| Model | Number of parameters | Log‐likelihood | AIC | BMD30 a | BMDL30 a | BMDU30 a | Converged | Accepted AIC |
|---|---|---|---|---|---|---|---|---|
| Null | 1 | −119.66 | 241.32 | NA | NA | NA | Yes | |
| Full | 6 | −38.90 | 89.80 | NA | NA | NA | Yes | |
| Logistic | 2 | −40.32 | 84.64 | 501.48 | 447.86 | 553.76 | Yes | Yes |
| Probit | 2 | −39.63 | 83.26 | 473.57 | 423.56 | 525.77 | Yes | Yes |
| Log‐logistic | 3 | −38.95 | 83.90 | 406.60 | 344.26 | 472.04 | Yes | Yes |
| Log‐probit | 3 | −38.90 | 83.80 | 390.94 | 335.64 | 447.35 | Yes | Yes |
| Weibull | 3 | −39.00 | 84.00 | 442.09 | 375.50 | 506.25 | Yes | Yes |
| Gamma | 3 | −38.92 | 83.84 | 411.12 | 353.44 | 468.78 | Yes | Yes |
| Two‐stage | 3 | −41.12 | 88.24 | 382.65 | 335.35 | 440.72 | No | No |
AIC: Akaike information criterion; BMD: benchmark dose; BMDL: benchmark dose lower confidence limit; BMDU: benchmark dose upper confidence limit.
a
results expressed as μg/kg bw per day.