A process and mechanism of action evaluation of the effect of early and intensive nutrition care, delivered via telephone or mobile application, on quality of life in people with upper gastrointestinal cancer: a study protocol.

BACKGROUND Cancers of the upper gastrointestinal tract commonly result in malnutrition, which increases morbidity and mortality. Current nutrition best practice lacks a mechanism to provide early and intensive nutrition support to these patients. A 3-arm parallel randomised controlled trial is testing the provision of a tailored, nutritional counselling intervention delivered using a synchronous, telephone-based approach or an asynchronous, mobile application-based approach to address this problem. This protocol outlines the design and methods that will be used to undertake an evaluation of the implementation process, which is imperative for successful replication and dissemination. METHODS A concurrent triangulation mixed methods comparative analysis will be undertaken. The nutrition intervention will be provided using best practice behaviour change techniques and communicated either via telephone or via mHealth. The implementation outcomes that will be measured are: fidelity to the nutrition intervention protocol and to the delivery approach; engagement; acceptability and contextual factors. Qualitative data from recorded telephone consultations and written messages will be analysed through a coding matrix against the behaviour change techniques outlined in the standard operating procedure, and also thematically to determine barriers and enablers. Negative binomial regression will be used to test for predictive relationships between intervention components with health-related quality of life and nutrition outcomes. Post-intervention interviews with participants and health professionals will be thematically analysed to determine the acceptability of delivery approaches. NVivo 11 Pro software will be used to code for thematic analysis. STATA version 15 will be used to perform quantitative analysis. DISCUSSION The findings of this process evaluation will provide evidence of the core active ingredients that enable the implementation of best practice nutrition intervention for people with upper gastrointestinal cancer. Elucidation of the causal pathways of successful implementation and the important relationship to contextual delivery are anticipated. With this information, a strategy for sustained implementation across broader settings will be developed which impact the quality of life and nutritional status of individuals with upper gastrointestinal cancer. TRIAL REGISTRATION 27th January 2017 Australian and New Zealand Clinical Trial Registry ( ACTRN12617000152325 ).