Reading ids unexposed to any pollutants

[ak2011]

Hello,

I would appreciate if someone could help me with the SAS code to count the number of subjects) not exposed to any of the the 4 agents (a1, a2,a3 and a4 ) below. Exposed is 1 and unexposed is zero (0).         From the dataset, ids os3, os6, os7 and os9 are unexposed to any of the agents so the freq should be 4. I don't  know if my approach is ok. In the results, I have controlling for a1=0 and a2=0. Does anyone has a better approach to this please? My code and log are found below; results are attached.

Thank you.

ak.

data agents_exp;
input id$ a1 a2 a3 a4;
datalines;
os1 1 0 0 1
os2 1 1 0 0
os3 0 0 0 0 
os5 1 0 0 1 
os6 0 0 0 0
os7 0 0 0 0
os8 1 0 1 1
os9 0 0 0 0
;
run;
proc print;

data a;
set agents_exp;
if a1 ne 0 then delete;
else if a2 ne 0 then delete;
else if a3 ne 0 then delete;
else if a4 ne 0 then delete;
run;


proc freq data=a;
tables a1*a2*a3*a4;
run; 

OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;

72

73 data agents_exp;

74 input id$ a1 a2 a3 a4;

75 datalines;

NOTE: The data set WORK.AGENTS_EXP has 8 observations and 5 variables.

NOTE: DATA statement used (Total process time):

real time 0.01 seconds

cpu time 0.01 seconds

84 ;

85 run;

86 proc print;

87

NOTE: There were 8 observations read from the data set WORK.AGENTS_EXP.

NOTE: PROCEDURE PRINT used (Total process time):

real time 0.19 seconds

cpu time 0.20 seconds

88 data a;

89 set agents_exp;

90 if a1 ne 0 then delete;

91 else if a2 ne 0 then delete;

92 else if a3 ne 0 then delete;

93 else if a4 ne 0 then delete;

94 run;

NOTE: There were 8 observations read from the data set WORK.AGENTS_EXP.

NOTE: The data set WORK.A has 4 observations and 5 variables.

NOTE: DATA statement used (Total process time):

real time 0.03 seconds

cpu time 0.03 seconds

95

96

97 proc freq data=a;

98 tables a1*a2*a3*a4;

99 run;

NOTE: There were 4 observations read from the data set WORK.A.

NOTE: PROCEDURE FREQ used (Total process time):

real time 0.17 seconds

cpu time 0.16 seconds

100

101 OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;

113

[novinosrin]

 data agents_exp;
input id$ a1 a2 a3 a4;
datalines;
os1 1 0 0 1
os2 1 1 0 0
os3 0 0 0 0 
os5 1 0 0 1 
os6 0 0 0 0
os7 0 0 0 0
os8 1 0 1 1
os9 0 0 0 0
;
run;
proc print;

proc sql;
select count(*)
from agents_exp
where max(a1,a2,a3,a4)=0;
quit;

[ballardw · Accepted solution]

---

@novinosrin wrote:

 data agents_exp;
input id$ a1 a2 a3 a4;
datalines;
os1 1 0 0 1
os2 1 1 0 0
os3 0 0 0 0 
os5 1 0 0 1 
os6 0 0 0 0
os7 0 0 0 0
os8 1 0 1 1
os9 0 0 0 0
;
run;
proc print;

proc sql;
select count(*)
from agents_exp
where max(a1,a2,a3,a4)=0;
quit;

---

@ak2011 did not show any missing results for the 4 values. If some missings were possible (unknown exposure perhaps) and you want known "not exposed" I would suggest including an N=4 in the condition.

[novinosrin]

Yes Sir @ballardw . Very good observation. I agree

[ballardw]

We can also filter data at use with where clause like:

proc print data=agents_exp;
   where max(a1,a2,a3,a4) =0;
run;

[ak2011]

Thanks very much! Is a very good method.