TABLE 1.
Repeated zone diameter measurements of three clinical isolates and three quality control strains by ruler, caliper, and Sirscan
| Isolate, reader(s), and method (n)a | Time (s), (mean ± SD) | Diam (mm, mean ± SD) of zone of inhibitionb | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| E. coli (CI) | FUR | KEF | AMP | GEN | SXT | FTX | IMP | AUG | FRX | MEZ | NOR | ATM | |
| J.C., ruler (5) | 39.4 ± 2.7 | 19.8 ± 0.4 | 17 ± 0 | 19 ± 0 | 18 ± 0 | 25.8 ± 0.4 | 28.8 ± 0.4 | 27.4 ± 0.5 | 19.6 ± 0.5 | 22 ± 0.9 | 24 ± 0 | 25.6 ± 0.8 | 28.6 ± 0.5 |
| S.M., caliper (5) | 26.2 ± 2.0 | 19.8 ± 0.4 | 17 ± 0 | 19.2 ± 0.4 | 18 ± 0.6 | 25.6 ± 0.5 | 28.8 ± 0.4 | 27.2 ± 0.4 | 19.4 ± 0.5 | 21.8 ± 0.4 | 24 ± 0 | 26 ± 0.6 | 28.4 ± 0.5 |
| 4 Techs, caliper (4) | 32 ± 6.0 | 19.8 ± 0.4 | 17.3 ± 0.4 | 19.5 ± 0.5 | 18.8 ± 1.3 | 26 ± 0 | 29.8 ± 0.8 | 28.3 ± 0.8 | 19.8 ± 0.8 | 22.3 ± 1.5 | 25 ± 0 | 27.3 ± 1.3 | 29 ± 1.6 |
| J.C., Sirscan (10) | 10.7 ± 0.6 | 20 ± 0 | 16.6 ± 0.5 | 19 ± 0 | 20.6 ± 0.7 | 27.7 ± 0.6 | 31.8 ± 0.4 | 27.7 ± 0.9 | 19 ± 0 | 22.2 ± 0.4 | 25.2 ± 0.4 | 31.9 ± 0.3 | 31.2 ± |
| M. morganii (CI) | KEF | AMP | GEN | SXT | FTX | IMP | FRX | MEZ | ATM | FOX | PIP | CIP | |
| J.C., ruler (5) | 37.2 ± 3.4 | 6 ± 0 | 6 ± 0 | 17. ± 0 | 22.2 ± 0.7 | 17 ± 0 | 19 ± 0.6 | 8 ± 0 | 11.2 ± 0.4 | 21.2 ± 1.2 | 16 ± 0 | 16 ± 0.6 | 28.4 ± 0.8 |
| S.M., caliper (5) | 26.2 ± 4.5 | 6 ± 0 | 6 ± 0 | 17 ± 0 | 22.2 ± 0.4 | 16.6 ± 0.5 | 19.2 ± 0.4 | 6.4 ± 0.8 | 12.4 ± 0.5 | 22 ± 0 | 16 ± 0 | 15.8 ± 0.4 | 27.6 ± 0.5 |
| 4 Techs, caliper (4) | 33 ± 6.7 | 6.3 ± 0.4 | 6 ± 0 | 17.3 ± 0.4 | 22.3 ± 1.3 | 17 ± 0 | 19.5 ± 0.5 | 7.5 ± 0.9 | 12 ± 0.7 | 23 ± 1.2 | 16.5 ± 0.5 | 16 ± 0.7 | 28.8 ± 2.3 |
| J.C., Sirscan (10) | 11 ± 0.6 | 6 ± 0 | 6 ± 0 | 17.7 ± 1.0 | 25.7 ± 1.9 | 17 ± 0 | 23.3 ± 0.5 | 6 ± 0 | 13.5 ± 0.7 | 24.2 ± 0.4 | 16.2 ± 0.4 | 16 ± 0 | 366 ± 2.2 |
| S. aureus (CI) | GEN | AUG | CIP | PEN | ERY | CLI | OXA | VAN | |||||
| J.C., ruler (5) | 27 ± 2.8 | 20.2 ± 0.4 | 26.6 ± 0.5 | 21 ± 0 | 14.0 ± 0 | 6 ± 0 | 23.6 ± 0.5 | 17.8 ± 0.4 | 18.8 ± 0.4 | ||||
| S.M., caliper (5) | 17.6 ± 1.2 | 20 ± 0 | 26 ± 0 | 21 ± 0 | 14.2 ± 0.4 | 6 ± 0 | 24 ± 0 | 18 ± 0 | 18.8 ± 0.4 | ||||
| 4 Techs, caliper (4) | 21.8 ± 5.4 | 20.5 ± 0.5 | 26.8 ± 0.8 | 22 ± 1.2 | 14.5 ± 0.5 | 6.5 ± 0.9 | 24 ± 0.7 | 18.8 ± 0.4 | 19.3 ± 0.8 | ||||
| J.C., Sirscan (10) | 11 ± 0.6 | 20.8 ± 0.4 | 27 ± 0 | 21.4 ± 0.5 | 14.6 ± 0.5 | 9.6 ± 0.5 | 27.2 ± 0.7 | 17.4 ± 0.5 | 18 ± 0 | ||||
