Institutional Subscriptions   Individual Subscriptions 
Editors/Authors   Librarians   Newsletter   Site Tour   A-Z Index   About   Contact Us   Help 
Log In | Log In via Athens
 
Disable Autosuggest
JAMAevidence Glossary

Terms are derived from Users' Guides to the Medical Literature: A Manual for Evidence-Based Practice, 2nd Edition, The Rational Clinical Examination: Evidence-Based Clinical Diagnosis and Care at the Close of Life: Evidence and Experience. Updated October 2014.
Download a PDF of the glossary (295 KB). (Adobe Reader is required to open or print PDF files.)



0-9   A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Z


M

Major depressive disorder
The official Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) diagnostic term for depression, a mood disorder marked by sadness, inactivity, difficulty with thinking and concentration, a significant decrease (or increase) in appetite and time spent sleeping, feelings of dejection and hopelessness, and sometimes suicidal thoughts or an attempt to commit suicide.

Malaria
A clinical syndrome that results from a parasitic infection of the blood caused by any of 5 Plasmodium species: falciparum, vivax, ovale, malariae, and knowlesi.

Malrotation
Improper rotation of a body part (eg, the intestines).

Manning criteria
Combinations of findings used to diagnose irritable bowel syndrome. See Table 55-2 in The Rational Clinical Examination.

MANTRELS
The MANTRELS mnemonic is a helpful tool used to diagnose appendicitis. This mnemonic is a part of the Alvarado clinical decision rule and examines 8 findings from the medical history or the examination. The various components are Migration, Anorexia-acetone, Nausea-vomiting, Tenderness in RLQ, Rebound pain, Elevation of temperature, Leukocytosis, and Shift to the left of normal WBC count. See Table 5-5 in The Rational Clinical Examination.

Marginal utility
The change in a person’s utility (preference or relative value) for an outcome as the outcome increases in magnitude.

Marie Curie nurses
Nurses working for Marie Curie Cancer Care, a charitable organization in the United Kingdom that provides nursing care, free of charge, to terminally ill people. Patients may choose to receive care in their homes or in 1 of 10 Marie Curie hospices.

Markov model
Markov models are tools used in decision analyses. Named after a 19th-century Russian mathematician, Markov models are the basis of software programs that model what might happen to a cohort of patients during a series of cycles (eg, periods of 1 year). The model allows for the possibility that patients might move from one health state to another. For instance, one patient may have a mild stroke in one 3-month cycle, continue with minimal functional limitation for a number of cycles, have a gastrointestinal bleeding episode in a subsequent cycle, and finally experience a major stroke. Ideally, data from randomized trials will determine the probability of moving from one state to another during any cycle under competing management options.

Matching
A deliberate process to make the study group and comparison group comparable with respect to factors (or confounders) that are extraneous to the purpose of the investigation but that might interfere with the interpretation of the study’s findings. For example, in case control studies, individual cases may be matched with controls on the basis of comparable age, gender, and/or other clinical features.

McGill Pain Questionnaire
The McGill Pain Questionnaire, asks patients to describe their subjective experience of pain using sensory, affective, and evaluative descriptors. It also uses an intensity scale and other questions to describe more fully the pain experience. The McGill Pain Questionnaire was designed to produce 3 quantitative measures of clinical pain: (1) a pain rating index, based on 2 numerical values assigned to each word descriptor; (2) a count of the number of words used; and (3) a present pain intensity using a 1- to 5-point intensity scale. For more information, see the following article for the questionnaire: Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain. 1975;1(3):277-299. [PMID: 1235985]

Meals-on-Wheels
Programs that deliver meals to individuals at home who are unable to prepare or purchase their own meals. The name is often used generically to refer to home-delivered meals programs, not all of which are actually named “Meals-on-Wheels.”

Median survival
Length of time that one-half of the study population survives.

MediCal
California’s Medicaid health insurance program for indigent patients.

Medical decision-making capacity
A requirement for informed consent to treatment, determined by the process of a patient’s decision making, not the decision itself. Capacity requires 4 abilities: (1) ability to appreciate the situation and consequences of treatment choices, (2) ability to understand all pertinent information, (3) ability to reason about potential risks and benefits, and (4) ability to communicate one's choice.

Medical parole
The procedure for securing a terminally ill inmate’s release from prison, also known as compassionate release.

Medical subject headings
The U.S. National Library of Medicine's controlled vocabulary used for indexing articles for MEDLINE/PubMed. MeSH terminology provides a consistent way to retrieve information that may use different terminologies for the same concepts.

Medicare Hospice Benefit
Under the US Medicare Hospice Benefit, hospices are reimbursed to provide a package of services that include physician, nursing, social work, home health aide, volunteer, physical therapy, occupational therapy, speech therapy, counseling, dietary, and spiritual professionals; medications related to the terminal illness; medical supplies and equipment; short general inpatient and respite care; 12 months of bereavement follow-up; and any other services reasonable and necessary for palliation of the terminal illness.

