How to create counter variable with if condition - sas

So I am still a newbie in SAS and therefore any help is greatly appreciated.
I am trying to create 2 counter variables:
1st one - COUNTTREATMENTVISITS that counts +1 whenever FOLDERNAME variable in my dataset has any values except 'Visit 1 Screening 1','Visit 2 Screening 2','Visit 17 Safety FU'
2nd one - COUNTETPATIENT that counts +1 whenever DSTERM2 variable in my dataset has any values except 'Complete'
after getting these 2 counter variables straight I just want to calculate and display in output EEOT_RATE as per the formula :EEOT_RATE=COUNTETPATIENT/(COUNTTREATMENTVISITS/1000)
I already did some SAS code(using Cluepoints platform for clinical trials) but I can't get past the errors(see below code and error snapshot):
data RAND1 (keep= CP_PATIENT CP_REGION CP_CENTER RANDYN RANDYN_STD RANDOMIZED_AT
RANDOMIZED_AT_INT);
set data_in.rand;
where RANDYN='Yes';
by FOLDERNAME;
retain COUNTTREATMENTVISITS=0;
if FOLDERNAME NOT in('Visit 1 Screening 1','Visit 2 Screening 2','Visit 17 Safety FU') then
COUNTTREATMENTVISITS+1;
run;
proc sort data = RAND1;
by CP_PATIENT;
run;
data DS1 (keep = CP_PATIENT CP_REGION CP_CENTER ET DSTERM2 DSCONT FOLDERNAME);
set data_in.DS;
retain COUNTETPATIENT=0;
if strip(DSTERM2) NE 'Completed' then COUNTETPATIENT+1;
run;
proc sort data = DS1;
by CP_PATIENT;
run;
data data_out.output;
merge RAND1 (in=a) DS1 (in=b);
by CP_PATIENT;
if a;
if CP_PATIENT='' then delete;
EEOT_RATE=COUNTETPATIENT/(COUNTTREATMENTVISITS/1000);
run;
Error snapshot

SAS Syntax for retain statement is:
retain COUNTTREATMENTVISITS 0;
See documentation here : https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.5/lestmtsref/p0t2ac0tfzcgbjn112mu96hkgg9o.htm#p115mm1hsepln9n11cxtkk7wejim

Related

Produce custom table in SAS with a subsetted data set

I want to use SAS and eg. proc report to produce a custom table within my workflow.
Why: Prior, I used proc export (dbms=excel) and did some very basic stats by hand and copied pasted to an excel sheet to complete the report. Recently, I've started to use ODS excel to print all the relevant data to excel sheets but since ODS excel would always overwrite the whole excel workbook (and hence also the handcrafted stats) I now want to streamline the process.
The task itself is actually very straightforward. We have some information about IDs, age, and registration, so something like this:
data test;
input ID $ AGE CENTER $;
datalines;
111 23 A
. 27 B
311 40 C
131 18 A
. 64 A
;
run;
The goal is to produce a table report which should look like this structure-wise:
ID NO-ID Total
Count 3 2 5
Age (mean) 27 45.5 34.4
Count by Center:
A 2 1 3
B 0 1 1
A 1 0 1
It seems, proc report only takes variables as columns but not a subsetted data set (ID NE .; ID =''). Of course I could just produce three reports with three subsetted data sets and print them all separately but I hope there is a way to put this in one table.
Is proc report the right tool for this and if so how should I proceed? Or is it better to use proc tabulate or proc template or...?
I found a way to achieve an almost match to what I wanted. First if all, I had to introduce a new variable vID (valid ID, 0 not valid, 1 valid) in the data set, like so:
data test;
input ID $ AGE CENTER $;
if ID = '' then vID = 0;
else vID = 1;
datalines;
111 23 A
. 27 B
311 40 C
131 18 A
. 64 A
;
run;
After this I was able to use proc tabulate as suggested by #Reeza in the comments to build a table which pretty much resembles what I initially aimed for:
proc tabulate data = test;
class vID Center;
var age;
keylabel N = 'Count';
table N age*mean Center*N, vID ALL;
run;
Still, I wonder if there is a way without introducing the new variable at all and just use the SAS counters for missing and non-missing observations.
UPDATE:
#Reeza pointed out to use the proc format to assign a value to missing/non-missing ID data. In combination with the missing option (prints missing values) in proc tabulate this delivers the output without introducing a new variable:
proc format;
value $ id_fmt
' ' = 'No-ID'
other = 'ID'
;
run;
proc tabulate data = test missing;
format ID $id_fmt.;
class ID Center;
var age;
keylabel N = 'Count';
table N age*(mean median) Center*N, (ID=' ') ALL;
run;

