Theory of planned behaviour-based interventions in chronic diseases among low health-literacy population: protocol for a systematic review

Background: Health behaviour can change outcomes in both healthy and unhealthy populations and are particularly useful in promoting compliance to treatment and maintaining fidelity to care seeking and follow-up options in chronic diseases. Interventions to change health behaviour based on psychological theory are more often successful than those without any underlying theory. The theory of planned behaviour (TPB) is one such psychological theory which had been found to predict human behaviour with respect to disease prevention and when applied to interventions can change the outcomes of diseases. Most of the research evidence of TPB-based interventions have been from developed world. Evidence is required whether TPB-based interventions can be applied and works in low-resource, low health-literacy settings of low- and middle-income countries (LMICs). Methods: The protocol has been developed as per PRISMA-P guidelines and incorporates PICO (population, intervention, comparison, outcomes) framework for describing the methodology. Population above 18 years of age and having any chronic disease (as defined for this systematic review) will be selected, while any health or educational intervention based on constructs of TPB will be included. Comparison will be with non-TPB-based interventions or treatment as usual without any intervention, and the primary outcome will be the behaviour change effected by the TPB-based intervention. Intervention studies will be considered, and relevant databases like MEDLINE, Embase, Cochrane Library and ProQuest will be explored. Data extraction will done in a standardised form, and risk-of-bias assessment will be done using the Cochrane Collaboration’s tools for such assessment. Narrative synthesis of the selected studies will be done to draw the conclusions, and meta-analysis will be done to calculate the effect estimates with I-squared statistics to describe the heterogeneity. Discussion: This systematic review will provide new evidence on fidelity and effectiveness of the TPB-based interventions among chronic disease patients from low health literacy, resource-poor background. It will inform of how to plan and use such interventions to change health behaviour in chronic disease patients, particularly in LMIC settings. Systematic review registration: PROSPERO CRD42018104890.