Medicare managed care
A program that coordinates all health care services an individual receives to maximize benefits and minimize costs.

Melena
The passage of black, tarry stools.

Member checking
In qualitative research, this involves sharing draft study findings with the participants to inquire whether their viewpoints were faithfully interpreted and to ascertain whether the account makes sense to participants with different perspectives.

Memorial Delirium Assessment Scale
Screening tool for delirium in which 8 symptoms of delirium are assessed on a scale of 0 (none) to 3 (severe). For more information, see the following Web site for the scale: http://symptomresearch.nih.gov/chapter_5/tools/mdas.htm.

Memorial Pain Assessment Card (MPAC)
A simple instrument designed to provide rapid evaluation of measurement of pain intensity, pain relief, and psychological distress. (See also Chapter 5, Managing an Acute Pain Crisis in a Patient With Advanced Cancer, Figure 5-1.) For more information, see the following article for the card: Fishman B, Pasternak S, Wallenstein SL, et al. The Memorial Pain Assessment Card. A valid instrument for the evaluation of cancer pain. Cancer. 1987;60(5):1151-1158. [PMID: 3300951]

Memorial Symptom Assessment Scale
Pain and symptom assessment tool that provides a validated method for rapid assessment of the patient; evaluation of the patient’s pain intensity; and degree of relief, mood, and pain descriptors. It takes only 15 seconds to complete, allowing for frequent repeated use. For more information, see the following article for the scale: Portenoy RK, Thaler HT, Kornblith AB, et al. The Memorial Symptom Assessment Scale: an instrument for the evaluation of symptom prevalence, characteristics and distress. Eur J Cancer. 1994;30A(9):1326-1336. [PMID: 7999421]

Memory disorders
Associated with delirium and memory impairment.

Memory Impairment Screen
A quick test of recall ability where a patient is asked to recall items representing 4 different categories. Its advantages include the simplicity of the approach and uncomplicated scoring.

Messenger RNA
A ribonucleic acid-containing single-strand copy of a gene that migrates out of the cell nucleus to the ribosome, where it is translated into a protein.

Meta-analysis
A statistical technique for quantitatively combining the results of multiple studies that measure the same outcome into a single pooled or summary estimate.

Meta-regression analysis
When summarizing patient or design characteristics at the individual trial level, meta-analysts risk failing to detect genuine relationships between these characteristics and the size of treatment effect. Furthermore, the risk of obtaining a spurious explanation for variable treatment effects is high when the number of trials is small and many patient and design characteristics differ. Meta-regression techniques can be used to explore whether patient characteristics (eg, younger or older patients) or design characteristics (eg, studies of low or high quality) are related to the size of the treatment effect.

Meta-synthesis
A procedure for combining qualitative research on a specific topic in which researchers compare and analyze the texts of individual studies and develop new interpretations.

Methadone
A synthetic opioid medication used in stable doses for pain relief in treatment of chronic pain, in maintenance doses for treatment of opioid addiction (by addiction specialists), and in gradually escalating doses for pain relief in treatment of terminal illness. It is usually administered orally, but in the latter situation, it can be given intravenously, although consultation with experts in pain management is advised.

Migraine
A neurological condition characterized by altered bodily perceptions, recurrent usually unilateral severe headaches, and nausea.

Migraine, acephalgic
An aura that occurs without headache. In these cases, most patients have a known history of migraine.

Migraine, classic
The classic migraine has an aura associated with headache. Patients with classic migraine describe visual auras as amorphous pattern of lights or jagged lines and colors "marching" through the binocular visual field, sometimes surrounding a central area of visual field loss.

Milan criteria
Applied as a basis for selecting patients with cirrhosis and hepatocellular carcinoma for liver transplantation. Patients remain eligible for transplantation if they have a single carcinoma lesion <5 cm on imaging or up to 3 lesions each <3 cm and no extrahepatic metastasis and no vascular invasion.

Mindfulness meditation
A process of developing careful attention to minute shifts in body, mind, emotions, and environs while holding a kind, nonjudgmental attitude toward self and others.

Minimal important difference
The smallest difference in a patient-important outcome that patients perceive as beneficial and that would mandate, in the absence of troublesome adverse effects and excessive cost, a change in the patient’s health care management.

Mini-Mental Status Examination (MMSE)
A brief 30-point test that is used to screen for cognitive impairment.

Mixed-methods study
A study that combines data collection approaches, sometimes both qualitative and quantitative, into the study methodology and is commonly used in the study of service delivery and organization. Some mixed-methods studies combine study designs (eg, investigators may embed qualitative or quantitative process evaluations alongside quantitative evaluative designs to increase understanding of factors influencing a phenomenon). Some mixed-methods studies include a single overarching research design but use mixed-methods for data collection (eg, surveys, interviews, observation, and analysis of documentary material).

