Health and nutritional information for many countries in the South-East Asian region is either lacking or no longer up to date. The present study aimed to calculate length/height percentile values for the South-East Asian Nutrition Survey (SEANUTS) populations aged 0·5–12 years, examine the appropriateness of pooling SEANUTS data for calculating common length/height percentile values for all SEANUTS countries and whether these values differ from the WHO growth references.

Data on length/height-for-age percentile values were collected. The LMS method was used for calculating smoothened percentile values. Standardized site effects (SSE) were used for identifying large or unacceptable differences (i.e. $\mid\! \rm SSE \!\mid$ >0·5) between the pooled SEANUTS sample (including all countries) and the remaining pooled SEANUTS samples (including three countries) after weighting sample sizes and excluding one single country each time, as well as with WHO growth references.

Malaysia, Thailand, Vietnam and Indonesia.

Data from 14202 eligible children were used.

From pair-wise comparisons of percentile values between the pooled SEANUTS sample and the remaining pooled SEANUTS samples, the vast majority of differences were acceptable (i.e. $\mid\! \rm SSE \!\mid$ ≤0·5). In contrast, pair-wise comparisons of percentile values between the pooled SEANUTS sample and WHO revealed large differences.

The current study calculated length/height percentile values for South East Asian children aged 0·5–12 years and supported the appropriateness of using pooled SEANUTS length/height percentile values for assessing children’s growth instead of country-specific ones. Pooled SEANUTS percentile values were found to differ from the WHO growth references and therefore this should be kept in mind when using WHO growth curves to assess length/height in these populations.