Am sorry I did not frame my question well. After doing more studies and research I think what am trying to ask is creating a predictor of chronological age from a log.regression, and this will be the biological age. Is that right? ... View more

The graph represent a two-piecewise linear regression model. This is the link to the article https://pubmed.ncbi.nlm.nih.gov/32411758/ ... View more

Sorry about the confusion my question is specific to the sql, case-when procedure not the put statement. This is a synthesis data. data test; input patient; datalines; -999 12 11 10 -9 -7 -5 9 8 7 6 5 4 3 1 ; run; The data is numeric and I converted into character using this code: data test2; set test; pt_discharge=put(patient,4.); run; Now I will like to rename the observations from -999 to 1 to character values. This is the outcome (table) I hope to achieve.   patient  pt_discharge -999  missing2 12  homeH 11   hospice 10  otherD -9 missing -7  unknown -5 invalid 9   otherH 8   dead 7   court 6   long 5   short 4   LAMA 3  admit 1 home   ... View more

Problem still persist ... View more

So I'm still working on this question. I created a sample data for better understanding. So this purpose is to identify age values in different 'agegroups' categories. For example, 0 is present in both years, months and days and I will like to have that in one group '< 15 yrs'   data test; input patient_id patient_age patient_age_unit pt_age_code $; datalines;   1231 24 2 months 1232 30 1 years 1233 3 1 years 1234 33 1 years 1235 0 0 newborn 1236 4 1 years 1237 0 1 years 1238 11 1 years 1239 90 1 years 1230 1 0 newborn 1212 0 2 months 1213 6 1 years 1214 11 2 months 1215 12 1 years 1216 0 3 days 1217 1 1 years 1218 34 1 years 1219 30 3 days 1220 1 2 months 1221 94 1 years ; run;   I created this new codes but am not sure what else am doing wrong. Please help data pt_age_grp (compress=yes keep= patient_id patient_age patient_age_unit pt_age_code agegroup ); set test;   if pt_age_recode = "newborn" then do;     agegroup = '<15yrs'; end;     else if patient_age <=30 and pt_age_recode = "days" then do;     agegroup = '<15yrs'; end;     else if patient_age <=11 and pt_age_recode = "months" then do;     agegroup = '<15yrs'; end;     else if 1 <= patient_age <=15 and pt_age_recode = "years" then do;     agegroup = '<15yrs'; end;     else if 16 <= patient_age <= 34 and pt_age_recode = "years" then do;     agegroup = '16-34yrs'; end;     else if 35 <= patient_age <= 54 and pt_age_recode = "years" then do;     agegroup = '35-54yrs'; end;     else if patient_age >= 55 and pt_age_recode = "years" then do;     agegroup = '55+yrs'; end;     else do;     agegroup = 'Others'; end; run; ... View more

@Tom Please ignore the initial output table. I made a mistake. Using the data above, I trried the following code it seems to work but I need a second opnion to see if it work on a large dataset; data test2; set test; where fent=1; if fent=1 then do; if sum(oxy,hydro,codeine)=0 then F_drug=1; else if sum(oxy,hydro,codeine)>0 then F_drug =2; end; run; proc freq data=test2; table F_drug; run; ... View more

@Reeza @PhilC  The numbers in the output are made up. I tried usgin this code but my output is not what I wanted. My desired output is when fent is 1 and other drugs are 0, and  when fent is 1 and other drugs is 1. data test2; set test; where fent=1; if fent=1 then do; if oxy=0 or hydro=0 or codeine =0 then single=1; else if oxy=1 or hydro=1 or codeine =1 then single =2; end; run; ... View more