Question 1

Which of the following cohort designs has more than one level of treatment?
A) The posttest-only cohort design
B) The posttest-only cohort design with partitioned treatments
C) The pretreatment-posttreatment cohort design
D) The reversed-treatment pretest-posttest cohort design

Accepted Answer

The posttest-only cohort design with partitioned treatments has more than one level of treatment because different participants in the cohort receive different treatments. The other designs listed only have one level of treatment.

Question 2

The analysis of whether changes in one variable in a time series cause subsequent changes in another variable in the series is referred to as an analysis of concomitance in time series.

Accepted Answer

An analysis of concomitance in time series examines the relationship between two variables in a time series to determine if changes in one variable cause subsequent changes in the other.

Question 3

In the context of interpretable nonequivalent groups designs, _____ is the main problem with a reversed-treatment pretest-posttest design.
A) historical concern
B) pretest sensitization
C) selection-by-maturation interaction
D) ethical concern

Accepted Answer

D

Question 4

Time-series designs are a class of quasi-experimental designs in which comparisons are made between participants in nonrandomly formed groups.

Accepted Answer

Time-series designs involve repeated observations of the same variables (e.g., people, groups) over short or long periods of time, rather than comparisons between nonrandomly formed groups.

Question 5

X₁ O₁ is a diagram of a one-group posttest-only design, which is a type of uninterpretable nonequivalent groups designs.

Accepted Answer

The statement is true.

Question 6

Which of the following designs is an interpretable nonequivalent groups design?
A) The one-group posttest-only design
B) The pretest-posttest nonequivalent groups design with additional pretest
C) The posttest-only nonequivalent design comparing multiple active treatments
D) The one-group pretest-posttest design

Accepted Answer

The pretest-posttest nonequivalent groups design with additional pretest is an interpretable nonequivalent groups design because it includes a pretest for both groups, allowing for a comparison of the groups' initial levels, and it also includes a posttest for both groups, allowing for a comparison of the groups' outcomes. The additional pretest strengthens the design by allowing for a better assessment of the groups' initial equivalence. The other designs listed do not have a control or comparison group and therefore do not allow for an interpretation of the treatment effect.

Question 7

One way to reduce the threat of history to the internal validity of a simple interrupted time-series design is to add a second dependent variable that theoretically will not be affected by the treatment.

Accepted Answer

Adding a second dependent variable that is not affected by the treatment can help control for the influence of history on the outcomes of the study and increase the internal validity of a simple interrupted time-series design.

Question 8

In a time-series design, the point at which the treatment takes place is called a(n) _____.
A) control point of the series
B) intervention of the series
C) interruption of the series
D) change window of the series

Accepted Answer

The point at which the treatment takes place in a time-series design is referred to as an "interruption of the series," indicating a point where the normal flow of data is disrupted by the introduction of a treatment or intervention.

Question 9

A hallmark of a true experimental design is the random assignment of participants to various treatment conditions, allowing a researcher to control many of the threats to internal validity.

Accepted Answer

Random assignment is a crucial component of true experimental design as it helps to ensure that participants are similar across treatment conditions, which decreases the likelihood of confounding variables and helps to establish causal relationships. This helps to control for many threats to internal validity, such as selection bias and history effects. Therefore, random assignment is a hallmark of a true experimental design.

Question 10

Which of the following is a disadvantage of the one-group pretest-posttest uninterpretable design?
A) The lack of information about any possible difference in the groups that exist before treatment makes it difficult to attribute results to the treatment.
B) The lack of a comparison group makes it impossible to rule out threats to internal validity.
C) The lack of random assignment of participants to groups allows the possibility that the groups may have differed along a number of important dimensions.
D) The lack of a control group makes it impossible to determine-after comparing pretest-posttest observations-if a change has occurred.

Accepted Answer

The lack of a comparison group in the one-group pretest-posttest uninterpretable design makes it impossible to rule out threats to internal validity. Without a comparison group, it is difficult to determine if any changes observed are a result of the treatment or other extraneous factors.

Question 11

The pretest-posttest nonequivalent groups design is a stronger and more interpretable design than the posttest-only nonequivalent groups design because it allows for an examination of:
A) some of the posttreatment differences.
B) the results of the posttreatment analysis.
C) some of the pretreatment differences.
D) the results of the pretreatment analysis.

Accepted Answer

The pretest-posttest nonequivalent groups design allows for an examination of some of the pretreatment differences between the groups, which can help control for selection bias and increase the internal validity of the study. The posttreatment differences can also be examined, but this is not the main advantage of this design over the posttest-only nonequivalent groups design.

Question 12

An advantage of the true experimental design in field settings is that the random assignment of participants into groups is easily achievable.

Accepted Answer

Random assignment of participants into groups can be more challenging in field settings due to logistical constraints and ethical considerations, such as limitations on manipulating real-world contexts or intervening in ongoing situations.

Question 13

A true experimental design differs from a quasi-experimental design in terms of the _____.
A) random assignment of participants to conditions
B) manipulation of independent variables
C) comparisons between or among groups
D) systematic factors related to conditions

Accepted Answer

The random assignment of participants to conditions is a key characteristic of a true experimental design that distinguishes it from a quasi-experimental design. In a true experiment, participants are randomly assigned to different conditions, allowing for causal inferences to be made about the effects of the independent variable. In a quasi-experimental design, participants are not randomly assigned, which limits the ability to draw causal conclusions. While both true experimental and quasi-experimental designs involve the manipulation of independent variables and comparisons between groups, it is the random assignment that distinguishes the two types of designs. The answer is therefore A) random assignment of participants to conditions.

Question 14

One of the most functional reasons for choosing a true experimental design over a quasi-experimental design is often that of cost.

