HESI Nursing Research Exam

Correct answer: A. Level II

Explanation of the correct answer:

A. Level II

An experimental study in which subjects are randomly selected is considered Level II evidence according to the hierarchy of evidence. Level II typically includes well-designed randomized controlled trials (RCTs) and experimental studies. Randomization helps eliminate bias, and the experimental nature of the study allows researchers to establish cause-and-effect relationships between variables. This level of evidence is often used to guide clinical decision-making and establish best practices in nursing.

Why the other options are incorrect:

B. Level IV

Level IV refers to cohort or case-control studies, which are non-experimental and observational. These studies are used when randomization is not possible but still provide valuable evidence. However, they are a lower level of evidence compared to randomized controlled trials (Level II).

C. Level VI

Level VI refers to studies based on expert opinions, clinical experiences, or case reports. This is the lowest level of evidence, as it is based on individual expertise rather than systematic data collection or rigorous research designs.

D. Level VII

Level VII is typically associated with anecdotal evidence or expert opinions that have little or no scientific rigor. These sources are not considered strong evidence for making clinical decisions and are considered the weakest form of evidence.

Summary:

An experimental study in which subjects are randomly selected is classified as Level II evidence because it involves a randomized controlled trial (RCT), which is a rigorous study design capable of establishing causality. RCTs are considered one of the highest levels of evidence in the hierarchy, offering strong support for making clinical decisions.

Correct answers: B, C

Explanation of the correct answers:

B. Nonexperimental designs are used to test relationships among variables.

Nonexperimental designs are often used to examine relationships between variables, but they do not involve manipulation of the independent variable. Instead, researchers observe and measure variables as they naturally occur. This allows researchers to test whether and how variables are related, without attempting to influence or control them.

C. Nonexperimental designs can be used to construct a picture of a phenomenon at one point in time.

Nonexperimental designs, such as cross-sectional studies, are commonly used to gather data at one specific point in time. These studies provide a snapshot of a phenomenon or population at a particular moment, without manipulation or control over the variables.

Why the other options are incorrect:

A. In nonexperimental studies, the independent variable is manipulated.

This statement is false. In nonexperimental studies, the independent variable is not manipulated. Instead, researchers observe existing variables and their relationships without intervention. Manipulation of variables is characteristic of experimental designs, not nonexperimental ones.

D. In nonexperimental studies, subjects are randomly selected.

While random selection can occur in nonexperimental studies, it is not a defining characteristic. Nonexperimental studies often use convenience sampling or other nonrandom selection methods. Random selection is more closely associated with experimental or quasi-experimental designs to ensure generalizability.

Summary:

Nonexperimental designs are useful for testing relationships among variables (B) and for constructing a picture of a phenomenon at one point in time (C). However, they do not involve manipulation of the independent variable (A) or necessarily random selection of subjects (D).

Correct answer: C

Explanation of the correct answer:

C. It is manipulated by the researcher.

The independent variable is the one that is manipulated or controlled by the researcher in an experiment. It is the variable that is thought to have an effect on the dependent variable. In experimental studies, the researcher changes or manipulates the independent variable to observe how it impacts the dependent variable.

Why the other options are incorrect:

A. It is the variable that is predicted to change.

This is incorrect because the independent variable is the one that is manipulated by the researcher to cause change, not the one that is predicted to change. The dependent variable is the one that is predicted to change based on the manipulation of the independent variable.

B. It varies with a change in the dependent variable.

This is incorrect because the independent variable is not affected by the dependent variable; instead, the independent variable is thought to cause changes in the dependent variable. The dependent variable varies as a result of the changes made to the independent variable.

D. It can be identified only by changes in the dependent variable.

This is incorrect because the independent variable is identified by the researcher’s intentional manipulation of it. It is not identified by changes in the dependent variable; rather, it is the factor being tested to see if it causes changes in the dependent variable.

Summary:

The independent variable is the one that is manipulated by the researcher to observe its effect on the dependent variable. It is not the one predicted to change but is instead the cause of changes in the dependent variable.

Correct answer: B

Explanation of the correct answer:

B. Hypotheses are statements about the relationships among variables.

Hypotheses are essentially predictions or educated guesses about how variables are related to one another. They propose a relationship or an effect that is to be tested in a study. A good hypothesis suggests what the researcher expects to find in terms of the relationship between the independent variable (the variable that is manipulated) and the dependent variable (the variable that is measured or observed for changes).

Why the other options are incorrect:

A. Hypotheses operationally define the dependent variables.

This is incorrect because a hypothesis does not define the dependent variables; rather, it predicts the relationship or effect between variables. Operational definitions of variables are typically included in the methods section of a research study to clarify how variables are measured, not in the hypothesis itself.

