TABLE 2.
Proficiency panel results of the QC-2010 and QC-2012 samples
| Yr of analysis and code | NRC proficiency panelsa |
Results for IS481 or IS1001 detection by laboratoriesb |
||||
|---|---|---|---|---|---|---|
| Sample | Ctc | No. of positive/total answersd | Mean Cte (no. of samples) | Ct interval | Ct CV (%) | |
| 2010 | ||||||
| QC10-1 | Water | Undet | 1/33 | 34 (1) | NA | NA |
| QC10-2 | B. pertussis 10 pg/μl | 22 | 33/33 | 21 (30) | 14–32 | 18 |
| QC10-3 | B. parapertussis 1pg/μl | 25 | 18/18 | 25 (16) | 19–36 | 15 |
| QC10-4 | Water | Undet | 1/33 | 40 (1) | NA | NA |
| QC10-5 | B. pertussis 0.1 pg/μl | 28 | 33/33 | 27 (30) | 21–38 | 13 |
| QC10-6 | B. holmesii 10 pg/μl | 23 | 33/33 | 22 (30) | 15–32 | 18 |
| 2012 | ||||||
| QC12-1 | B. holmesii 10 pg/μl | 23 | 34/35 | 22 (33) | 20–28 | 8 |
| QC12-2 | B. parapertussis 0.1 pg/μl | 29 | 24/27 | 31 (23) | 29-41 | 9 |
| QC12-3 | B. bronchiseptica 100 pg/μl | 26 | 32/35 | 26 (31) | 23–36 | 11 |
| QC12-4 | B. pertussis 0.01 pg/μl | 31 | 32/35 | 31 (31) | 28–37 | 6 |
| QC12-5 | Water | Undet | 2/35 | 39 (2) | NA | NA |
| QC12-6 | B. pertussis 1 pg/μl | 23 | 35/35 | 24 (34) | 20–28 | 8 |
a
Ct, cycle threshold; undet, undetermined.
b
CV, coefficient of variation (ratio of the standard deviation to the mean of the Ct values); NA, not applicable.
c
Average Ct of at least two replicates.
d
The laboratory using endpoint PCR method (n = 1) is only included in the positive/total answers.
e
Mean and interval of Ct calculated with the values reported by the participating laboratories.