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Practice Exam
Question 1. Which phase of a clinical trial is primarily concerned with assessing safety and tolerability in a small number of healthy volunteers? A) Phase I B) Phase II C) Phase III D) Phase IV Answer: A Explanation: Phase I trials enroll a limited number of healthy subjects (or patients) to evaluate safety, tolerability, pharmacokinetics, and pharmacodynamics. Question 2. In the clinical trial data flow, which component typically receives raw eCRF data directly from sites? A) SDTM database B) Clinical Data Management System (CDMS) C) SAS analysis library D) Regulatory submission portal Answer: B Explanation: The CDMS captures electronic case report form (eCRF) entries at the site level and stores the raw data before transformation. Question 3. What is the primary responsibility of a SAS programmer on a clinical trial team?
Practice Exam
A) Designing the study protocol B) Conducting statistical hypothesis testing C) Transforming raw data into SDTM and ADaM datasets and creating TLFs D) Recruiting and consenting subjects Answer: C Explanation: SAS programmers manage data manipulation, create standard datasets (SDTM/ADaM), and generate tables, listings, and figures for analysis and reporting. Question 4. Which term describes the group of subjects who receive the investigational product as defined in the protocol? A) Control group B) Treatment group C) Placebo group D) Safety population Answer: B Explanation: The treatment group comprises subjects assigned to receive the investigational therapy per the randomization schedule. Question 5. In a clinical protocol, the “Visit” variable is best described as: A) The date a subject signs the informed consent B) A scheduled assessment point (e.g., Day 0, Week 4)
Practice Exam
Answer: B Explanation: FDA requires submission of standardized datasets following CDISC SDTM for tabulation and ADaM for analysis, typically in XPT transport files. Question 8. Which SAS statement is most appropriate for reading a fixed‑width ASCII file where each variable occupies a known number of columns? A) PROC IMPORT B) DATA step with INFILE and INPUT column pointer controls C) LIBNAME XLSX D) PROC IMPORT DATAFILE=... DBMS=CSV Answer: B Explanation: The DATA step with INFILE and column pointer controls (e.g., @ VAR1 3.) reads fixed‑width files efficiently. Question 9. To verify that a numeric variable “AGE” falls within the acceptable range of 18‑85, which SAS code fragment is correct? A) IF AGE < 18 OR AGE > 85 THEN DELETE; B) IF NOT (18 <= AGE <= 85) THEN FLAG=1; C) IF AGE NOT BETWEEN 18 AND 85 THEN CALL SYMPUT; D) IF AGE LT 18 OR AGE GT 85 THEN PUT 'ERROR'; Answer: B
Practice Exam
Explanation: The expression NOT (18 <= AGE <= 85) correctly flags ages outside the range. Question 10. Which PROC is most commonly used to create a frequency table of categorical variables in a clinical dataset? A) PROC MEANS B) PROC FREQ C) PROC UNIVARIATE D) PROC REPORT Answer: B Explanation: PROC FREQ produces counts and percentages for categorical data, essential for safety tables and baseline summaries. Question 11. When merging the Demographics (DM) domain with the Adverse Events (AE) domain, which key variable(s) should be used to ensure a correct one‑to‑many join? A) STUDYID only B) USUBJID and AESEQ C) USUBJID D) AESEQ only Answer: C Explanation: USUBJID uniquely identifies each subject; AE records are linked to the subject via this variable, creating a one‑to‑many relationship.
Practice Exam
A) Character variable containing the result text B) Numeric variable containing the result value C) Identifier for the subject D) Timing variable indicating visit day Answer: B Explanation: The “N” suffix denotes a numeric version of a result variable; the character counterpart would be “STRESC”. Question 15. Which ADaM dataset serves as the “subject‑level” analysis data set containing baseline demographics, treatment start dates, and analysis flags? A) BDS B) ADSL C) DM D) EX Answer: B Explanation: ADSL (Analysis Data Set – Subject Level) holds one record per subject with key analysis variables. Question 16. In a macro, the statement “%LET trt=PLACEBO;” creates a: A) Global macro variable named TRt with value PLACEBO B) Local macro variable that expires after the macro ends
Practice Exam
C) Global macro variable named TRT with value PLACEBO D) Data step variable called TRT Answer: C Explanation: %LET creates a global macro variable; the name is case‑insensitive, so TRT receives the value PLACEBO. Question 17. Which PROC can be used to compare two SAS datasets and produce a report of differences? A) PROC COMPARE B) PROC SORT C) PROC CONTENTS D) PROC PRINT Answer: A Explanation: PROC COMPARE evaluates two datasets and lists observations/variables that differ, useful for QC. Question 18. When applying a user‑defined format to a variable “AESEV” (severity), which PROC creates the format? A) PROC FORMAT B) PROC FREQ C) PROC SORT D) PROC TRANSPOSE
Practice Exam
Question 21. Which variable role in SDTM indicates the timing of an observation? A) Identifier (ID) B) Topic (T) C) Timing (TIM) D) Qualifier (Q) Answer: C Explanation: The TIMING role captures when an event occurred (e.g., VISITNUM, DTC). Question 22. To create a baseline flag variable “BASE” that equals 1 when the assessment occurs on Day 0, which SAS code is appropriate? A) IF DAY = 0 THEN BASE=1; ELSE BASE=0; B) IF DAY EQ '0' THEN BASE='Y'; C) BASE = (DAY=0); D) BASE = (DAY='0'); Answer: C Explanation: The expression (DAY=0) evaluates to 1 (true) or 0 (false), creating the flag efficiently.
