Process evaluation of Samoa’s national salt reduction strategy (MASIMA): what interventions can be successfully replicated in lower-income countries?

Abstract

BackgroundEvidence for recommended interventions to reduce population salt intake come from high-income countries, but it is unknown if these can be successfully replicated in low- and middle-income countries. This process evaluation investigated the reach, dose/adoption, fidelity, cost, and context of a national salt reduction program of interventions in Samoa.MethodsMonitoring and Action on Salt in Samoa (MASIMA) was a pre- and post-intervention study of a government-led strategy to lower population salt intake comprising awareness campaigns, community mobilization and policy and environmental changes. Data relating to the five process evaluation dimensions were collected from routinely collected data, a post-intervention survey and stakeholder interviews. Chi-squared tests assessed differences in quantitative survey responses among groups. Thematic analysis of qualitative interview responses was undertaken and triangulated with the quantitative data.ResultsAwareness campaigns, school nutrition standards, and community mobilization interventions were implemented with moderate reach and fidelity. Higher than expected costs of campaigns and limited opportunity (one-off) to mobilize community leaders to disseminate salt reduction messages were key implementation challenges, which meant intervention dose was low. Environmental-level initiatives including engagement with the food industry to voluntary reduce salt in foods and the introduction of salt-related regulations were more challenging to implement within 18-months, particularly given the delay in the passing of the Food Act which provides for enforcement of regulations. Contextual factors that hindered the interventions’ mechanism of effect include the food culture, higher cost, and lower availability of healthy low-salt foods relative to unhealthy foods and salty taste preference.ConclusionAlthough individual and community-based interventions helped increase awareness about the importance of salt reduction in Samoa, legislative backing was needed to alter the food environment to achieve population reduction in salt intake. It was not possible to engage the food industry to lower salt in foods through a voluntary approach in Samoa’s current context, although such initiatives were successful in some high-income countries. Future individual and environmental-level interventions to reduce salt intake need to address the contextual influences of food choices. In Samoa, this means salt reduction strategies need to ensure consuming lower salt is affordable, widely available, and perceived as flavorsome.Electronic supplementary materialThe online version of this article (10.1186/s13012-018-0802-1) contains supplementary material, which is available to authorized users.

Strengthening and measuring research impact in global health: lessons from applying the FAIT framework

“…We chose these projects because good documentation was available from which data could be extracted. For the Pacific Salt project, there was a study protocol, process evaluations, impact evaluations and intervention costings for each Pacific country [38, 39]. For SMART health, an end-of-project completion report had been prepared for the funder, which included clinical results and a cost-effectiveness analysis.…”

The role of contextualisation in enhancing non-communicable disease programmes and policy implementation to achieve health for all

“…In Samoa, 'best buy' interventions, such as engagement with food manufacturers in voluntary product reformulation to contain less sodium, were not well accepted by government and the food industry. Another intervention, front-of-pack nutrition labelling, was not feasible to implement within the existing regulatory frameworks at the time [6]. Behaviour change communication and the establishment of supportive communities were more feasible.…”

“…This gap between research evidence and policy effectiveness was illustrated when the sodium reduction 'best buys' were implemented in Samoa (2013-2015), a vastly different context to the countries where the evidence of effective strategies originated (e.g. United Kingdom, Finland), and where null effects on population-level dietary sodium consumption were observed following programme implementation [6]. In Samoa, 'best buy' interventions, such as engagement with food manufacturers in voluntary product reformulation to contain less sodium, were not well accepted by government and the food industry.…”

“…From the perspective of Story et al's ecological framework [7], which incorporates multi-level influences on what people consume, only individual and socioenvironmental factors were targeted in Samoa, and physical and macro-level environmental factors were insufficiently addressed. Furthermore, unlike diets in the United Kingdom or Finland, where most (>75%) dietary sodium intake came from processed or packaged foods, or diets in China, where 75% of dietary sodium intake came from salt added during cooking, diets in Samoa included both salt added by consumers and sodium added by manufacturers in processed foods as similar and major contributors [6]. This context meant that a multi-component strategy effectively targeting both consumers and food manufacturers was needed in Samoa.…”

Systematic Reduction of Excessive Salt Intake

“…Recent systematic review of salt reduction interventions by Hyseni et al [24] introduced 'effectiveness hierarchy' of interventions (Figure 1) that suggested the biggest reductions in salt consumption in the population could be achieved by comprehensive strategies involving 'upstream' population-wide policies (regulation, mandatory reformulation and food labelling). This is particularly emphasized in middle-to-low income countries, as this is the only way to successfully change the food environment and thereby achieve a reduced salt intake in the population [25,26]. 'Downstream' individually-based interventions appeared relatively weak Interventions classified on the upstream/downstream continuum; adapted from [24].…”