Colleagues, I suspect I'm not the only one who has, over the years had the experience of spending a week (or more) on an analysis only to find important errors in the data set. I'm hoping for some feedback on what people do to try to find these errors (short of spending a week on an incorrect data set). To start the discussion, I've put on the Next Level web site (www.NextLevelSolns.com/downloads) an Excel macro that I've used, with some success to find errors. My experience is that most errors, at least those that are hard to find, are in the dosing specification. This macro makes histograms of:
Each covariate DVs Dose Amts Dose Times (after expanding the ADDL doses) Interdose interval (after expanding the ADDL doses) - time from each to the previous Dose to DV time (after expanding the ADDL doses) - time from each observation to the previous dose Currently this macro is limited to 12 covariates, could be increased easily if there is interest. It also isn't CMT specific, that is all doses are just listed, without regard to CMT, same with DVs. I might fix this someday. As usual, this is an entirely in my own self-interest, looking for better ways to find problems in data sets, so please give feedback or ideas. Mark
Data checking macro
2 messages
2 people
Latest: Sep 13, 2007
PDx-Pop 2.2 (and below) has an Excel macro that imports the data sets and
automatically gives the following plots:
DV vs ID, AMT (dose) vs ID, TIME vs ID, and DV vs TIME. The idea is to
graphically look for outliers in these plots.
PDx-Pop 3.0 (not yet released) also gives you the option to import the data
into R or S-Plus (your choice) and automatically create the above plots and
additionally individual plots of the DV vs TIME by ID.
Bill
_____
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Mark Sale - Next Level Solutions
Sent: Thursday, September 13, 2007 3:27 PM
Cc: [email protected]
Subject: [NMusers] Data checking macro
Colleagues,
I suspect I'm not the only one who has, over the years had the experience
of spending a week (or more) on an analysis only to find important errors in
the data set. I'm hoping for some feedback on what people do to try to find
these errors (short of spending a week on an incorrect data set). To start
the discussion, I've put on the Next Level web site
(www.NextLevelSolns.com/downloads) an Excel macro that I've used, with some
success to find errors. My experience is that most errors, at least those
that are hard to find, are in the dosing specification. This macro makes
histograms of:Each covariate
DVs
Dose Amts
Dose Times (after expanding the ADDL doses)
Interdose interval (after expanding the ADDL doses) - time from each to the
previous
Dose to DV time (after expanding the ADDL doses) - time from each
observation to the previous dose
Currently this macro is limited to 12 covariates, could be increased easily
if there is interest. It also isn't CMT specific, that is all doses are
just listed, without regard to CMT, same with DVs. I might fix this
someday.
As usual, this is an entirely in my own self-interest, looking for better
ways to find problems in data sets, so please give feedback or ideas.
Mark