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Dietary Screener in the 2005 CHIS
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Diet Screener in the 2005 CHIS: Scoring Procedures
How Analytical Scoring Procedures Were Developed
Scoring procedures were developed to convert the individual respondent's screener
responses to estimates of individual dietary intake for servings of fruits and vegetables
and teaspoons of added sugar using USDA's
1994-96 Continuing Survey of Food Intakes of
Individuals (CSFII 94-96) dietary recall data.
For servings of fruits and vegetables:
E(Fruits and Veg1/2) =
b0 + b1(NFG1P1 + NFG2P2 +
... + NFG7P7)1/2
Servings of fruits and vegetables was square-root-transformed to approximate normality;
NFGk is the usual number of times per day an individual consumed food group k; k indexes
the 7 fruit and vegetable food groups. Pk is the median portion size of group k. We
calculated weighted least-squares estimates of the regression coefficients b0 and b1 on
the adults (aged 18 and above) in the CSFII 94-96 sample, stratifying by gender and
excluding extreme exposure values.
Scoring Procedures
After excluding extreme and missing values, we performed the following steps with the
CHIS dietary data to estimate the individual's intake of servings of fruits and
vegetables.
- Estimation of NFGk:
All reported frequencies were standardized to a common unit of
time by converting them to daily frequencies.
| Time Period Reported |
NFGk: Daily Frequency |
| Day |
As reported |
| Week |
Reported frequency divided by 7 |
| Month |
Reported frequency divided by 30 |
For Fruit and Vegetable Intake:
- Estimation of Pk:
The median age- and gender-specific portion sizes for each food were estimated from CSFII
94-96. The units were in Pyramid servings (Table 1).
A Pyramid serving is defined by the U.S. Department of Agriculture in the 1992 Dietary
Guidelines Food Guide Pyramid as:
- vegetables: 1 cup raw leafy, 1/2 cup of other vegetables, or 3/4 cup vegetable juice; and
- fruit: 1 whole fruit, 1/2 cup of cut-up fruit, or 3/4 cup fruit juice.
More recently, the 2005 Dietary Guidelines measure fruits and vegetables in cup equivalents. See MyPyramid for definitions of cup equivalents.
Both metrics are provided for these 2005 data.
Table 1a. Median Portion Size (Pk) in Pyramid Servings* per Mention by Gender and Age for Fruits and Vegetables Analyses
| Food Group |
Age Group |
| 18-27 |
28-37 |
38-47 |
48-57 |
58-67 |
68-77 |
78-99 |
| Men |
| 100% fruit juice (P1) |
2.000000 |
1.667500 |
1.335000 |
1.335000 |
1.334000 |
1.001000 |
1.001000 |
| Fruit (P2) |
1.301000 |
1.301000 |
1.229571 |
1.227333 |
1.168000 |
1.168000 |
1.052333 |
| Salad (P3) |
0.545000 |
0.708000 |
0.754500 |
0.750000 |
0.833500 |
0.750000 |
0.822500 |
| Fried potatoes (P4) |
2.000000 |
2.000000 |
1.773000 |
1.710000 |
1.400000 |
1.250000 |
1.250000 |
| Other white potatoes (P5) |
2.000000 |
2.000000 |
1.999000 |
1.999000 |
1.914000 |
1.544000 |
1.508000 |
| Dried beans (P6) |
1.374000 |
1.047000 |
1.065000 |
1.227000 |
1.000000 |
1.000000 |
1.114000 |
| Other vegetables (P7) |
0.750000 |
0.906000 |
0.974500 |
1.000000 |
1.000000 |
0.880000 |
0.833333 |
| Women |
| 100% fruit juice (P1) |
1.500500 |
1.334000 |
1.334000 |
1.251250 |
1.019500 |
1.000500 |
1.000500 |
| Fruit (P2) |
1.168000 |
1.168000 |
1.168000 |
1.168000 |
1.150500 |
1.083833 |
1.000000 |
| Salad (P3) |
0.613500 |
0.572500 |
0.833333 |
1.000000 |
0.795500 |
0.625000 |
0.750000 |
| Fried potatoes (P4) |
1.481000 |
1.365500 |
1.272000 |
1.400000 |
1.000000 |
1.026000 |
1.000000 |
| Other white potatoes (P5) |
1.544000 |
1.544000 |
1.528000 |
1.544000 |
1.499000 |
1.516000 |
1.272000 |
| Dried beans (P6) |
0.964000 |
0.684000 |
0.800000 |
0.687000 |
0.822000 |
0.807000 |
1.000000 |
| Other vegetables (P7) |
0.702200 |
0.779333 |
0.792500 |
0.788500 |
0.774000 |
0.833000 |
0.856750 |
Table 1b. Median Portion Size (Pk) in Cup Equivalents** per Mention by Gender and Age for Fruits and Vegetables Analyses
| Food Group |
Age Group |
| 18-27 |
28-37 |
38-47 |
48-57 |
58-67 |
68-77 |
78-99 |
Men |
| 100% fruit juice (P1) |
1.499160 |
1.250580 |
1.000980 |
1.000980 |
1.000176 |
0.750735 |
0.750735 |
| Fruit (P2) |
0.999580 |
0.933450 |
0.867300 |
0.867300 |
0.867300 |
0.774916 |
0.657060 |
| Salad (P3) |
0.272700 |
0.353970 |
0.377235 |
0.374963 |
0.416640 |
0.375000 |
0.411323 |
| Fried potatoes (P4) |
0.721125 |
0.727700 |
0.641000 |
