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Related Experiment Video

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Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity

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How Does Survey Timing Influence Apparent Wasting Trends? A Case Study from Senegal.

Karan S Shakya¹, Leah Bevis¹, Rebecca A Heidkamp²

¹Department of Agricultural, Environmental and Development Economics, Ohio State University, Columbus, OH.

Current Developments in Nutrition

|April 17, 2026

Summary

Child wasting shows seasonal patterns that can bias multiyear trend analysis. Conducting surveys at the same time each year is crucial for accurate tracking of child wasting prevalence.

Keywords:

Senegal progress sustainable development goals tracking wasting

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Published on: May 8, 2020

Area of Science:

Global Health
Pediatrics
Nutritional Epidemiology

Background:

Child wasting is recognized to have seasonal variations.
Few studies have investigated the impact of wasting seasonality on multiyear trend assessments.

Purpose of the Study:

To examine the seasonality of child wasting in Senegal in relation to multiyear changes.
To assess the implications of seasonality for tracking wasting trends.
To test if month-fixed effects can reduce bias in estimating long-term wasting trends.

Main Methods:

Calculated average child wasting prevalence (weight-for-height z-score < -2) by month and year (2012-2019) using Demographic and Health Surveys (DHS) data.
Defined peak and low wasting seasons based on the 4 highest and 4 lowest months of average prevalence.
Generated month-adjusted annual wasting estimates using month-fixed effects linear regression and evaluated bias adjustment in simulations.

Main Results:

Nationally, wasting prevalence fluctuated between 2013-2019, with a low of 6.0% in 2014 and a high of 9.0% in 2017.
Peak season prevalence was 8.8%, while low season prevalence was 6.4%.
Month-adjusted estimates showed minimal difference from raw prevalence; simulations indicated bias reduction only when survey timing differences were minimal (1-2 months).

Conclusions:

Significant seasonal fluctuations in child wasting can distort multiyear trend interpretations.
Standardizing national survey timing to the same period annually is recommended.
Seasonality adjustment via month-fixed effects is most reliable with minimal survey timing variations across data collection waves.