Mobility limitation
Impaired ability to move around by one’s self.

Model
Often used to describe statistical regression analyses involving more than one independent variable and one dependent variable. This is a multivariable or multiple regression (or multivariate) analysis.

Model for End-Stage Liver Disease (MELD)
The Model for End-Stage Liver Disease is a numerical scale that is currently used by United Network for Organ Sharing for allocation of livers for transplantation. It is based on objective and verifiable medical data (patient’s age, international normalized ratio, serum bilirubin level, and serum creatinine level [or dialysis]) that summarize a patient’s risk of dying while awaiting liver transplantation.

Model Policy for the Use of Controlled Substances for the Treatment of Pain
Designed to provide state medical boards with information regarding the appropriate management of pain with opioids (and other medications with abuse potential) to be in compliance with state and federal laws and regulations. It defines inappropriate treatment as including “nontreatment, undertreatment, overtreatment, and continued use of ineffective treatments.” For more information, see the following Web site for the model guidelines: http://www.fsmb.org/pdf/2004_grpol_Controlled_Substances.pdf.

Modified Tursky Pain Descriptors Scale
A categorical measure of pain intensity. The Pain Perception Profile was developed by Tursky in 1976 as an instrument measuring the affective, sensory, and intensity dimensions of pain. The Memorial Pain Assessment Card has a modified version of the Tursky Pain Description Scale on one side. See also Memorial Pain Assessment Card and Chapter 5, Managing an Acute Pain Crisis in a Patient With Advanced Cancer, Figure 5-1.

Mortality
Measure of rate of death.

Mortality Probability Models (MPM) II
Models developed to assess the severity of illness and the likelihood of survival of patients in intensive care units. For more information, see the following article for the models: Lemeshow S, Teres D, Klar J, et al. Mortality Probability Models (MPM II) based on an international cohort of intensive care unit patients. JAMA. 1993;270(20):2478-2486. [PMID: 8230626]

Mucositis
Inflammation of the mucosal membranes lining the gastrointestinal tract. It often affects the mouth and pharynx of patients with head and neck cancer who undergo radiation therapy.

Multidimensional Assessment of Fatigue
A 16-item, self-administered tool that takes approximately 5 minutes to complete that assesses subjective aspects of fatigue, such as quantity, degree, distress, impact, and timing. For more information, see the following article for the tool: Stein KD, Jacobsen PB, Blanchard CM, et al. Further validation of the multidimensional fatigue symptom inventory-short form. J Pain Symptom Manage. 2004;27(1):14-23. [PMID: 14711465]

Multidimensional Fatigue Inventory
A 20-item self-report instrument that includes general fatigue, physical fatigue, mental fatigue, reduced motivation, and reduced activity. For more information, see the following article for the inventory: Smets EM, Garssen B, Bonke B, et al. The Multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue. J Psychosom Res. 1995;39(3):315-325. [PMID: 7636775]

Multidimensional Fatigue Symptom Inventory-Short Form
The Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) is a 30-item short form of the MFSI, an 83-item self-report measure designed to assess the principal manifestations of fatigue. Items are rated on a 5-point scale (from 0 indicating not at all to 4 indicating extremely) that indicates how true each statement was for the respondent during the last week. The MFSI-SF subscales are designed to assess general, physical, emotional, and mental manifestations of fatigue and vigor, an estimate of the patient’s energy level. For more information, see the following article for the inventory: Stein KD, Jacobsen PB, Blanchard CM, et al. Further validation of the multidimensional fatigue symptom inventory-short form. J Pain Symptom Manage. 2004;27(1):14-23. [PMID: 14711465]

Multiple regression
A type of regression that provides a mathematical model that explains or predicts the dependent or target variable by simultaneously considering all of the independent or predictor variables. See also Multivariate regression analysis.

Multiple treatment comparison (MTC) meta-analysis
Multiple treatment comparison (MTC) meta-analysis uses both direct (head-to-head) evidence as well as indirect evidence from randomized clinical trials to compare the relative effectiveness of all included interventions.

Multivariate regression analysis
A type of regression that provides a mathematical model that attempts to explain or predict the dependent variable (or outcome variable or target variable) by simultaneously considering 2 or more independent variables (or predictor variables). See also Multiple regression.

Murphy sign
Pain and arrested inspiration occurring when the patient inspires deeply while the examiner's fingers are hooked underneath the right costal margin.

Mutation
A rare variant in a gene, occurring in <1% of a population. See also Polymorphism.

Myalgia
Muscle discomfort.

Myerson sign
Persistent blinking during the Glabella tap test used to diagnose Parkinson disease.
Copyright © American Medical Association. All rights reserved.  |  JAMA  |  McGraw-Hill Global Education Holdings, LLC.
Privacy Notice. Any use is subject to the Terms of Use and Notice. Additional Credits and Copyright Information.
Your IP address is 54.166.111.111