question archive Using an example from a study of adults with gastroesophageal reflux disease (GERD), symptoms of gastroesophageal reflux were examined over time (Dunbar, Agoston, Odze, Huo, Pham, Cipher, Castell, Genta, Souza, & Spechler, 2016)
Using an example from a study of adults with gastroesophageal reflux disease (GERD), symptoms of gastroesophageal reflux were examined over time (Dunbar, Agoston, Odze, Huo, Pham, Cipher, Castell, Genta, Souza, & Spechler, 2016)
Subject:StatisticsPrice: Bought3
Using an example from a study of adults with gastroesophageal reflux disease (GERD), symptoms of gastroesophageal reflux were examined over time (Dunbar, Agoston, Odze, Huo, Pham, Cipher, Castell, Genta, Souza, & Spechler, 2016). Adults with GERD were followed over a period of two weeks while being required to be free of all proton-pump inhibitor medications (the "intervention"). A subset of these data (n = 10) are presented in HW6.sav. One of the dependent variables was esophageal reflux symptoms (measured by the GERD Health Related Quality of Life Questionnaire) where lower numbers are more desirable and indicative of healthy esophageal functioning and higher numbers are indicative of more GERD symptoms. For this example, the null hypothesis is: There is no change in esophageal reflux symptoms from baseline to follow-up for patients with GERD.
These data are presented in HW6.sav.
Download the file:
HW6.sav
Open in SPSS. Use the dataset to answer the following questions.
Compute a paired samples t-test with baseline and post-treatment esophageal impedance scores.
-List numerator value. (Hint: No hand calculations are required for Q1 and 2. The values are found in the output.)
-List the denominator value. To help with your calculations: the standard deviation of the difference scores = 1.31
-Compute the t-test from above using SPSS. Paste the table containing the t value into your homework.
-Is the t significant at a=0.05? Specify how you arrived at your answer.
-What is the exact likelihood of obtaining the calculated t value at least as extreme or as close to the one that was actually observed, assuming that the null hypothesis is true?
-Write interpretation of the results of the paired samples t-test.
Help with Homework 6:
Q4: either compare the obtained t to the tabled t (specify the tabled t value), or compare the obtained p to an alpha of .05 (specify the obtained p value).
===================================================================
Paired Samples Statistics
Mean N Std. Deviation Std. Error Mean
GERD-HRQL Questionnaire Score, 2.0627 10 1.95654 .61871
Baseline Transformed
GERD-HRQL Questionnaire 3.3257 10 1.30784 .41357
Score, 2-Week Transformed
=====================================================
Paired Samples Correlations
N Correlation Sig.
Pair 1 GERD-HRQL Questionnaire Score, 10 .747 .013
Baseline Transformed
No more information to add here
===================================================================
Paired Samples Test
Paired Differences t df Sig. (2-tailed) Mean Std. Deviation Std. Error Mean
-3.050 9 .014 -1.26304 1.30970 .41416
Mean 95% Confidence Interval of the Difference
Lower Upper
-2.19995 -.32614
