1 SPSS 201: Using SPSS to Perform Commonly Used Statistical Testing in Medical Research (Workshop)...
-
Upload
marsha-pearson -
Category
Documents
-
view
226 -
download
0
Transcript of 1 SPSS 201: Using SPSS to Perform Commonly Used Statistical Testing in Medical Research (Workshop)...
11
SPSS 201: Using SPSS to SPSS 201: Using SPSS to Perform Commonly Used Perform Commonly Used
Statistical Testing in Medical Statistical Testing in Medical Research (Workshop) Research (Workshop)
Dr. Daisy DaiDr. Daisy Dai
Department of Medical Department of Medical ResearchResearch
22
Who are biostatisticians?Who are biostatisticians?
Ashley ShermanAshley Sherman
Phone: 816-701-1347Phone: 816-701-1347 [email protected]@cmh.edu
Daisy DaiDaisy Dai
Phone: 816-701-5233Phone: 816-701-5233 Email: Email: [email protected]@cmh.edu
ConsultationConsultation Experimental design Experimental design
and sampling planand sampling plan Collaboration in Collaboration in
presentation and presentation and publication of publication of studiesstudies
EducationEducation ResearchResearch
33
Statistical Courses Statistical Courses
SPSS 201: Using SPSS to SPSS 201: Using SPSS to perform statistical tests Iperform statistical tests I
SPSS 202: Using SPSS to SPSS 202: Using SPSS to perform statistical tests IIperform statistical tests II
SPSS 204: Using SPSS to SPSS 204: Using SPSS to manage datamanage data
SPSS 203: Summarize data SPSS 203: Summarize data with tables and graphswith tables and graphs
STA 101: Properly Setting STA 101: Properly Setting up and Designing a Clinical up and Designing a Clinical Research Study Including Research Study Including Power Analysis for Proper Power Analysis for Proper Patient Numbers (July 16Patient Numbers (July 16thth))
STA 102: Commonly Used STA 102: Commonly Used
Statistical Tests in Medical Statistical Tests in Medical Research - Part IResearch - Part I
STA 103: Commonly Used STA 103: Commonly Used Statistical Tests in Medical Statistical Tests in Medical Research - Part IIResearch - Part II
44
ContentsContents
Review statistical tools (1 hour)Review statistical tools (1 hour) Introduce SPSS (30 minutes)Introduce SPSS (30 minutes) Practice (1 hour)Practice (1 hour) Questions and discussions ( 30 Questions and discussions ( 30
minutes) minutes)
55
Statistical toolsStatistical tools
66
Medical ResearchMedical Research
Clinical TrialsClinical Trials Intervention or therapeuticIntervention or therapeutic PreventativePreventative
Retrospective StudiesRetrospective Studies
77
DataData
Medical dataMedical data Physics dataPhysics data Chemistry dataChemistry data EducationEducation EconomicsEconomics Social studiesSocial studies SensorySensory NutritionNutrition Many more… Many more…
Continuous variableContinuous variable Interval variableInterval variable Ordinal variableOrdinal variable
Categorical variableCategorical variable Binary variableBinary variable Discrete variableDiscrete variable Ordinal variableOrdinal variable
88
Information CollectionsInformation Collections
1.1. Historical DataHistorical Data Pro:Pro: Convenient; Save a lot of work Convenient; Save a lot of work Con:Con: Outdated; Different Objectives and Designs; Unknown Outdated; Different Objectives and Designs; Unknown
Detailed InformationDetailed Information
2.2. CensusCensus Pro:Pro: reliable, accurate and comprehensive (e.g. Population reliable, accurate and comprehensive (e.g. Population
census)census) Con:Con: Time consuming; requiring more resources; difficult to Time consuming; requiring more resources; difficult to
investigate all subjects in the populationinvestigate all subjects in the population
3.3. SamplingSampling Pro:Pro: Efficient; Less risky; exploratory; informative Efficient; Less risky; exploratory; informative Caveats: Selection bias; misinterpretation; design flawCaveats: Selection bias; misinterpretation; design flaw
99
StatisticsStatistics
Descriptive StatisticsDescriptive Statistics Methods to organize and summarize informationMethods to organize and summarize information Mean, median, max, min, frequency and Mean, median, max, min, frequency and
proportions, etc. that summarize sample proportions, etc. that summarize sample demographicsdemographics
Inferential StatisticsInferential Statistics Methods to draw conclusions about a population Methods to draw conclusions about a population
based on information obtained from a sample of based on information obtained from a sample of the populationthe population
1010
Population
Sample
Descriptive Statistics
Inferential Statistics
Sampling Plan
Conclusion
1111
Summary StatisticsSummary Statistics
Measures of CenterMeasures of Center MeanMean
Median: the middle Median: the middle value in its ordered list value in its ordered list
Mode: the most Mode: the most frequently occurring frequently occurring value value
Measures of variationMeasures of variation Range: the difference Range: the difference
between the largest and between the largest and smallest value in the smallest value in the data set, i.e., data set, i.e., Range=Max-Min.Range=Max-Min.
