 servings, than older controls, .48.

Ethnic Identity Study:

A total of 560 eligible participants were enrolled, of which 468 provided complete 3-month follow-up data. The experimental group increased their daily mean F & V intake by 1.1 servings compared to .8 servings in the control group. This difference was not statistically significant (p = .13). However, several variables were found to interact with intervention group. Experimental group participants classified as Afrocentric showed a 1.4 increase in F & V servings per day compared to a .43 servings per day increase among Afrocentric controls. This difference was significant (p < .05). And, among participants characterized as both Afrocentric and Cultural Mistrust, F & V increased 1.3 servings in the experimental group compared to a decrease of .7 servings in the control group (p = .07). Further, among experimental participants there was a significant association between the amount of newsletters read and perceived personal relevance (p = .01).

Interviewer Study (Sub-Study of EFL EI):

We used data from two telephone-administered health surveys to explore African Americans’ preferences for interviewer race. The first survey utilized African American interviewers to assess ethnic identity and aspects of healthy eating among 617 African American adults. In the second survey, interviewers of varying races queried 534 African American adults about their motivations to eat healthier. The motivation survey contained almost no racial content, whereas 40% of the ethnic identity survey assessed racial content. Using ethnic identity survey data only, we found that respondents with Afrocentric or Black American identity components were more likely to prefer African American interviewers than respondents with solely Assimilated, Bicultural, or Multicultural identity components. Ethnic identity survey respondents were also more likely to prefer racially/ethnically matched interviewers than motivation survey respondents. Ethnic identity respondents with a college or graduate degree reported lower hypothetical comfort with a White interviewer than respondents with a high school education.

Conclusion +

Motivational Predisposition Study

Our study confirms the importance of assessing individual differences as potential moderators of tailored health interventions. For those who prefer an autonomy supportive style of communication, tailoring on values and other motivational constructs can enhance message impact and perceived relevance.

Ethnic Identity Study

Tailoring dietary messages on African American Ethnic Identity can improve intervention impact at least for some EI types.