Information processes mediate the effect of a health communication intervention on fruit and vegetable consumption

Abstract

Health communication interventions have been effective in promoting fruit and vegetable consumption (FVC). To explore mechanisms underlying health communication effectiveness, the authors investigated whether information processes mediated the relationship between health communication and FVC, using data from NC STRIDES. NC STRIDES tested the efficacy of two health communication strategies to promote FVC among a diverse population-based sample of older adults. Participants were randomized to 1 of 4 groups: control, tailored print communication (TPC), telephone motivational interviewing (TMI), or combined (TPC + TMI). To analyze data from 469 participants, the authors constructed multi-sample structural equation models. Information processes mediated the effect of TMI and TPC + TMI on FVC. TMI had an indirect effect on FVC through relevance of the communications. TPC + TMI influenced FVC through perceived relevance of the communications, trust in the communications, and dose recall via two paths. In the first path, relevance was associated with trust. Trust was associated with recall, and greater recall predicted FVC. In the second path, relevance was associated with dose recall, and more recall predicted FVC. Thus, the authors found that key information processes mediated the relationship between a health communication intervention and FVC. Further research should investigate ways to enhance relevance, trust, and recall during the delivery of interventions.

Figure 1

Conceptual model depicting the relationship between intervention, information processes, and fruit and vegetable consumption. TPC = tailored print communication, TMI = telephone motivational interviewing, TPC+TMI = tailored print communication + telephone motivational interviewing. FVC = fruit and vegetable consumption.

Figure 2

Path diagram of model testing direct relationship between intervention and fruit and vegetable consumption, adjusting for baseline fruit and vegetable consumption. Unstandardized β weights for variables entered into the model are shown. Significant relationships are indicated by asterisks (*p < .05, **p < .001).

Figure 3

Path diagram of model testing information processes as mediators of the association between intervention and fruit and vegetable consumption, adjusting for baseline fruit and vegetable consumption. Unstandardized β weights for variables entered into the model are shown. Significant relationships are indicated by asterisks (*p < .05, **p < .001).

Figure 4

Path diagram of multi-sample structural equation model by intervention groups. Unstandardized β weights for variables entered into the model are shown. The solid arrow indicates significant equal paths, the dashed arrow significant different paths. Significant relationships are indicated by asterisks (*p < .05). FVC = fruit and vegetable consumption.