st: Reconstructing the distribution from interval data

[Ronan Conroy <rconroy@rcsi.ie>]

I'm reviewing a paper in which doctors were asked how many times they  
had carried out a particular procedure in the last year. The  
questionnaire used categories, so responses looked like this:
Number of  Gynaecologists Plastic
times                     Surgeons

None           17           3
1-5            24           34
5-10            0           4
10-20           0           1
More than 20    0           1

I am wondering how one might calculate the likeliest underlying annual  
rate for each group based on the data above.
Has anyone come up against this problem and found a solution? I'd be  
very curious about the answer for practical reasons - the authors have  
data that are pretty hard to come by, and being able to calculate an  
annual rate would be very helpful indeed for future research.



Ronán Conroy
Associate Professor
Division of Population Health Sciences
=================================

rconroy@rcsi.ie
Royal College of Surgeons in Ireland
Epidemiology Department,
Beaux Lane House, Dublin 2, Ireland
+353 (0)1 402 2431
+353 (0)87 799 97 95
+353 (0)1 402 2764 (Fax - remember them?)
http://rcsi.academia.edu/RonanConroy

P    Before printing, think about the environment





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