{smcl} {* *! version 1.0 14 Jul 2020}{...} {vieweralsosee "" "--"}{...} {vieweralsosee "Install command2" "ssc install command2"}{...} {vieweralsosee "Help command2 (if installed)" "help command2"}{...} {viewerjumpto "Syntax" "mtpi##syntax"}{...} {viewerjumpto "Description" "mtpi##description"}{...} {viewerjumpto "Options" "mtpi##options"}{...} {viewerjumpto "Remarks" "mtpi##remarks"}{...} {viewerjumpto "Examples" "mtpi##examples"}{...} {title:Title} {phang} {bf:mtpi} {hline 2} A command for the modified Toxicity Probability Interval design {marker syntax}{...} {title:Syntax} {p 8 17 2} {cmdab:mtpi} [{help varlist}] [{cmd:,} {it:options}] {synoptset 20 tabbed}{...} {synopthdr} {synoptline} {syntab:Optional} {synopt:{opt ep1(#)}} specifies the lower bound of the interval around the TTL that is safe. {pstd} {p_end} {synopt:{opt ep2(#)}} specifies the upper bound of the interval around the TTL that is safe. {pstd} {p_end} {synopt:{opt safe1(#)}} specifies the safety cutoff for declaring the lowest dose to be safe. {pstd} {p_end} {synopt:{opt safe2(#)}} specifies the safety cutoff for declating the dose to be safe. {pstd} {p_end} {synopt:{opt ttl(#)}} specifies the target toxicity level that defines the maximum tolerated dose. {pstd} {p_end} {synopt:{opt simn(#)}} specifes the number of simulations used {pstd} {p_end} {synopt:{opt sampsize(#)}} specifies the sample size of each trial in the simulations. {pstd} {p_end} {synopt:{opt csize(#)}} specifies the cohort size used in the trial. {pstd} {p_end} {synopt:{opt startdose(#)}} specifies the starting dose. {pstd} {p_end} {synopt:{opt priora(#)}} specifies the a parameter of the prior Beta distribution. {pstd} {p_end} {synopt:{opt priorb(#)}} specifies the a parameter of the prior Beta distribution. {pstd} {p_end} {synopt:{opt truep(numlist ascending >=0 <=1)}} specifies a vector of true probabilities of DLT for each dose level. {pstd} {p_end} {synopt:{opt decisiontable}} specifies that the single cohort decision rules be displayed as a lookup table. {pstd} {p_end} {synoptline} {p2colreset}{...} {p 4 6 2} {marker description}{...} {title:Description} {pstd} {pstd} The modified Toxicity Probability Interval design is an attempt to implement a method that is as simple as a 3+3 decision but based on statistical distributions rather than a pure rule-based approach. This method produces decision making tables for the fully trial so a statistician need not be involved in all the dose escalation decisions. {pstd} The command {cmd:mtpi} performs simulations to find the operating characteristics alongside the decision matrix given a sample size and number of DLTs. {marker options}{...} {title:Options} {dlgtab:Main} {phang} {opt ep1(#)} specifies the lower bound of the interval around the TTL that is safe. {pstd} {p_end} {phang} {opt ep2(#)} specifies the upper bound of the interval around the TTL that is safe. {pstd} {p_end} {phang} {opt safe1(#)} specifies the safety cutoff for declaring the lowest dose to be safe. {pstd} {p_end} {phang} {opt safe2(#)} specifies the safety cutoff for declating the dose to be safe. {pstd} {p_end} {phang} {opt ttl(#)} specifies the target toxicity level that defines the maximum tolerated dose. {pstd} {p_end} {phang} {opt simn(#)} specifes the number of simulations used {pstd} {p_end} {phang} {opt sampsize(#)} specifies the sample size of each trial in the simulations. {pstd} {p_end} {phang} {opt csize(#)} specifies the cohort size used in the trial. {pstd} {p_end} {phang} {opt startdose(#)} specifies the starting dose. {pstd} {p_end} {phang} {opt priora(#)} specifies the a parameter of the prior Beta distribution. {pstd} {p_end} {phang} {opt priorb(#)} specifies the a parameter of the prior Beta distribution. {pstd} {p_end} {phang} {opt truep(numlist ascending >=0 <=1)} specifies a vector of true probabilities of DLT for each dose level. {pstd} {p_end} {phang} {opt decisiontable} specifies that the single cohort decision rules be displayed as a lookup table. {pstd} {p_end} {marker examples}{...} {title:Examples} {pstd} {pstd} The basic command will do a simulation {pstd} {stata mtpi} {pstd} The results show a table of each dose level with the true probabilities of a DLTs and the proportion of time those doses are recommended, experimented on and how many DLTs were observed on average. {title:References} {pstd} {pstd} Yuan Ji, Ping Liu, Yisheng Li and NB Bekele (2010) A modified toxicity probability interval method for dose-finding trials. Clin. Trials 7(6) 653-663. {title:Author} {p} Prof Adrian Mander, Cardiff University. Email {browse "mailto:mandera@cardiff.ac.uk":mandera@cardiff.ac.uk} {title:See Also} Related commands: {help crm} (if installed) {stata ssc install crm} (to install this command)