Mean Ratio Method
For more information, read an Overview of the Methods & Calculations.
The steps of the mean ratio method are:
- 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:
- Constructing Ratios. The appropriate ratios are constructed. 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).
- Calculating Means. The means of the ratios 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.
- Scoring. Each ratio is scored according to the scoring standards. The component scores are summed to calculate the total score.
HEI-2015 Components and Associated 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|
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