How can I convert to long format using data steps? This is the data
Data on seizure counts for 59 epileptics.
Source: Table 2 (page 664) in Thall and Vail (1990).
With permission of Blackwell Publishing.
Reference: Thall, P.F. and Vail, S.C. (1990). Some covariance models for
longitudinal count data with overdispersion. Biometrics, 46, 657-671,
Description:
The data are from a placebo-controlled clinical trial of 59 epileptics.
Patients with partial seizures were enrolled in a randomized
clinical trial of the anti-epileptic drug, progabide. Participants
in the study were randomized to either progabide or a placebo, as
an adjuvant to the standard anti-epileptic chemotherapy. Progabide
is an anti-epileptic drug whose primary mechanism of action is to
enhance gamma-aminobutyric acid (GABA) content; GABA is the
primary inhibitory neurotransmitter in the brain.
Prior to receiving treatment, baseline data on the number of
epileptic seizures during the preceding 8-week interval were
recorded. Counts of epileptic seizures during 2-week intervals
before each of four successive post-randomization clinic visits
were recorded.
Variable List:
Patient ID, Treatment (0=Placebo, 1=Progabide), Age,
Baseline 8 week seizure count, First 2 week seizure count,
Second 2 week seizure count, Third 2 week seizure count,
Fourth 2 week seizure count.
1 0 31 11 5 3 3 3
2 0 30 11 3 5 3 3
3 0 25 6 2 4 0 5
4 0 36 8 4 4 1 4
5 0 22 66 7 18 9 21
6 0 29 27 5 2 8 7
7 0 31 12 6 4 0 2
8 0 36 52 40 20 23 12
9 0 37 23 5 6 6 5
10 0 28 10 14 13 6 0
11 0 36 52 26 12 6 22
12 0 24 33 12 6 8 5
13 0 28 18 4 4 6 2
14 0 36 42 7 9 12 14
15 0 26 87 16 24 10 9
16 0 26 50 11 0 0 5
17 0 28 18 0 0 3 3
18 0 31 111 37 29 28 29
19 0 32 18 3 5 2 5
20 0 21 20 3 0 6 7
21 0 29 12 3 4 3 4
22 0 21 9 3 4 3 4
23 0 32 17 2 3 3 5
24 0 25 28 8 12 2 8
25 0 30 55 18 24 76 25
26 0 40 9 2 1 2 1
27 0 19 10 3 1 4 2
28 0 22 47 13 15 13 12
29 1 18 76 11 14 9 8
30 1 32 38 8 7 9 4
31 1 20 19 0 4 3 0
32 1 20 10 3 6 1 3
33 1 18 19 2 6 7 4
34 1 24 24 4 3 1 3
35 1 30 31 22 17 19 16
36 1 35 14 5 4 7 4
37 1 57 11 2 4 0 4
38 1 20 67 3 7 7 7
39 1 22 41 4 18 2 5
40 1 28 7 2 1 1 0
41 1 23 22 0 2 4 0
42 1 40 13 5 4 0 3
43 1 43 46 11 14 25 15
44 1 21 36 10 5 3 8
45 1 35 38 19 7 6 7
46 1 25 7 1 1 2 4
47 1 26 36 6 10 8 8
48 1 25 11 2 1 0 0
49 1 22 151 102 65 72 63
50 1 32 22 4 3 2 4
51 1 25 42 8 6 5 7
52 1 35 32 1 3 1 5
53 1 21 56 18 11 28 13
54 1 41 24 6 3 4 0
55 1 32 16 3 5 4 3
56 1 26 22 1 23 19 8
57 1 21 25 2 3 0 1
58 1 36 13 0 0 0 0
59 1 37 12 1 4 3 2
My code Data epilepsy1;
Set sasdata.epilepsy;
Seizure count = TSC1;
Drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy2;
Set epilepsy;
Seizure count = TSC2;
drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy3;
Set epilepsy;
Seizure count = TSC3;
drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy4;
Set epilepsy;
Seizure count = TSC4;
drop TSC1 TSC2 TSC3 TSC4;
run;
Data sasuser.epilepsylong;
Set epilepsy1 epilepsy2 epilepsy3 epilepsy4;
run;
No doubt someone can respond and give a direct answer to your question, inferring what you mean.
But I suggest this is a good opportunity to develop the habit of not only showing the data you have, but also showing what you want the data to look like. It certainly helps your correspondents and possibly helps you to resolve ambiguities in stating your objective.
Even better, if you could show your starting data in the form of a sas data step, you would be assisting us in helping youi.
