Understanding the Household Dietary Diversity Score
The Household Dietary Diversity Score (HDDS) is a powerful tool for measuring household food security. Developed by FANTA in partnership with FAO, it quantifies the number of different food groups consumed by a household over a specific recall period, typically the previous 24 hours. A higher HDDS is strongly correlated with increased caloric and protein adequacy, as well as higher-quality protein intake. Unlike more complex dietary assessments, the HDDS is designed for rapid and easy administration, making it a valuable indicator for large-scale surveys and program monitoring. It is important to note, however, that while HDDS is a good proxy for food access, it does not quantify the amount of food consumed or individual-level nutrient adequacy.
The Standard 12 Food Groups for Calculation
The calculation relies on a standardized list of 12 food groups. During data collection, a enumerator asks a household member, typically the primary food preparer, whether any member of the household consumed food from each of these groups during the previous 24 hours. A "yes" response is marked for each food group consumed, and a simple sum provides the household's total score. The 12 food groups are as follows:
- Cereals: Includes items like wheat, maize, rice, and other grains.
- Roots and tubers: Such as potatoes, sweet potatoes, and cassava.
- Vegetables: Encompasses all vegetables, with a specific focus on vitamin A-rich and dark green leafy varieties.
- Fruits: All types of fresh or processed fruits.
- Meat: Includes beef, goat, pork, etc..
- Eggs: All types of eggs.
- Fish and other seafood: Any fish or other aquatic animals.
- Legumes, nuts, and seeds: Includes items like beans, lentils, peanuts, and other seeds.
- Milk and dairy products: Milk, yogurt, cheese, etc..
- Oils and fats: Includes cooking oils, animal fats, and butter.
- Sugars/honey: Sugar and honey.
- Miscellaneous: Includes items like spices, condiments, and beverages like tea or coffee.
Step-by-Step Guide to Calculating the HDDS
- Preparation: First, develop or adapt a standardized questionnaire listing the 12 food groups. Training for enumerators is essential to ensure consistent questioning and accurate recording, especially concerning mixed dishes and composite ingredients. Avoid collecting data on special days with unusually diverse or restricted diets, such as festivals or fasts, to ensure the score reflects typical consumption patterns.
- Data Collection: Conduct interviews with the household member responsible for preparing food. Use a 24-hour recall period, starting with the first meal or drink of the previous day and working backward. Ask about snacks and ingredients in mixed dishes. Confirm that the food was consumed by at least one member of the household. Remember to exclude foods purchased and eaten outside the home, as the respondent may not know the contents.
- Recording Responses: For each of the 12 food groups, record a "1" if food from that group was consumed and a "0" if it was not. This creates a binary yes/no response for each group.
- Calculation: To get the HDDS for a single household, simply sum the scores from the 12 food groups. The resulting score can range from 0 to 12.
- Aggregating Results: For survey purposes, HDDS for a group can be calculated by summing the scores of all assessed households and dividing by the total number of households surveyed. This provides an average HDDS for the population being studied.
Interpreting and Using the HDDS
The raw HDDS provides a numerical representation of dietary diversity, but its real value lies in its interpretation. A higher score suggests greater food access and a more varied diet, which is linked to better nutritional outcomes. While there are no universal cut-off points, the scores can be used to categorize households and compare populations. Organizations like FANTA and FAO recommend using the dietary diversity of wealthier households or the top one-third of the study population as a benchmark to establish a context-specific target.
HDDS vs. Food Consumption Score (FCS)
| Feature | Household Dietary Diversity Score (HDDS) | Food Consumption Score (FCS) |
|---|---|---|
| Recall Period | 24 hours | 7 days |
| Number of Food Groups | 12 standard groups | 8 standard groups with weighted scoring |
| Purpose | Measures qualitative food consumption and economic access | Measures household food consumption frequency and qualitative access |
| Output | A simple count (0-12) | A weighted score |
| Primary Promoter | FAO | WFP |
Conclusion
The Household Dietary Diversity Score is an indispensable tool for public health practitioners, researchers, and policymakers working on nutrition and food security issues. Its straightforward calculation method, based on a 24-hour recall of 12 food groups, offers a rapid and reliable way to assess a household's access to a diverse diet. By providing insight into qualitative food consumption patterns, the HDDS helps target interventions and monitor the effectiveness of programs aimed at improving nutritional well-being. While it has certain limitations, understanding how to calculate household dietary diversity score correctly is the first step toward effective nutritional program implementation and evaluation. For more detailed guidelines on implementation, the Food and Agriculture Organization provides comprehensive resources.
Outbound Link: For extensive technical guidance on implementing the HDDS indicator, consult the FAO guidelines.
