Adaptation of the Diet Quality Questionnaire as a Global Public Good for Use in 140 Countries

Background: Food group consumption data are useful for measuring and monitoring diet quality. To collect valid data across contexts, consistent and rigorous adaptation of survey questions is needed. Objectives: The objective of this research was to adapt food group consumption survey questions for 140 countries, by identifying the most common (sentinel) food items in each food group using a structured, participatory process and global standards for classification. Methods: Survey questions were adapted for 29 food groups of the Diet Quality Questionnaire (DQQ) and for additional questions for infant and young child feeding (IYCF) indicators. For each country, adaptation comprised the following: 1) review of existing questionnaires, dietary intake data, and other information to draft food lists; 2) key informant (KI) interviews with 5–12 experts to identify and prioritize sentinel items including terminology; 3) comparison of items across countries within the same region to identify inconsistencies, and follow-up with KIs to resolve them. Results: In total, 1016 KIs contributed to the adapted DQQs for 140 countries and IYCF DQQs for 96 countries, amounting to ∼9550 h of collective effort (68 person-hours/country on average) from 2020 to 2024. The process revealed numerous challenges and decisions to ensure consistent classification of items and valid question formulation. Conclusions: Country-specific questions adhering to global standards, and adapted through cumulative and iterative input of local experts, enable the collection of food group consumption data that are valid and comparable across time and geographies. The adapted survey questions have been implemented in the Demographic and Health Surveys and Gallup World Poll in 94 countries, generating the first cross-country data on Minimum Dietary Diversity and other diet quality indicators. The finalized country-adapted DQQs and IYCF DQQs were translated to 143 national languages and are published online as a global public good for population-level diet quality measurement.