Population Ratio Method

For more information, read an Overview of the Methods & Calculations.

The steps of the population ratio method are:

1. Deriving Sums. For each HEI component, dietary constituents are summed together (e.g., Greens and Beans is created from the sum of dark green vegetables and legumes (beans and peas)).

   For the HEI-2015, the components and associated dietary constituents are noted below:

   HEI-2015 Components and Associated Dietary Constituents

   Components	Units	Dietary Constituents
   From FPED (or other food-based database)
   Whole Fruits	cup eq.	Citrus, Melons, Berries + Other Intact Fruits
   Total Fruits	cup eq.	Total Fruit
   Greens and Beans	cup eq.	Dark Green Vegetables + Legumes (Beans and Peas) in cup equivalents
   Total Vegetables	cup eq.	Total Vegetables + Legumes (Beans and Peas) in cup equivalents
   Whole Grains	oz. eq.	Whole Grains
   Refined Grains	oz. eq.	Refined Grains
   Dairy	cup eq.	Total Dairy
   Seafood and Plant Proteins	oz. eq.	Seafood (high in n-3) + Seafood (low in n-3) + Soy Products + Nuts and Seeds + Legumes (Beans and Peas) in oz equivalents
   Total Protein Foods	oz. eq.	Total Meat, Poultry, and Seafood (including organ meats and cured meats) + Eggs + Nuts and Seeds + Soy + Legumes (Beans and Peas) in oz equivalents
   Added Sugars	tsp. eq.	Added Sugars
   From FNDDS (or other nutrient database)
   Fatty Acids	g	(Total Monounsaturated Fatty Acids + Total Polyunsaturated Fatty Acids)/Total Saturated Fatty Acids
   Saturated Fats	g*	Total Saturated Fatty Acids
   Sodium	mg	Sodium
   Energy	kcal	Total Energy

   cup eq.=cup equivalents; oz. eq.=ounce equivalents; tsp. eq.=teaspoon equivalents; g=grams; g*= fatty acids are calculated in grams but converted to energy in the scoring process; mg=milligrams

2. Calculating Means. The means of each of the dietary constituents across individuals are computed. When more than one 24HR is available, the score is calculated in the same manner, using both recalls for a participant.

3. Constructing Ratios. The appropriate ratios are constructed for the population. Usually these are the ratios of the dietary constituents to 1000 kcal of energy, with the exception of fatty acids, which use the ratio of the sum of monounsaturated and polyunsaturated fatty acids to saturated fatty acids. (Also, note two components are expressed on a percent of calories basis. Therefore, grams of saturated fat should be multiplied by 9 to convert g to kcal, and added sugars should be multiplied by 16 to convert teaspoons to kcal, prior to dividing by total energy).

4. Scoring. Each ratio is scored according to the algorithm. The component scores are summed to calculate the total score.