Scientific words and phrases can be difficult to understand for those outside of the scientific or medical community. Check this area for words commonly used in medical literature or oral presentations related to fibromyalgia. A better understanding of the terminology used by researchers and clinicians can help you make sense of information that might be beneficial in your treatment and, ultimately, to your quality of life.


Acetamininophen - A type of pain reliever that does not contain aspirin and does not need a prescription.

Acupressure -The application of pressure (as with the thumbs or fingertips) to the same discrete points on the body stimulated in acupuncture; used for therapeutic effects (as the relief of tension or pain).

Acupuncture - The ancient Chinese practice of inserting fine needles through the skin at specific points especially to cure disease or relieve pain.

Adherence -(Same as Compliance) How well the patient adheres to an agreed treatment plan.

Adverse Events - Negative side effects of a treatment.

Allodynia - A condition in which you have a painful reaction to a stimulus, such as a light touch on your skin, when you shouldn’t.

Alternative Medicine - Any of various systems of healing or treating disease (as homeopathy, chiropractic, naturopathy, Ayurveda, or faith healing) that are not included in the traditional curricula taught in medical schools of the United States and Britain.

American College of Rhrumatology (ACR) - The official organization for health-care professionals who treat arthritis and other rheumatic diseases. This organization established the criteria for diagnosing fibromyalgia.

Analgesic - A drug that helps reduce or eliminate the perception of pain.

Antidepressant - A prescription medication that is prescribed to relieve moodiness and depression. Some antidepressants can also promote sleep and help relieve pain.

Anti-Tumour NECROSIS FACTOR TNF is a chemical made by the body’s immune system. When it is made in the joints it causes the process of inflammation and joint damage, as in rheumatoid arthritis. It was first discovered many years ago in experiments on cancer, where it was found to cause cancer cells to die, and so it was called Tumour Necrosis (i.e. the death of a piece of bone or tissue) Factor.

ARTHRITIS Joint pain. A diagnosis of arthritis means that you are experiencing joint inflammation that causes pain, swelling, stiffness, and redness in any joint in the body. Note: Unlike arthritis, fibromyalgia is not an inflammatory illness, nor does it cause degeneration of joint or connective tissues (for example cartilage).

AUTONOMIC NERVOUS SYSTEM A part of the vertebrate nervous system that innervates smooth and cardiac muscle and glandular tissues and governs involuntary actions (as secretion, blood vessel functions, intestinal and esophagus performance, etc.) and consists of the sympathetic nervous system and the parasympathetic nervous system.


BARTHEL INDEX This index measures the extent to which somebody functions independently (in their activities of daily living such as bathing, walking and dressing) and has mobility. It also indicates the need for care. The Barthel Index contains 15 items. Each item is assessed by four scores: function intact (1), function limited (2), assistance is needed (3), and function impossible (4). The Barthel ADL Index was first developed by Mahoney and Barthel in 1965 and later modified by Collin et al in 1988.

BASELINE The initial assessment at the start of a study. The effect of an intervention (e.g. a new tablet) can be determined by comparing baseline scores to follow up scores.

BASIC SCIENTIFIC RESEARCH This term is usually used to differentiate studies involving real live patients (e.g. a trial of a new type of physiotherapy, clinical research) from work based in a test tube in a laboratory (basic scientific research). In rheumatology we need both.

BASDAI Bath Ankylosing Spondylitis Disease Activity Index: Measures AS-specific disease activity. Range 0-10; higher values indicating higher disease activity.

BIAS Something that distorts a process. This process could be a meeting where a person’s views may be biased, favoring only one way of looking at things, or the process of some research itself where results are distorted, for example by only including patients who can go to the hospital; some studies are biased and the results cannot be generalized to patients who are less mobile and cannot therefore get to the hospital as outpatients.

BIOFEEDBACK The technique of making unconscious or involuntary bodily processes (as heartbeat or brain waves) perceptible to the senses (as by the use of an oscilloscope) in order to manipulate them by conscious mental control.

BIOMEDICAL RESEARCH Scientific research that relates and applies to clinical medicine.

BLINDED TRIAL The principle that if you don’t know what treatment you are on (maybe you get a placebo), you can’t influence the results. Single blind means that only the patient doesn’t know whether he or she gets the real drug or a placebo. Double blind means that neither the patient nor the clinician (doctor, nurse, or researcher) knows.


CAM Complementary and alternative medicine.

CASE STUDY Research based on one or a few patients. Case studies may be very detailed and are a good way of finding out about rare conditions or illnesses. Case studies are usually retrospective (looking back at events), not prospective (or looking forwards to events as they happen) and so are not very useful for coming to conclusions about the safety or efficacy of different treatments.

