Quantitative Research Key Terms

Client-Centered Practice

practice in which the client is considered the expert regarding their situation and is the primary decision maker for health-care choices

Control

a condition that remains constant or the same between groups or situations

Critically Appraised Paper

a type of analysis that critiques a published research study and interprets the results for practitioners

Critically Appraised Topic

a type of analysis that critiques multiple published research studies on a topic and interprets the results for practitioners

Cross-Sectional Research

a type of study that collects data at a single point in time

Evidence-Based Practice

the process of using the research evidence, practitioner experience, and the client's values and desires to make the best clinical decisions

Incidence

the risk of developing a condition within a period of time or the frequency of new cases of a health condition within a specified time period

Internal Validity (of a study)

the ability to draw conclusions about causal relationships; in the case of intervention research, the ability to draw conclusions as to whether the intervention was effective

Levels of Evidence

a hierarchical approach that rates research evidence from strongest to weakest

Longitudinal Research

a study in which data are collected over at least two time points and typically cover an extended period of time, such as several years or decades, with the purpose of examining changes over time

PICO Question Format

a type of research question used to answer efficacy questions; includes the population or problem, intervention, comparison, and outcome

Prevalence

the proportion of individuals within a population who have a particular condition

Random Assignment

when research participants are assigned to groups in such a way that each participant has an equal chance of being assigned to the available groups

Randomized Controlled Trial

a type of research design that includes at least two groups (typically an experimental group and a control group), and participants are randomly assigned to the groups.

Reflective Practitioner

a practitioner who intentionally approaches clinical situations with an inquisitive mind and considers past experiences when making decisions

Reliability

the consistency and accuracy of a measure

Replication

conducting a study that duplicates most or all the features of a previous study

Scientific Method

an approach to inquiry that requires the measurement of observable phenomena

Sensitivity

the accurate identification of individuals who possess the condition of interest

Shared Decision-Making

process of making health-care decisions that includes the clinician and the client as equal partners

Specificity

the correct identification of individuals who do not have a condition

Systematic Review

a methodical synthesis of the research evidence regarding a single topic that can be replicated by others

Validity

in the case of a measure, the ability of that measure to assess what it is intended to measure. In the case of a study, when the conclusions drawn are based on accurate interpretations of the study findings and not confounded by alternative explanations

Boolean Operators

the words used in a database search for relating key terms, including AND, OR, and NOT

Database

an organized collection of data. In the case of evidence-based practice, a bibliographic citation is a compilation of articles, books, and book chapters

Impact Factor

importance of a journal based on the average number of times articles in that journal are cited in other articles

Institutional Animal Care and Use Committee

the organization that review and approves the ethical practices associated with animal research.

Institutional Review Board

the organization that reviews and approves the ethical practices of research studies that use human participants

Peer-Review Process

an appraisal process that uses experts in the field to determine whether an article should be published in a scientific journal.

Predatory Journals

journals that are primarily concerned with making a profit and take advantage of faculty under pressure to publish by requiring a fee in exchange for a quick acceptance to publication time

Primary Source

research studies and professional and governmental reports that are based on original research or data collection

Publication Bias

the tendency of scientific journals to publish positive findings ad reject negative findings

Secondary Source

documents or publications that interpret or summarize a primary source.

Trade Journals

magazines typically written by paid staff within an organization that do not undergo a peer review process

Applied Research

research that has direct application to health-care practices

Basic Research

investigation of fundamental questions that is directed toward better understanding of individual concepts

Categorical Variable

variables that describe attributes but do not have a quantitative value (e.g., gender, political affiliation)

Continuous Variable

data with values that fall on a continuum from less to more

Control Group

a group in which participants receive an alternate intervention, a standard intervention, or no intervention

Control Variable

a variable that remains constant or the same between groups or situations

Correlational Studies

a study designed to determine whether a relationship exists between two constructs and, if so, to assess the strength of that relationship.

Cross-Sectional Research

a type of study that collects data at a single point in time

dependent variable

the variable that is intended to measure the outcome of a study

Directional Hypothesis

a hypothesis in which the researcher makes an assumption or expresses belief in a particular outcome

Efficacy Studies

a study that examines whether an intervention has a positive outcome; typically conducted under ideal conditions to improve internal validity

Experimental Research

studies that examine cause-and-effect relationships

Extraneous Variable

typically conducted under ideal conditions to improve internal validity

Factorial Design

a study with more than one independent variable, in which the interaction or impact of both independent variables can be examined simultaneously.

