# Select the maximum tolerated dose (MTD) for single agent trials

### Description

Select the maximum tolerated dose (MTD) when the single-agent trial is completed

### Usage

1 | ```
select.mtd(target, npts, ntox, cutoff.eli=0.95, extrasafe=FALSE, offset=0.05, print=TRUE)
``` |

### Arguments

`target` |
the target toxicity rate |

`npts` |
a vector containing the number of patients treated at each dose level |

`ntox` |
a vector containing the number of patients who experienced dose-limiting toxicity at each dose level |

`cutoff.eli` |
the cutoff to eliminate overly toxic doses for safety. We recommend
the default value of ( |

`extrasafe` |
set |

`offset` |
a small positive number (between 0 and 0.5) to control how strict the
stopping rule is when |

`print` |
to print out the dose selection result |

### Details

`select.mtd()`

selects the MTD based on isotonic estimates of toxicity
probabilities. `select.mtd`

selects as the MTD dose j*, for which the
isotonic estimate of the toxicity rate is closest to the target. If there
are ties, we select from the ties the highest dose level when the estimate
of the toxicity rate is smaller than the target, or the lowest dose level
when the estimate of the toxicity rate is greater than the target. The
isotonic estimates are obtained by the pooled-adjacent-violators algorithm
(PAVA) (Barlow, 1972).

### Value

`select.mtd()`

returns the MTD based on the trial data.

### Note

The MTD selection and dose escalation/deescalation rule are two independent components of the trial design. When appropriate, another dose selection procedure (e.g., based on a fitted logistic model) can be used to select the MTD after the completion of the trial using the BOIN design.

### Author(s)

Suyu Liu and Ying Yuan

### References

Liu S. and Yuan, Y. (2015). Bayesian Optimal Interval Designs for Phase I Clinical Trials, Journal of the Royal Statistical Society: Series C, 64, 507-523.

### See Also

Tutorial: http://odin.mdacc.tmc.edu/~yyuan/Software/BOIN/BOIN2.4_tutorial.pdf

Paper: http://odin.mdacc.tmc.edu/~yyuan/Software/BOIN/paper.pdf

### Examples

1 2 3 | ```
n<-c(3, 3, 15, 9, 0)
y<-c(0, 0, 4, 4, 0)
select.mtd(target=0.3, npts=n, ntox=y)
``` |