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RE: Data checking macro

From: Bill Bachman <bachmanw>
Date: Thu, 13 Sep 2007 16:35:41 -0400

Mark,

 

Ok with me to add any of those suggested plots! I may add your covariate
histograms to our scripts! I will probably add statistical summaries of all
data items to the R and S-Plus scripts (a simple one liner).

 

Perhaps some type of plots by time after dose (TAD) plots may have helped in
your situation? We have automated a variety of TAD plots for the output
table files (but not for the data checkout plots yet).

 

Bill

 

  _____

From: owner-nmusers
Behalf Of Mark Sale - Next Level Solutions
Sent: Thursday, September 13, 2007 4:13 PM
Cc: nmusers
Subject: RE: [NMusers] Data checking macro

 

Thanks Bill,
 I'll consider adding those (if Icon doesn't object). But, my experience is
that errors in DV (value) are not too hard to find. My single biggest
time-wasting exercise (about 3 weeks) involved a very complex dosing scheme,
several drugs, from several studies, several files, > 1000 subjects (so
individual plots by ID was not very practical) with an II of 12 when it
should have been 24, due to a slight difference in how the source data file
was formatted. The interdose interval (and the last dose-to-dv interval)
would have pickup it up.

Mark


Mark Sale MD
Next Level Solutions, LLC
www.NextLevelSolns.com
919-846-9185






-------- Original Message --------
Subject: RE: [NMusers] Data checking macro
From: Bill Bachman <bachmanw
Date: Thu, September 13, 2007 3:48 pm
To: "'Mark Sale - Next Level Solutions'" <mark
Cc: <nmusers

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 p! lots of the DV vs TIME by ID.

 

Bill

 

  _____

From: owner-nmusers
On Be half Of Mark Sale - Next Level Solutions
Sent: Thursday, September 13, 2007 3:27 PM
Cc: nmusers
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.NextLevelSol!
ns.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


Received on Thu Sep 13 2007 - 16:35:41 EDT

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