Evidence-Based Practice 1

a paradigm & life-long problem solving approach to clinical decision-making that involves the conscientious use of the best available evidence (including a systematic search for & critical appraisal of the most relevant evidence to answer a clinical question) with one's own clinical expertise and patient values & preferences to improve outcomes for individuals, groups, communities and systems.

evidence that is generated from rigorous research

evidence generated within a clinical practice setting from initiatives such as quality improvement, outcomes management, or EBP implementation projects.

the use of research knowledge, often based on a single study, in clinical practice.

• randomized controlled trial.
• a true experiment (i.e., one that delivers an intervention or treatment in which subjects are randomly assigned to control and experimental groups); the strongest design to support cause-and-effect relationships.

a longitudinal study that begins with the gathering of two groups of patients (the cohorts), one that received the exposure (e.g., to a disease) and one that does not, and then following these groups over time (prospective) to measure the development of different outcomes (diseases).

the use of process and outcomes data to coordinate and influence actions and processes of care that contribute to patient achievement of targeted behaviors or desired effects.

initiatives with a goal to improve the processes or outcomes of the care being delivered.

whether or not the results of the study were obtained via sound scientific methods.

the consistency of an instrument in measuring the underlying construct.

whether or not the effects of the study are appropriate for a particular patient situation.

a persistent questioning about how to improve current practices; a sense of curiosity.

a process in which clinical questions are phrased in a manner that yields the most relevant information from a search; P = Patient population, I = Intervention or issue of interest, C = Comparison intervention or status, O = Outcome, T = Time frame for I to achieve O.

a summary of evidence, typically conducted by an expert or expert panel on a particular topic, that uses a rigorous process (to minimize bias) for identifying, appraising, and synthesizing studies to answer a specific clinical question and draw conclusions about the data gathered.

a process of using quantitative methods to summarize the results from the multiple studies, obtained and critically reviewed using a rigorous process (to minimize bias) for identifying, appraising, and synthesizing studies to answer a specific question and draw conclusions about the data gathered. The purpose of this process is to gain a summary statistic (i.e., a measure of a single effect) that represents the effect of the intervention across multiple studies.

questions that need to be answered as a foundation for asking the searchable, answerable foreground question. They are questions that ask for general information about a clinical issue.

those questions that can be answered from scientific evidence about diagnosing, treating, or assisting patients with understanding their prognosis, focusing on specific knowledge.

a process in which clinicians gather data together using narrowly defined clinical parameters; it allows for an appraisal of the available choices of treatment for the purpose of finding the most appropriate choice of action.

a project, paper, study, etc. is reviewed by a person(s) who is a peer to the author and has expertise in the subject.

systematically developed statements to assist clinicians and patients in making decisions about care; ideally, the guidelines consist of a systematic review of the literature, in conjunction with consensus of a group of expert decision makers, including administrators, policy makers, clinicians, & consumers who consider the evidence & make recommendations.

concise overviews of a health topic

a summary of the content of an article.

interactive computer programs designed to assist healthcare providers in making clinical decisions.

contains reviews that are highly structured and systematic with evidence included or excluded on the basis of explicit quality criteria, to minimize bias.

refers to publications such as brochures and conference proceedings.

MEDLINE's controlled vocabulary: Medical Subject Headings.

a bibliography of controlled trials identified by contributors to the Cochrane Collaboration and others.

a bibliography of articles and books on the science of research synthesis.

a major biomedical & pharmaceutical database

those studies that are conducted for the purpose of describing the characteristics of certain phenomena or selected variables.

the extent to which it can be said that the independent variable (i.e., the intervention) causes a change in the dependent variable (i.e., outcome), and the results are not due to other factors or alternative explanations.

generalizability; the ability to generalize the findings from a study to the larger population from which the sample was drawn.

a planning meeting held for the purpose of designing a study & strategizing about potential funding as well as the roles of all investigators.

essential characteristics specified by investigator that (a) potential participants must possess in order to be considered for a study; (b) studies must meet to be included in a body of evidence.

investigator-identified characteristics that are (a) possessed by individuals who would exclude them from participating in a study; (b) specified to exclude studies from a body of evidence.

the extent to which an intervention is delivered as intended.

a study that is conducted for the purpose of describing the relationship between two or more variables.

a study that is conducted for the purpose of describing what variables predict a certain outcome.

the variable that is influencing the dependent variable or outcome; in experimental studies, it is the intervention or treatment.

the ability of a study design to detect existing relationships between or among variables.

assessments verifying that subjects have actually processed the experimental information that they have received or followed through with prescribed intervention activities.

Occurs when two factors are closely associated and the effects of one confuses or distorts the effects of the other factor on an outcome. The distorting factor is a confounding variable.

Those factors that interfere with the relationship between the independent and dependent variables.

The strongest type of experimental design for testing cause-and-effect relationships: true experi-ments possess three characteristics: (a) a treatment or intervention; (b) a control or comparison group; and (c) random assignment.

Evidence generated from at least one well-designed random-ized clinical trial (i.e., a true experiment).

The basis upon which a study is guided; its purpose is to provide a context for selecting the study’s variables, including how they relate to one another as well as to guide the development of an intervention in experimental studies.

The variable or mechanism through which an intervention works to impact the outcome in a study.

The variable or outcome that is infl uenced or caused by the independent variable.

The overall plan for a study that includes strategies for controlling confounding variables, strategies for when the intervention will be delivered (in experimental studies) and how often and when the data will be collected.

