About the database
The Global Database is a standardized compilation of child growth and malnutrition data from nutritional surveys conducted around the world since 1960. Scientists have been using growth assessment because it best defines the health and nutritional status of children while serving as a useful indirect measurement of a population's overall socioeconomic status. These were among the basic underlying assumptions leading to the establishment, in 1986, of the World Health Organization's global surveillance system for monitoring patterns and trends in child growth and malnutrition.
The Global Database includes population-based surveys that fulfil a set of criteria. Data are checked for validity and consistency and raw data sets are analysed following a standard procedure to obtain comparable results. Prevalences below and above defined cut-off points for weight-for-age, height-for-age, weight-for-height and body mass index (BMI)-for-age, in preschool children are presented using z-scores based on the WHO Child Growth Standards. New surveys are included on a continuous basis and updates are published quarterly on this website. A detailed description of the methodology and procedures of the database including data sources, criteria for inclusion, data quality control and database work-flow, are described in a paper published in 2003 in the International Journal of Epidemiology.
The WHO Child Growth Standards, launched on April 2006, replace the NCHS/WHO international reference for the analysis of nutritional surveys. Their use has been officially endorsed by the International Pediatric Association (IPA), the Standing Committee on Nutrition of the United Nations System (SCN), and the International Union of Nutritional Sciences (IUNS), as an effective tool for detecting and monitoring both undernutrition and overweight, thus addressing the double burden of malnutrition affecting populations on a global basis.
Differences between the WHO standards and the NCHS reference are substantial, especially during infancy, and vary by age group, growth indicator, specific percentile or z-score curve, and the nutritional status of the index population (see link to paper in the Public Health Nutrition Journal below).
Detailed information on the WHO standards is available at the website:
For historical reasons, the "old" Global Database (i.e. based on the NCHS/WHO international reference) remains available with the country data and references collected up to 2006. Nutritional surveys with available raw data are being re-analysed using the WHO Child Growth Standards for inclusion in this new Global Database. Researchers are encouraged to re-submit their data to the Global Database using the WHO Standards as a basis for comparison. Overall national survey estimates for which raw data were unavailable have been converted to be WHO-standards based using the recommended algorithms (see link to paper below); these converted estimates are clearly marked as "converted" in the NOTES column.
To facilitate re-running of nutritional survey data, WHO recommends using either the new software WHO Anthro or the statistical macros. Both can be downloaded together with manuals and Readme files from the link below.
- The WHO Anthro software module "Nutritional survey" enables analysis of existing data sets.
- The macros are available for SPSS, SAS, STATA and S-Plus. They are particularly recommended for analysis of large survey data sets.
Both the software and the macros allow the user to produce result tables in the format of the standard data-entry form ready for submission to the Global Database.