Standard deviation: Standard deviation: measure variation by measure variation by indicating how far, on indicating how far, on average, the average, the observations are from observations are from the mean. the mean.
n
xx
n
ii
1
2
2 2 1
1 1
( )( )
1 1
n
in ni
i ii i
xx x x
ns
n n
We will talk more about data
summary and distribution graphs in SPSS 204 Workshop.
1212
Exercise: Determine for the mean, median and Exercise: Determine for the mean, median and mode, which measure of center is most appropriate mode, which measure of center is most appropriate
in the following case studies?in the following case studies?
A student takes four exams in a biology A student takes four exams in a biology class. His grades are 88, 75, 95, and 100. class. His grades are 88, 75, 95, and 100.
The National Association of REALTORS The National Association of REALTORS publishes data on resale prices of U.S. publishes data on resale prices of U.S. homes. homes.
In the 2003 Boston Marathon, there were In the 2003 Boston Marathon, there were two categories of official finishers: male two categories of official finishers: male and female, of which there were 10,737 and female, of which there were 10,737 and 6,309, respectively.and 6,309, respectively.
1313
Statistical Testing Statistical Testing ProceduresProcedures
1.1. Clarify study Clarify study objectives. objectives.
2.2. Establish Establish hypotheses. hypotheses.
3.3. Determine the Determine the outcome variables, outcome variables, treatment groups, treatment groups, risk factors and risk factors and covariates. covariates.
4.4. Perform appropriate Perform appropriate statistical testing.statistical testing.
5.5. Interpret results. Interpret results.
1414
Statistical Testing Statistical Testing ProceduresProcedures
1.1. Null HypothesisNull Hypothesis
- Ho: Mean_Treatment=Mean_ControlHo: Mean_Treatment=Mean_Control
2.2. Alternative HypothesisAlternative Hypothesis
- Ha: Mean_Treatment Ha: Mean_Treatment ≠≠ Mean_Control (Two-sided Test) Mean_Control (Two-sided Test)- Ha: Mean_Treatment > Mean_Control (One-sided Test)Ha: Mean_Treatment > Mean_Control (One-sided Test)- Ha: Mean_Treatment < Mean_Control (One-sided Test)Ha: Mean_Treatment < Mean_Control (One-sided Test)
3.3. Calculate statisticsCalculate statistics
4.4. Make InferenceMake Inference
- If P-value > 0.05, then Ho holdsIf P-value > 0.05, then Ho holds- If P-value < 0.05, then Ha holdsIf P-value < 0.05, then Ha holds
1515
Continuous VariablesContinuous Variables
Two or multiple treatment Two or multiple treatment groupsgroups
1616
Two samples t-testTwo samples t-test
Compare the means of a normally Compare the means of a normally distributed interval dependent variable distributed interval dependent variable for two independent groups. for two independent groups.
1,2/0
21
2
21
21
210
||:
11:
::.
::
N
p
A
ttifHrejectruledecision
nns
yytstatistictest
Hhypotehsisalt
Hhypothesisnull
1717
Case Study: FEVCase Study: FEV1 1 ChangesChanges
A new compound, ABC-A new compound, ABC-123, is being developed 123, is being developed for long-term treatment for long-term treatment of patients with chronic of patients with chronic asthma. Asthma patients asthma. Asthma patients were enrolled in a were enrolled in a double-blind study and double-blind study and randomized to receive randomized to receive daily oral or a placebo daily oral or a placebo
for 6 weeks.for 6 weeks.