Your code will likely error out, at this line in particular:
My codeData epilepsy1;
Set sasdata.epilepsy;
Seizure count = TSC1;
Drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy2;
Set epilepsy;
Seizure count = TSC2;
drop TSC1 TSC2 TSC3 TSC4;
run;
I'm going to assume that you're trying to restructure your data from wide too long. To do this, there are several options:
How can I convert to long format using data steps? This is the data
Data on seizure counts for 59 epileptics.
Source: Table 2 (page 664) in Thall and Vail (1990).
With permission of Blackwell Publishing.
Reference: Thall, P.F. and Vail, S.C. (1990). Some covariance models for
longitudinal count data with overdispersion. Biometrics, 46, 657-671,
Description:
The data are from a placebo-controlled clinical trial of 59 epileptics.
Patients with partial seizures were enrolled in a randomized
clinical trial of the anti-epileptic drug, progabide. Participants
in the study were randomized to either progabide or a placebo, as
an adjuvant to the standard anti-epileptic chemotherapy. Progabide
is an anti-epileptic drug whose primary mechanism of action is to
enhance gamma-aminobutyric acid (GABA) content; GABA is the
primary inhibitory neurotransmitter in the brain.
Prior to receiving treatment, baseline data on the number of
epileptic seizures during the preceding 8-week interval were
recorded. Counts of epileptic seizures during 2-week intervals
before each of four successive post-randomization clinic visits
were recorded.
Variable List:
Patient ID, Treatment (0=Placebo, 1=Progabide), Age,
Baseline 8 week seizure count, First 2 week seizure count,
Second 2 week seizure count, Third 2 week seizure count,
Fourth 2 week seizure count.
1 0 31 11 5 3 3 3
2 0 30 11 3 5 3 3
3 0 25 6 2 4 0 5
4 0 36 8 4 4 1 4
5 0 22 66 7 18 9 21
6 0 29 27 5 2 8 7
7 0 31 12 6 4 0 2
8 0 36 52 40 20 23 12
9 0 37 23 5 6 6 5
10 0 28 10 14 13 6 0
11 0 36 52 26 12 6 22
12 0 24 33 12 6 8 5
13 0 28 18 4 4 6 2
14 0 36 42 7 9 12 14
15 0 26 87 16 24 10 9
16 0 26 50 11 0 0 5
17 0 28 18 0 0 3 3
18 0 31 111 37 29 28 29
19 0 32 18 3 5 2 5
20 0 21 20 3 0 6 7
21 0 29 12 3 4 3 4
22 0 21 9 3 4 3 4
23 0 32 17 2 3 3 5
24 0 25 28 8 12 2 8
25 0 30 55 18 24 76 25
26 0 40 9 2 1 2 1
27 0 19 10 3 1 4 2
28 0 22 47 13 15 13 12
29 1 18 76 11 14 9 8
30 1 32 38 8 7 9 4
31 1 20 19 0 4 3 0
32 1 20 10 3 6 1 3
33 1 18 19 2 6 7 4
34 1 24 24 4 3 1 3
35 1 30 31 22 17 19 16
36 1 35 14 5 4 7 4
37 1 57 11 2 4 0 4
38 1 20 67 3 7 7 7
39 1 22 41 4 18 2 5
40 1 28 7 2 1 1 0
41 1 23 22 0 2 4 0
42 1 40 13 5 4 0 3
43 1 43 46 11 14 25 15
44 1 21 36 10 5 3 8
45 1 35 38 19 7 6 7
46 1 25 7 1 1 2 4
47 1 26 36 6 10 8 8
48 1 25 11 2 1 0 0
49 1 22 151 102 65 72 63
50 1 32 22 4 3 2 4
51 1 25 42 8 6 5 7
52 1 35 32 1 3 1 5
53 1 21 56 18 11 28 13
54 1 41 24 6 3 4 0
55 1 32 16 3 5 4 3
56 1 26 22 1 23 19 8
57 1 21 25 2 3 0 1
58 1 36 13 0 0 0 0
59 1 37 12 1 4 3 2
My code Data epilepsy1;
Set sasdata.epilepsy;
Seizure count = TSC1;
Drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy2;
Set epilepsy;
Seizure count = TSC2;
drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy3;
Set epilepsy;
Seizure count = TSC3;
drop TSC1 TSC2 TSC3 TSC4;
run;
Data epilepsy4;
Set epilepsy;
Seizure count = TSC4;
drop TSC1 TSC2 TSC3 TSC4;
run;
Data sasuser.epilepsylong;
Set epilepsy1 epilepsy2 epilepsy3 epilepsy4;
run;
You are describing a data transposition. Use proc transpose for that:
proc transpose data=sasdata.epilepsy out=sasuser.epilepsylong
name=interval prefix=count;
by patient_id treatment age baseline;
var TSC1 TSC2 TSC3 TSC4;
run;
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