Hi All,   I am running a multiple logistic regression analysis with mortality (event = 1) as the dependent variable and various ranges of age (65-69, 70-74, 75-79, 80+) as the independent variables (see code below). When running the analysis, the variable "Age 80+" is displaying zero degrees of freedom and there is no subsequent result generated (see image below)   The code is as follows: "proc logistic data=WORK.OBESITY; class Age_65_69 Age_70_74 Age_75_79 Age_80_ / param=glm descending; model Overall_Mortality(event='1')=Age_65_69 Age_70_74 Age_75_79 Age_80_ / link=logit technique=fisher; run;"     Reviewing the data, each independent variable has either 0 or 1 as possible inputs, and none of the columns share the same sum.   I would greatly appreciate any possible explanation and subsequent solution for this problem!   Thanks! ... View more

Hi All,   I am running a logistic regression model with mortality as the dependent variable (event of interest is "1", which equals mortality) and 3 treatments as the independent variable ("0" signifies the patient did not receive therapy, whereas "1" signifies the patient did receive therapy).   When running the model, SAS defaults to reporting the event of "0 vs 1" in the odds ratio plots (see below).   Code:  proc logistic data=WORK.TOCI plots=(oddsratio(cldisplay=serifarrow) ); class Received_Hydroxychloroquine Received_Azithromycin Treatment / param=glm; model Mortality(event='1')=Received_Hydroxychloroquine Received_Azithromycin Treatment / link=logit technique=fisher; run;   I would like to model this analysis based on "1 vs. 0", in other words the predictability of mortality if the patient received therapy. I adjusted the code by adding DESC, and the order seems to have reversed, but the odds ratio plot is still reporting "0 vs. 1" and the point estimates have not changed.   Code:  proc logistic descending data=WORK.TOCI plots=(oddsratio(cldisplay=serifarrow) ); class Received_Hydroxychloroquine Received_Azithromycin Treatment / param=glm; model Mortality(event='1')=Received_Hydroxychloroquine Received_Azithromycin Treatment / link=logit technique=fisher; run;   Is there any additional issue in the code of the program that is causing this to happen, or am I misinterpreting the results?   Thanks in advance, Matt ... View more