Hypothesis

a proposed explanation for some phenomenon

Independent Variable

A variable that is manipulated or compared in a study

Intervention Studies

a study that examines whether an intervention has a positive outcome

Longitudinal Research

a study in which data are collected over at least two time points and typically cover an extended period of time, such as several years or decades, with the purpose of examining changes over time

Nondirectional Hypothesis

an exploratory method of study, suggesting that the researcher does not have preconceptions about what the study results may be, but may assume that a difference or relationship exists

Nonexperimental Research

research that does not manipulate the conditions but rather observes a condition as it exists; used to answer descriptive and relationship questions

Nonrandomized Controlled Trial

a study in which at least two groups are compared, but participants are not randomly assigned to groups; also called a quasi-experiment.

Null Hypothesis

a research hypothesis tested with statistics that states there is no difference or no relationship

Observational Studies

research in which only the naturally occurring circumstances are studied, as opposed to assigning individuals to an intervention or research condition.

Pre-experimental Research

a research design in which a single group is compared before and after an intervention

Qualitative Research

a type of research that studies questions about meaning and experience

Quantitative Research

a type of research that uses statistics and describes outcomes in terms of numbers

Quasi-Experimental Study

a research design that compares at least two groups but does not randomly assign participants to groups; also called a nonrandomized controlled trial.

Randomized Controlled Trial

a type a research design that includes at least two groups (typically an experimental group and a control group), and participants are randomly assigned to the groups.

Research Design

the specific plan for how a study is to be organized and carried out

Research Hypothesis

the prediction the researcher makes about the outcomes of their study

Third Variable Problem

arises when two constructs may be related, but a third variable could account for the relationship or influence the relationship

Traditional Research

when findings from the laboratory are used to generate clincial research

True Experiment

a randomized controlled trial

Type I Error

a statistical conclusion error that occurs when the hypothesis is accepted, yet the hypothesis actually false

Type II Error

a statistical conclusion error that occurs when the hypothesis is rejected, yet the hypothesis is true

Variable

characteristic of people, activities, situations, or environments that is identified and/or measured in a study and has more than one value

Descriptive Statistics

statistics that provide an analysis of data to help describe, show, or summarize the data in a meaningful way such that, for example, patterns can emerge from the data

Frequencies

statistics that describe how often something occurs

Frequency Distribution

a graph used to depict a count

Histogram

a frequency distribution presented as a bar graph with the y axis representing the frequency and the x axis the values of the scores

Mean

same as average; a descriptive statistic that balances the scores above and below it.

Measures of Central Tendency

the location of the center of a distribution

Median

a descriptive statistic indicating the score value that divides the distribution into equal lower and upper halves of the scores.

Mode

the score value that occurs most frequently in the distribution

Normal Distribution

a type of frequency distribution that represents many data points distributed in a symmetrical, bell-shaped curve

Range

a descriptive statistic that indicates the lowest and highest scores

Skewed Distribution

a frequency distribution in which one tail is longer than the other

Standard Deviation

a descriptive statistic that expresses the amount of spread in the frequency distribution and the average amount of deviation by which each individual score varies from the mean

Standard Error of the Mean

an estimate of the standard deviation of multiple samples representing the standard deviation for the population.

Variability

the spread of scores in a distribution

Alpha

the level of significance that is used to determine if an analysis is statistically significant.

Analysis of Variance (ANOVA)

a statistic used when a researcher wants to examine the differences between groups

Analysis of Covariance (ANCOVA)

a statistic used when a researcher wants to examine differences and statistically control a variable that may affect the outcome of a study

Between-Group Comparison

comparison of the results of two or more groups

Chi-Square

a statistic used to compare the differences between groups when the data compared are frequencies

Confidence Interval (CI)

a reliability estimate that suggests the range of outcomes expected when an analysis is repeated

Dependent Sample t-test

a statistic that compares a dependent variable within the same group, either a pretest and posttest or two different measures

Effect Size (ES)

a statistic that describes the magnitude or strength of a statistic. It can refer to the magnitude of the difference, relationship, or outcome

Independent Sample t-test

a statistic that compares the difference in the mean score for two groups that are independent of, or unrelated to, each other.

Inferential Statistics

statistical techniques that use study samples to make generalizations that apply to an entire population

Kruskal Wallis Test

a nonparametric statistic used to compare the difference between three or more groups using rank ordered data

Level of Significance

also called alpha or , the level at which a statistic is identified as statistically significant; most typically set at less than 0.05