Check your data more efficiently

Paper number: TT02
CHECK YOUR DATA MORE EFFICIENTLY
Jian Hua (Daniel) Huang, Forest Laboratories Inc, NJ ABSTRACT:
%CHKDATA is a SAS macro program designed to check the data in an efficient and user-friendly way. First, the macro can check the data structure by generating three types of key information: the contents of dataset, its associated SAS format, and a collection of all variable names listed horizontally. Second, the macro can generate the distinct values and frequency counts for any specified variables. Third, the macro can define any potential data issues and generate the reports. In addition, %CHKDATA has one important special feature. The macro can work on multiple datasets at the same time. When processing multiple datasets, it combines data information from each input dataset and list them side-by-side in one report, therefore, people can easily review and even compare the information among all input datasets. This is especially helpful for people working on data integration or anything where multiple datasets are used and compared. In summary, %CHKDATA is a very useful tool for anyone who wants to review and understand data quickly BACKGROUND:
Whether the task is to create a report or to derive a new dataset, people start from some source data and, more importantly, they need to understand the source data correctly and comprehensively. Normally, people review the source data by simply opening the dataset and reading it directly. However, if the data is huge, which includes dozens of variables and thousands of records, and if there is not only one single dataset but multiple datasets are involved, and if these datasets are not from one study but from many different studies, reading all the data one-by-one could be slow and unreliable. It is better to have utility programs that help us review and understand the data more efficiently. %CHKDATA is a SAS macro program designed to check the data in a more efficient and user-friendly way. The macro is originally called '%GETSTART' (sounds like 'get start'). Because, at the beginning, it was designed only to check the data structure and generate distinct values, so people could use such information and get works (i.e. table programming) started quickly. Later, more functions were added to the macro. In addition to collecting information on data structures, the macro also checks for the potential data issues and reports them properly and timely. The macro also becomes more powerful by its ability to process multiple datasets at the same time. Due to its increased functional scope, the macro was renamed to %CHKDATA (sounds like 'check data'). %CHKDATA MACRO:
The %CHKDATA macro has two major functions. First, the macro can check the data structures for input dataset and generate distinct values for any specified variables. Second, the macro can define and summarize potential data issues, and report them properly. In addition, %CHKDATA has one special feature in which the macro can process multiple datasets at the same time. USING %CHKDATA TO CHECK THE DATA STRUCTURE AND GENERATE DISTINCT VALUES:
As mentioned before, %CHKDATA can generate three types of key information for data structures: the contents of dataset, the SAS format values, and a collection of all variable names which are listed horizontally on one page. Let us review these functions with below examples. Example 1; display the contents of input dataset. %chkdata(lib=xxxx21d, data=addm, content=yes, report=addm_content1); Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-29 at time: 14:53
List of the contents of each input dataset side-by-side

Variable Attrib XXXX21D
Variable Attrib XXXX21D
Names -utes ADDM Names -utes ADDM
----------------------------------------------- -----------------------------------------------
AGE Type 1 Format DATE
Length 8
Label Age DOBN Type 1
Format Length 8
Label Date of Birth (numeric)
CENTRE Type 2 Format
Length 3
Label Centre Number INVNO Type 2
Format $ Length 4
Label Investigator ID
COUNTRY Type 2 Format $
Length 14
Label Country ITT Type 2
Format Length 7
Label ITT
COUNTRYC Type 2 Format $YNS
The contents of dataset: ADDM from one single study: XXXX21D is generated by calling %CHKDATA and the sample output is listed above. The output lists variable names and the values of four key attributes: 'type', 'length', 'label' and 'format'. To save page space, if there is only one input dataset, each page contains two panels. If there are multiple input datasets, then the contents of each dataset will be listed side- by-side. We will discuss later about how %CHKDATA deal with multiple datasets. Example 2; display the SAS formats of input study. %chkdata(lib=xxxx21d, printfmt=yes, report=xxxx21d_format1); Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-26 at time: 15:21
List of SAS format of each input study side-by-side
______________________________________ ______________________________________
xxxx21d xxxx21d
Format _____________________________ Format _____________________________
Names Start End Label Names Start End Label
-------------------------------------- --------------------------------------
ACCEPTS 1 1 YES, ENTERELY 6 6 NEW TREATMENT
ACCEPTABLE GIVEN
2 2 YES, SOMEWHAT 7 7 OTHERS
ACCEPTABLE 8 8 STOPPED
3 3 UNCERTAIN (TEMPORAL)
4 4 NO, SOMEWHAT 9 9 STOPPED
UNACCEPTABLE (DEFINITIVE)
5 5 NO, ENTERELY 10 10 DOSAGE REDUCED
UNACCEPTABLE 11 11 INTERRUPTED
98 98 N.D. 12 12 DISCONTINUED
99 99 N.A. (PERMANENTLY)
13 13 DOSAGE INCREASED
ACTIO1S 1 1 None 14 14 DOSE NOT CHANGED
2 2 Dosage reduced 15 15 DOSE REDUCED
3 3 Interrupted 16 16 DRUG WITHDRAWN
4 4 Discontinued 17 17 DOSE INCREASED
(permanently) 18 18 DRUG WITHDRAWN
5 5 Dosage Increased PERMANENTLY
6 6 Dose not changed 98 98 N.D.