CENTRAL NERVOUS SYSTEM The part of the human nervous system which consists of the brain and spinal cord, to which sensory impulses are transmitted and from which motor impulses pass out, and which supervises and coordinates the activity of the entire nervous system.

CERVICAL SPINAL STENOSIS A narrowing of the cervical (C-1 through C-7) spinal canal.

CHRONIC Describes a disease or condition that persists throughout a person’s life and must be managed because it cannot be cured. Chronic illness is characterized by alterations in normal functioning that cannot be reversed or stopped by current medical knowledge. However, most chronic illnesses can be effectively managed using medical treatment combined with patient education. Knowledge regarding the cause of an illness and changes in behavior (for example, coping skills) may reduce symptoms and can help produce a better quality of life.

CIRCADIAN RHYTHM The daily rhythm that you body adjusts to in order to carry out essential biological functions.

CLINICALLY RELEVANT A principle, fact, or study that is directly applicable to patient care.

CLINICAL TRIAL see also: Case Study, Cohort Study, Randomized Clinical Trial (RCT) cf. Basic Scientific Research. Usually applied to studies that have direct applicability to patients and their care, or are carried out in patients, rather than in a laboratory.

CLINIMETRY The science of clinical measurement.

COGNITIVE Of, relating to, or being conscious of intellectual activity (as thinking, reasoning, remembering, imagining, or learning words).

COGNITIVE BEHAVIOR THERAPY (CBT) Psychotherapy that is concerned with the treatment (as by desensitization or aversion therapy) of observable behaviors rather than underlying psychological processes. It applies principles to substitute desirable responses and behavior patterns for undesirable ones (as phobias or obsessions). Called also “behavior therapy.”

COHORT STUDY A research method concerned with observing events involving a particular group of people over time (such as a group of patients’ progress in long-term treatment) in order to provide information, which is useful for identifying longer-term strategies and treatments that are effective.

COMORBIDITY The existence of two chronic diseases in one person at the same time; for example, a patient with the joint disease rheumatoid arthritis and the skin disease psoriasis.

COMPLIANCE (Same as Adherence) How well the patient complies with an agreed treatment plan.

CONCOMITANT (therapies) Other treatments used at the same time as the treatment under investigation. They may be for the same condition or for unrelated conditions.

CONNECTIVE TISSUE Joints, bones, cartilage, and other tissue that supports and holds together different parts of the body.

CONTROL GROUP see: controlled study

CONTROLLED STUDY Early in the development of clinical research it became clear that it can be very difficult to disentangle the real effect of an intervention or treatment from the natural background variation in the way patients feel. In other words, patients may feel better or worse and it has nothing to do with the study treatment. To address this problem, study designers often observe patients or volunteers who have not been given the active treatment, and compare their progress with those that have. The former group is termed a control group, and such a study a controlled study. To minimise bias such studies are often randomized (there is an equal chance of any individual being allocated to either the active or the control group) and (double or single blind) placebo controlled.

COPING STRATEGIES (PASSIVE COPING) The way that people react to radical events (life-strains of stressors). People who have a chronic disease have to deal with the pain and stresses of their disease, e.g. uncertainties about the future, problems at work and in daily life, etc. When people experience an event as stressful, they begin to make efforts to cope with that event. Coping is the process of attempting to manage demands that are seen as taxing or exceeding one’s resources. People can use various coping strategies. Two general types of coping strategies can be distinguished: strategies aimed at solving problems (problem-focused coping) and strategies aimed at controlling emotional reactions to a stressful event. Examples of problem-focused strategies people can use are problem-solving or information seeking. Emotion-focused strategies are, for instance, seeking emotional support, venting feelings, avoidance, and denial. Coping strategies are of great importance in relation to the extent of the negative influence the disease has on the patient. Research has shown that people who react in an active way to the consequences of their disease, are more effective than people who react in a passive way.

COPM The Canadian Occupational Performance Measure (COPM) is an outcome measure designed for use by occupational therapists to assess client outcomes in the areas of self-care, productivity and leisure. It is a measure of a client's self-perception of occupational performance in these areas. The COPM is administered using a semi-structured interview in which the client identifies significant issues in daily activities which are causing difficulty. Two scores, for performance and satisfaction with performance, are obtained. (Law M, Baptiste S, McColl M, Opzoomer A, Polatajko H, Pollock N. The Canadian occupational performance measure: an outcome measure for occupational therapy.

CORTICOSTEROID A medication used for relief of inflammation and pain, sometimes called steroids.

CROSS-SECTIONAL A cross-sectional study is an observational study, in which the observations (e.g. responses to a questionnaire) are made on a single occasion. Cross-sectional studies generally focus on a single group of people representative of the population of interest. Cross-sectional studies can be a useful way of getting a lot of information quickly but are not considered as powerful as prospective (or longitudinal) studies, in which patients or a disease process are/is followed over time.