SAS Retain statement - how to retain previous non missing values into new column for comparison

I am simply looking to create a new column retaining the value of a specific column within the previous record, so that I can compare the existing column against the new column. Further down the line I want to be able to output records whereby the values in both columns are different and lose the records where the values are the same
Essentially I want my dataset to look like this, where the first idr has the retained date set to null:
Idr Date1 Date2
1 20/01/2016 .
1 20/01/2016 20/01/2016
1 18/10/2016 20/01/2016
2 07/03/2016 .
2 18/05/2016 07/03/2016
2 21/10/2016 18/05/2016
3 29/01/2016 .
3 04/02/2016 29/01/2016
3 04/02/2016 04/02/2016
I have used code along the following lines in the past whereby I have created a temporary variable referencing the data I want to retain:
date_temp=date1;
data example2;
set example1;
by idr date1;
date_temp=date1;
retain date_temp ;
if first.idr then do;
date_temp=date1;
end;else do;
date2=date_temp;
end;
run;
I have searched the highs and lows of google - Any help would be greatly appreciated
The trick here is to set the value of the retained variable ready for the next row after you've already output the current row, rather than relying on the default implicit output at the end of the data step:
data example2;
set example1;
by idr;
retain date2;
if first.idr then call missing(date2);
output;
date2 = date1;
format date2 ddmmyy10.;
run;
Logic that executes after the output statement doesn't make any difference to the row that's just been output, but until the data step proceeds to the next iteration, everything is still in the PDV, including variables that are being retained across to the next row, so this is an opportunity to update them. More details on the PDV.
Another way of doing this, using the lag function:
data example3;
set example1;
date2 = lag(date1);
if idr ne lag(idr) then call missing(date2);
run;
Be careful when using lag - it returns the value from the last time that instance of the lag function was executed during your data step, not necessarily the value of that variable from the previous row, so weird things tend to happen if you do something like if condition then mylaggedvar=lag(var);
To achieve your final outcome (remove records where the idr and date are the same as the previous row), you can easily achieve this without creating the extra column. Providing the data is sorted by idr and date1, then just use first.date1 to keep the required records.
data have;
input Idr Date1 :ddmmyy10.;
format date1 ddmmyy10.;
datalines;
1 20/01/2016
1 20/01/2016
1 18/10/2016
2 07/03/2016
2 18/05/2016
2 21/10/2016
3 29/01/2016
3 04/02/2016
3 04/02/2016
;
run;
data want;
set have;
by idr date1;
if first.date1 then output;
run;

SAS Create missing numeric ids into individual observations.