7 7 Dose reduced 99 99 N.A.
8 8 Drug withdrawn
9 9 Dose increased ACTIV1S 0 0 Screen
98 98 N.D. 1 1 Change Subject
99 99 N.A. Status
The SAS format of one single study: XXXX21D is generated. The output includes format name, its start and end values, and most importantly, the label. To save page space, if there is only one input study, each page Example 3, list of all variable names on one page horizontally. %chkdata(lib=issd, data=d_prof2, allvar=yes, report=prof2_allvar); Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-26 at time: 15:21
Check data from: ISSD.D_PROF2
List all variable names horizotally, so they are convenient to be reviewed or edited
Obs var1 var2 var3 var4 var5 var6 var7 var8 var9 var10 var11 var12 var13 var14 var15
1 AGE AGEGRP AGEGRP_C BIRTHDT BIRTHDTC BMI BMIGRP BMIGRP_C CENTER COMPLETE COMPLE_C COPDSEV COPDSE_C COPDSE_O COUNTRY
Obs var16 var17 var18 var19 var20 var21 var22 var23 var24 var25 var26 var27 var28 var29 var30
1 DEATH DEATHDT DEATHDTC DEATH_C DESIGN DOSE DOSE_C DUR_STDY DUR_TRT FDSDT FDSDT99 FDSDT99C FDSDTC HEIGHTCM HEIGHTIN
Obs var31 var32 var33 var34 var35 var36 var37 var38 var39 var40 var41 var42 var43 var44 var45 var46 var47
1 INITIALS INVNO ITT ITT_C LASTDT LASTDTC LDSDT LDSDT99 LDSDT99C LDSDTC PATYRS PERIOD PERIOD_C PID PP PP_C RACE
Obs var48 var49 var50 var51 var52 var53 var54 var55 var56 var57 var58 var59 var60 var61 var62 var63
1 RACEOTH RACETYPE RACETY_C RACE_C RACE_O RAND RAND_C SAFETY SAFETY_C SCREENO SCRNDT SCRNDTC SEX SEX_C SMOKER SMOKER_C
Obs var64 var65 var66 var67 var68 var69 var70 var71 var72 var73 var74 var75
1 SMOKER_O STUDYID TERMSPEC TREASON TREASO_C TREASO_O TREATC TREATGP TREATGPC TREATSQ WEIGHTKG WEIGHTLB
There are totally 75 variables (var1-var75) existed in input dataset: D_PROF2. All variable names are collected and listed on one page horizontally, therefore, it is easy to review the variable names and copy and In addition to displaying data structure, %CHKDATA can also check the distinct values and their frequency counts for any specified variables. The following two examples demonstrate how %CHKDATA generates the distinct values for any specified variables from the input datasets. Example 4; display the distinct values of any specified variables (the output %chkdata(lib=xxxx22d, data=medicati, report=cmed1_chkdata1, Check data from:xxxx22D.MEDICATI
List unique values and frequency count of: STARTYYY
List First 30 Observation Only
Obs STARTYYY COUNT
1 04 1
2 1974 1
3 1976 1
4 1978 1
5 1980 2
6 1982 1
7 1984 5
8 1985 2
9 1986 2
10 NA 4
11 UK 15