Practice Exam
Question 23. Which PROC is best suited for generating a box plot of laboratory values by treatment group? A) PROC SGPLOT B) PROC UNIVARIATE C) PROC ANOVA D) PROC REPORT Answer: A Explanation: PROC SGPLOT provides graphical procedures, including BOX plots, with grouping options. Question 24. In a macro loop, the statement “%DO i=1 %TO &n.;” will iterate how many times? A) n+1 times B) n times C) n‑1 times D) Indefinitely Answer: B Explanation: The loop runs from 1 through the value of macro variable N inclusive, giving N iterations. Question 25. Which CDISC domain stores information about concomitant medications?
Practice Exam
C) INPUT(date, DATE9.) D) FORMAT(date, DDMMMYY) Answer: B Explanation: The PUT function with DATE9. format returns a character representation like “15MAR2021”. Question 28. In an ADaM BDS dataset, the variable “AVISIT” typically represents: A) Actual visit number B) Analysis visit (e.g., “BASELINE”, “WEEK 4”) C) Visit date in SAS date format D) Investigator’s assessment code Answer: B Explanation: AVISIT is a character variable used for analysis, indicating the visit label (e.g., “BASELINE”, “WEEK 4”). Question 29. Which macro function returns the uppercase version of a string passed to it? A) %UPCASE B) %LOWCASE C) %STRIP D) %COMPRESS
Practice Exam
Answer: A Explanation: %UPCASE converts its argument to uppercase, useful for standardizing macro variable values. Question 30. In the context of blinding, a “double‑blind” study means: A) Only the subject is unaware of treatment assignment B) Only the investigator is unaware of treatment assignment C) Both subject and investigator are unaware of treatment assignment D) The data analyst is blinded, but the site staff are not Answer: C Explanation: Double‑blind design masks treatment allocation from both participants and investigators to reduce bias. Question 31. Which PROC can be used to produce descriptive statistics (mean, std, median) for a continuous variable grouped by treatment? A) PROC FREQ B) PROC MEANS with CLASS statement C) PROC UNIVARIATE without BY D) PROC PRINT Answer: B Explanation: PROC MEANS with a CLASS statement calculates statistics separately for each treatment group.
Practice Exam
A) NOPRINT
B) NOOBS
C) NODATE
D) NOPRINTLABEL
Answer: B Explanation: NOOBS removes the observation number column from the report output. Question 35. When creating a derived variable “TRTDUR” representing treatment duration in days, which SAS expression is appropriate? A) TRTDUR = ENDTC - STARTTC; B) TRTDUR = INTCK('DAY', STARTDT, ENDDT); C) TRTDUR = DATEDIFF(ENDDT, STARTDT); D) TRTDUR = ENDTC - STARTTC + 1; Answer: B Explanation: INTCK('DAY', ...) returns the number of whole days between two SAS datetime values, suitable for treatment duration. Question 36. In a macro, the statement “%IF &flag = Y %THEN %DO;” is an example of: A) Macro iteration B) Macro conditional logic
Practice Exam
C) Macro variable assignment D) Macro inclusion Answer: B Explanation: %IF … %THEN … implements conditional processing based on a macro variable’s value. Question 37. Which SAS procedure is most appropriate for generating a PDF report containing tables created with PROC REPORT? A) PROC PDF B) ODS PDF C) PROC PRINT D) PROC EXPORT Answer: B Explanation: ODS PDF opens a PDF destination, allowing PROC REPORT output to be written to a PDF file. Question 38. In ADaM, the variable “ANALYSISTYPE” typically indicates: A) Whether the record belongs to safety or efficacy analysis B) The statistical test used C) The type of analysis dataset (e.g., “BDS”, “ADSL”) D) The analysis population flag (e.g., “ITT”, “PP”)
Practice Exam
Explanation: VSSTRESN stores the numeric result; VSSTRESC would store a character version if needed. Question 41. Which PROC can be used to produce a histogram of a continuous variable with a normal curve overlay? A) PROC UNIVARIATE with HISTOGRAM and NORMAL options B) PROC SGPLOT with HISTOGRAM only C) PROC MEANS with HISTOGRAM option D) PROC FREQ with HISTOGRAM statement Answer: A Explanation: PROC UNIVARIATE’s HISTOGRAM statement can request a normal density overlay via the NORMAL option. Question 42. When using the ARRAY statement to recode a set of laboratory variables to “NORMAL” if they fall within reference ranges, which construct is most efficient? A) DO i=1 TO dim(labarray); IF labarray[i] < LRL[i] OR labarray[i] > URL[i] THEN labarray[i]=.; END; B) DO OVER labarray; IF labarray < LRL OR labarray > URL THEN labarray='NORMAL'; END; C) DO i=1 TO 10; IF lab1[i] ... END; D) DO ALL; IF N ... END; Answer: A
Practice Exam
Explanation: Using a DO loop with DIM to iterate over the array and compare each element to its corresponding lower/upper reference limits is the standard efficient method. Question 43. Which CDISC model is specifically designed for pre‑clinical (toxicology) data? A) SEND B) ADaM C) ODM D) SDTM Answer: A Explanation: SEND (Standard for Exchange of Nonclinical Data) is the CDISC standard for toxicology studies. Question 44. In a SAS macro, the statement “%GLOBAL studyid;” does what? A) Declares a macro variable that can be accessed in any macro or step after its creation B) Sets the value of STUDYID to missing C) Deletes the macro variable STUDYID D) Limits STUDYID to the current macro only Answer: A Explanation: %GLOBAL creates a macro variable with global scope, accessible throughout the SAS session.
