Characteristics of Participants at Baseline, by Study Group
| Characteristic | All n=719 | No Pill n=174 | Blinded to Placebo n=179 | Blinded to Echinacea n=184 | Open-Label Echinacea n=182 |
|---|---|---|---|---|---|
| a Belief in echinacea (expectancy) was assessed at baseline using a visual analogue scale ranging from 0 (totally ineffective) to 100 (extremely effective); only those with some experience with echinacea answered this question. | |||||
| Age, mean (SD), y | 33.7 (14.4) | 32.3 (14.2) | 33.2 (13.5) | 35.4 (15.3) | 33.9 (14.5) |
| Age, interquartile range, y | 21.5–41.8 | 20.8–43.4 | 21.3–43.5 | 21.5–46.5 | 21.7–46.5 |
| Female, % | 64.1 | 60.9 | 63.7 | 65.8 | 65.9 |
| Nonwhite, % | 12.1 | 13.8 | 12.3 | 14.1 | 8.2 |
| Current smoker, % | 12.8 | 14.4 | 11.2 | 14.1 | 11.6 |
| Household income ≤$25,000, % | 35.9 | 40.4 | 35.7 | 35.1 | 32.6 |
| At least some college, % | 84.0 | 84.0 | 85.6 | 80.0 | 86.4 |
| Belief in echinacea score [No. of participants], mean (SD)a | [219] 50.3 (20.6) | [53] 50.7 (21.4) | [48] 48.2 (21.5) | [57] 50.7 (20.5) | [61] 51.4 (19.4) |