FEV1 after 6-week treatment
Placebo Test
asthmatic patients
1818
FEVFEV1 1 DataData
Test GroupTest Group
Patient IDPatient ID BaselineBaseline week 6week 6
101101 1.351.35 n/an/a
103103 3.223.22 3.553.55
106106 2.782.78 3.153.15
108108 2.452.45 2.32.3
109109 1.841.84 2.372.37
110110 2.812.81 3.23.2
113113 1.91.9 2.652.65
116116 33 3.963.96
118118 2.252.25 2.972.97
120120 2.862.86 2.282.28
121121 1.561.56 2.672.67
124124 2.662.66 3.763.76
Placebo GroupPlacebo Group
Patient IDPatient ID BaselineBaseline week 6week 6
102102 3.013.01 3.93.9
104104 2.242.24 3.013.01
105105 2.252.25 2.472.47
107107 1.651.65 1.991.99
1111 1.951.95 n/an/a
112112 3.053.05 3.263.26
114114 2.52.5 2.552.55
115115 1.61.6 2.22.2
117117 .77.77 2.562.56
119119 2.062.06 2.92.9
122122 1.711.71 n/an/a
123123 3.543.54 2.922.92
1919
P-value P-value
What is the difference
between std and std error?
2020
Mean and Error BarMean and Error Bar
Conclusion:Conclusion:
As compared to As compared to placebo, the new placebo, the new drug did not show drug did not show any effect on FEVany effect on FEV11. .
2121
Paired t-testPaired t-test
Compare the means Compare the means of a normally of a normally distributed interval distributed interval dependent variable dependent variable for two related for two related groups.groups.
Test GroupTest Group
Patient IDPatient ID BaselineBaseline week 6week 6
101101 1.351.35 n/an/a
103103 3.223.22 3.553.55
106106 2.782.78 3.153.15
108108 2.452.45 2.32.3
109109 1.841.84 2.372.37
110110 2.812.81 3.23.2
113113 1.91.9 2.652.65
116116 33 3.963.96
118118 2.252.25 2.972.97
120120 2.862.86 2.282.28
121121 1.561.56 2.672.67
124124 2.662.66 3.763.76
2222
P-value
Conclusion: For subjects on the new drug,
FEV1 at week 6 is significantly higher than
baseline.
2323
One-way ANOVAOne-way ANOVA
Test for differences of the means for Test for differences of the means for continuous variables in multiple continuous variables in multiple independent treatment groups.independent treatment groups.
)(:
:
::.
...::
10
0
210
kkN
A
k
FFifHrejectruledecision
MSE
MSGFstatistictest
HnotHhypotehsisalt
Hhypothesisnull
2424
Case Study: HAM-A Scores in Case Study: HAM-A Scores in GADGAD
HAM-A Score after 10-week treatment
Placebo 100 mg SN-X95
Patients with GAD
25mg SN-X95
A new serotonin-update inhibiting A new serotonin-update inhibiting agent, SN-X95, is being studied in agent, SN-X95, is being studied in subjects with general anxiety subjects with general anxiety disorder (GAD). Fifty-two subjects disorder (GAD). Fifty-two subjects diagnosed with GAD were enrolled diagnosed with GAD were enrolled and randomly assigned to one of and randomly assigned to one of three treatment groups: three three treatment groups: three treatment groups: 25mg SN-X95, treatment groups: 25mg SN-X95, 100mg SN-X95 or placebo. After 10 100mg SN-X95 or placebo. After 10 weeks of once-daily oral dosing in a weeks of once-daily oral dosing in a double-blind fashion, a test based on double-blind fashion, a test based on the Hamilton Rating Scale for the Hamilton Rating Scale for Anxiety (HAM-A) was administered. Anxiety (HAM-A) was administered. This test consists of 14 anxiety-This test consists of 14 anxiety-related items (e.g. ‘anxious mood’, related items (e.g. ‘anxious mood’, ‘tension’, ‘insomnia’, ‘fear’, etc.), ‘tension’, ‘insomnia’, ‘fear’, etc.), each rated by the subject as ‘no each rated by the subject as ‘no present’, ‘mild’, ‘moderate’, ‘severe’, present’, ‘mild’, ‘moderate’, ‘severe’, or ‘very severe’. HAM-A test scores or ‘very severe’. HAM-A test scores were founded by summing the coded were founded by summing the coded values of all 14 items using the values of all 14 items using the numeric coding scheme of 0 for “not numeric coding scheme of 0 for “not present”, 1 for …. Are there any present”, 1 for …. Are there any differences in means HAM-A test differences in means HAM-A test score among the three groups?score among the three groups?
