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LEGEND Glossary Let Evidence Guide Every New Decision LEGEND Glossary Let Evidence Guide Every New Decision A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A Adverse Event An adverse outcome occurring during or after the use of a drug or other intervention Related Terms but not necessarily caused by it. Side Effect Serious Adverse Event Adverse Drug Event Source/Copyright © Bandolier Glossary & The Cochrane Collaboration Glossary Applicability The extent to which the study results or effects of the study are appropriate and Related Terms relevant for use in a particular patient situation External Validity Internal Validity (e.g., patient characteristics, clinical setting, resources, organizational issues) Validity Reference Population Source/Copyright © The Cochrane Collaboration Glossary Attrition The loss of participants during the course of a study due to withdrawals, dropouts, or Synonyms protocol deviations which potentially introduces bias by changing the composition of Dropout the sample. Related Terms Lost to Follow Up Source/Copyright © The Cochrane Collaboration Glossary & Portney, Leslie. G. & Watkins, Mary, P. Foundations of Clinical Research Application to Practice. 2nd Edition. 2000. Prentice Hall Health. Upper Saddle River, New Jersey 07458. B Baseline Data Data which measures the outcome of interest prior to initiating any change or Related Terms intervention Baseline Characteristics Source/Copyright © The Cochrane Collaboration Glossary & Portney, Leslie. G. & Watkins, Mary, P. Foundations of Clinical Research Application to Practice. 2nd Edition. 2000. Prentice Hall Health. Upper Saddle River, New Jersey 07458. C Case(s) A person having a particular disease, disorder, or condition Source/Copyright © International Epidemiological Association, Inc.: Porta, M., Greenland, S., & Last, J. M. (Eds.). (2008). A dictionary of epidemiology (5th ed.). New York, NY: Oxford. (Page 30) Case–Control Study A study which involves identifying patients who have the outcome of interest (cases) and patients without the same outcome (controls), and looking back to see if they had the exposure of interest Source/Copyright © Center for Evidence-Based Medicine, Toronto Copyright © 2005-2013 Cincinnati Children's Hospital Medical Center; all rights reserved. February 25, 2013 Page 1 of 16 CCHMC Evidence Collaboration: James M. Anderson Center for Health Systems Excellence | Center for Professional Excellence | Edward L. Pratt Research Library | Occupational Therapy & Physical Therapy | Hospital Medicine www.cincinnatichildrens.org/evidence LEGEND Glossary Let Evidence Guide Every New Decision Case Report A study reporting observations on a single individual Synonyms Case Study Single Case Related Terms Case History N–of–1 Source/Copyright © Center for Evidence-Based Medicine, Toronto Case Series A report on a series of patients treated in a similar manner without a control group Source/Copyright © American Medical Association & Center for Evidence-Based Medicine, Toronto Ceiling Effects Participants' scores that cluster toward the high end of a measure due to limitations in Related Terms the design of the instrument not the phenomenon being observed Floor Effects Source/Copyright © Cincinnati Children’s Hospital Medical Center Clinical Question A question developed to explore a focused clinical topic which contains specific Synonyms elements: a patient or population; an intervention or exposure; often a comparison; PICO Question Health Question and a specific outcome Source/Copyright © Cincinnati Children’s Hospital Medical Center Clinically Significant A result (e.g. a treatment effect) that is large enough to be of practical importance to Related Terms patients and healthcare providers, regardless of the degree of statistical significance. Statistically Significant Assessing clinical significance takes into account factors such as the size of a treatment effect, the severity of the condition being treated, the side effects of the treatment, and the cost. Source/Copyright © The Cochrane Collaboration Cohort Study An observational study in which a defined group of people (the cohort) is followed over Related Terms time. The outcomes of people in subsets of this cohort are compared, to examine Confounder people who were exposed or not exposed (or exposed at different levels) to a particular intervention or other factor of interest. A prospective cohort study assembles participants and follows them into the future. A retrospective (or historical) cohort study identifies subjects from past records and follows them from the time of those records to the present. Because subjects are not allocated by the investigator to different interventions or other exposures, adjusted analysis is usually required to minimize the influence of other factors (confounders). Source/Copyright © The Cochrane Collaboration Comorbidity The presence of one or more diseases or conditions other than those of primary Related Terms interest. In a study looking at treatment for one disease or condition, some of the Confounder Morbidity individuals may have other diseases or conditions that could affect their outcomes. (A co-morbidity may be a confounder.) Source/Copyright © The Cochrane Collaboration Copyright © 2005-2013 Cincinnati Children's Hospital Medical Center; all rights reserved. February 25, 2013 Page 2 of 16 CCHMC Evidence Collaboration: James M. Anderson Center for Health Systems Excellence | Center for Professional Excellence | Edward L. Pratt Research Library | Occupational Therapy & Physical Therapy | Hospital Medicine www.cincinnatichildrens.org/evidence LEGEND Glossary Let Evidence Guide Every New Decision Concurrent Validity Concurrent validity is demonstrated where a test correlates well with a measure that Synonyms has previously been validated. The two measures may be for the same construct, or for Convergent Validity different, but presumably related, constructs. Source/Copyright © The Free Dictionary – Medical Dictionary Confidence Interval (CI) Quantifies the uncertainty in measurement. It is usually reported as a 95% CI, which is Synonyms the range of values within which we can be 95% sure that the true value for the whole Confidence Limits population lies. Related Terms The CI reflects the precision of the result (e.g., odds ratio, relative risk). Wider CIs Measures of Statistical Uncertainty indicate less precision, narrow CIs indicate more precision. Precision Source/Copyright © Centre for Evidence-Based Medicine Toronto Conflict of Interest A situation in which an individual or group is involved in multiple interests (concerns), and one or more interests could possibly affect the motivation for an action or interpretation regarding another interest. Also, within the biomedical research and publishing enterprise, these conflicts may occur when investigators, authors, institutions, reviewers, and/or editors have financial or nonfinancial relationships with other persons or organizations (eg, study sponsors) or personal investments in research projects or the outcomes of projects that may inappropriately influence their interpretation or actions. Conflicts of interest can lead to biased design, conduct, analysis, and interpretation of study results. Source/Copyright © American Medical Association Confounder A factor that is associated with both an intervention (or exposure) and the outcome of Related Terms interest Adjusted Analysis Confounding is a major concern in non-randomized studies. Randomization is used to minimize imbalances in confounding variables between experimental and control groups. Confounders may be unequally distributed among the groups being compared and, if so, may distort the true relationship of the study variable of interest. Source/Copyright © The Cochrane Collaboration & American Medical Association Construct Validity Construct validity reflects the degree to which an instrument measures the Related Terms characteristic being investigated. Factor Analysis Concurrent Validity Predictive Validity Source/Copyright © Portney, Leslie. G. & Watkins, Mary, P. Foundations of Clinical Research Application to Practice. 2nd Edition. 2000. Prentice Hall Health. Upper Saddle River, New Jersey 07458. Control Group RCT/CCT: A group that does not receive the experimental intervention. In many Synonyms studies, the control group receives either usual care or a placebo. The arm that acts Comparison Group Control(s) as a comparator for one or more experimental interventions. Case-Control Study: The group without the disease or outcome of interest. Source/Copyright © The Cochrane Collaboration Copyright © 2005-2013 Cincinnati Children's Hospital Medical Center; all rights reserved. February 25, 2013 Page 3 of 16 CCHMC Evidence Collaboration: James M. Anderson Center for Health Systems Excellence | Center for Professional Excellence | Edward L. Pratt Research Library | Occupational Therapy & Physical Therapy | Hospital Medicine www.cincinnatichildrens.org/evidence LEGEND Glossary Let Evidence Guide Every New Decision Controlled Clinical Trial (CCT) In both RCT and CCT, the investigator assigns the intervention or exposure. However, in Synonyms CCT, allocation to treatment and control groups is not fully randomized or is less Quasi-Experimental Study Pseudo-Experimental Study rigorous (e.g., quasi-randomization, no randomization mentioned) and may introduce Clinical Trial bias into the study. Related Terms Nonrandomized Controlled Trial Source/Copyright © The Cochrane Collaboration Correlation The magnitude and direction (i.e., positive, negative) of the association between two
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