C. Hypotheses describe the effect of the dependent variable on the independent variable.

This is incorrect because the dependent variable is the one that is affected by changes in the independent variable, not the other way around. A hypothesis typically predicts how the independent variable influences the dependent variable, not the reverse.

D. Hypotheses must include a definition of the treatment or intervention used.

While it's important to clearly define the treatment or intervention in a study, a hypothesis itself does not necessarily include this definition. The hypothesis is focused on predicting the relationship between variables, not specifically on defining the intervention. The methods section of the study would typically include the operational definitions of the treatment or intervention.

Summary:

A hypothesis predicts or suggests the relationship between variables and is not limited to defining variables or treatments. It is concerned with specifying how one variable (typically the independent variable) is expected to affect another variable (the dependent variable).

Correct answer: B

Explanation of the correct answer:

B. Meditation techniques found to be effective

This variable is the most relevant to explore because the nurse is interested in studying the effectiveness of meditation for people with anxiety disorder. Research on meditation techniques that have been proven effective for similar conditions, especially anxiety, would provide the nurse with a solid evidence base for understanding how meditation can be applied to this population. This will help determine what specific types of meditation (e.g., mindfulness, guided meditation) have demonstrated success in reducing anxiety symptoms.

Why the other options are incorrect:

A. Use of meditation during childbirth

Although meditation might be beneficial during childbirth, this is unrelated to the nurse's specific focus on anxiety disorders. The literature on meditation techniques for childbirth would not directly inform the study on meditation for anxiety disorders.

C. Pain management for people with anxiety disorders

While pain management may be important for some individuals with anxiety disorders, it is not the primary focus of this study. The nurse is interested in meditation as an intervention for anxiety, not necessarily for pain management, so this variable is not directly related.

D. Outcomes of meditation when used by elderly populations

While it is valuable to understand how meditation impacts different populations, the nurse is interested in people with anxiety disorders specifically. Elderly populations may have different needs and responses to meditation than those with anxiety disorders, so this may not be directly relevant to the nurse’s study of meditation for anxiety.

Summary:

The most relevant variable to explore is the meditation techniques found to be effective for anxiety disorders, as it aligns directly with the nurse's research interest in studying the effectiveness of meditation for people with anxiety.

Correct answers: A, C, D

Explanation of the correct answers:

A. A relationship between two or more variables

A sound research question must define a relationship between at least two variables. This relationship is crucial because it provides the foundation for the study, indicating what the researcher aims to examine, compare, or investigate. Without a relationship, the research question may lack focus and purpose.

C. The nature of the population being tested

The nature of the population being tested is an important consideration in the formulation of a research question. The research question should specify the population or sample from which data will be gathered. This is essential for understanding the applicability of the findings and for defining the boundaries of the study.

D. The possibility of empirical testing

A research question must be testable using empirical methods. This means the question should be framed so that it can be answered through direct observation, measurement, or experimentation. Empirical testing is essential for ensuring that the findings are based on objective data and not subjective opinions or assumptions.

Why the other option is incorrect:

B. An operational definition of each variable

While operational definitions are critical for conducting the research, they are not a requirement for judging the soundness of the research question itself. Operational definitions come into play during the design and methodology stages, but the research question itself should primarily focus on the variables and their relationship. An operational definition clarifies how the variables will be measured, but the research question must be clear and testable first.

Summary:

To judge the soundness of a research question, it is important to ensure there is a clear relationship between variables, the population is defined, and the question is empirically testable. While operational definitions are necessary for executing the study, they are not part of the initial criteria for the research question's soundness.

Correct answer: B. Eliminate bias

Explanation of the correct answer:

B. Eliminate bias

Random selection is a method used by researchers to eliminate bias in the selection of participants. By randomly selecting subjects, each individual has an equal chance of being chosen, which helps ensure that the sample is representative of the population and reduces the likelihood of biased results.

Why the other options are incorrect:

A. Increase the number of participants

While random selection can lead to an appropriately sized sample, its primary purpose is not to increase the number of participants. The focus of random selection is on reducing bias, not just increasing the number of participants.

C. Prevent contamination of subjects

Contamination of subjects refers to a situation where subjects from different groups influence each other, typically in experimental studies. Random selection does not directly prevent this, but rather helps ensure a more unbiased representation of the population.

D. Control the dependent variables

The dependent variable is influenced by the independent variable in a study. Random selection helps ensure that the sample is representative, but it does not control the dependent variable. Control of the dependent variable is done through study design and manipulation of the independent variable.

Summary:

The primary purpose of random selection is to eliminate bias by giving each subject an equal chance of being selected, ensuring the sample is representative of the larger population.