2525
DataDataLo-DoseLo-Dose Hi-DoseHi-Dose PlaceboPlacebo
2121 1616 2222
1818 2121 2626
1919 3131 2929
9999 2525 1919
2828 2323 9999
2222 2525 3333
3030 1818 3737
2727 2020 2525
2828 1818 2828
1919 1616 2626
2323 2424 9999
2222 2222 3131
2020 2121 2727
1919 1616 3030
2626 3333 2525
3535 2121 2222
9999 1717 3636
2626
P-value
2727
Mean and Error BarMean and Error Bar
Conclusion:Conclusion:
There is significant There is significant difference in mean difference in mean HAM-A among HAM-A among three treatment at three treatment at 95% confidence 95% confidence level. level.
2828
Categorical Variables Categorical Variables
Two or multiple treatment Two or multiple treatment groupsgroups
2929
Fisher’s Exact TestFisher’s Exact Test
A conservative non-parametric test A conservative non-parametric test about a relationship between two about a relationship between two categorical variables. categorical variables.
RespondersResponders Non-respondersNon-responders TotalTotal
Group 1Group 1 NN1111 NN1212 NN1111+N+N1212
Group 2Group 2 NN2211 NN2222 NN2211+N+N2222
CombinedCombined NN1111+N+N2211 NN1212+ N+ N2222 N N
3030
Case Study: CHF Incidence Case Study: CHF Incidence in CABG after ARAin CABG after ARA
A new adenosine-releasing agent (ARA), A new adenosine-releasing agent (ARA), thought to reduce side effects in patients thought to reduce side effects in patients undergoing coronary artery bypass surgery undergoing coronary artery bypass surgery (CABG), was studied in a pilot trial. (CABG), was studied in a pilot trial.
CHFCHF No CHFNo CHF TotalTotal
ARAARA 2 (6%)2 (6%) 3333 3535
PlaceboPlacebo 5 (25%)5 (25%) 2020 2525
CombinedCombined 77 5353 6060
Fisher’s exact test: p=0.0455
3131
Chi-square testChi-square test
Test a relationship between two Test a relationship between two categorical variables. The chi-square categorical variables. The chi-square test assumes that the expected test assumes that the expected value for each cell is five or higher. value for each cell is five or higher.
21
20
22
21
210
:
:
::.
::
ifHrejectruledecision
DEN
NUMstatistictest
ppHhypotehsisalt
ppHhypothesisnull
A
3232
Case Study: ADR Frequency Case Study: ADR Frequency with Antibiotic Treatmentwith Antibiotic Treatment
A study was conducted to monitor A study was conducted to monitor the incidence of GI adverse drug the incidence of GI adverse drug reactions of a new antibiotic used in reactions of a new antibiotic used in lower respiratory tract infections. lower respiratory tract infections.
RespondersResponders Non-respondersNon-responders TotalTotal
Test Test (new antibiotic)(new antibiotic) 22 (33%)22 (33%) 4444 6666
ControlControl(erythromycin)(erythromycin) 28 (54%)28 (54%) 2424 5353
CombinedCombined 50 (42%)50 (42%) 6868 118118
Chi-square test: p=0.0252; Fisher’s exact test: p=0.0385
3333
Other testsOther tests
One-way repeated One-way repeated measures ANOVAmeasures ANOVA
Repeated measures Repeated measures logistic regressionlogistic regression
Factorial ANOVAFactorial ANOVA Friedman testFriedman test Factorial logistic Factorial logistic
regressionregression Simple Linear Simple Linear
RegressionRegression Multiple RegressionMultiple Regression
Factor analysisFactor analysis Multiple logistic Multiple logistic
regressionregression Discriminant analysis Discriminant analysis One-way MANOVAOne-way MANOVA Multivariate multiple Multivariate multiple
regressionregression Canonical correlationCanonical correlation Analysis of covarianceAnalysis of covariance
We will cover all tests including non-parametric tests in SPSS 202 Workshop.
3434
Questions?Questions?
3535
Introduction to SPSSIntroduction to SPSS
3636
What is SPSS?What is SPSS?
Statistical software. Statistical software. 16 server licenses. 16 server licenses. SPSS 18. SPSS 18.
