Top 20 Clinical SAS Interview Questions and Answers in 2023

Clinical SAS Interview Questions and Answers

There are several opportunities in clinical SAS just waiting for you. Also known as SAS clinical, this field uses SAS technology to conduct clinical trial data analysis. It is generally used by biotech, pharmaceutical, and clinical research companies.

This article will look at some of the questions that you should expect in a clinical SAS interview. Remember, this is an important field that calls for highly qualified experts. The best way to land a job, therefore, is to be outstanding in your interview.

Take your time and go through the following:

1.    Kindly Describe the Phases of Clinical Trials

This is a common question in clinical SAS interviews which attempts to establish if you know a piece of given basic information about this field. Your answer should be brief and straight to the point. Convince the interviewer that you know what your job entails.

Sample Answer

There are four phases of clinical trials. In phase one, the new drug or treatment is tested on a small number of people, usually 20-80, to establish whether it is safe. In phase 2, the number of people is increased from 20-80 to 100-300 to see whether it is effective or not. The number is increased to between 1000 and 3000 people in phase 3 to establish its effectiveness, side effects, and whether it is better than commonly used treatments. Phase 4 is a study phase that includes post-marketing and establishing the risks the drug poses.

2.      Do You Understand the Validation Procedure? Walk Us Through How You Would Validate in TLG and For Analysis Data Set?

This is a technical question on something that you encounter in your job. The interviewer is trying to establish your competence and expertise. The best approach to such a question is to give a step-to-step response and convincing the interviewer that you are good at your job.

Sample Answer

The validation procedure is usually used to check the output of the SAS program, which a source programmer generally generates. The validator will therefore write the program and generate the output. A good program has a similar output to that of the SAS programmer output. For TLG, it is usually done through a manual check on the output, whereas for the analysis data set, one must use PROC COMPARE.

3.      Can One Use PROC COMPARE to Validate Listings?

This is a follow-up question. These usually are asked based on your previous response. It would be best to convince the interviewer that you understand the concept discussed in your previous response. This will also reveal your level of expertise.  

Sample Answer

Yes. It is impossible to check pages manually where the entries contain many listings. PROC COMPARE will help you in such a case. (You can see that everything that you discussed in your previous response is captured here)

4.      You Must Have Come Across several Clinical Trials Studies. Could You Please Explain Some of The Types?

The interviewer wants to know about your background and experience in Clinical SAS. Such questions require you to go straight to the point. Also, make sure that you are honest with the interviewer.

Sample Answer

I have been in this field for quite some time, and therefore, have come across many clinical trials studies. However, the most common are single-blind, double-blind, and triple-blind studies. The first one is usually conducted where the patients do not know the treatment they are supposed to receive. Double-blind studies are done when both the patients and investigator do not know the assigned treatment group. Tripple blind is quite intense and occurs where the patient, investigator, and project team do not know the treatments administered.

5.      How Different is Program Validation from Macro Validation?

This is yet another technical question that seeks to unravel whether you understand the specific concepts in Clinical SAS. Like the previous recommendations, the best response is to go straight to the point and give the correct answer. Remember, there can only be one answer for technical questions.

Sample Answer

Program validation is similar to macro validation, just that the latter deals with programs. According to the standard operating procedures, one must first determine the program objective, see whether it will work as planned, and then create a validation document to capture whether the programs work properly. The last steps are to set the project status (which can either be pass or fail), passing the input parameters, and checking the log for errors.

6.      What Is Your Experience with Transport Files?

The interviewer wants to know whether you have created transport files in your career. Show them that you can do that effectively by explaining what they entail. Your answer should be convincing to the interview panel.

Sample Answer

I have created several SAS Xport files through Proc Copy, and data step for FDA submissions. Given that these are version 5 files, I usually use lib name engine and Proc copy procedure. The labels are usually shorter than 40 bytes, the variable names are 8 bytes, and the character variable width is usually confined to 300 bytes. All these constraints help prevent the termination of the copy procedure.

7.      Tell Us What You Know about ISS and ISE

The interviewer is gauging your knowledge on a particular concept of Clinical SAS. You must have interacted with ISS and ISE. Give a conclusive and convincing answer to the interviewer. Be as detailed as possible when answering such questions.

Sample Answer

ISS, which stands for integrated summary of safety, integrates safety information from animal, clinical pharmacology, epidemiological data, and an array of other sources. It, therefore, sums up data from several sources and focuses on analyses beyond individual studies. ISE, on the other hand, is the integrated summary of efficacies. Both are required in the safety and effectiveness submissions and must be submitted in the application. They integrate different data analyses and do not summarize them as most people would want to believe.

8.      What Do You Understand by SAS Documentation?

You should expect lots of questions testing your understanding of different concepts in Clinical SAS interviews. The best approach when answering such questions is to offer as much information as possible, which will convince the interviewer that you have a great understanding of what the question needs. In this case, explain to the interviewer what SAS documentation means.

Sample Answer

SAS documentation refers to anything typed in the program to make it easily readable and understandable. It, therefore, consists of the programmer header, titles, footnotes, comments, among many other things.

9.      Kindly Mention the Contents of Lab Data and Also Tell Us the Purpose of Data Set

Do you know what lab data contain? This is a technical question on a specific thing that you encounter in your work. Your answer will convince the interviewer that you are experienced and well learned. Keep it brief.

Sample Answer

The lab data set consists of the SUBJID, standard units, lab test category, week number, and low, normal, and high range of values. The lab data set helps obtain the difference in values of the critical variables once a drug has been administered.

10. Have You Ever Created CRTS? If yes, Please Tell Us.

CRTs are patent profile tabulations that Clinical SAS programmers are required to come up with in their operations. Tell the interviewer about your experience in creating patient listings.

