Questionnaires & Study Data

The AHS cohort includes 89,655 private pesticide applicators (mostly farmers), spouses of private applicators, and commercial pesticide applicators recruited in Iowa and North Carolina (Table 1). Note, phase-specific response rates are shown for total enrolled cohort, while individual participation rates in Phase eligible samples are reported below. Participants were recruited from 1993 to 1997. Active follow-up efforts were conducted in 1999-2003 (Phase 2), 2005-2010 (Phase 3), 2013-2015 (Phase 4), and 2019-2021 (Phase 5). Calculated percent of the total enrolled sample with follow-up data are shown in Table 1. The Phase 2 interview was completed by 64% of private applicators, 59% of commercial applicators, and 74% of spouses. Participants provided updated information on farming practices, lifestyle, and health and were asked to complete a dietary questionnaire and provide a sample of cheek cells as a source of DNA. Starting in Phase 3, active follow-up was limited to a smaller sample of private applicators and spouses who had completed at least one prior cohort activity (i.e., besides completing the enrollment questionnaire, completing the take-home or Phase 2 surveys). Phase 3 to 5 questionnaires updated information on farming practices, lifestyle, and health. Phase 3 also updated pesticide data, including lifetime use in spouses, and was completed by 46% of enrolled private applicators and 61% of enrolled spouses. Phase 4 was completed by follow up 47% of the enrolled private applicators and 61% of enrolled spouses. The Phase 5 (2019-2021) questionnaire also collected new data on farming-related stress, and was completed by 35% of enrolled private applicators and 42% of spouses. All enrolled applicators (private and commercial) and spouses are passively followed for cancer and mortality through registry linkages and through the United States Renal Data System (USRDS). For participants ages 65 years and older, linkage to Medicare administrative claims data enables health status updates based on diagnostic and other codes used for billing purposes.

Questionnaires Used in the AHS

Phase 1

• Enrollment, Commercial Applicator (PDF, 500 KB)
• Enrollment, Private Applicator (PDF, 1.8 MB)
• Take-Home Applicator (PDF, 2 MB)
• Female & Family Health (PDF, 680 KB)
• Spouse (PDF, 842 KB)

Phase 2

• Commercial Applicator (PDF, 222 KB)
• Cooking Practices Module (PDF, 384 KB)
• Diet History Questionnaire (PDF, 4.2 MB)
• Follow-up Health for Women (Version A) (PDF, 524 KB)
• Follow-up Health for Women (Version B) (PDF, 562 KB)
• Follow-up Health for Women (Version C - applicator) (PDF, 504 KB)
• Follow-up Health for Women (Version C - spouse) (PDF, 760 KB)
• Health Module Men (PDF, 300 KB)
• Pesticide Use Module Applicator (PDF, 640 KB)
• Pesticide Use Module Spouse (PDF, 553 KB)

Phase 3

• Phase 3 Questionnaire (PDF, 648 KB)

Phase 4

• Phase 4 Questionnaire (PDF, 319 KB)

Phase 5

• Phase 5 Questionnaire (Compressed) (PDF, 7.94 MB)
• Phase 5 Questionnaire (Accessible) (PDF, 84.8 MB)

Phase 1 (1993-1997) Questionnaires
Self-administered questionnaires obtained information on lifetime pesticide use, and demographic and medical history information.

Applicators were asked to complete two questionnaires—one that was filled out at a pesticide training/licensing location and one to be filled out at home and mailed back. Over 80% of licensed applicators enrolled in the study by completing the on-site form, and 44% of these also completed the take-home questionnaire. Although the content was similar, the take-home questionnaire obtained more detailed information on some pesticides, as well as some details of medical history and information on some covariates (e.g., BMI).

Private applicators were also given questionnaires to be filled out by their spouse, and 75% of married spouses completed them to enroll. Sixty percent of women who enrolled (both spouses and female applicators) completed a Female and Family Health questionnaire that obtained reproductive histories and information about children.

Phase 2 (1999-2003) and Phase 3 (2005-2010) Follow-up Questionnaires
These phases involved computer-assisted telephone interviews to obtain information on current pesticide use, potential confounders, and medical history.

In Phase 2, exposure questions were similar for applicators and spouses, and the health questionnaires varied slightly by gender and age: 67% percent of the enrolled cohort completed questionnaires. In addition, participants who completed the follow-up survey were asked to do a self-completed food frequency questionnaire (the NCI Diet History Questionnaire, with added items on cooking practices). About 39% of the cohort completed the diet questionnaire. Buccal cell samples (for DNA) were also collected from 39% of the total cohort.

In Phase 3, a common instrument was used for better integration of data for applicators and spouses. Questionnaires updated information on pesticide use, farming status, potential confounders, and medical history. Eligibility for Phase 3 was limited to private applicators (mostly farmers) and spouses who had done at least one prior cohort activity besides completing the enrollment questionnaire. Approximately 60% of eligible applicators and 66% of spouses completed Phase 3 (about 49% of the total cohort).

Phase 4 (2013-2015) Follow-Up Questionnaire
Data were collected by self-administered and telephone computer-assisted telephone interviews, with questions focused on updating important covariates such as farming status, smoking and family history of disease and non-cancer chronic diseases, including diseases of aging.

Approximately 70,000 Phase 3 eligible private applicators and spouses were invited to participate regardless of whether they participated in the Phase 3. For the first time, data were also collected from next-of-kin for participants who were incapacitated or deceased. The data collection was done primarily by self-administered mailed questionnaires and computer assisted telephone interviews. Approximately 61% of eligible participants or their proxies completed the Phase 4 survey (about 47% of the enrolled cohort).

Phase 5 (2019-2021) Follow-Up Questionnaire
Data were collected by online and self-administered questionnaires, and computer-assisted telephone interviews, with questions that focused on updating important covariates such as farming status, smoking and family history of disease and non-cancer chronic diseases, diseases of aging including, for the first time questions on memory loss and cognitive disorders, and chronic pain and sleep. New questions were included on perceived stress, life events, and farming-related stressors, including losses due to natural disasters such as storms and flooding.

Approximately 64,000 eligible private applicators and spouses were invited to participate in the Phase 5 survey regardless of whether they participated in Phases 3 or 4. Data were also collected from next-of-kin for participants who were incapacitated or deceased. Approximately 32,000 (50%) of eligible participants or their proxies completed the Phase 5 survey (about 36% of the enrolled cohort).

Table 1: AHS Cohort-wide Data Collection