3737
SPSS Data EntrySPSS Data Entry
SPSS data can be entered manually. SPSS data can be entered manually. The format is ready for analysis.The format is ready for analysis.
SAS, Excel, txt, etc. data can be SAS, Excel, txt, etc. data can be easily imported to SPSS. easily imported to SPSS.
SPSS data files are saved as “SPSS SPSS data files are saved as “SPSS data document (.sav)”. data document (.sav)”.
SPSS output files are saved as “SPSS SPSS output files are saved as “SPSS viewer document (.spv)”. viewer document (.spv)”.
3838
SPSS Data EntrySPSS Data Entry
SPSS has a few unique features in data entry. SPSS has a few unique features in data entry. Categorical variables need to be coded. For instance, Categorical variables need to be coded. For instance,
code male as 1 and female as 0 or vice versa.code male as 1 and female as 0 or vice versa. When you have two treatments, test and control, please When you have two treatments, test and control, please
use 1 for test and 0 for control. use 1 for test and 0 for control. Categorical variables that are not coded in other Categorical variables that are not coded in other
sourced data files will not be imported or analyzed sourced data files will not be imported or analyzed
properly in SPSS. properly in SPSS. Continuous variables don’t need coding. Continuous variables don’t need coding. Missing values needs to be defined in “variable view” Missing values needs to be defined in “variable view”
page. page.
3939
Example: CDC Survey DataExample: CDC Survey Data
An allergy survey was conducted in An allergy survey was conducted in 2005 and 2006 to children more than 2005 and 2006 to children more than 1 year old. 1 year old.
Two data sets, allergy questionnaire Two data sets, allergy questionnaire and demographic information, are and demographic information, are saved in sas export format. saved in sas export format.
4040
TasksTasks
Import these two SAS data files to Import these two SAS data files to SPSS and save them as SPSS data SPSS and save them as SPSS data file. file.
Sort each data set by study ID.Sort each data set by study ID. Merge allergy variables and Merge allergy variables and
demographic variables.demographic variables. Save new data set as SPSS data file. Save new data set as SPSS data file.
4141
Log in SPSS Log in SPSS
CMH offers server CMH offers server version SPSS 18. Any version SPSS 18. Any employee can log in employee can log in SPSS from your SPSS from your employee account.employee account.
Go to Go to Start Start
->Program->Program
->Accessories->Accessories
-> Remote -> Remote Desktop Desktop ConnectionConnection
4242
Log in SPSS Log in SPSS
In the prompted In the prompted connection connection window, enter window, enter cmhterm. cmhterm.
ClickClick Connect. Connect.
4343
Log in SPSS Log in SPSS
In the Log On In the Log On Window, enter your Window, enter your cmh user namecmh user name and and passwordpassword. .
Choose log on to Choose log on to CMHCMH
ClickClick OK. OK.
4444
Task 1: Import Data Task 1: Import Data
We need to import two data sets to SPSS.We need to import two data sets to SPSS. Allergy qustionaire: Allergy qustionaire: aqq_d.xptaqq_d.xpt (xpt is sas export (xpt is sas export
file)file) Demographic information: Demographic information: demo_d.xptdemo_d.xpt
Please note that SPSS is on server and data Please note that SPSS is on server and data must be saved in shared drive such as must be saved in shared drive such as u u drive or w drivedrive or w drive. You will not be able to find . You will not be able to find the file in SPSS if you save them on your local the file in SPSS if you save them on your local disk.disk.
4545
Task 1: Import Data Task 1: Import Data
Double click spss Double click spss 18 icon on the 18 icon on the screen. screen.
In the task wizard, In the task wizard, click click Open an Open an existing sourceexisting source..
Click Click OKOK..
4646
Task 1: Import Data Task 1: Import Data
Just in case wizard Just in case wizard does not prompt, does not prompt, you can go to you can go to filefile
-> -> OpenOpen
-> -> DataData
4747
Task 1: Import Data Task 1: Import Data
Select Select the folderthe folder. . Choose Choose agg_d fileagg_d file.. Select Select xpt formatxpt format.. Click Click OpenOpen..
Note: SPSS is Note: SPSS is compatible with other compatible with other commonly used commonly used statistical and data statistical and data management software management software packages. Excel, SAS, packages. Excel, SAS, Access files are all Access files are all convertible to SPSS. convertible to SPSS.
