Table 3.
Phase II OptiSafe test method accuracy within each laboratory: EPA and GHS classification systems
| Lead Laboratory – OptiSafe classification | naïve Laboratory 1 – OptiSafe classification | naïve Laboratory 2 – OptiSafe classification | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| + | − | Total | + | − | Total | + | − | Total | ||
| EPA in vivo classification | + | 13 | 0 | 13 | 14 | 0 | 14 | 13 | 1 | 14 |
| − | 3 | 9 | 12 | 5 | 8 | 13 | 3 | 10 | 13 | |
| Total | 16 | 9 | 25a | 19 | 8 | 27b | 16 | 11 | 27b | |
| Accuracy = 88% | Accuracy = 82% | Accuracy = 85% | ||||||||
| Negative predictivity = 100% | Negative predictivity = 100% | Negative predictivity = 91% | ||||||||
| Positive predictivity = 81% | Positive predictivity = 74% | Positive predictivity = 81% | ||||||||
| Prevalence = 52% | Prevalence = 52% | Prevalence = 52% | ||||||||
| Sensitivity = 100% | Sensitivity = 100% | Sensitivity = 93% | ||||||||
| Specificity = 75% | Specificity = 62% | Specificity = 77% | ||||||||
| False Positive Rate = 25% | False Positive Rate = 39% | False Positive Rate = 23% | ||||||||
| False Negative Rate = 0% | False Negative Rate = 0% | False Negative Rate = 7% | ||||||||
| Lead Laboratory – OptiSafe classification | naïve Laboratory 1 – OptiSafe classification | naïve Laboratory 2 – OptiSafe classification | ||||||||
| + | − | Total | + | − | Total | + | - | Total | ||
| GHS In vivo classification | + | 12 | 0 | 12 | 13 | 0 | 13 | 11 | 2 | 13 |
| − | 3 | 10 | 13 | 5 | 9 | 14 | 4 | 10 | 14 | |
| Total | 15 | 10 | 25a | 18 | 9 | 27b | 15 | 12 | 27b | |
| Accuracy = 88% | Accuracy = 82% | Accuracy = 78% | ||||||||
| Negative predictivity = 100% | Negative predictivity = 100% | Negative predictivity = 83% | ||||||||
| Positive predictivity = 80% | Positive predictivity = 72% | Positive predictivity = 73% | ||||||||
| Prevalence = 48% | Prevalence = 48% | Prevalence = 48% | ||||||||
| Sensitivity = 100% | Sensitivity = 100% | Sensitivity = 85% | ||||||||
| Specificity = 77% | Specificity = 64% | Specificity = 71% | ||||||||
| False Positive Rate = 23% | False Positive Rate = 36% | False Positive Rate = 29% | ||||||||
| False Negative Rate = 0% | False Negative Rate = 0% | False Negative Rate = 15% | ||||||||
+ = chemical identified as an EPA or GHS ocular corrosive or irritant (EPA Categories I, II or III; GHS Categories 1 or 2); − = chemical not identified as an EPA or GHS ocular corrosive or irritant (EPA Category IV; GHS Category NC)
Calculations for 25 chemicals. Results were excluded for 4,4-Methylene bis-(2,6-di-tert-butyl)phenol because it produced a response exceeding the upper range of the spectrophotometer and 3,3-dithiodipropionic acid because it was evaluated with a protocol not included in the validation study design. Benzalkonium chloride (5%), sodium lauryl sulfate (3%), and cetyl pyridinium bromide (0.1%) were not tested in the main protocol because they were identified as foaming agents in the pre-screen.
Calculations for 27 chemicals. Benzalkonium chloride (5%), sodium lauryl sulfate (3%), and cetyl pyridinium bromide (0.1%) were not tested in the main protocol because they were identified as foaming agents in the pre-screen.