Att1_Original Study Protocol Summary

NATIONAL INSTITUTES OF HEALTH – AARP DIET AND HEALTH STUDY
September 2007
STUDY OVERVIEW
This study is being conducted by the National Cancer Institute, Division of Epidemiology and
Genetics, Nutritional Epidemiology Branch. Arthur Schatzkin, M.D., Dr. P.H., Chief of the Nutritional
Epidemiology Branch, is the principal investigator. Westat serves as the coordinator for the study, under
contract to the National Cancer Institute (NCI). The NIH-AARP Diet and Health Study is designed to
prospectively examine the relationship between diet and major cancers (especially those of the breast, large
bowel and prostate) in a sample of early to late middle-aged men and women in the United States. The
study began in 1995. The sampling frame used for this study was the membership roll of the American
Association of Retired Persons (AARP). The AARP is an ideal source of participants for this study
because of the size and demographics of its membership, and its commitment to promoting the health of its
members.
For this study, participants have been asked to provide three types of health information:
1) dietary history information,
2) cancer risk factor information, and
3) cancer diagnosis information.
Historically, observational epidemiologic studies of diet and cancer have suffered from the
problem of dietary homogeneity among the study subjects.

This study overcomes that problem by

collecting dietary data from a very large number of persons, thereby including those persons in the extreme
categories of dietary intake (in terms of fat, fiber and other nutrients). This process ensures that the cohort
is heterogeneous in terms of dietary intake.
The primary method of information collection is mail questionnaires. Questionnaires are
formatted for optical scanning which allows very rapid and accurate data entry, editing, and processing.
Cancer information is collected from population-based cancer registries.

Vital status information is

collected from Westat's copy of the latest Social Security Administration (SSA) mortality database and
from the National Death Index, a federally operated mortality database.
To collect the dietary data needed for the cohort selection process, a baseline questionnaire
(primarily a dietary assessment questionnaire) was mailed to 3.5 million AARP members aged 50 to 69
years sampled from among those who, in 1995, resided in eight states or metropolitan areas selected for the

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study. The states and metropolitan areas were selected based on the quality of the cancer registry, the
number of minority residents, and the willingness of the registry to collaborate with us.

The eight

states/areas included in the study are: California, Florida, Louisiana, New Jersey, North Carolina,
Pennsylvania, the Detroit metropolitan area, and the Atlanta metropolitan area.
Following the baseline questionnaire, a second questionnaire was mailed to those persons who
agreed to participate in the study (i.e., who completed and returned the baseline questionnaire), and who
met the study eligibility criteria. The second questionnaire collected dietary history and additional cancer
risk factor information. Dietary and other data collected in the two questionnaires indicates that the study
cohort of approximately 540,000 persons has a broad range of dietary intake. The cohort is being followed
for outcome assessment in terms of cancer incidence and mortality. Linkages to mortality databases are
performed to learn about mortality events and linkages to cancer registries are performed to collect outcome
(i.e., cancer incidence) information.
A calibration study was also conducted.

The calibration study involved 2,000 study

participants and included 24-hour dietary recall telephone interviews conducted on two separate occasions
with each subject, followed by another mailing of a dietary assessment questionnaire. The 24-hour dietary
recall telephone interview data was compared to the mail questionnaire food frequency data to measure
correlations between the two types of dietary data.
In 2004, an additional component of the study was launched. Collection of buccal cell DNA
from approximately 80,000 participants in the NIH-AARP Diet and Health Study began. Collection
proceeded according to a case-cohort design: cases comprised all surviving cohort members diagnosed
with colorectal, breast, prostate cancer, or non-Hodgkin’s lymphoma after baseline (1995-96); the
comparison subcohort was randomly selected from the cohort as a whole. A total of 77,462 buccal cell kits
were delivered to study participants. Collection was completed in December 2005 and samples sent to an
NCI biorepository for permanent storage. However, the study continued to receipt any late incoming
buccal cell samples through June 2006, and in July transferred these remaining samples to the NCI
biorepository for storage. A total of 34,262 participants returned buccal cell samples and no further
analyses of the samples have been conducted.
In 2004-2006, a follow-up questionnaire was mailed to participants to obtain information on
daily physical activities; smoking; medication, vitamin and supplement use; family history of selected
cancers, and personal history of cancers, other health conditions, and medical procedures. The total number
of respondents to the questionnaire was 318,261. Data is currently being analyzed.

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Westat has subcontracted with National Computer Systems (NCS) to perform the printing,
mailing, receipt, optical scanning, and processing of the mail questionnaires.
DATA SECURITY
All work performed under this contract was reviewed and approved by Westat's Institutional
Review Board (IRB) and the National Cancer Institute’s Special Studies IRB (NCI SSIRB). Both IRBs
have been monitoring, and will continue to monitor, the study activities on an annual basis. The NCI
SSIRB, at the request of the NCI principal investigator, will determine if any other NIH institute, academic
institution, or contractor may be involved in ancillary studies utilizing data for analysis or personal
identifiers for contacting study participants.
All NCI and Westat employees who work with data must sign a pledge of confidentiality and
complete annual human subjects training. Individual subject data is not disclosed to anyone except the
researchers conducting the study, except as required by law.

No information that would enable the

identification of individuals is included on any data file used for analysis.

Westat ensures the

confidentiality of all data, as required by Section 308(d) of the Public Health Service Act and the U.S.
Privacy Act of 1974. Paper records containing personal identifiers are kept in locked file rooms at both
Westat. When the study is complete, all hard-copy records will be delivered to NCI, stored in a locked
vault, or destroyed, depending upon the direction of NCI. Westat believes these procedures to be extremely
effective in ensuring that risks to the subjects are minimized and that the confidentiality of the data is
maintained.

INVESTIGATORS
NCI Principal Investigator:

Westat Project Director:

Arthur Schatzkin, M.D., Dr.P.H.
Chief, Nutritional Epidemiology Branch
National Cancer Institute
Executive Plaza South, Room 7040
Rockville, MD 20892
Telephone: (301) 594-2931

Kerry Grace Morrissey, M.P.H.
Westat
1650 Research Blvd., TB312
Rockville, MD 20850
Telephone: (240) 453-2742
Fax: (301) 294-2092

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