4848
Task 1: Import Data Task 1: Import Data
Now the data is Now the data is open. open.
You can see the You can see the data in “data in “data Viewdata View” ” tab.tab.
4949
Task 1: Import Data Task 1: Import Data
The data structure, The data structure, variable name, variable name, label, etc. are in label, etc. are in ““Variable ViewVariable View” ” tab. tab.
5050
Task 2: Sort Data Task 2: Sort Data
Variable to be sort: Variable to be sort: SEQNSEQN, that is, , that is, Respondent sequence number. Respondent sequence number.
5151
Task 2: Sort Data Task 2: Sort Data
Go to Go to DataData and select and select Sort CasesSort Cases..
On On Sort Cases pageSort Cases page, , select the variable, select the variable, Respondent sequence Respondent sequence numbernumber..
Click on Click on right arrowright arrow.. Choose Choose AscendingAscending or or
DescendingDescending.. Click Click OKOK. .
5252
PracticePractice
Now let’s repeat this process by Now let’s repeat this process by doing the following:doing the following: Open the demographic data, Open the demographic data,
demo_d.xptdemo_d.xpt.. Sort the data by variable, Sort the data by variable, Respondent Respondent
Sequence NumberSequence Number. .
5353
Task 3: Merge Two Data Task 3: Merge Two Data SetsSets
Two data sets need to be linked by Two data sets need to be linked by key variables.key variables.
In our case, the key variable is In our case, the key variable is SEQN-SEQN-Respondent Sequence NumberRespondent Sequence Number..
Make sure the key variable has the Make sure the key variable has the same name and variable type in two same name and variable type in two data sets. data sets.
Both data sets needs to be sorted by Both data sets needs to be sorted by the key variable. the key variable.
5454
Task 3: Merge Two Data Task 3: Merge Two Data SetsSets
Under any data Under any data set, go to set, go to DataData
-> -> Merge FileMerge File
-> -> Add VariablesAdd Variables
5555
Task 3: Merge Two Data Task 3: Merge Two Data SetsSets
Choose the other Choose the other data to add on. data to add on.
Note, this page will Note, this page will look different in look different in SPSS 18. By all SPSS 18. By all means, choose the means, choose the other data set. other data set.
5656
Task 4: Save the New DataTask 4: Save the New Data
Go to Go to FileFile
-> -> Save As…Save As… Select Select the folderthe folder.. Create new file, Create new file,
MergedDataMergedData.. Choose Choose SPSS data SPSS data
formatformat. . Click Click SaveSave..
5757
Task 4: Save the New DataTask 4: Save the New Data
Go to Go to DataData
-> -> Merge FileMerge File
-> -> Add VariablesAdd Variables
5858
Questions?Questions?
We will cover more We will cover more data management in data management in SPSS 203 workshop. SPSS 203 workshop.
5959
Let’s play with SPSSLet’s play with SPSS
6060
Project 1: FEVProject 1: FEV1 1 ChangesChanges
6161
Case Study: FEVCase Study: FEV1 1 ChangesChanges
A new compound, ABC-A new compound, ABC-123, is being developed 123, is being developed for long-term treatment for long-term treatment of patients with chronic of patients with chronic asthma. Asthma patients asthma. Asthma patients were enrolled in a were enrolled in a double-blind study and double-blind study and randomized to receive randomized to receive daily oral or a placebo daily oral or a placebo
for 6 weeks.for 6 weeks.
FEV1 after 6-week treatment
Placebo Test
asthmatic patients
6262
FEVFEV1 1 DataData
Test GroupTest Group
Patient IDPatient ID BaselineBaseline week 6week 6
101101 1.351.35 n/an/a
103103 3.223.22 3.553.55
106106 2.782.78 3.153.15
108108 2.452.45 2.32.3
109109 1.841.84 2.372.37
110110 2.812.81 3.23.2
113113 1.91.9 2.652.65
116116 33 3.963.96
118118 2.252.25 2.972.97
120120 2.862.86 2.282.28
121121 1.561.56 2.672.67
124124 2.662.66 3.763.76
Placebo GroupPlacebo Group
Patient IDPatient ID BaselineBaseline week 6week 6
102102 3.013.01 3.93.9
104104 2.242.24 3.013.01
105105 2.252.25 2.472.47
107107 1.651.65 1.991.99
1111 1.951.95 n/an/a
112112 3.053.05 3.263.26
114114 2.52.5 2.552.55
115115 1.61.6 2.22.2
117117 .77.77 2.562.56
119119 2.062.06 2.92.9
122122 1.711.71 n/an/a
123123 3.543.54 2.922.92
6363
TasksTasks
1.1. Log in to intranet and open SPSS.Log in to intranet and open SPSS.
2.2. Define variables and missing values in “variable Define variables and missing values in “variable
view” tab. view” tab.
