Table 1. Characteristics of the Study Populationa.
| All Employees, No. (%) | |||
|---|---|---|---|
| Treatment Worksites (n = 4037) | Primary Control Worksites (n = 4106) | Primary and Secondary Control Worksites (n = 28 937) | |
| Demographic Characteristics | |||
| Age, mean (SD), y | 38.8 (0.7) | 38.3 (0.5) | 38.7 (0.2) |
| Sex, % | |||
| Male | 2104 (53.7) | 2151 (54.5) | 15 597 (54.2) |
| Female | 1933 (46.3) | 1955 (45.5) | 13 339 (45.8) |
| Race/ethnicity, % | |||
| Black | 797 (19.8) | 1004 (20.1) | 7218 (20.7) |
| White | 2601 (56.3) | 2203 (57.9) | 14 754 (55.3) |
| Hispanic | 402 (17.9) | 720 (17.1) | 5161 (17.8) |
| Other | 237 (6.0) | 179 (5.0) | 1803 (6.2) |
| Stably Employed Subsample (n = 1892) | Stably Employed Subsample (n = 1930) | Stably Employed Subsample (n = 13 452) | |
| Employment Characteristicsb | |||
| Worker type, % | |||
| Full-time salaried | 232 (15.5) | 222 (15.2) | 1605 (16.4) |
| Full-time hourly | 700 (44.9) | 743 (47.0) | 5113 (46.2) |
| Part-time hourly | 960 (39.6) | 965 (37.8) | 6734 (37.4) |
| Annual earnings, mean (SD), $ | |||
| Full-time salaried | 49 340 (1116.8) | 47 669 (698.4) | 48 467 (298.7) |
| Full-time hourly | 25 727 (682.6) | 24 528 (436.1) | 25 296 (173.8) |
| Part-time hourly | 10 301 (180.5) | 9981 (100.7) | 10 034 (48.2) |
| Job category, % | |||
| Sales workers | 720 (34.3) | 741 (32.5) | 5085 (31.9) |
| Laborers/helpers | 345 (20.1) | 351 (20.6) | 2495 (20.6) |
| Operative workersc | 309 (16.1) | 291 (15.4) | 2063 (15.9) |
| Service workers | 225 (11.6) | 254 (13.1) | 1688 (12.1) |
| Mid-level officials | 184 (11.5) | 172 (11.4) | 1262 (12.4) |
| Administrative support | 70 (4.3) | 71 (4.4) | 570 (5.1) |
| Other | 39 (2.0) | 50 (2.6) | 289 (2.0) |
| Employer-sponsored insuranced | |||
| Ever enrolled in 2014, % | 762 (50.0) | 748 (50.1) | 5052 (48.3) |
| Months enrolled in 2014, mean | 11.5 | 11.5 | 11.5 |
All individuals were assigned to treatment or control status based on the first worksite in which they appeared during the treatment period. Characteristics were weighted by exposure to the wellness program based on duration of employment and hours worked and a weight that balances treatment and control on demographics. Age was defined as of December 2014, the year before the intervention.
Employment characteristics were derived from the stably employed subsample and measured at the time of an individual’s first appearance in the data.
The operative workers category included cake decorator, stock/cart retriever, gas station team member, bakery clerk, bakery supervisor, meat clerk or cutter, deli supervisor or clerk, produce clerk, merchandise specialist, order picker packer, order forklift driver, order fulfillment specialist, produce inspector, pallet forklift operator, and lead storage forklift operator.
BJ’s Wholesale Club, a self-insured employer, offered employer-sponsored health insurance through a third-party administrator, Cigna. Enrollment data were taken from 2014, the year before the intervention. About half of stably employed employees and a third of all employees were enrolled in Cigna.