The Cochran-Mantel-Haenszel test statistic is one of the many statistical measures used in case control studies. To obtain this useful statistic, which compares the odds ratio, you can declare the CMH option on the TABLE statement in PROC FREQ.
General Syntax
PROC FREQ DATA = ;
TABLE X*Y/CMH;
RUN;
Example:
The data set Migraine contains hypothetical data for a clinical trial of migraine treatment. Subjects of both genders receive either a new drug therapy or a placebo. Their response to treatment is coded as ‘Better’ or ‘Same’. The data are recorded as cell counts, and the number of subjects for each treatment and response combination is recorded in the variable Count.
data Migraine;
input Gender $ Treatment $ Response $ Count @@;
datalines;
female Active Better 16 female Active Same 11
female Placebo Better 5 female Placebo Same 20
male Active Better 12 male Active Same 16
male Placebo Better 7 male Placebo Same 19
;
Run;
The following PROC FREQ statements create a multiway table stratified by Gender, where Treatment forms the rows and Response forms the columns. The CMH option produces the Cochran-Mantel-Haenszel statistics. For this stratified table, estimates of the common relative risk and the Breslow-Day test for homogeneity of the odds ratios are also displayed. The NOPRINT option suppresses the display of the contingency tables.
proc freq data=Migraine;
tables Gender*Treatment*Response / cmh;
weight Count;
title ‘Clinical Trial for Treatment of Migraine Headaches’;
run;
For a stratified table, the three CMH statistics displayed in Output above test the same hypothesis. The significant -value (0.004) indicates that the association between treatment and response remains strong after adjusting for gender.
The CMH option also produces a table of relative risks, as shown in next Output. Because this is a prospective study, the relative risk estimate assesses the effectiveness of the new drug; the “Cohort (Col1 Risk)” values are the appropriate estimates for the first column (the risk of improvement). The probability of migraine improvement with the new drug is just over two times the probability of improvement with the placebo.
The large -value for the Breslow-Day test (0.2218) in Output 3.7.3 indicates no significant gender difference in the odds ratios.
EPOCH RESEARCH INSTITUTE OFFER:
General Syntax
PROC FREQ DATA = ;
TABLE X*Y/CMH;
RUN;
Example:
The data set Migraine contains hypothetical data for a clinical trial of migraine treatment. Subjects of both genders receive either a new drug therapy or a placebo. Their response to treatment is coded as ‘Better’ or ‘Same’. The data are recorded as cell counts, and the number of subjects for each treatment and response combination is recorded in the variable Count.
data Migraine;
input Gender $ Treatment $ Response $ Count @@;
datalines;
female Active Better 16 female Active Same 11
female Placebo Better 5 female Placebo Same 20
male Active Better 12 male Active Same 16
male Placebo Better 7 male Placebo Same 19
;
Run;
The following PROC FREQ statements create a multiway table stratified by Gender, where Treatment forms the rows and Response forms the columns. The CMH option produces the Cochran-Mantel-Haenszel statistics. For this stratified table, estimates of the common relative risk and the Breslow-Day test for homogeneity of the odds ratios are also displayed. The NOPRINT option suppresses the display of the contingency tables.
proc freq data=Migraine;
tables Gender*Treatment*Response / cmh;
weight Count;
title ‘Clinical Trial for Treatment of Migraine Headaches’;
run;
For a stratified table, the three CMH statistics displayed in Output above test the same hypothesis. The significant -value (0.004) indicates that the association between treatment and response remains strong after adjusting for gender.
The CMH option also produces a table of relative risks, as shown in next Output. Because this is a prospective study, the relative risk estimate assesses the effectiveness of the new drug; the “Cohort (Col1 Risk)” values are the appropriate estimates for the first column (the risk of improvement). The probability of migraine improvement with the new drug is just over two times the probability of improvement with the placebo.
The large -value for the Breslow-Day test (0.2218) in Output 3.7.3 indicates no significant gender difference in the odds ratios.
EPOCH RESEARCH INSTITUTE OFFER:
SAS TRAINING | SAS CERTIFICATION | SAS CLASSROOM TRAINING | SAS LIVE WEB TRAINING | SAS TRAINING FOR CORPORATE
Email us: info@epoch.co.in Call :079 – 40327000
SAS Training & Placement Programs with Internship : Epoch Research Institute India Largest and Oldest SAS Training Institute
Epoch Research Institute Links:
Labels:
CHM, Proc Freq, Procedure, SAS, Statistics,
#Base SAS training, #BIGDATASASTRAININGEPOCH, #Clinical SAS Online Training, #epochresearchinstitute SAS TRAINING, #Live SAS web Training, #online SAS training, #SAS Live web classroom Training, #SAS Online Training, %display, %goto, %window, Add-Ins, Advance, Advance interview, Advance SAS, allanalytics, analysis, analytics, analytics courses online, analytics training courses, application, BANGLORE, base, Base SAS, BASE SAS CERTIFICATION, Base SAS training, Beginner, BI, Big Data, big data analytics training bangalore, bigdata, bioavalibility, books, Business Intelligence, Career, Certified SAS Programmer, CHM, clinical, clinical data namagement, clinical SAS, Clinical SAS Online Training, clinical trial, Clinical Trial Questions, code, code free, Coding, Correlation, CRO, custom style, DASHBOARD, data, Data Exploration, Data Integration, DATA MANAGEMENT, DEBUG, defination, definition, drug discovery, EG, Electronic Submission, Eminor, enhance editor, Enterprise Guide, epoch feedback, epoch sas training, EPOCH SAS TRAINING AHMEDABAD, ERROR, ETL, excel, Explore, FDA, Forecasting, FREE, Free SAS, Free Training, FREE WEBINAR, freq report, GCHART, hadoop, ICH GCP quiz, IMPORT, Index, Interview Questions, JOB, know, Library, Life Science, Live SAS web Training, locf, LOG, macro, Macro interview questions, marketing, News, OLAP, online SAS training, Options, Performance Tuning, pharma, phase trial, Pivot table, Predictive analytics, Predictive Modeling, Proc Freq, Proc means, Proc Mixed, proc sql, PROC TRANSPOSE, Procedure, Programmer, programming, quiz, REG, Regulatory Authority, reporting, sample program, SAS, SAS 9.3, SAS Advance, SAS BI, SAS BI Certification, SAS BI Dashboard 4.3 – What’s New, sas book, SAS Consultant, SAS Dataset, SAS DI Certification, SAS EG 5.1, SAS Eminor, sas enterprise guide, sas functions, SAS Good programming Practice, SAS Graph, SAS Instructor Tips, SAS Interview Preparation, SAS Links, SAS Live web classroom Training, SAS Macro, SAS Online Training, SAS Programming Tips, sas publication, SAS Reporting, SAS Stored Process, SAS Style, SAS TIPS, SAS Training, SAS WBCAST, SAS Webinar, sastalks, sastraining, SHORTCUT, SQL, SQL. DATA STEPS, Standards, STAT, Statistics, Strategy, summarizing, Technology, terminology, TIPS, Trafic lighting, training, training., TRANSPOSE, trial, TTEST, user interface, utility, variable, Web Report Studio, Webinar, Whats New, Whats new in SAS 9.3, http://www.epoch.co.in