3.3. Enter data in “data view” tab. Enter data in “data view” tab.
4.4. Perform two-sample t-tests to compare FEV1 at Perform two-sample t-tests to compare FEV1 at
6 weeks between test and control. 6 weeks between test and control.
5.5. Generate mean and error bar graph for two Generate mean and error bar graph for two
groups. groups.
6.6. Interpret the SPSS output and make conclusion.Interpret the SPSS output and make conclusion.
6464
Tasks to be continuedTasks to be continued
7.7. Perform paired t-test to compare the FEV Perform paired t-test to compare the FEV between baseline and 6 weeks for test between baseline and 6 weeks for test group. group.
8.8. Interpret SPSS results and draw conclusions.Interpret SPSS results and draw conclusions.
9.9. Save SPSS data and SPSS output Save SPSS data and SPSS output respectively. respectively.
10.10. Open SPSS data and SPSS output by double Open SPSS data and SPSS output by double clicking the icons. clicking the icons.
11.11. Close both files. Close both files.
6565
Project 2: Project 2: HAM-A Scores in HAM-A Scores in GADGAD
6666
Case Study: HAM-A Scores in Case Study: HAM-A Scores in GADGAD
HAM-A Score after 10-week treatment
Placebo 100 mg SN-X95
Patients with GAD
25mg SN-X95
A new serotonin-update inhibiting A new serotonin-update inhibiting agent, SN-X95, is being studied in agent, SN-X95, is being studied in subjects with general anxiety subjects with general anxiety disorder (GAD). Fifty-two subjects disorder (GAD). Fifty-two subjects diagnosed with GAD were enrolled diagnosed with GAD were enrolled and randomly assigned to one of and randomly assigned to one of three treatment groups: three three treatment groups: three treatment groups: 25mg SN-X95, treatment groups: 25mg SN-X95, 100mg SN-X95 or placebo. After 10 100mg SN-X95 or placebo. After 10 weeks of once-daily oral dosing in a weeks of once-daily oral dosing in a double-blind fashion, a test based on double-blind fashion, a test based on the Hamilton Rating Scale for the Hamilton Rating Scale for Anxiety (HAM-A) was administered. Anxiety (HAM-A) was administered. This test consists of 14 anxiety-This test consists of 14 anxiety-related items (e.g. ‘anxious mood’, related items (e.g. ‘anxious mood’, ‘tension’, ‘insomnia’, ‘fear’, etc.), ‘tension’, ‘insomnia’, ‘fear’, etc.), each rated by the subject as ‘no each rated by the subject as ‘no present’, ‘mild’, ‘moderate’, ‘severe’, present’, ‘mild’, ‘moderate’, ‘severe’, or ‘very severe’. HAM-A test scores or ‘very severe’. HAM-A test scores were founded by summing the coded were founded by summing the coded values of all 14 items using the values of all 14 items using the numeric coding scheme of 0 for “not numeric coding scheme of 0 for “not present”, 1 for …. Are there any present”, 1 for …. Are there any differenceds in means HAM-A test differenceds in means HAM-A test score among the three groups?score among the three groups?
6767
DataDataLo-DoseLo-Dose Hi-DoseHi-Dose PlaceboPlacebo
2121 1616 2222
1818 2121 2626
1919 3131 2929
9999 2525 1919
2828 2323 9999
2222 2525 3333
3030 1818 3737
2727 2020 2525
2828 1818 2828
1919 1616 2626
2323 2424 9999
2222 2222 3131
2020 2121 2727
1919 1616 3030
2626 3333 2525
3535 2121 2222
9999 1717 3636
6868
TasksTasks
1.1. Open data in excel. Make sure the data structure, Open data in excel. Make sure the data structure,
variables and missing values are set up properly. variables and missing values are set up properly.
2.2. Import Excel to SPSS.Import Excel to SPSS.
3.3. Perform one-way ANOVA to compare high dose, low dose Perform one-way ANOVA to compare high dose, low dose
and control groups.and control groups.
