Patient characteristics, allergy status and indication for therapy
| Characteristic* | All patients, n=1497 | Reported penicillin allergy, n=240 | No reported penicillin allergy, n=1257 | P value† |
| Age, years median (IQR) | 73 (56–82) | 73 (55–84) | 73 (55–84) | 0.745 |
| Sex, female | 752 (50.2) | 144 (60) | 602 (48) | 0.001 |
| Specialty | ||||
| Medicine | 683 (45.6) | 109 (45.4) | 574 (45.6) | 0.944 |
| Acute medicine | 295 (19.7) | 49 (20.4) | 246 (19.5) | 0.763 |
| Elderly medicine | 153 (10.2) | 23 (9.6) | 130 (10.3) | 0.029 |
| Specialist surgical | 265 (17.7) | 42 (17.5) | 223 (17.7) | <0.001 |
| General surgical | 94 (6.3) | 16 (6.7) | 78 (6.2) | 0.787 |
| Private | 7 (0.5) | 1 (0.4) | 6 (0.5) | 1.000 |
| Antibiotic allergies/adverse drug reaction | 165 (11) | 83 (34.6) | 82 (6.5) | <0.001 |
| Macrolides | 39 (2.6) | 21 (8.8) | 18 (1.4) | <0.001 |
| Trimethoprim | 27 (1.8) | 15 (6.3) | 12 (1) | <0.001 |
| Quinolones | 25 (1.7) | 13 (5.4) | 12 (1) | <0.001 |
| Nitrofurantoin | 18 (1.2) | 9 (3.8) | 9 (0.7) | <0.001 |
| Sulfonamides | 17 (1.1) | 6 (2.5) | 11 (0.9) | 0.029 |
| Tetracyclines | 7 (0.5) | 4 (1.7) | 3 (0.2) | 0.015 |
| Glycopeptide | 7 (0.5) | 1 (0.4) | 6 (0.5) | 0.688 |
| Cephalosporins | 7 (0.5) | 5 (2.1) | 2 (0.2) | 0.002 |
| Metronidazole | 6 (0.4) | 3 (1.3) | 3 (0.2) | 0.056 |
| Meropenem | 5 (0.3) | 4 (1.7) | 1 (0.1 | 0.003 |
| Clindamycin | 4 (0.3) | 1 (0.4) | 3 (0.2) | 0.503 |
| Aminoglycoside | 3 (0.2) | 1 (0.4) | 2 (0.2) | 0.408 |
| Indications for antibiotic treatment | ||||
| Community-acquired pneumonia | 495 (33.1) | 73 (30.4) | 422 (33.6) | 0.341 |
| Urinary tract infection | 407 (27.2) | 64 (26.7) | 343 (27.3) | 0.843 |
| Hospital-acquired pneumonia | 330 (22) | 55 (22.9) | 275 (21.9) | 0.143 |
| Bacterial skin and soft tissue infection | 265 (17.7) | 50 (20.8) | 215 (17.1) | 0.165 |
*Data reported as n (%) unless otherwise stated.
†Independent samples t-test or a two-sample test of proportions as appropriate.