Table 1.
Baseline Characteristics of the Participants in the Per-Protocol Population.*
| Characteristic | All Participants (N = 310) | Azithromycin (N = 155) | Doxycycline (N = 155) | P Value† |
|---|---|---|---|---|
| All participants | ||||
| Sex — no. (%) | 0.74 | |||
| Male | 201 (65) | 102 (66) | 99 (64) | |
| Female | 109 (35) | 53 (34) | 56 (36) | |
| Race — no./total no. (%) | 0.49 | |||
| White | 109/307 (36) | 59/154 (38) | 50/153 (33) | |
| Black | 136/307 (44) | 64/154 (42) | 72/153 (47) | |
| Other | 62/307 (20) | 31/154 (20) | 31/153 (20) | |
| Hispanic ethnic background — no. (%) | 158 (51) | 84 (54) | 74 (48) | 0.09 |
| Median age (range) — yr | 17.0 (13.5-20.4) | 17.1 (14.6-18.9) | 16.9 (13.5-20.4) | 0.07 |
| Previous chlamydia infection — no. (%) | 0.71 | |||
| No | 222 (72) | 113 (73) | 109 (70) | |
| Yes | 88 (28) | 42 (27) | 46 (30) | |
| HIV or AIDS — no. (%) | NA | |||
| Not present | 309/310 (100) | 154/155 (99) | 155/155 (100) | |
| Information not ascertained | 1/310 (<1) | 1/155 (1) | 0 | |
| Median no. of sexual partners in the previous 12 mo (IQR) | 3 (2-6) | 3 (2-6) | 3 (2-6) | 0.57 |
| Median age at first sexual activity (IQR) — yr | 14 (13-14) | 14 (13-15) | 13 (13-14) | 0.04 |
| Male participants | ||||
| Painful urination — no./total no. (%) | 0.86 | |||
| No | 160/201 (80) | 82/102 (80) | 78/99 (79) | |
| Yes | 41/201 (20) | 20/102 (20) | 21/99 (21) | |
| Penile discharge — no./total no. (%) | >0.99 | |||
| No | 191/201 (95) | 97/102 (95) | 94/99 (95) | |
| Yes | 10/201 (5) | 5/102 (5) | 5/99 (5) | |
| Pain in the scrotum or testicle area — no./total no. (%) | ||||
| No | 199/201 (99) | 100/102 (98) | 99/99 (100) | 0.50 |
| Yes | 2/201 (1) | 2/102 (2) | 0 | |
| No previous nongonococcal urethritis — no./total no. (%) | 201/201 (100) | 102/102 (100) | 99/99 (100) | NA |
| No previous epididymitis — no./total no. (%) | 201/201 (100) | 102/102 (100) | 99/99 (100) | NA |
| Female participants | ||||
| Painful urination — no./total no. (%) | >0.99 | |||
| No | 102/109 (94) | 50/53 (94) | 52/56 (93) | |
| Yes | 7/109 (6) | 3/53 (6) | 4/56 (7) | |
| Abnormal vaginal discharge — no./total no. (%) | 0.85 | |||
| No | 55/109 (50) | 26/53 (49) | 29/56 (52) | |
| Yes | 54/109 (50) | 27/53 (51) | 27/56 (48) | |
| Irregular vaginal bleeding — no./total no. (%) | >0.99 | |||
| No | 97/109 (89) | 47/53 (89) | 50/56 (89) | |
| Yes | 12/109 (11) | 6/53 (11) | 6/56 (11) | |
| Pelvic pain — no./total no. (%) | 0.12 | |||
| No | 83/109 (76) | 44/53 (83) | 39/56 (70) | |
| Yes | 26/109 (24) | 9/53 (17) | 17/56 (30) | |
| Previous pelvic inflammatory disease — no./total no. (%) | 0.23 | |||
| No | 107/109 (98) | 51/53 (96) | 56/56 (100) | |
| Yes | 2/109 (2) | 2/53 (4) | 0 | |
| Hormone contraception use — no./total no. (%) | >0.99 | |||
| No | 100/109 (92) | 49/53 (92) | 51/56 (91) | |
| Yes | 9/109 (8) | 4/53 (8) | 5/56 (9) | |
*
All characteristics, with the exception of the sex of the participants, were self-reported. AIDS denotes acquired immunodeficiency syndrome, HIV human immunodeficiency virus, IQR interquartile range, and NA not applicable.
†
P values for the differences between the two treatment groups were determined with the use of a Wilcoxon rank-sum test (for age, sex partners in the past 12 months, and age at first sex) or Fisher's exact test (for all other characteristics).