EPPP QUESTIONS: RESEARCH AND STATISTICS
QUESTIONS WITH VERIFIED ANSWERS | ALL TOPICS |
2026 EDITION
SECTION 1: RESEARCH DESIGN AND METHODOLOGY
Questions 1-20
1. A researcher is investigating a rare neurological syndrome and tracks three
affected individuals over a five-year period, collecting detailed qualitative
behavioral and neuroimaging data. What is the primary methodological
limitation of this research design?
A. Low external validity
B. High risk of carryover effects
C. Low internal consistency
D. High risk of experimenter bias
Correct Answer: A
Rationale: Case studies involving a very small, specific sample size offer rich detail
but heavily limit the ability to generalize the findings to the broader population. This
is a limitation of external validity .
2. An organizational psychologist evaluates a new workplace wellness initiative
by measuring employee job satisfaction scores monthly for six months before
the program starts and monthly for six months following the completion of the
program. This research structure is best classified as:
A. Regression discontinuity design
B. Factorial design
C. Time series design
D. Mixed design
Correct Answer: C
,Rationale: A time series design involves tracking trends over time by taking multiple
distinct observations both before and after a specific intervention is introduced. This
allows for assessment of whether the intervention produced a change in the trend .
3. A clinical trial evaluates the impact of treatment type (CBT vs. medication)
and client age group (adolescent vs. adult) on depression severity scores. The
study utilizes a 2 × 2 factorial design. Which of the following statements is true
regarding this design?
A. It evaluates two independent variables, each containing two levels
B. It evaluates four independent variables, each containing one level
C. It evaluates a single independent variable across four distinct measurement
periods
D. It evaluates four independent variables with two levels each
Correct Answer: A
Rationale: In factorial notation, the number of digits represents the number of
independent variables, and the value of each digit indicates how many levels that
specific variable has. A 2 × 2 factorial design has two independent variables, each
with two levels .
4. A developmental psychologist wants to completely minimize error variance
caused by individual participant differences while testing the cognitive effects
of three different educational mobile apps. Which design choice is most
appropriate?
A. Between-subjects design with random assignment
B. Cross-sectional design utilizing stratified sampling
C. Within-subjects design utilizing counterbalancing
D. Matched-subjects design
Correct Answer: C
Rationale: A within-subjects design uses the same participants across all conditions,
meaning each person acts as their own baseline control, and individual differences
are perfectly controlled. Counterbalancing must be used alongside it to eliminate the
risk of order effects .
,5. Which of the following is NOT a disadvantage of repeated measures designs?
A. Practice effects
B. Carryover effects
C. Autocorrelation
D. Multicollinearity
Correct Answer: D
Rationale: Repeated measures designs (within-subjects designs) have disadvantages
including practice effects, carryover effects, and autocorrelation. Multicollinearity is
not a disadvantage specific to repeated measures designs .
6. The Hawthorne Effect occurs when:
A. Research subjects act differently because of the novelty of the situation and the
special attention they receive as participants
B. Unintentional cues in the experimental environment affect the results of the study
C. The effects of one treatment impact the effects of subsequent treatments
D. Subjects act in ways consistent with their expectations rather than simply in
response to the experimental manipulation
Correct Answer: A
Rationale: The Hawthorne Effect occurs when research subjects act differently
because of the novelty of the situation and the special attention they receive as
research participants. This is a threat to external validity .
7. Demand characteristics refer to:
A. Subjects acting differently because of the novelty of the situation
B. Unintentional cues in the experimental environment or manipulation that affect or
account for the results of the study
C. The effects of one treatment impacting the effects of subsequent treatments
D. Improvements in performance resulting from opportunities to perform a behavior
repeatedly
, Correct Answer: B
Rationale: Demand characteristics are unintentional cues in the experimental
environment or manipulation that affect or account for the results of the study.
Subjects may have acted in ways consistent with their expectations rather than
simply in response to the experimental manipulation .
8. In an AB design, the dependent variable is measured:
A. Once
B. Twice - before and after the intervention
C. At regular intervals
D. Three times
Correct Answer: C
Rationale: In an AB design (a single-subject design), the dependent variable is
measured at regular intervals during both the baseline (A) and treatment (B) phases .
9. An ABAB design is looking for:
A. An increase in the baseline with the application of the treatment
B. A reversal effect when treatment is withdrawn
C. Both A and B
D. Neither A nor B
Correct Answer: C
Rationale: An ABAB design involves baseline (A), treatment (B), return to baseline
(A), and reintroduction of treatment (B). It looks for an increase in the desired
behavior with treatment application and a reversal when treatment is withdrawn .
