The Household Dietary Diversity Score (HDDS) was developed in 2006 as part of the FANTA II project as an indicator of household food access. Household dietary diversity can be described as the number of food groups consumed by a household over a given reference period, and is an important indicator of food security for many reasons. A more diversified household diet is correlated with caloric and protein adequacy, percentage of protein from animal sources, and household income (Swindale et al. 2006). The HDDS indicator provides a glimpse of a household’s ability to access food as well as its socioeconomic status (Kennedy et al. 2011).
Method of Construction
The following 12 food groups are used to calculate the HDDS indicator:
B. Root and tubers
E. Meat, poultry, offal
G. Fish and seafood
I. Milk and milk products
Each food group is assigned a score of 1 (if consumed) or 0 (if not consumed). The household score will range from 0-12 and is equal to the total number of food groups consumed by the household:
Sum (A + B + C + D + E + F + G + H + I + J + K + L)
The average household dietary diversity score for the population of study can be calculated as follows:
Sum (HDDS)/Total number of households surveyed
If using data that were not initially collected using the HDDS questions (such as Household Consumption and Expenditure (HCES) data), the food items must be regrouped according to the 12 HDDS groups to calculate the indicator. Although there is no universal cut-off or target level that indicates that a household is sufficiently diverse, FANTA suggests two alternatives for using this indicator in a performance reporting context. One option is to use the dietary diversity patterns of wealthier households as a target, which requires the assumption that poorer households will increase their dietary diversity as their incomes rise. A second option is to establish a target using the average dietary diversity of the 33% of households with the highest diversity. For more information on how to set these targets, see FANTA 2006.
This indicator is used as a proxy measure of a household’s food access (Swindale et al. 2006). Unlike measures of dietary diversity collected at the individual level (e.g. Minimum Dietary Diversity for Women (MDD-W) and the Infant and Young Child Minimum Dietary Diversity (IYCMDD)), this indicator has not been validated as a proxy for nutrient adequacy. If the primary concern or research objective is to assess nutrient adequacy of the population, then dietary diversity should be collected using dietary diversity indicators at the individual, not household, level (e.g. MDD-W and IYCMDD). However, if the objective is to assess economic access to food, then the household level indicator is a more appropriate measure (FAO 2011). Because household dietary diversity generally increases as income increases, this indicator is sometimes used as a proxy for household socioeconomic status, and is one of the indicators frequently used to assess how interventions to increase household income have affected food consumption (Swindale et al. 2006).
The HDDS can be used in conjunction with other indicators of food security status (e.g. Household Food Insecurity Access Scale (HFIAS)) to understand household access to certain food groups (Cafiero et al. 2014). The components of the indicator can also be used to examine dietary patterns (e.g., what percentage of households consume any type of animal source foods?). This indicator is required for all USAID Food for Peace (FFP) projects and must be collected at the projects’ baseline and endline to assess the resilience of vulnerable communities and households (USAID 2015). The FAO also uses this indicator and developed a set of guidelines for its use in different contexts (FAO 2011).
Strengths and Weaknesses
One strength of the HDDS is that the standardized questions are simple and can be easily understood by both enumerators and respondents, and the questions usually take less than 10 minutes per respondent (Swindale et al. 2006). The standardized questionnaire provided by the 2011 FAO guidelines is not culture or population specific, so it should be adapted appropriately in adherence with the guidelines before use in a specific context (Kennedy et al. 2011). A drawback of the HDDS is that at the household level, it does not provide information on the adequacy of consumption for specific nutrients, nor does it include foods purchased and consumed outside of the home. In addition, the indicator does not take into account the consumption of fortified foods. Since this indicator uses 24-hour recall, it does not provide an indication of an individual household’s habitual diet, but it can provide an assessment of usual diet at the population level (Kennedy et al. 2011). As discussed above, another weakness of this indicator is that there is no universally accepted cut-off for this indicator that could separate households that have a ‘sufficiently diverse’ diet from those that do not.
The source of data for the HDDS is based on a recall of food groups consumed by the household in the previous 24-hours, reported by the person primarily responsible for food preparation in the household. Other data sources can often be used to construct the HDDS indicator, including Household Consumption and Expenditure Survey (HCES) data, where information on food consumption is collected through a fixed list of foods or food groups.