CYTOKINES Cytokines are immune system cells (found in synovial fluid) that have been linked to the rheumatoid arthritis disease process of inflammation and cartilage destruction.


DELPHI METHOD The Delphi Process is a means of reaching consensus through structured consultation between a group of people who may have very different perspectives and fields of expertise. It is particularly useful where there is little or no published information on the subject under consideration. Unlike more familiar consultation methods such as steering groups, the Delphi Process doesn’t need participants to physically meet together, and there is no limit on how many people can be involved. Since the process is anonymous, it avoids “power struggles” because there is no opportunity for a strong individual to unduly influence the group and people can change their minds without losing face. The process also enables a combination of many opinions into a group response and can be completed in as short a time as possible. To ensure anonymity, the Delphi Process uses questionnaires. These involve a number of statements to which participants respond using a ranking system. Reponses are analysed centrally and then fed back to all participants, enabling individuals to change their mind and re-rank their answers if they wish, in light of opinions expressed by the group. The process is repeated until consensus is reached. At the end, a statistical response is arrived at for each statement that equates to the strength of opinion felt by the group. The result can then be used as a benchmark for developing good practice.

DEPRESSION Depression is a disorder of mood, characterized by sadness and loss of interest in usually satisfying activities, a negative view of the self, and hopelessness, passivity, indecisiveness, suicidal intentions, loss of appetite, weight loss, sleep disturbances, and other physical symptoms.

DISEASE A condition that affects an organism and impairs its normal physiological functioning. Sometimes this term is only used for conditions where there is structural or functional change in the organs or tissues involved.

DISORDER A disruption of regular or normal functions of health.

DOMAIN Broad area of measurement (e.g. physical function).

DOPAMINE A monoamine, C8H11NO2, that is a decarboxylated form of dopa and occurs especially as a neurotransmitter in the brain and as an intermediate in the biosynthesis of epinephrine.

DOUBLE BLIND see: Blinded Trial

DRP Carr’s Disease Repercussion Profile is an individualized measure that gives a profile of perceived impairment in 6 domains: functional activities, social activities, socio-economic status, relationships, emotional well-being, and body image. Patients specify the impairment they are experiencing in each of the domains and rate its severity on a 10-point graphic rating scale. The instrument is designed to help choose an intervention to suit patients rather than to assess outcomes of chosen interventions in groups of patients.


EFFECTIVENESS The extent to which something actually works. In medicine this is a precise term and relates to the effect size (see below). Effectiveness of a specific treatment may be estimated from relevant research literature but many trials do not include patients with co-morbidity (there might be multiple exclusion criteria), and so the effect size may be less in a typical clinical setting.

EFFECT SIZE SES (Standardized Effect Size). A simple way to determine the degree of improvement (or otherwise) of a particular therapy after any placebo effect has been accounted for. The effect size is calculated as the ratio of the treatment effect (mean differences in treatment group minus differences in placebo group) to the pooled standard deviation of these differences.

EFFICACY The extent to which a treatment improves outcomes under ideal circumstances, for example the maximum effect in patients who didn’t experience side effects and took all prescribed drugs.

EFFICIENCY A statistical measure. The mean (average) change in the measure divided by the standard deviation (a statistical measure of spread) of the change.

EMPIRICAL A treatment derived from experiment and observation rather than theory. In practice this term applies to treatments based upon the individual’s clinician’s experience and judgement.

EMPOWERMENT Making it possible for people who are disempowered to exercise power and have more control over their lives. That means having a greater voice in institutions, agencies, and situations that affect them.

ENZYME A protein that accelerates chemical reactions.

EULAR The first European League Against Rheumatism congress took place in 1947. At that time there were 11 members. The congress was held every four years. Each year the Eular organized a symposium. Because of the increasing number of members (42 countries in 2000) Eular has organized a conference each year since 2000. There are scientific programs and programs for allied health professionals and for patient organisations.

EUROQol The EUROQol is a short self-report questionnaire to measure generic health-related quality of life in 5 dimensions: mobility, self-care, usual activity, pain/discomfort, and anxiety/depression. Each dimension is measured with one item and scored between 0 to 1 (0 equals death and 1 perfect health). It also includes a 0-100 graphic rating scale to measure overall health status. The EuroQol (EQ-5D) was developed by the EuroQol Group in 1990.

EVIDENCE BASED MEDICINE Evidence-Based Medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence-based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research. By individual clinical expertise we mean the proficiency and judgement that individual clinicians acquire through clinical experience and clinical practice. By best available external clinical evidence we mean clinically relevant research, often from the basic sciences of medicine, but especially from patient-centred clinical research into the accuracy and precision of diagnostic tests (including the clinical examination), the power of prognostic markers, and the efficacy and safety of therapeutic, rehabilitative, and preventive regimens. External clinical evidence both invalidates previously accepted diagnostic tests and treatments and replaces them with new ones that are more powerful, more accurate, more efficacious, and safer.

