Dear Janet,
I am not sure that tscale parameter would allow you to change the
observation time relative to the end-of-infusion time. As stated in the
manual, this parameter multiplies all rate constants (and only in linear
models). "The time scale parameter does not scale the duration parameter
D of a duration-modeled zero-order bolus dose." I assume it also does
not change RATE value. Thus, it may change rates (internal individual
times) but not the record times (or their relative positions).
Thanks
Leonid
--------------------------------------
Leonid Gibiansky, Ph.D.
President, QuantPharm LLC
web: www.quantpharm.com
e-mail: LGibiansky at quantpharm.com
tel: (301) 767 5566
On 6/3/2011 2:19 AM, Janet R. Wade wrote:
Dear Michael
I think you might want to use TSCALE (can also be written as XSCALE).
This PREDPP parameter lets you scale time, and you can also add an eta
(should you wish). The parameter is described in Guide VIII (Feb 2010).
With appropriate IF statements you should be able to scale the time
around the 1 hr time point only.
Kind regards
Janet
*From:*[email protected]
[mailto:[email protected]] *On Behalf Of *[email protected]
*Sent:* 02 June 2011 17:45
*To:* [email protected]
*Subject:* [NMusers] Modeling concentration data with imprecise sampling
time
All:
I have a data set following a constant rate 1-hour infusion where the
time of 1-hour sample is imprecise. In some cases the "1-hr" sample was
taken prior to infusion termination as it was intended; however, in
others it was quite apparently take after the infusion ended. I'm
thinking of modeling with the time of the "1-hr" sample as a "theta".
Does anyone have a NONMEM coding example showing how to do this? Any
other suggestions as to how to handle this would be appreciated as well.
Thanks,
Michael