A study whose purpose is to test the effects of an intervention or treatment on selected outcomes. This is the strongest design for testing cause-and-effect relationships.

A study design in which data are collected but whose purpose is not to test the effects of an intervention or treatment on selected outcomes.

A study designed to observe an outcome or variable at a single point in time, usually for the purpose of inferring trends over time.

A longitudinal study that begins with the gathering of two groups of patients (the cohorts), one that received the exposure (e.g., to a disease) and one that does not, and then following these groups over time (prospective) to measure the development of different outcomes (diseases).

Divergence of results from the true values or the process that leads to such divergence.

The use of a strategy to randomly assign subjects to the experimental or control groups (e.g., tossing a coin).

A type of experimental study design that uses a before–after design for the first two experimental groups and an after-only design for the second experimental and control groups so that it can separate the effects of pretesting the subjects on the outcome measure(s).

A type of experimental design that tests the effects of an interven-tion or treatment but lacks one or more characteristics of a true experiment (e.g., random assignment; a control or compari-son group).

The occurrence of some event or program unrelated to the intervention that might account for the change observed in the dependent variable.

Developmental change that occurs, even in the absence of the  intervention.

When subjects in a study are similar on the characteristics that may affect the outcome variable(s).

A strategy introduced into a study that entails deliberately including a potential extraneous intrinsic or confounding variable in a study’s design in order to control its effects on the dependent or outcome variable.

A type of control strategy used in an experimental design that places subjects in equally distributed study groups based on certain characteristics (e.g., age) so that each study group will be similar prior to introduction of the intervention or treatment.

When subjects are lost from or drop their participation in a study (see loss of subjects to follow-up).

Participant scores that cluster toward the high end of a measure.

Participant scores that cluster toward the low end of a measure.

A test of an instrument’s stability over time assessed by repeated measurements over time.

Generalizability; the ability to generalize the fi ndings from a study to the larger population from which the sample was drawn.

The extent to which the findings from a study can be generalized or applied to the larger population (i.e., external validity).

Selecting subjects to participate in a study by using a random strategy (e.g., tossing a coin); in this method of selecting subjects, every subject has an equal chance of being selected.

A strategy that divides the study population into two or more sub-populations and then samples separately from each.

Variables that have ordered categories with intervals that cannot be quantifi ed (e.g., mild, moderate, or severe anxiety).

Data that is classifi ed into categories (e.g., gender, hair color) instead of being numerically ordered.

The consistency of an instrument in measuring the underlying construct.

A measure of an instrument’s reliability (e.g., often computed with a Cronbach alpha).

The extent to which an instrument’s subparts are measuring the same construct.

The degree to which two individuals agree on what they observe.

Research that involves the collection of data in nonnumeric form, such as personal interviews, usually with the intention of describing a phenomenon.

The point at which categories of data are full and data collection ceases to provide new information.

Description that does more than describe human experiences by beginning to interpret what they mean, involving detailed reports of what people say and do, incorporating the textures and feelings of the physical and social worlds in which people move, with reference to that context (i.e., an interpretation of what their words and actions mean).

Demonstrated by information that is sufficient for a research consumer to determine whether the findings are meaningful to other people in similar situations (analytic or theoretical vs. statistical generalizability).

Data that is collected for the purpose of improving the quality of healthcare or patient outcomes.

A summary of primary studies from which conclusions are drawn by the reviewer based on his or her own interpretations.

Rapid cycle improvement in healthcare settings in which changes are quickly made and studied.

A mechanism for determining which study designs have the most power to predict cause-and-effect. The highest level of evidence is systematic reviews of RCTs, and the lowest level of evidence is expert opinion and consensus statements.

Study findings that will directly influence clinical practice, whether they are statistically significant or not.

The results of statistical analysis of data are unlikely to have been caused by chance, at a predetermined level of probability.

The process of evaluating a study for its worth (i.e., validity, reliability, and applicability to clinical practice).

A type of research that retrospectively compares characteristics of an individual who has a certain condition (e.g., hypertension) with one who does not (i.e., a matched control or similar person without hypertension); often conducted for the purpose of identifying variables that might predict the condition (e.g., stressful lifestyle, sodium intake).

The absolute risk increase for an undesirable outcome is when the risk is more for the experimental/condition group than the control/comparison group.

Measures the strength of association and is the risk of the outcome in the exposed group (Re) divided by the risk of the outcome in the unexposed group (Ru). RR is used in prospective studies such as RCTs and cohort studies.

Proportion of risk for bad outcomes in the intervention group compared to the unexposed control group.

The odds of a case patient (i.e., someone in the intervention group) being exposed (a/b) divided by the odds of a control patient being exposed (c/d).

The number of people who would need to receive the experimental therapy to prevent one bad outcome or cause one additional good outcome.

The number of clients, who, if they received an intervention, would result in one additional person being harmed (i.e., having a bad outcome) compared to the clients in the control arm of a study.

A type of research that retrospectively compares characteristics of an individual who has a certain condition (e.g., hypertension) with one who does not (i.e., a matched control or similar person without hypertension); often conducted for the purpose of identifying variables that might predict the condition (e.g., stressful lifestyle, sodium intake).

An intensive investigation of a case involving a person or small group of persons, an issue, or an event.

Procedure used for determining the sample size needed for a study.

A sham medical intervention or inert pill; typically given to subjects in experimental research studies to control for time and attention spent with subjects getting the experimental intervention.