Table 4.

Prevalence of respirator use among farm operators by characteristic and asthma status.

Characteristic	No asthma diagnosis				Current asthma, farm work related				Current asthma, not farm work related
	Proportion of operators using respirators	95% CI*	aPOR respirator vs. no respirator* †	95% CI*	Proportion of operators using respirators	95% CI*	aPOR respirator vs. no respirator*†	95% CI*	Proportion of operators using respirators	95% CI*	aPOR respirator vs. no respirator*†	95% CI*
Demographic characteristics
Age group
16–64	38.6	37.0–40.2	1.00 (Ref)		57.9	42.3–73.6	1.00 (Ref)		47.0	38.4–55.6	1.00 (Ref)
65+	28.5	26.5–30.5	0.6	0.6–0.7	69.7	52.0–87.4	2.0	0.6–6.7	41.1	31.8–50.4	0.7	0.4–1.2
Sex
Male	37.3	36.0–38.7	1.7	1.4–2.0	***				48.7	41.4–56.0	1.5	0.7–3.1
Female	22.9	20.0–25.8	1.00 (Ref)		***				31.3	18.7–43.8	1.00 (Ref)
Martial status
Married or living with partner	36.8	35.4–38.3	1.4	1.2–1.6	***				49.4	42.3–56.5	2.9	1.4–5.9
Widowed, divorced, separated, single	26.8	24.0–29.6	1.00 (Ref)		***				22.7	12.4–33.0	1.00 (Ref)
Smoking
Current or former smoker	33.1	31.1–35.2	1.1	1.0–1.2	63.0	39.9–86.2	1.0	0.3–3.4	42.2	32.8–51.6	1.2	0.7–2.1
Never smoker	36.3	34.7–37.9	1.00 (Ref)		60.1	43.1–77.1	1.00 (Ref)		46.4	38.0–54.7	1.00 (Ref)
Second job
Yes	34.8	33.0–36.7	1.1	1.0–1.2	63.0	42.7–83.4	1.4	0.4–4.2	45.0	35.4–54.7	0.9	0.5–1.6
No	35.2	33.5–37.0	1.00 (Ref)		58.5	41.7–75.3	1.00 (Ref)		43.8	35.6–52.0	1.00 (Ref)
Farm characteristics
Farm value of sales
<$100,000	51.3	49.0–53.6	0.5	0.4–0.5	62.7	43.7–81.9	1.1	0.3–3.7	54.2	40.7–67.7	0.7	0.4–1.2
≥$100,000	31.6	30.1–33.0	1.00 (Ref)		59.9	42.8–77.1	1.00 (Ref)		43.1	36.0–50.1	1.00 (Ref)
Region§
Northeast	32.3	30.2–34.3	1.00 (Ref)		54.7	38.9–70.6	1.00 (Ref)		36.7	26.2–47.3	1.00 (Ref)
Midwest	34.4	32.3–36.5	1.0	0.8–1.1	55.2	25.8–84.7	0.9	0.2–3.6	44.6	32.5–56.6	1.3	0.6–2.5
South	35.2	32.9–37.4	1.3	1.1–1.5	71.6	47.1–96.1	1.1	0.2–5.1	42.8	31.4–54.2	1.5	0.7–3.0
West	37.6	35.6–39.6	1.3	1.2–1.5	52.8	34.8–70.8	1.0	0.3–3.3	49.7	41.0–58.5	1.9	1.0–3.5
Farm type
Crops	38.3	36.5–40.1	1.4	1.3–1.6	55.3	33.9–76.7	0.7	0.2–2.0	47.8	38.3–57.3	1.4	0.8–2.4
Livestock	32.0	30.2–33.7	1.00 (Ref)		65.6	48.0–83.3	1.00 (Ref)		41.4	32.7–50.0	1.00 (Ref)
Farm size
<101 acres	31.8	30.1–33.5	1.0	0.8–1.2	51.2	32.5–69.9	0.1	0.0–0.5	43.4	35.2–51.6	1.2	0.4–3.8
101–999	39.1	37.1–41.0	1.1	0.9–1.3	65.8	47.4–84.2	0.2	0.0–1.3	46.6	36.7–56.5	1.2	0.4–3.7
≥1000	50.2	46.2–54.2	1.00 (Ref)		79.7	57.9–100	1.00 (Ref)		46.6	24.6–68.7	1.00 (Ref)
Farm exposures and hazards
Bale hay¶
Yes	37.8	35.9–39.8	1.1	1.0–1.2	59.6	44.8–74.4	0.7	0.2–2.5	48.9	38.3–59.5	1.2	0.7–2.0
No	33.2	31.5–34.8	1.00 (Ref)		61.8	41.8–81.7	1.00 (Ref)		42.1	34.2–50.1	1.00 (Ref)
Manure storage**
Yes	51.4	46.0–56.9	1.6	1.3–2.1	***				69.7	51.4–87.9	3.1	1.2–7.8
No	34.3	33.0–35.5	1.00 (Ref)		***				43.1	36.5–49.6	1.00 (Ref)
Grain production††
Yes	50.6	47.9–53.3	2.0	1.7–2.3	78.4	64.3–92.5	3.7	1.3–10.6	59.2	47.2–71.3	1.8	1.0–3.4
No	31.1	29.7–32.5	1.00 (Ref)		52.0	34.5–69.4	1.00 (Ref)		41.7	34.6–48.8	1.00 (Ref)
Animals§§
Yes	34.2	32.7–35.7	0.9	0.8–1.1	61.0	43.2–78.7	0.6	0.2–2.4	45.3	37.6–53.1	1.2	0.6–2.4
No	36.8	34.5–39.1	1.00 (Ref)		60.3	37.6–82.9	1.00 (Ref)		42.4	31.3–53.6	1.00 (Ref)
Pesticides¶¶
Yes	53.7	51.6–55.8	3.4	3.0–3.9	77.7	62.9–92.5	7.9	2.2–28.1	60.7	51.3–70.2	3.2	1.8–5.5
No	22.9	21.4–24.3	1.00 (Ref)		34.2	18.5–49.9	1.00 (Ref)		30.8	23.0–38.6	1.00 (Ref)

