BACKGROUND: Sub-optimal physical growth has been suggested as a key pathway between the effect of environmental risk and developmental outcome.

AIM: To determine if anthropometric status mediates the relation between socioeconomic status and psychomotor development of young children in resource-limited settings.

STUDY DESIGN: A cross-sectional study design was used.

SUBJECTS: A total of 204 (105 girls) children from two resource-limited communities in the Coast Province, Kenya. The mean age of these children was 29 months (SD = 3.43; range: 24-35 months).

OUTCOME MEASURE: Psychomotor functioning was assessed using a locally developed and validated measure, the Kilifi Developmental Inventory.

RESULTS: A significant association was found between anthropometric status (as measured by weight-for-age, height-for-age, mid-upper arm circumference, and head circumference) and psychomotor functioning and also between socioeconomic status and anthropometric status; no direct effects were found between socioeconomic status and developmental outcome. The models showed that weight, height and to a lesser extent mid-upper arm circumference mediate the relation between socioeconomic status and developmental outcome, while head circumference did not show the same effect.

CONCLUSION: Among children under 3 years living in poverty, anthropometric status shows a clear association with psychomotor development while socioeconomic status may only have an indirect association.