The distinct values and their frequency counts of variable: STARTYYY are generated and listed as above. Some strange values of STARTYYY, such as: '04', 'NA', 'UK', have been detected by %CHKDATA. The information is very useful as it reminds people to pay attention to those strange values when working on the dataset. Btw, if multiple variables are listed under the macro option 'UNIVAR=', the macro will generate distinct values and frequency counts for each input variable and list them on separated pages. Again, it is also able to apply this function on multiple datasets at the same time. We will discuss this special feature Example 5; display the distinct values of any specified variables (the output %chkdata(lib=xxxxpk09d, data=advs, report=vital2_chkdata1, univar=timing, idvar=visitno visitid period); Check data from: XXXXPK09D.ADVS
List unique values and frequency count of: TIMING, sorted by ID variables: VISITNO VISITID PERIOD
Obs VISITNO VISITID PERIOD TIMING COUNT
1 -2.00 SCREENING 999 -99.00 198
2 -1.00 TREATMENT PERIOD 1 DAY -1 999 -99.00 63
3 1.00 TREATMENT PERIOD 1 DAY 1 1 0.00 63
4 1.00 TREATMENT PERIOD 1 DAY 1 1 0.08 63
5 1.00 TREATMENT PERIOD 1 DAY 1 1 0.50 63
6 1.00 TREATMENT PERIOD 1 DAY 1 1 2.00 63
7 1.00 TREATMENT PERIOD 1 DAY 1 1 6.00 63
8 1.00 TREATMENT PERIOD 1 DAY 1 1 12.00 63
9 2.00 TREATMENT PERIOD 1 DAY 2 1 24.00 63
10 3.00 TREATMENT PERIOD 1 DAY 3 1 0.00 63
11 3.00 TREATMENT PERIOD 1 DAY 3 1 0.08 63
12 3.00 TREATMENT PERIOD 1 DAY 3 1 0.50 63
13 3.00 TREATMENT PERIOD 1 DAY 3 1 2.00 63
14 3.00 TREATMENT PERIOD 1 DAY 3 1 6.00 63
15 3.00 TREATMENT PERIOD 1 DAY 3 1 12.00 63
16 4.00 TREATMENT PERIOD 1 DAY 4 1 24.00 63
17 5.00 TREATMENT PERIOD 1 DAY 5 1 48.00 63
18 6.00 TREATMENT PERIOD 2 DAY -1 1 -99.00 57
19 7.00 TREATMENT PERIOD 2 DAY 1 2 0.00 57
20 7.00 TREATMENT PERIOD 2 DAY 1 2 0.08 57
21 7.00 TREATMENT PERIOD 2 DAY 1 2 0.50 57
22 7.00 TREATMENT PERIOD 2 DAY 1 2 2.00 57
23 7.00 TREATMENT PERIOD 2 DAY 1 2 6.00 57
24 7.00 TREATMENT PERIOD 2 DAY 1 2 12.00 57
25 8.00 TREATMENT PERIOD 2 DAY 2 2 -99.00 12
26 8.00 TREATMENT PERIOD 2 DAY 2 2 24.00 57
27 9.00 TREATMENT PERIOD 2 DAY 3 2 0.00 57
28 9.00 TREATMENT PERIOD 2 DAY 3 2 0.08 57
29 9.00 TREATMENT PERIOD 2 DAY 3 2 0.50 57
30 9.00 TREATMENT PERIOD 2 DAY 3 2 2.00 57
31 9.00 TREATMENT PERIOD 2 DAY 3 2 6.00 57
32 9.00 TREATMENT PERIOD 2 DAY 3 2 12.00 57
33 10.00 TREATMENT PERIOD 2 DAY 4 2 24.00 57
34 11.00 TREATMENT PERIOD 2 DAY 5 2 48.00 57
In this case, the variable TIMING is first sorted by three ID variables: VISITNO, VISITID, and PERIOD. Then its distinct values and frequency counts, within sorted variables, are generated and listed as above. USING %CHKDATA TO DEFINE AND REPORT POTENTIAL DATA ISSUES:
We just discussed in detail how %CHKDATA can check the data structures and data values. In the next paragraph, we will discuss how %CHKDATA can check for any potential data issues. We use the following Example 6, check data and report potential data issue. %chkdata (lib=xxxx22d, data=medicati, report=cmed1_issue1, listobs=15, idvar=MEDIC_TR dose dose1, fmtvar=MEDIC_TR, issue=%str(which variable to use as the correct CMED dosage: dose or Report data issue: which variable to use as the correct CMED dosage: dose or dose1?
Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-26 at time: 15:22
Check data from: XXXX22D.MEDICATI
List first 30 observation only
Obs MEDIC_TR DOSE dose1
1 ENAP 10.00000 200
2 BECLAZONE 250.00000 200
3 FLIXOTIDE 250.00000 100
4 MONOPRIL 10.00000 100
5 VERAPAMIL 80.00000 100
6 ZINNAT 500.00000 100
7 FLIXOTIDE 250.00000.
8 PRESTARIUM 4.00000.
9 OMEZ 20.00000 50
10 BECLAZONE 250.00000 50
11 URSOSAN 500.00000 18
12 ENALAPRIL 10.00000 25
13 BECOTIDE 300.00000 25
14 VERAPAMIL 80.00000 400
15 CAPOTEN 12.50000 400
In this case, two variables: DOSE, DOSE1 are found from the same input dataset: MEDICATI. These two variables have the similar name and label, it is hard to tell which one represents the real dosage of concomitant medication (MEDIC_TR). The potential data issue is defined as: 'which variable to use as the correct CMED dosage: dose or dose1?'. The macro defines this potential data issue in the where statement: 'where= (dose1 ^=dose)' and then generates corresponding output as above. This report is saved as a permanent list file by the macro option 'report=cmed1_issue1'. Later, the report can be sent to the corresponding group, i.e. data management group, for further review or data cleaning. In addition, by assigning macro option 'fmtvar=MEDIC_TR', it removes its associated format of variable 'MEDIC_TR', so the value of MEDIC_TR can be printed and fit on one page. SPECIAL FEATURE, %CHKDATA CHECKS MULTIPLE DATASETS AT THE SAME TIME:
%CHKDATA has one special feature; it can deal with multiple input datasets, from different studies, at the same time. Below are examples of this important feature. Example 7; display the contents of multiple datasets from different studies. %chkdata(lib=xxxx22d xxxx30d xxxx31d, data=adcm medicati, content=yes, Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-26 at time: 15:21
List of the contents of each input dataset side-by-side
Variable Attrib XXXX22D XXXX30D XXXX31D
Names -utes MEDICATI ADCM ADCM
-----------------------------------------------------------------------------------------------------
ATC_TEXT Type 2 2 2
Length 200 200 200
Label ATC Text ATC Text ATC Text
Format $ $ $
BATCHNO Type 1
Length 8
Label Batch number
Format
CAS Type 2 2
Length 10 10
Label CAS number CAS number
Format $ $
The contents of two datasets: ADDM and MEDICATI, from three different studies: XXXX22D XXXX30D XXXX31D, are generated and listed on one page, side-by-side. The output allows people to review and compare the contents of all input datasets in an easy and quick way. This special feature is very helpful for people who work on the data integration or anything dealing with multiple datasets at the same time. It is worth to mention here that every input dataset, i.e. ADDM and MEDICATI, is not necessary to be existed in each input study. %CHKDATA can automatically detect which dataset exists, and then list the contents for those datasets that exist. For example, in this case, MEDICATI exists only in XXXX22D, and ADCM exists in the other two studies: XXXX30D, XXXX31D. Example 8; display SAS format for multiple studies (list 3 studies per page). %chkdata (lib=xxxx21d xxxx24d xxxx25d xxxxpk09d xxxx30d xxxx31d, printfmt=yes, ncolpage=3, report=prof2_format2); Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-26 at time: 15:21
List of SAS format of each input study side-by-side
________________________________________________________________________________________________________________________________
xxxx21d xxxx24d xxxx25d
Format _______________________________________ _______________________________________ _______________________________________
Names Start End Label Start End Label Start End Label
--------------------------------------------------------------------------------------------------------------------------------
ACCEPTS 1 1 YES, ENTERELY ACCEPTABLE 1 1 YES, ENTERELY ACCEPTABLE 1 1 YES, ENTERELY ACCEPTABLE
2 2 YES, SOMEWHAT ACCEPTABLE 2 2 YES, SOMEWHAT ACCEPTABLE 2 2 YES, SOMEWHAT ACCEPTABLE
3 3 UNCERTAIN 3 3 UNCERTAIN 3 3 UNCERTAIN
4 4 NO, SOMEWHAT UNACCEPTABLE 4 4 NO, SOMEWHAT UNACCEPTABLE 4 4 NO, SOMEWHAT UNACCEPTABLE
5 5 NO, ENTERELY UNACCEPTABLE 5 5 NO, ENTERELY UNACCEPTABLE 5 5 NO, ENTERELY UNACCEPTABLE
98 98 N.D. 98 98 N.D. 98 98 N.D.
