Behaviour Change Interventions Improve Maternal and Child Nutrition in Sub-Saharan Africa: A Systematic Review

"Improving nutritional outcomes requires behaviour change."

Research suggests that, to improve maternal and child nutrition, interventions must combine behaviour change with access to nutritious food. Behavioural scientists and health psychologists argue that those designing behaviour change interventions should engage with the intended population, understand their motivation to change, and adapt interventions to the contexts that facilitate change, including environment and social networks. One model used to inform such work is the Behaviour Change Wheel, which outlines nine behavioural intervention functions that aim to address deficits in one or more of the three underlying human factors: Capability (physical and psychological), Opportunity (physical and social), and Motivation (automatic and reflective) that influence Behaviour (COM-B model). This systematic review seeks to answer the following questions: (i) are behaviour change nutrition interventions effective in improving maternal and child nutrition in sub-Saharan Africa? (ii) which functions of behaviour change interventions are associated with improvements in maternal and child nutrition outcomes?

Six databases were searched systematically, using MeSH and free-text terms, for articles describing nutrition-specific and nutrition-sensitive behaviour change interventions published in English until November 2022. Data extraction and quality assessments followed Centre for Reviews and Dissemination guidelines. Behaviour change functions of interventions were mapped onto the COM-B model and Behaviour Change Wheel. The search yielded 1,193 articles: 79 articles met inclusion criteria, ranging from low (n = 30) to high (n = 11) risk of bias (RoB). The 79 articles were published between 2004-2022 and included cluster randomised control trials (RCTs) (n = 38), quantitative studies (n = 17), study evaluations (n = 13), mixed-methods studies (n = 5), qualitative studies (n = 4), and national case studies (n = 2). Behaviour change interventions were identified from 18 sub-Saharan African countries.

Results are presented as a narrative synthesis and based on the intervention's quality assessment and direction of effect in relation to research question (i). Each finding from a study reports the RoB score and direction of effect in brackets to accompany the description. The Strength of Recommendation Taxonomy (SORT) was used to appraise the overall quality, quantity, and consistency of evidence and provide a grading for the recommendations of this review. Tables 3 and 4 in the paper report the descriptions of each paper, the RoB score (ranging from low (n = 30) to high (n = 11) RoB), and the direction effect according to the hypothesis.

Overall, there was evidence showing that behaviour change nutrition interventions have an effect on anthropometric markers such as height and weight. Nineteen out of the 25 studies favoured the intervention (76% [57%, 89%], p = 0.015); 16 out of the 25 studies were of low RoB. Out of these, 13 favoured the intervention. For example, a mother and child lipid supplementation RCT combined with maternal nutrition counselling in Madagascar reported an increase in infants' length-for-age z-scores (LAZ) of 0.210-0.216 standard deviation (SD), and stunting reduced by 8.2-9.0% compared to the control. And interventions that provided food rations or vouchers and behaviour change communication to mothers in Burundi and Ethiopia showed reduced prevalence of child stunting in the intervention compared to the control arm.

Many that applied behaviour change theory, communication, or counselling resulted in significant improvements in infant stunting and wasting, household dietary intake, and maternal psychosocial measures. For instance, there was evidence that behaviour change nutrition interventions influence dietary outcomes, with 34 out of 46 studies favouring the intervention (74% [60%, 84%], p = 0.002). Twenty-three studies were judged to be at a low RoB, and 18 of these favoured the intervention. On the other hand, there is little evidence that these interventions improved maternal and infant nutrient intake. This could be because changes in nutrient intake were not often measured due to a lack of comprehensive data on the nutrient composition of foods.

Interventions were coded on the basis of involving one or more Behaviour Change Wheel intervention functions, including education (n = 56), enablement (n = 56), persuasion (n = 46), training (n = 39), modelling (n = 39), environmental restructuring (n = 17), and incentivisation (n = 11). There were no interventions that included restriction or coercion. Table 5 indicates that in interventions where the Behaviour Change Wheel intervention functions persuasion, environmental restructuring, and incentivisation were used, body composition and diet intake improved. All are hypothesised to change motivations. For example, in one intervention that included persuasive communication, grandmothers were encouraged through nutrition education to promote improved nutritional practices related to pregnancy and infant feeding within their families. This intervention was delivered through songs, storytelling, and group discussions and made an emotional appeal to grandmothers' intrinsic commitment to family well-being. These persuasive communications were therefore explicitly designed to induce an emotional response (automatic motivation), as well as to educate and inform (reflective motivation).

Table 6 in the paper describes the way in which people's capability, opportunity, and motivation are addressed in interventions to improve maternal and child nutrition and health outcomes. For example, food demonstrations and provision of agricultural land address physical capability and opportunity components, respectively, as specified by the COM-B model as necessary to change behaviour. The COM-B model suggests that not addressing participant's motivation reduces the effectiveness of behaviour change interventions. The analysis in Table 6 demonstrates that nutrition-specific and nutrition-sensitive interventions cannot alone address motivation and require additional behaviour change functions in order to address behaviours that improve maternal and child nutrition and health outcomes.

In conclusion, this review has explained why nutrition-specific interventions, such as increasing access to food, and nutrition-sensitive interventions, such as offering cash transfers, are not always enough to improve nutritional status of women and children in sub-Saharan Africa. Behaviour change communication and counselling are also unlikely on their own to be effective because they do not address food insecurity or nutritional deficiencies in high-poverty contexts. Thus, the researchers recommend incorporating behaviour change functions in nutrition interventions to improve maternal and child outcomes, specifically drawing on the Behaviour Change Wheel, COM-B model.

Going forward: "To enhance the designs of these interventions, and ultimately improve the nutritional and psychosocial outcomes for mothers and infants in this region, multidisciplinary collaborations are required....[A] recommendation would be to task behaviour change and nutrition experts such as health psychologists and nutritionists, as well as intervention designers, policy makers, and commissioners of services to fund and roll out these multicomponent behaviour change interventions."