Table 2.
Distribution of Person-Weeks During the Entire Follow-up Period and According to Self-reported Sun Exposure, Herpetic Eye Disease Study, 1993–1997
| Reported Sun Exposure, hours/week |
|||||||||
|---|---|---|---|---|---|---|---|---|---|
| Characteristic | Total Follow-up (10,163 PW) |
≤7 (7,169 PW) |
≥8 (2,994 PW) |
||||||
| No. | % | Median (IQR) | No. | % | Median (IQR) | No. | % | Median (IQR) | |
| Age at randomization, years | 52 (39–65) | 52 (40–66) | 49 (36–63) | ||||||
| Female gender | 4,822 | 47 | 3,616 | 50 | 1,206 | 40 | |||
| Race/ethnicity | |||||||||
| White | 8,933 | 88 | 6,350 | 89 | 2,583 | 86 | |||
| African-American | 565 | 6 | 382 | 5 | 183 | 6 | |||
| Othera | 665 | 6 | 437 | 6 | 228 | 8 | |||
| Acyclovir treatment group | 5,337 | 53 | 3,708 | 52 | 1,629 | 54 | |||
| Study center location | |||||||||
| New Orleans, Louisiana | 955 | 9 | 655 | 9 | 300 | 10 | |||
| Houston, Texas | 755 | 7 | 616 | 9 | 139 | 5 | |||
| San Francisco, California | 1,929 | 19 | 1,253 | 17 | 676 | 23 | |||
| Atlanta, Georgia | 1,878 | 18 | 1,383 | 19 | 495 | 17 | |||
| Chicago, Illinois | 1,560 | 15 | 1,046 | 15 | 514 | 17 | |||
| Milwaukee, Wisconsin | 1,525 | 15 | 1,062 | 15 | 463 | 15 | |||
| Philadelphia, Pennsylvania | 697 | 7 | 517 | 7 | 180 | 6 | |||
| New York, New York | 864 | 9 | 637 | 9 | 227 | 8 | |||
| Current use of contact lensesb | 1,024 | 10 | 787 | 11 | 237 | 8 | |||
| Use of glasses/sunglasses while outsideb | 8,037 | 79 | 5,631 | 79 | 2,406 | 80 | |||
| Overall stress levelb,c | |||||||||
| 1 (lowest) | 2,525 | 25 | 1,696 | 24 | 829 | 28 | |||
| 2 | 2,073 | 20 | 1,424 | 20 | 649 | 22 | |||
| 3 | 2,140 | 21 | 1,539 | 21 | 601 | 20 | |||
| 4 | 1,667 | 16 | 1,210 | 17 | 457 | 15 | |||
| 5 | 1,005 | 10 | 750 | 10 | 255 | 9 | |||
| 6 | 493 | 5 | 350 | 5 | 143 | 5 | |||
| 7 (highest) | 260 | 3 | 200 | 3 | 60 | 2 | |||
| Ultraviolet light index | 4.5 (2.4–6.5) | 3.9 (2.1–6.2) | 5.5 (3.3–7.0) | ||||||
| Time spent outdoors, hours/weekb | |||||||||
| ≤7 | 7,169 | 71 | 7,169 | 100 | 0 | 0 | |||
| 8–14 | 1,742 | 17 | 0 | 0 | 1,742 | 58 | |||
| 15–21 | 668 | 7 | 0 | 0 | 668 | 22 | |||
| 22–28 | 265 | 3 | 0 | 0 | 265 | 9 | |||
| ≥29 | 319 | 3 | 0 | 0 | 319 | 11 | |||
Abbreviations: IQR, interquartile range; PW, person-weeks.
a Includes persons who reported their race/ethnicity as Asian (384 in total, 236 for ≤7 hours/week, and 148 for ≥8 hours/week) or Hispanic (281 in total, 201 for ≤7 hours/week, and 80 for ≥8 hours/week).
b Before data were carried forward, the following amounts of data were missing (percentage of weeks prior to recurrence, dropout, or end of study period): for use of contact lenses, 20.3%; for use of glasses/sunglasses, 26.7%; for overall stress, 21.5%; and for time spent outdoors, 20.1%.
c Stress was measured by asking, “In the past week, how stressed have you felt overall?” Participants could answer on a 7-point Likert scale.