99 99 N.A. 99 99 N.A. 99 99 N.A.
ACTIO1S 1 1 None 1 1 None 1 1 None
2 2 Dosage reduced 2 2 Dosage reduced 2 2 Dosage reduced
3 3 Interrupted 3 3 Interrupted 3 3 Interrupted
4 4 Discontinued (permanently) 4 4 Discontinued (permanently) 4 4 Discontinued (permanently)
5 5 Dosage Increased 5 5 Dosage Increased 5 5 Dosage Increased
6 6 Dose not changed 6 6 Dose not changed 6 6 Dose not changed
7 7 Dose reduced 7 7 Dose reduced 7 7 Dose reduced
8 8 Drug withdrawn 8 8 Drug withdrawn 8 8 Drug withdrawn
9 9 Dose increased 9 9 Dose increased 9 9 Dose increased
98 98 N.D. 98 98 N.D. 98 98 N.D.
99 99 N.A. 99 99 N.A. 99 99 N.A.
Reported by SAS user: JHHUANG, through SAS program: TEST_CHKDATA.SAS, on date: 2008-09-26 at time: 15:21
List of SAS format of each input study side-by-side
________________________________________________________________________________________________________________________________
xxxxpk09d xxxx30d xxxx31
Format _______________________________________ _______________________________________ _______________________________________
Names Start End Label Start End Label Start End Label
--------------------------------------------------------------------------------------------------------------------------------
ACCEPTS 1 1 YES, ENTIRELY ACCEPTABLE 1 1 YES, ENTERELY ACCEPTABLE 1 1 YES, ENTERELY ACCEPTABLE
2 2 YES, SOMEWHAT ACCEPTABLE 2 2 YES, SOMEWHAT ACCEPTABLE 2 2 YES, SOMEWHAT ACCEPTABLE
3 3 UNCERTAIN 3 3 UNCERTAIN 3 3 UNCERTAIN
4 4 NO, SOMEWHAT UNACCEPTABLE 4 4 NO, SOMEWHAT UNACCEPTABLE 4 4 NO, SOMEWHAT UNACCEPTABLE
5 5 NO, ENTIRELY UNACCEPTABLE 5 5 NO, ENTERELY UNACCEPTABLE 5 5 NO, ENTERELY UNACCEPTABLE
98 98 N.D. 98 98 N.D. 98 98 N.D.
99 99 N.A. 99 99 N.A. 99 99 N.A.
%CHKDATA generates SAS formats for six studies at one time and lists them side-by-side. The macro option of 'ncolpage=3' (stands for 'number of columns listed per page') requests that each page lists SAS SUMMARY:
In summary, %CHKDATA is a very useful tool to check data efficiently. It can check both the data structures and distinct data values; therefore, people can get start quickly on their work. In addition, the macro can also define potential data issues detected from input datasets, and report these issues properly to the data management team. It helps staff to continually keep the data clean and correct. Finally, the macro can check multiple datasets, even from different studies, at the same time, and summarize the information in one report. This special feature is especially helpful for people who work on data integration or anything dealing with multiple datasets at the same time. %CHKDATA has its limitation as well. Once the macro defines a potential data issue, it generates the report and saves it into a separated file. It will be better if the macro can automatically concatenate all correlated data issues together, and save them into one big final report. CONCLUSION:
%CHKDATA macro is simple and practical. It will be a very useful tool for people who want to review and CONTACT INFORMATION:
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