Correct answer: D. Experimental

Explanation of the correct answer:

D. Experimental

A prospective study is most commonly associated with experimental research, particularly in clinical trials and intervention-based studies. In a prospective study, researchers identify participants and follow them forward in time to observe outcomes as they occur. This forward-looking approach aligns with experimental designs where researchers implement an intervention (manipulating the independent variable) and track its effects on the dependent variable over time.

For instance, in a clinical trial testing a new drug, participants are assigned to treatment or control groups, and the outcomes are tracked prospectively—this is both experimental and prospective in design. Although prospective studies can be observational, when they include manipulation and randomization, they fit the experimental category.

Why the other options are incorrect:

A. Survey

Surveys are typically cross-sectional, collecting data at one point in time to describe attitudes, behaviors, or characteristics. While a survey could be part of a prospective design if administered repeatedly, surveys themselves are not inherently prospective in nature.

B. Correlational

Correlational studies investigate relationships between variables without manipulation. They can be either cross-sectional or prospective, but they do not involve interventions or experimental control. While some prospective studies may use a correlational design, prospective studies that involve intervention and control are experimental by nature.

C. Developmental

Developmental studies focus on changes over time in individuals or groups. While they often adopt a prospective approach (such as longitudinal studies), their primary purpose is to understand developmental processes rather than test interventions. Therefore, they are not inherently experimental unless they include manipulated variables.

Summary:

A prospective study is best classified as experimental when it involves intervention and follows subjects over time to observe outcomes. Although prospective designs can be used in observational research, when manipulation and control are present—as is typical in clinical trials—they are distinctly experimental. Therefore, the correct answer is D. Experimental, while survey, correlational, and developmental studies do not inherently reflect prospective experimental research.

Correct answer: D. Mortality

Explanation of the correct answer:

D. Mortality

In research, mortality refers to the loss of study participants over time, especially before the completion of data collection. This is also known as attrition. It is a threat to the internal validity of a study because it can lead to biased results if the participants who drop out differ significantly from those who remain. For instance, if sicker patients are more likely to leave a clinical trial, the outcomes may appear better than they truly are, since the remaining participants are healthier on average.

This is particularly problematic in longitudinal studies or clinical trials where participation occurs over weeks, months, or even years. Researchers must account for and report dropout rates, and sometimes perform statistical adjustments (e.g., intention-to-treat analysis) to mitigate the effects of attrition.

Why the other options are incorrect:

A. History

History refers to external events that occur during the course of a study and may affect the outcome. For example, if a national health campaign starts while a researcher is studying diet behavior, it could influence participants' eating habits, thus confounding the results.

B. Maturation

Maturation refers to changes within the participants themselves over time, such as aging, healing, or fatigue, that could influence the outcome of the study. For example, in a study on developmental progress in children, natural aging and cognitive development may influence results independent of the intervention.

C. Selection bias

Selection bias occurs before the study begins, when there is a systematic difference in how participants are selected or assigned to groups, leading to groups that are not comparable. For example, if healthier individuals are more likely to enroll in a study, the results may not be generalizable.

Summary:

Mortality refers specifically to participant dropout and can threaten the validity of a study’s results by reducing sample size and introducing bias. Unlike history, maturation, or selection bias, which influence the study in other ways, mortality directly affects the continuity and completeness of data collection.: D. Mortality

Explanation of the correct answer:

D. Mortality

In research, mortality refers to the loss of study participants over time, especially before the completion of data collection. This is also known as attrition. It is a threat to the internal validity of a study because it can lead to biased results if the participants who drop out differ significantly from those who remain. For instance, if sicker patients are more likely to leave a clinical trial, the outcomes may appear better than they truly are, since the remaining participants are healthier on average.

This is particularly problematic in longitudinal studies or clinical trials where participation occurs over weeks, months, or even years. Researchers must account for and report dropout rates, and sometimes perform statistical adjustments (e.g., intention-to-treat analysis) to mitigate the effects of attrition.

Why the other options are incorrect:

A. History

History refers to external events that occur during the course of a study and may affect the outcome. For example, if a national health campaign starts while a researcher is studying diet behavior, it could influence participants' eating habits, thus confounding the results.

B. Maturation

Maturation refers to changes within the participants themselves over time, such as aging, healing, or fatigue, that could influence the outcome of the study. For example, in a study on developmental progress in children, natural aging and cognitive development may influence results independent of the intervention.

C. Selection bias

Selection bias occurs before the study begins, when there is a systematic difference in how participants are selected or assigned to groups, leading to groups that are not comparable. For example, if healthier individuals are more likely to enroll in a study, the results may not be generalizable.

Summary:

Mortality refers specifically to participant dropout and can threaten the validity of a study’s results by reducing sample size and introducing bias. Unlike history, maturation, or selection bias, which influence the study in other ways, mortality directly affects the continuity and completeness of data collection.