4.4. Generate mean and error bar graph for three groups.Generate mean and error bar graph for three groups.
5.5. If the global F-test is significant, then perform post-hoc If the global F-test is significant, then perform post-hoc
pair-wise comparisons. pair-wise comparisons.
6.6. Interpret the SPSS output and make conclusion.Interpret the SPSS output and make conclusion. 7.7. Save data and output. Save data and output.
8.8. Close files. Close files.
6969
Project 3: CHF Incidence in Project 3: CHF Incidence in CABG after ARACABG after ARA
7070
Case study: CHF Incidence in Case study: CHF Incidence in CABG after ARACABG after ARA
A new adenosine-releasing agent (ARA), thought A new adenosine-releasing agent (ARA), thought to reduce side effects in patients undergoing to reduce side effects in patients undergoing coronary artery bypass surgery (CABG), was coronary artery bypass surgery (CABG), was studied in a pilot trial That enrolled 35 patients studied in a pilot trial That enrolled 35 patients who receive active medication and 20 patients who receive active medication and 20 patients who received a placebo. Follow-up observation who received a placebo. Follow-up observation revealed that 2 patients who received active revealed that 2 patients who received active medication and 5 patients who received the medication and 5 patients who received the placebo had shown symptoms of congestive heart placebo had shown symptoms of congestive heart failure (CHF) within 90 days post surgery. Is this failure (CHF) within 90 days post surgery. Is this evidence of a reduced rate of CHF for patients evidence of a reduced rate of CHF for patients treated with the ARA compound?treated with the ARA compound?
7171
TasksTasks
1.1. Open SPSS data. Open SPSS data.
2.2. Summarize frequency, percentage in two-way Summarize frequency, percentage in two-way
contingency table.contingency table.
3.3. Perform Fisher’s exact test. Perform Fisher’s exact test.
4.4. Perform Chi-square test.Perform Chi-square test.
5.5. Compare Fisher’s exact test with Chi-square Compare Fisher’s exact test with Chi-square
test. test.
6.6. Interpret the SPSS output and make conclusion.Interpret the SPSS output and make conclusion. 7.7. Close files. Close files.
7272
Project 4: ADR Frequency Project 4: ADR Frequency with Antibiotic Treatmentwith Antibiotic Treatment
7373
Case Study: ADR Frequency Case Study: ADR Frequency with Antibiotic Treatmentwith Antibiotic Treatment
A study was conducted to monitor the A study was conducted to monitor the incidence of GI adverse drug reactions incidence of GI adverse drug reactions of a new antibiotic used in lower of a new antibiotic used in lower respiratory tract infections. Two parallel respiratory tract infections. Two parallel groups were included in the study. One groups were included in the study. One group consisted of 66 LRTI patients group consisted of 66 LRTI patients randomized to receive the new randomized to receive the new treatment and a reference group of 52 treatment and a reference group of 52 patients randomized to receive patients randomized to receive erythromycin. erythromycin.
7474
TasksTasks
1.1. Open SPSS data. Open SPSS data.
2.2. Summarize frequency, percentage in two-way Summarize frequency, percentage in two-way
contingency table.contingency table.
3.3. Perform Fisher’s exact test. Perform Fisher’s exact test.
4.4. Perform Chi-square test.Perform Chi-square test.
5.5. Compare Fisher’s exact test with Chi-square Compare Fisher’s exact test with Chi-square
test. test.
6.6. Interpret the SPSS output and make conclusion.Interpret the SPSS output and make conclusion. 7.7. Close files. Close files.
7575
Questions?Questions?
Let us know statistics Let us know statistics topics you are topics you are interested. interested.
7676
In summary…In summary…
7777
Thank YouThank You
For more information, visit my websiteFor more information, visit my website
http://www.childrensmercy.org/contenthttp://www.childrensmercy.org/content/view.aspx?id=9740/view.aspx?id=9740
Or go to Scope ->Research -> Medical Or go to Scope ->Research -> Medical Research -> StatisticsResearch -> Statistics
7878
ReferencesReferences
Medical Statistics by Campbell et al.Medical Statistics by Campbell et al. Introductory Statistics by Neil WeissIntroductory Statistics by Neil Weiss Common Statistical Methods for Common Statistical Methods for
Clinical Research by WalkerClinical Research by Walker