10. Which of the following is a threat to external validity?
A. Maturation
B. History
QUESTIONS WITH VERIFIED ANSWERS | ALL TOPICS |
2026 EDITION
SECTION 1: RESEARCH DESIGN AND METHODOLOGY
Questions 1-20
1. A researcher is investigating a rare neurological syndrome and tracks three
affected individuals over a five-year period, collecting detailed qualitative
behavioral and neuroimaging data. What is the primary methodological
limitation of this research design?
A. Low external validity
B. High risk of carryover effects
C. Low internal consistency
D. High risk of experimenter bias
Correct Answer: A
Rationale: Case studies involving a very small, specific sample size offer rich detail
but heavily limit the ability to generalize the findings to the broader population. This
is a limitation of external validity .
2. An organizational psychologist evaluates a new workplace wellness initiative
by measuring employee job satisfaction scores monthly for six months before
the program starts and monthly for six months following the completion of the
program. This research structure is best classified as:
A. Regression discontinuity design
B. Factorial design
C. Time series design
D. Mixed design
Correct Answer: C
,Rationale: A time series design involves tracking trends over time by taking multiple
distinct observations both before and after a specific intervention is introduced. This
allows for assessment of whether the intervention produced a change in the trend .
3. A clinical trial evaluates the impact of treatment type (CBT vs. medication)
and client age group (adolescent vs. adult) on depression severity scores. The
study utilizes a 2 × 2 factorial design. Which of the following statements is true
regarding this design?
A. It evaluates two independent variables, each containing two levels
B. It evaluates four independent variables, each containing one level
C. It evaluates a single independent variable across four distinct measurement
periods
D. It evaluates four independent variables with two levels each
Correct Answer: A
Rationale: In factorial notation, the number of digits represents the number of
independent variables, and the value of each digit indicates how many levels that
specific variable has. A 2 × 2 factorial design has two independent variables, each
with two levels .
4. A developmental psychologist wants to completely minimize error variance
caused by individual participant differences while testing the cognitive effects
of three different educational mobile apps. Which design choice is most
appropriate?
A. Between-subjects design with random assignment
B. Cross-sectional design utilizing stratified sampling
C. Within-subjects design utilizing counterbalancing
D. Matched-subjects design
Correct Answer: C
Rationale: A within-subjects design uses the same participants across all conditions,
meaning each person acts as their own baseline control, and individual differences
are perfectly controlled. Counterbalancing must be used alongside it to eliminate the
risk of order effects .
,5. Which of the following is NOT a disadvantage of repeated measures designs?
A. Practice effects
B. Carryover effects
C. Autocorrelation
D. Multicollinearity
Correct Answer: D
Rationale: Repeated measures designs (within-subjects designs) have disadvantages
including practice effects, carryover effects, and autocorrelation. Multicollinearity is
not a disadvantage specific to repeated measures designs .
6. The Hawthorne Effect occurs when:
A. Research subjects act differently because of the novelty of the situation and the
special attention they receive as participants
B. Unintentional cues in the experimental environment affect the results of the study
C. The effects of one treatment impact the effects of subsequent treatments
D. Subjects act in ways consistent with their expectations rather than simply in
response to the experimental manipulation
Correct Answer: A
Rationale: The Hawthorne Effect occurs when research subjects act differently
because of the novelty of the situation and the special attention they receive as
research participants. This is a threat to external validity .
7. Demand characteristics refer to:
A. Subjects acting differently because of the novelty of the situation
B. Unintentional cues in the experimental environment or manipulation that affect or
account for the results of the study
C. The effects of one treatment impacting the effects of subsequent treatments
D. Improvements in performance resulting from opportunities to perform a behavior
repeatedly
, Correct Answer: B
Rationale: Demand characteristics are unintentional cues in the experimental
environment or manipulation that affect or account for the results of the study.
Subjects may have acted in ways consistent with their expectations rather than
simply in response to the experimental manipulation .
8. In an AB design, the dependent variable is measured:
A. Once
B. Twice - before and after the intervention
C. At regular intervals
D. Three times
Correct Answer: C
Rationale: In an AB design (a single-subject design), the dependent variable is
measured at regular intervals during both the baseline (A) and treatment (B) phases .
9. An ABAB design is looking for:
A. An increase in the baseline with the application of the treatment
B. A reversal effect when treatment is withdrawn
C. Both A and B
D. Neither A nor B
Correct Answer: C
Rationale: An ABAB design involves baseline (A), treatment (B), return to baseline
(A), and reintroduction of treatment (B). It looks for an increase in the desired
behavior with treatment application and a reversal when treatment is withdrawn .
10. Which of the following is a threat to external validity?
A. Maturation
B. History