Note. Numbers in bold show a statistically significant difference between groups where P ≤ .05.

^*CI = confidence interval; aPOR = adjusted prevalence odds ratio.

^†aPOR was adjusted for age, sex, region, farm type, and value of sales.

^§Northeast: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont, New Jersey, New York, Pennsylvania; Midwest: Illinois, Indiana, Michigan, Ohio, Wisconsin, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota; South: Delaware, District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, West Virginia, Alabama, Kentucky, Mississippi, Tennesse, Arkansas, Louisiana, Oklahoma, Texas; West: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming, Alaska, California, Hawaii, Oregon, Washington

^¶Exposure to baling hay was defined with the question: “Do you/Does the Farm Operator bale hay or straw on the farm?”

^**Exposure to manure storage was defined using the question: “Do you/Does the Farm Operator have any manure storage facilities on the farm or ranch?”

^††Exposure to grain production was defined using the questions: “How many PTO-driven Feed Mixers or Forage Grinders (do you/does the farm operator) have?”; “How many silage blowers (do you/does the Farm Operator) have?”; “How many PTO-driven portable grain augers (do you/does the Farm Operator) have?”; “How many stand alone grain bins with a capacity of 5000 bushel or more (do you/does the Farm Operator) have on the farm or ranch?”; “(Do you/Does the Farm Operator) use trenches on the farm or ranch for grain or animal feed storage?”

^§§Exposure to animals was defined using the questions: “In the last 12 months (have you/has the Farm Operator) kept any large animals such as cattle, bison, horses, donkeys, ponies, mules or hogs?”; “(Do you/Does the Farm Operator have any beef cattle or bison on the farm or ranch?”; “(Do you/Does the Farm Operator have any dairy cattle on the farm or ranch?”; “(Do you/Does the Farm Operator have a dairy bull on the farm or ranch?”; “(Do you/Does the farm operator) have any horses or other equine such as ponies, mules, donkeys, or burros on the farm or ranch?”; “(Do you/Does the Farm Operator) have any hogs or pigs on the farm or ranch, whether owned by (you/them) or by someone else?”

^¶¶Exposure to pesticides was defined using the question: “In the past 12 months, (have you/has the farm operator) ever mixed, loaded, or applied pesticides on your farm?”

^***The coefficient of variation for these estimates was >30% and considered unstable.