Evaluating Implementation and Scale-Up of Nigeria's National Sodium Reduction Program

The Nigerian Agency for Food and Drug Administration and Control (NAFDAC) is leading implementation and scale-up of a national sodium reduction program with other national, state, and international agencies using the WHO's "Best Buy" SHAKE package (Surveillance of salt intake, Harness industry, Adopt standards for labelling and marketing, Knowledge to empower consumers, and Environments to promote healthy eating). SHAKE provides evidence-based recommendations for population-wide sodium reduction interventions for hypertension prevention and control.

The Nigeria Sodium Study will support this program's implementation and scale-up by evaluating the extent to which the program is implemented using a type III hybrid, mixed methods study design through repeated: 1) stakeholder interviews, 2) populations surveys, and 3) retail surveys. Implementation research methods will be used during adaptation, planning, and initial implementation for baseline (Wave 1) and follow-up Waves 2 and 3) assessments. A dietary sources of sodium study will also be performed at baseline and Wave 3 follow-up to target/track sodium reduction efforts according to local context and culture. Food retail surveys over the study period will capture novel data on packaged, unpackaged, and informal restaurant/hawker food through the international FoodSwitch program, which combines a consumer facing tool with crowdsourcing to better define Nigeria's food supply.

Investigators will use the Exploration, Preparation, Implementation and Sustainment (EPIS) framework throughout both phases. The formative research period will include Exploration and Preparation, when investigators will perform quantitative and qualitative measures of key process indicators, relevant contextual factors informed by CFIR, and relevant Proctor implementation outcomes, acceptability, feasibility and appropriateness. As implementation is started, investigators will use the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework, including implementation outcomes (feasibility, fidelity, adoption, acceptability, and cost) and contextual factors associated with the Implementation and Sustainment phases.

• Change in overall and relative amount of dietary sources of sodium from baseline (Wave 1) to follow-up (Wave 3) [Time frame: Baseline (Wave 1) to follow-up (Wave 3 [estimated 36 months post-baseline)]
• Changes in self-reported knowledge, attitudes, and behavior about harms associated with excess sodium intake from baseline (Wave 1) to follow-up (Wave 3) [Time frame: Baseline (Wave 1) to follow-up (Wave 3 [estimated 36 months post-baseline)]