| E. coli 25922 (QC) | KEF | AMP | GEN | SXT | FRX | IMP | FRX | MEZ | ATM | FOX | PIP | CIP | |
| L.S., caliper (6) | 22 ± 2.6 | 18.3 ± 0.5 | 19.7 ± 0.5 | 19 ± 0.6 | 25 ± 0.6 | 29.3 ± 0.9 | 25.7 ± 0.7 | 22.7 ± 0.5 | 24.7 ± 0.5 | 29.17 ± 1.1 | 25.3 ± 0.5 | 25 ± 0 | 31.5 ± 1.3 |
| 3 Techs, caliper (3) | 29 ± 5.1 | 17.3 ± 0.5 | 18.7 ± 0.9 | 19.3 ± 0.5 | 25 ± 0 | 29 ± 0 | 26 ± 0.8 | 21.7 ± 0.9 | 23.3 ± 0.5 | 29 ± 0.8 | 25.3 ± 0.5 | 25 ± 0.8 | 31.7 ± 0.5 |
| J.C., Sirscan (10) | 11.1 ± 0.3 | 17.2 ± 0.4 | 18.2 ± 0.4 | 21.8 ± 0.9 | 25 ± 0 | 31.9 ± 0.3 | 30.3 ± 0.5 | 22.3 ± 0.5 | 25.2 ± 0.4 | 31.9 ± 0.3 | 24.8 ± 0.6 | 27.2 ± 0.4 | 36 ± 0 |
| P. aeruginosa 27853 (QC) | GEN | SXT | IMP | MEZ | ATM | PIP | CIP | CHL | TOB | AMK | CAR | CAZ | |
| L.S., caliper (6) | 20.5 ± 1.0 | 18.3 ± 0.5 | 6 ± 0 | 23 ± 0.6 | 19.8 ± 0.7 | 25.3 ± 0.5 | 26.2 ± 0.4 | 25.5 ± 0.5 | 6 ± 0 | 20.8 ± 0.4 | 21.67 ± 0.5 | 19.5 ± 0.8 | 26.3 ± 0.5 |
| 3 Techs, caliper (3) | 29.7 ± 5.1 | 18 ± 0 | 6 ± 0 | 22.3 ± 0.5 | 20 ± 0 | 25 ± 0.8 | 26.3 ± 0.5 | 26 ± 1.4 | 6 ± 0 | 20.3 ± 0.5 | 21.7 ± 0.5 | 20 ± 0 | 26 ± 1.4 |
| J.C., Sirscan (10) | 11 ± 0 | 18.1 ± 0.3 | 6 ± 0 | 23 ± 0.6 | 20.1 ± 0.3 | 26 ± 0 | 28.9 ± 0.3 | 30.8 ± 0.6 | 6 ± 0 | 20.3 ± 0.6 | 21.8 ± 0.9 | 21.1 ± 0.3 | 27 ± 0 |
| S. aureus 25923 (QC) | GEN | SXT | AUG | CIP | PEN | ERY | CLI | EXA | VAN | ||||
| L.S., caliper (6) | 15.5 ± 1.3 | 22.5 ± 0.5 | 27.7 ± 0.5 | 30.8 ± 0.4 | 23.5 ± 0.8 | 34.7 ± 0.5 | 26.2 ± 0.4 | 25.7 ± 0.5 | 24.2 ± 0.4 | 18.8 ± 0.4 | |||
| 3 Techs, caliper (3) | 21 ± 2.4 | 20.6 ± 0.5 | 27.7 ± 0.5 | 30.3 ± 1.2 | 23.7 ± 0.9 | 33.7 ± 0.9 | 24.7 ± 0.9 | 24.3 ± 0.5 | 23 ± 0.8 | 17.7 ± 0.5 | |||
| J.C., Sirscan (10) | 11 ± 0 | 20.9 ± 0.3 | 29.6 ± 0.5 | 32.5 ± 0.5 | 25 ± 0 | 34 ± 0 | 27.1 ± 0.3 | 28.1 ± 0.5 | 24.4 ± 0.5 | 17 ± 0 | |||
a
Readers are indicated by initials. Techs, tchnicians; CI, clinical isolate; QC, quality control strain; n, number of reads.
b
FUR, nitrofurantoin; KEF, cephalothin; AMP, ampicillin; GEN, gentamicin; SXT, trimethoprim-sulfamethoxazole; FTX, cefotaxime; IMP, imipenem; AUG, amoxicillin-clavulanate; FRX, cefuroxime; MEZ, mezlocillin; NOR, norfloxacin; ATM, aztreonam; FOX, cefoxitin; PIP, piperacillin; CIP, ciprofloxacin; PEN, penicillin; ERY, erythromycin; CLI, clindamycin; OXA, oxacillin; VAN, vancomycin; CHL, chloramphenicol; TOB, tobramycin; AMK, amikacin; CAR, carbenicillin; CAZ, ceftazidime.