I need to outline a series of ID numbers that are currently available based on a data set in which ID's are already assigned (if the ID is on the file then its in use...if its not on file, then its available for use).
The issue is I don't know how to create a data set that displays ID numbers which are between two ID #'s that are currently on file - Lets say I have the data set below -
data have;
input id;
datalines;
1
5
6
10
;
run;
What I need is for the new data set to be in the following structure of this data set -
data need;
input id;
datalines;
2
3
4
7
8
9
;
run;
I am not sure how I would produce the observations of ID #'s 2, 3 and 4 as these would be scenarios of "available ID's"...
My initial attempt was going to be subtracting the ID values from one observation to the next in order to find the difference, but I am stuck from there on how to use that value and add 1 to the observation before it...and it all became quite messy from there.
Any assistance would be appreciated.
As long as your set of possible IDs is know, this can be done by putting them all in a file and excluding the used ones.
e.g.
data id_set;
do id = 1 to 10;
output;
end;
run;
proc sql;
create table need as
select id
from id_set
where id not in (select id from have)
;
quit;
Create a temporary variable that stores the previous id, then just loop between that and the current id, outputting each iteration.
data have;
input id;
datalines;
1
5
6
10
;
run;
data need (rename=(newid=id));
set have;
retain _lastid; /* keep previous id value */
if _n_>1 then do newid=_lastid+1 to id-1; /* fill in numbers between previous and current ids */
output;
end;
_lastid=id;
keep newid;
run;
Building on Jetzler's answer: Another option is to use the MERGE statement. In this case:
note: before merge, sort both datasets by id (if not already sorted);
data want;
merge id_set (in=a)
have (in=b); /*specify datasets and vars to allow the conditional below*/
by id; /*merge key variable*/
if a and not b; /*on output keep only records in ID_SET that are not in HAVE*/
run;

SAS: in the DATA step, how to calculate the grand mean of a subset of observations, skipping over missing values

I'm trying to calculate the grand mean of a subset of observations (e.g., observation 20 to observation 50) in the data step. In this calculation, I also want to skip over (ignore) any missing values.
I've tried to play around with the mean function using various if … then statements, but I can't seem to fit all of it together.
Any help would be much appreciated.
For reference, here's the basic outline of my data steps:
data sas1;
infile '[file path]';
input v1 $ 1-9 v2 $ 11 v3 13-17 [redacted] RPQ 50-53 [redacted] v23 101-106;
v1=translate(v1,"0"," ");
format [redacted];
label [redacted];
run;
data gmean;
set sas1;
id=_N_;
if id = 10-40 then do;
avg = mean(RPQ);
end;
/*Here, I am trying to calculate the grand mean of the RPQ variable*/
/*but only observations 10 to 40, and skipping over missing values*/
run;
Use the automatic variable /_N_/ to id the rows. Use a sum value that is retained row to row and then divide by the number of observations at the end. Use the missing() function to determine the number of observations present and whether or not to add to the running total.
data stocks;
set sashelp.stocks;
retain sum_total n_count 0;
if 10<=_n_<=40 and not missing(open) then do;
n_count=n_count+1;
sum_total=sum_total+open;
end;
if _n_ = 40 then average=sum_total/n_count;
run;
proc print data=stocks(obs=40 firstobs=40);
var average;
run;
*check with proc means that the value is correct;
proc means data=sashelp.stocks (firstobs=10 obs=40) mean;
var open;
run;

Frequency of a value across multiple variables?

I have a data set of patient information where I want to count how many patients (observations) have a given diagnostic code. I have 9 possible variables where it can be, in diag1, diag2... diag9. The code is V271. I cannot figure out how to do this with the "WHERE" clause or proc freq.
Any help would be appreciated!!
Your basic strategy to this is to create a dataset that is not patient level, but one observation is one patient-diagnostic code (so up to 9 observations per patient). Something like this:
data want;
set have;
array diag[9];
do _i = 1 to dim(diag);
if not missing(diag[_i]) then do;
diagnosis_Code = diag[_i];
output;
end;
end;
keep diagnosis_code patient_id [other variables you might want];
run;
You could then run a proc freq on the resulting dataset. You could also change the criteria from not missing to if diag[_i] = 'V271' then do; to get only V271s in the data.
An alternate way to reshape the data that can match Joe's method is to use proc transpose like so.
proc transpose data=have out=want(keep=patient_id col1
rename=(col1=diag)
where=(diag is not missing));
by patient_id;
var diag1-diag9;
run;