Collections > Electronic Theses and Dissertations > Information processes of health communication and fruit and vegetable consumption: a multi-sample structural equation modeling approach by intervention and colon cancer status groups
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A diet low in fruits and vegetables has been associated with increased risk for colorectal cancer. Health communications with Tailored Print Communication (TPC) and Telephone Motivational Interviewing (TMI) have been shown to be effective in promoting fruits and vegetable consumption (FVC). This study explored the mechanisms underlying TPC and TMI effectiveness among colon cancer survivors and colon cancer-free individuals, guided by the Information Processing Theory. The data come from the North Carolina Strategies to Improve Diet, Exercise, and Screening study (NC STRIDES). NC STRIDES tested the efficacy of TPC and TMI to promote FVC among a population-based sample of 735 participants (36% colon cancer survivors and 64% colon cancer-free individuals) who were randomized to control, TPC, TMI, or combined (TPC+TMI) groups. Information processes were perception of message relevance, trust, and recall. Multi-sample structural equation models were constructed. Among colon cancer survivors, the relationship between health communication and FVC was mediated by information processes but only in those who received the TPC+TMI. The model fit resulted in x2(27, N =266) =31.52, CFI =.99, TLI =.99, RMSEA =.025, and SRMR =.027. Receiving a combination of TPC+TMI was associated with perception of message relevance (p =.05). Greater relevance was associated with trust (p <.001), and higher trust was related to FVC (p <.05). In the colon cancer-free group, the relationship between health communication and FVC was mediated by information processes among those who received the TMI intervention only and TPC+TMI. The model had a good fit with x2(28, N =469) =68.11, CFI =.98, TLI =.97, RMSEA =.055, and SRMR =.036. TMI had an indirect effect on FVC through message relevance. TPC+TMI influenced FVC through two paths. In the first path, message relevance was associated with trust (p <.001) and greater trust was related to recall (p <.05). More recall influenced FVC (p <.05). In the second path, message relevance was associated with recall (p <.001), and more recall with FVC (p <.05). Given the significant finding that information processes mediate the relationship between health communication and FVC, a promising direction for developing interventions would be to enhance information processes in future interventions.