Salt sales survey: a simplified, cost-effective method to evaluate population salt reduction programs--a...

Area of Science:

• Public Health
• Nutritional Epidemiology
• Health Services Research

Background:

• Traditional 24-hour urine collection for salt intake assessment is resource-intensive, limiting its application in large-scale public health initiatives.
• Effective monitoring tools are crucial for evaluating the success of population-wide salt reduction strategies.

Purpose of the Study:

• To investigate the feasibility and effectiveness of a salt sales survey as an alternative to 24-hour urine collection for assessing salt intake.
• To compare the cost-effectiveness and statistical power of salt sales surveys versus traditional urine collection methods in a community intervention setting.

Main Methods:

• A substudy of the China Rural Health Initiative-Sodium Reduction Study (CRHI-SRS) involving 120 villages allocated to price subsidy+health education, health education only, or control groups.
• Monthly salt sales data were collected from 166 shops in 30 selected villages.
• Comparison of salt sales data with 24-hour urine sodium and potassium excretion data from 2567 adults.

Main Results:

• Mean monthly salt substitute sales per shop significantly differed across intervention groups (PS+HE: 38.0 kg, HE only: 19.2 kg, Control: 2.2 kg; P<0.05).
• Intervention effect estimates for sodium and potassium intake from salt sales surveys were 101% and 114% of those from 24-hour urine data, respectively.
• The salt sales survey was 86% less costly than the 24-hour urine method and demonstrated greater statistical power.

Conclusions:

• A salt sales survey is a simple, sensitive, and cost-effective method for evaluating community-based salt reduction programs.
• This method is particularly suitable for interventions where consumers primarily add salt themselves.