Sample Answer

I have created several patient profile tabulations in my career. These came after the managers and statisticians requested me. I have also used PROC CONTENTS and PROC SQL to develop simple listings containing various patient information such as sex, race, and age.

11. How Would You Perform a Validation for a Listing of Over 400 Pages?

This is an operational question that seeks to understand your modes of operation and whether you are competent enough for the job. Kindly convince the interviewer that you understand how things are done and explain your mode of operation.

Sample Answer

Given the number of pages in the listing, manual validation is out of the question. I will, therefore, convert the listing in data sets through PROC REPORT and then compare it using PROC COMPARE afterward. Manual listing only works when dealing with a few pages.

12. Could You Define the Ideal Project Group in Clinical SAS?

Teamwork is one of the most critical aspects of Clinical SAS. The interviewer must therefore assess whether you know how teams work and who is involved. Therefore, mention the composition of your project group, how you think they should operate, and who you would contact in case of any issue.

Sample Answer

My ideal project group is one where everybody is free and open with information. I also love being around supportive people. As for the constituents, I believe that six members are enough. An ideal group should have a project manager, two programmers, a lead programmer, and two statisticians. I expect to report to the lead programmer in case of any programming issue and the statistician if I am having trouble with the values of the variables in the raw data set. Every group member should also be willing to go above and beyond for the other for a group to be ideal.

13. Why Is Verification Very Important?

You must have seen us mention verification several times in our article. It is an essential procedure in Clinical SAS that programmers are required to perform. The best way to answer such a question is to think about how verification helps you and the entire team in your day-to-day job.

Sample Answer

Verification plays a massive role in Clinical SAS since it ensures that the final tables are accurate and the SAS programs generated in the final tables are of high quality. Usually, the subset of the final summary tables is selected for verification. The verification results are also usually further verified with the original file tables to screen any elusive error.

14. Mention Some of The Necessary Roles That Individuals in Clinical SAS Play

There are normally two primary parties in clinical SAS: the programmer and the clinical study team. You must show the interviewer that you understand the roles of both and how they contribute to the success of whatever Clinical SAS stands for. If you are a programmer or part of a clinical study team, mention some of the things that you are mandated within your workplace.

Sample Answer

There are two main characters in clinical SAS- the programmer and the clinical study team. The programmer develops programs for report formats as dictated by the regulatory authorities. They also update ISS and ISE shells when necessary.

On the other hand, the clinical team offers necessary information on safety and efficacy findings as well as updates on the same for reporting purposes. The study statistician may also be part of this team. Their primary role is to draft ISS and ISE shells and update them when necessary. Other roles include analyzing and reporting data in approved formats and meeting periodic reporting requirements.

15. Can You Tell Us the Variables in All the Domains?

There are six domains in clinical SAS. The interviewer wants to know just how good you are when it comes to them. Answer this question confidently and exhaust all the domains, tackling one after the other. This should be easy to answer.

Sample Answer

For Demog, we have the Patient ID, age, race screening height and weight, BMI… For Adverse Events, there is the protocol number, patient ID, Investigator Term, Seriousness, Visit Number, Stop and Start Time, and the preferred term. For Vitals, there is the subject number, BMI, systolic and diastolic blood pressure, visit number…For ECG, we have the study date and time, QRS duration, QT and QTc interval, change from baseline, and ventricular rate… For Labs, we have the lab parameter and units, subject number, date of diagnosis, past conditions, visit number, and…PhysicalExam has the subject number, visit number, exam time and reason, findings, and…

16. As a Clinical SAS Programmer, How Do You Feel About Coding?

This is a general question that can pop up in your interview. You know yourself better than anyone else and can therefore establish whatever works for you. Be honest when answering this question but do not throw yourself under the bus and ruin your chances.

Sample Answer

I love coding. At times we have to hardcode to come up with an urgent report. Whereas this is understandable, I believe that one should not get too used to hardcoding as it overrides database controls in clinical data management. The complex code may also not be applicable in the future, given the constant data changes. If it is forgotten and left in the program, one may result in an incorrect database change, which can be costly.

17. How Do You Normally Write a Test Plan?

This is an operational question, which is usually asked to unravel how you go about your work. Your answer will help the interviewer gauge how good you are at this job. The best approach is to give a step-to-step procedure on how you come up with test plans.

Sample Answer

Before writing a test plan, I usually understand the requirements and functional specifications for writing the test plan. I, therefore, first look at the functional specifications, which by a large percentage depends on the requirement.

18. What Do You Understand by Macro Libraries?

What do you know about macro libraries? What are they used for? Your response will help the interviewer learn if you know specific things about Clinical SAS that you will be rubbing shoulders with.

Sample Answer

As the name suggests, macro libraries are used to store macros required for the development of the TLG’s of the clinical trial. They, therefore, play an essential role in the control and management of the macros. The stored macros in the library can be easily called through the %INCLUDE statement.

19. What Is the Use of ODS?

This is a technical question that seeks to ascertain whether you understand some of the systems or technologies required for this role. Be brief and go straight to the point.

Sample Answer

ODS, fully known as output delivery system, is usually used to better the output from the graphs, listings, and tables. The outputs are created in HTML, pdf, and RTF formats.

20. Have You Ever Interacted with PROC LIFE TEST? What Do You Normally Use It For?

There are several commands in Clinical SAS that you should be acquainted with. This is a technical question that will reveal to the interviewer your knowledge about the particular subject.

Sample Answer

Yes. I have used the command for Kaplan-Meier and life table estimates. This is made possible by the strata statement in the command, which compares the survival estimates for different groups.


You must have observed that most clinical SAS interview questions are technical. Therefore, make sure that you have the right amount of knowledge of different concepts before your interview. Also, make sure that your answers are concise and straight to the point. We wish you well in your interview.

Recent Posts