To determine the validity of a summary infant and child feeding index (ICFI) and the association with the index of factors related to agricultural production.

A cross-sectional survey in eight health-post jurisdictions identified as priority nutrition regions. All households with children aged 6–23 months in eligible communities were administered an integrated survey on agricultural production and nutrition-related practices. Quantitative 24 h dietary recall, food frequency data and anthropometric measurements were collected for each child. Ninety-one per cent of eligible families participated.

The northern region of the Potosí department in the Bolivian highlands.

Two hundred and fifty-one households with children aged 6–23 months.

In multiple regression models controlling for potential confounding variables, infant and young child feeding (IYCF) practices as measured by an ICFI showed positive associations with child length-for-age Z-score (mean difference of 0·47 in length-for-age Z-score between children in the high ICFI tertile compared with the low tertile), child energy intake (mean difference of 1500 kJ between tertiles) and the micronutrient adequacy of child diets (mean difference of 7·2 % in mean micronutrient density adequacy between tertiles; P < 0·05). Examining determinants of IYCF practices, mother's education, livestock ownership and the crop diversity of farms were positively associated with the ICFI, while amount of agricultural land cultivated was negatively associated with the ICFI. Crop diversity and IYCF practices were more strongly positively correlated among households at high elevations.

Nutrition-sensitive investments in agriculture that aim to diversify subsistence agricultural production could plausibly benefit the adequacy of child diets.