Date: Tue, 14 Jan 2003 15:47:41 -0500
Reply-To: "Burleson,Joseph A." <email@example.com>
Sender: "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From: "Burleson,Joseph A." <firstname.lastname@example.org>
Subject: Re: Repeated measures
Content-Type: text/plain; charset="iso-8859-1"
Use GLM. One between-subjects variable (Treatment), one within-subjects
variable (time). Look at the Time X Treatment interaction. If it is sig, one
group improved more than the other.
From: Bautista Christian [mailto:cbautista@NMRCD.MED.NAVY.MIL]
Sent: Tuesday, January 14, 2003 8:19 AM
Subject: Repeated measures
I have a trial study where there are two groups (placebo and intervention).
STEP 1. At the beginning of the study I have collected a quantitative
measure (weight) for each participant in each group.
STEP 2. Then, we have given a special diet for all participants of the
intervention group and a normal diet for the place group.
STEP 3. After 10 days we have measured their weigth again for all
participant in each group.
a) Apply paired-samples t-test to evaluate the difference OF WEIGHT
(before-after) in each group separately.
I need to know if there is a difference of weight between both groups.
What statistical test I have to use?
I was thinking in General Lineal Model for repeated measures but I have only
I migth calculate the difference of weight (before-after) for each group and
then to evaluate this difference using a simple Student t test.
Thanks in advance,