Hello all,

I was runing some analysis here and found an error with epitools::oddsratio.
First I tought it was in my data, later I tought I was running the function
incorrectly but I now realize that there is something with numbers close to
zero or cells with zero...

below the same error with a simulated data... but it happens exactly the
same with mine wich has one cell with 1.

> m<-matrix(c(360,7,0,120),byrow=F,nrow=2,ncol=2)
> m
     [,1] [,2]
[1,]  360    0
[2,]    7  120
> oddsratio(m)
Erro em uniroot(function(or) { :
  f() values at end points not of opposite sign

> m<-matrix(c(360,7,4,120),byrow=F,nrow=2,ncol=2)
> m
     [,1] [,2]
[1,]  360    4
[2,]    7  120
> oddsratio(m)
Erro em uniroot(function(or) { :
  f() values at end points not of opposite sign

> m<-matrix(c(360,7,7,120),byrow=F,nrow=2,ncol=2)
> m
     [,1] [,2]
[1,]  360    7
[2,]    7  120
> oddsratio(m)
$data
          Outcome
Predictor  Disease1 Disease2 Total
  Exposed1      360        7   367
  Exposed2        7      120   127
  Total         367      127   494

$measure
          odds ratio with 95% C.I.
Predictor  estimate    lower upper
  Exposed1   1.0000       NA    NA
  Exposed2 806.1128 300.7302  2560

$p.value
          two-sided
Predictor  midp.exact fisher.exact   chi.square
  Exposed1         NA           NA           NA
  Exposed2          0 1.896808e-96 4.400778e-94

Is it impoossible to estimate OR confidence intervals with tables with very
low numbers? Any work around sugestions?

Abraço forte e que a força esteja com você,

Dr. Pedro Emmanuel A. A. do Brasil
Instituto de Pesquisa Clínica Evandro Chagas
Fundação Oswaldo Cruz
Rio de Janeiro - Brasil

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