Nurses Health Study I

The Nurses Health Study (NHS) questionnaire had the following questions involving chicken skin.

When you eat chicken, how often is it cooked with the skin on?

always
most of the time
sometimes
never

How often do you eat the skin?

always
most of the time
sometimes
never

The same calculations were applied to NHS as the Health Professionals Follow-up Study (HPFS). In order to account for the four answers, the following percentages were applied:

Always (100%)
Most of the time (75%)
Sometimes (50%)
Never (0%)

The following table illustrates the number of different combinations possible.

Percentage used in calculation	Cook with skin	Eat skin
100% cook w/skin and eat w/skin	Always	Always
75% cook w/skin and eat w/skin 25% cook w/skin and eat w/o skin	Always	Most
50% cook w/skin and eat w/skin 50% cook w/skin and eat w/o skin	Always	Sometimes
100% cook w/skin and eat w/o skin	Always	Never
25% cooked w/o skin 75% cooked w/skin and eat w/skin	Most	Always
25% cooked w/o skin, 56% cooked w/ skin and eat w/skin 19% cooked with skin and eat w/o skin	Most	Most
25% cooked w/o skin 37.5% cooked w/skin and eat w/skin 37.5% cooked with skin and eat w/o skin	Most	Sometimes
25% cooked w/o skin 75% cooked w/skin and eat w/o skin	Most	Never
50% cooked w/o skin 50% cooked w/skin and eat w/skin	Sometimes	Always
50% cooked w/o skin 37.5% cooked w/skin and eat w/skin 12.5% cooked with skin and eat w/o skin	Sometimes	Most
50% cooked w/o skin 25% cooked w/skin and eat w/skin 25% cooked with skin and eat w/o skin	Sometimes	Sometimes
50% cooked w/o skin 50% cooked with skin and eat w/o skin	Sometimes	Never
100% cooked w/o skin	Never	Never

A complete listing of the values is available.

For more information:

Kana Wu, MD, PhD
Harvard School of Public Health
Department of Nutrition
665 Huntington Avenue
Boston, MA 02115
Tel. 617-432-1842
Fax. 617-432-2435
e-mail:kana.wu@channing.harvard.edu