Accepted Answer

The cost of a true experimental design is often higher than that of a quasi-experimental design due to the need for random assignment, control groups, and manipulation of variables. Therefore, the statement is false.

Question 15

Time-series designs are characterized by:
A) observations taken solely before the treatment.
B) observations of the same participant or similar participants.
C) a single observation comparing two or more groups.
D) a possibility of selection effects.

Accepted Answer

Time-series designs involve taking multiple observations of the same participant or similar participants over time. This allows researchers to observe changes within the same individual or group before and after the treatment is introduced. Option A is incorrect because time-series designs involve observations taken both before and after the treatment. Option C is incorrect because time-series designs typically involve observations of a single group, rather than comparing multiple groups. Option D is not necessarily true for all time-series designs and is not a defining characteristic of this design.

Question 16

The broken line used in a diagram for a cohort design indicates that the two groups in the design are successive cohorts and not nonequivalent groups.

Accepted Answer

The broken line in a cohort design diagram represents the passage of time, indicating that the two groups are successive cohorts over time. This differs from a diagram for a nonequivalent groups design, which typically shows the two groups as parallel lines.

Question 17

In terms of the MAXMINCON principle, researchers using a quasi-experimental design can both minimize differences in the independent variable(s) and maximize error variance due to measurement issues.

Accepted Answer

The MAXMINCON principle aims to maximize the differences in the independent variable(s) (MAX), minimize error variance (MIN), and control extraneous variables (CON), not to minimize differences in the independent variable(s) or maximize error variance due to measurement issues.

Question 18

The usefulness of quasi-experimental designs for advancing knowledge is directly related to how thoroughly an investigator examines and controls for the:
A) results of the posttest analysis of a study.
B) measures to be used in a questionnaire to record responses.
C) method to be used for statistical analysis.
D) selection criteria used in forming the initial groupings.

Accepted Answer

Quasi-experimental designs are often used in situations where random assignment of subjects is not possible or ethical. However, to increase the internal validity of the study, it is important to carefully examine and control for the selection criteria used in forming the initial groupings. This includes ensuring that the groups are comparable in important ways, such as age, gender, and baseline levels of the outcome variable. By controlling for selection factors, the investigator can be more confident that any observed differences between the groups are due to the intervention or treatment being studied, and not due to pre-existing differences between the groups. Posttest analysis, questionnaire measures, and statistical analysis are also important considerations in designing a quasi-experimental study, but are not as directly related to the internal validity of the study as the selection criteria.

Question 19

In the context of the selection of participants for research, a selection-by-threat interaction effect occurs when the threats to internal validity operate similarly across treatment conditions.

Accepted Answer

A selection-by-threat interaction effect occurs when the threats to internal validity operate differently across treatment conditions, not similarly.

Question 20

Consider the following diagram of a quasi-experimental design: Non R O_A1 X O_B2 Non R O_A1 O_B2This design represents the _____. A) nonequivalent groups design with a proxy pretest measure B) pretest-posttest nonequivalent groups design with additional pretest C) reversed-treatment pretest-posttest nonequivalent groups design D) interpretable pretest-posttest nonequivalent groups design

Accepted Answer

This design is a nonequivalent groups design with a proxy pretest measure, indicated by the use of non-randomized groups (Non R) and the inclusion of a unique pretest (proxy pretest) measure (U1) before the intervention (X) and standard pretest and posttest measures (OS1, B1, A1, S1, B0).

Quiz 12: Quasi-Experimental and Longitudinal Designs: Examining Relationships in Applied Setting

Which of the following cohort designs has more than one level of treatment?

The analysis of whether changes in one variable in a time series cause subsequent changes in another variable in the series is referred to as an analysis of concomitance in time series.

In the context of interpretable nonequivalent groups designs, _____ is the main problem with a reversed-treatment pretest-posttest design.

Time-series designs are a class of quasi-experimental designs in which comparisons are made between participants in nonrandomly formed groups.

X1 O1 is a diagram of a one-group posttest-only design, which is a type of uninterpretable nonequivalent groups designs.

Which of the following designs is an interpretable nonequivalent groups design?

One way to reduce the threat of history to the internal validity of a simple interrupted time-series design is to add a second dependent variable that theoretically will not be affected by the treatment.

In a time-series design, the point at which the treatment takes place is called a(n) _____.

A hallmark of a true experimental design is the random assignment of participants to various treatment conditions, allowing a researcher to control many of the threats to internal validity.

Which of the following is a disadvantage of the one-group pretest-posttest uninterpretable design?

The pretest-posttest nonequivalent groups design is a stronger and more interpretable design than the posttest-only nonequivalent groups design because it allows for an examination of:

An advantage of the true experimental design in field settings is that the random assignment of participants into groups is easily achievable.

A true experimental design differs from a quasi-experimental design in terms of the _____.

One of the most functional reasons for choosing a true experimental design over a quasi-experimental design is often that of cost.

Time-series designs are characterized by:

The broken line used in a diagram for a cohort design indicates that the two groups in the design are successive cohorts and not nonequivalent groups.

In terms of the MAXMINCON principle, researchers using a quasi-experimental design can both minimize differences in the independent variable(s) and maximize error variance due to measurement issues.

The usefulness of quasi-experimental designs for advancing knowledge is directly related to how thoroughly an investigator examines and controls for the:

In the context of the selection of participants for research, a selection-by-threat interaction effect occurs when the threats to internal validity operate similarly across treatment conditions.

Consider the following diagram of a quasi-experimental design: Non R OA1 X OB2 Non R OA1 OB2 This design represents the _____.

X₁ O₁ is a diagram of a one-group posttest-only design, which is a type of uninterpretable nonequivalent groups designs.

Consider the following diagram of a quasi-experimental design: Non R O_A1 X O_B2 Non R O_A1 O_B2This design represents the _____.