0.641000 |
0.548055 |
0.480750 |
0.499980 |
| Other white potatoes (P5) |
1.000400 |
1.140030 |
0.999600 |
0.999600 |
0.999490 |
0.833175 |
0.754400 |
| Dried beans (P6) |
0.717550 |
0.551540 |
0.566720 |
0.612360 |
0.500250 |
0.502285 |
0.575360 |
| Other vegetables (P7) |
0.387675 |
0.473920 |
0.499840 |
0.500240 |
0.499905 |
0.460585 |
0.416899 |
| Women |
| 100% fruit juice (P1) |
1.124370 |
1.000960 |
1.000176 |
0.938130 |
0.764776 |
0.750728 |
0.750434 |
| Fruit (P2) |
0.749235 |
0.867300 |
0.844838 |
0.789970 |
0.742350 |
0.712640 |
0.620475 |
| Salad (P3) |
0.306788 |
0.286335 |
0.416625 |
0.499950 |
0.397688 |
0.312469 |
0.374963 |
| Fried potatoes (P4) |
0.509595 |
0.455110 |
0.448700 |
0.448700 |
0.394856 |
0.444260 |
0.444260 |
| Other white potatoes (P5) |
0.782020 |
0.876945 |
0.771260 |
0.771260 |
0.749700 |
0.771260 |
0.644235 |
| Dried beans (P6) |
0.492150 |
0.341550 |
0.430530 |
0.345763 |
0.430685 |
0.430530 |
0.500400 |
| Other vegetables (P7) |
0.364468 |
0.395882 |
0.404303 |
0.408330 |
0.416913 |
0.436560 |
0.452214 |
- For Pyramid servings of fruits and vegetables, estimation of b0 and b1:
The model is: E(Dietary Factor1/2) =
b0 + b1 (NFG1P1 + NFG2P2 +
... + NFG7P7)1/2
For Pyramid servings of fruits and vegetables, including and excluding French fries and dried beans, for each gender, the estimates of the parameters are:
Table 2a. Estimated Regression Coefficients for Sum of Foods Predicting Pyramid Servings* of Different Versions of Daily Servings of Fruits and Vegetables, by Gender
| Parameter |
Men |
Women |
| Summary Variable with French fries |
| Intercept (b0) |
0.906793 |
0.819559 |
| b1 |
0.758560 |
0.730865 |
| Summary Variable excluding French fries |
| Intercept (b0) |
0.940772 |
0.816265 |
| b1 |
0.739056 |
0.730219 |
| Summary Variable excluding French fries and beans |
| Intercept (b0) |
0.950228 |
0.813568 |
| b1 |
0.723395 |
0.723230 |
| Summary Variable excluding beans |
| Intercept (b0) |
0.884786 |
0.813994 |
| b1 |
0.761347 |
0.726001 |
Table 2b. Estimated Regression Coefficients for Sum of Foods Predicting Different Versions of Daily Cup Equivalents of Fruits and Vegetables**, by Gender
| Parameter |
Men |
Women |
| Summary Variable with French fries |
| Intercept (b0) |
0.666228 |
0.611844 |
| b1 |
0.770652 |
0.733890 |
| Summary Variable excluding French fries |
| Intercept (b0) |
0.706696 |
0.616033 |
| b1 |
0.742255 |
0.727761 |
Summary Variable excluding French fries and beans |
| Intercept (b0) |
0.719659 |
0.618209 |
| b1 |
0.723629 |
0.718681 |
| Summary Variable excluding beans |
| Intercept (b0) |
0.671443 |
0.613051 |
| b1 |
0.758684 |
0.725692 |
For teaspoons of added sugar:
- Estimation of Pk:
The median age- and gender-specific portion sizes in grams for each food were estimated from CSFII 94-96 (Table 3).
Table 3. Median Portion Size (Pk) in Teaspoons*** per Mention by Gender and Age for Added Sugar Analyses
| Food Group |
Age Group |
| 18-27 |
28-37 |
38-47 |
48-57 |
58-67 |
68-77 |
78+ |
| Men |
| Regular soda (P1) |
11.246397 |
9.221880 |
9.221880 |
9.221880 |
9.214440 |
9.125268 |
9.115360 |
| Fruit drinks (P2) |
10.600000 |
8.636250 |
8.565000 |
8.565000 |
6.276880 |
5.700512 |
5.540320 |
| Cookies, cake, pie (P3) |
5.083032 |
4.762847 |
4.582705 |
4.426306 |
4.552020 |
4.216712 |
3.761836 |
| Ice cream (P4) |
7.046725 |
5.905380 |
6.783700 |
5.858650 |
5.858650 |
4.759920 |
3.478629 |
| Women |
| Regular soda (P1) |
9.221880 |
9.221880 |
9.184695 |
9.125268 |
8.041256 |
7.684900 |
9.120314 |
| Fruit drinks (P2) |
8.246250 |
7.773757 |
6.276880 |
6.218740 |
6.251570 |
5.353125 |
5.300000 |
| Cookies, cake, pie (P3) |
3.945000 |
3.533487 |
3.649440 |
3.595380 |
3.866728 |
3.315540 |
3.027309 |
| Ice cream (P4) |
5.858650 |
5.546760 |
5.814600 |
4.933600 |
4.560570 |
3.920450 |
3.920450 |
- For teaspoons of added sugar, estimation of b0 and b1:
The model is: E(Dietary Factor1/3) =
b0 + b1 (NFG1P1 + NFG2P2 +
... + NFG4P4)1/3
For teaspoons of added sugar, estimates of the parameters are:
Table 4. Estimated Regression Coefficients for Sum of Foods Predicting Teaspoons of Added Sugar***, by Gender
| Parameter |
Men |
Women |
| Intercept (b0) |
1.566813 |
1.481876 |
| b1 |
0.555082 |
0.514735 |
* Using 1992 Food Guide Pyramid definitions of servings.
** Using 2005 MyPyramid definitions of cups of fruits and vegetables.
*** Using 2005 MyPyramid database.
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