There are 4 levels of evidence which are broadly recognized:

1.  Meta-study 2.  Controlled trials (RCT’s) 3.  Observational study 4.  Expert opinions

EXCLUSION CRITERIA Pre-defined factors that exclude a subject from a trial. For example: clinical studies often exclude patients that would be unable to attend for review for any reason. Many studies exclude subjects of less than 18 years old.


FIBRO-FOG Is a commonly reported symptom of fibromyalgia. Fibromyalgia patients often describe multiple sensations of fatigue and listlessness combined with transitory states of confusion, poor attention and concentration, and short-term memory loss. This fibro fog tends to exacerbate the deficits in daily functioning that a fibromyalgia sufferer must deal with.

FIBROMYALGIA DIAGNOSTIC CRITERIA The American College of Rheumatology 1990 Criteria for the Classification of Fibromyalgia History of widespread pain has been present for at least three months

Definition: Pain is considered widespread when all of the following are present:

1.  Pain in both sides of the body 2.  Pain above and below the waist. In addition, axial skeletal pain (cervical spine, anterior chest, thoracic spine or low back pain) must be present. Low back pain is considered lower segment pain.

Pain in 11 of 18 tender point sites on digital palpation

Definition: Pain, on digital palpation, must be present in at least 11 of the following 18 tender point sites:

1.  Occiput (2) - at the suboccipital muscle insertions. 2.  Low cervical (2) - at the anterior aspects of the intertransverse spaces at C5-C7. 3.  Trapezius (2) - at the midpoint of the upper border. 4.  Supraspinatus (2) - at origins, above the scapula spine near the medial border. 5.  Second rib (2) - upper lateral to the second costochondral junction. 6.  Lateral epicondyle (2) - 2 cm distal to the epicondyles. 7.  Gluteal (2) - in upper outer quadrants of buttocks in anterior fold of muscle. 8.  Greater trochanter (2) - posterior to the trochanteric prominence. 9.  Knee (2) - at the medial fat pad proximal to the joint line.

Digital palpation should be performed with an approximate force of 4 kg. A tender point has to be painful at palpation, not just tender.

FIQ The Fibromyalgia Impact Questionnaire (FIQ) is an instrument designed to quantitate the overall impact of fibromyalgia over many dimensions (e.g. function, pain level, fatigue, sleep disturbance, psychological distress etc.). It is scored from 0 to 100 with 100 being the worst case. The average score for patients seen in tertiary care settings is about 50. The FIQ is widely used to assess change in fibromyalgia status and has been translated into several languages.

FLARE A period of time (with a start and a finish) when symptoms recur, becoming worse and then slowly starting to improve again. A flare does not mean that fibromyalgia symptoms are getting worse.

FOCUS GROUP A research method of gathering information from people while they are discussing a subject in small groups.

FSS The Fatigue Severity Scale.

fMRI or FUNCTIONAL MRI Magnetic resonance imaging used to demonstrate correlations between physical changes (as in blood flow) in the brain and mental functioning (as in performing cognitive tasks).


GHQ The General Health Questionnaire is a 12-item instrument and has been tested for reliability, validity, and sensitivity as a screening tool for mental disorder and as a measure of short-term psychological distress. Subjects score between 0 and 12, with high scores indicating high levels of distress.

GENERAL SELF-EFFICACY SCALE The GSES is a general measure for self-efficacy. Whilst it is not disease-specific, it is used for rheumatoid arthritis.

GENETIC PREDISPOSITION The genetic susceptibility to inherit a specific characteristic of disease.

GROWTH HORMONE A vertebrate polypeptide hormone that is secreted by the anterior lobe of the pituitary gland and regulates growth; used to treat children with growth hormone deficiencies and by athletes to increase muscle mass.


HAD Hospital Anxiety Depression Scale. The Hospital Anxiety and Depression Scale was developed in 1983 by Zigmond and Snaith for people with physical health problems.  It differs from many other measures of anxiety and depression in that it does not contain questions about physical symptoms. Many other measures include questions about symptoms such as aches and pains, loss of appetite, or inability to sleep, and treat these as indicators of depression or anxiety. Clearly this would not be appropriate for people with, say, arthritis, where their aches and pains and inability to sleep are more likely due to their physical illness rather than an indicator of depression.

HAWTHORNE EFFECT This is based on a series of studies on the productivity of workers at factory which manipulated various conditions (e.g. pay, light levels, heating, rest breaks);each change resulted on average over time in productivity rising, including eventually a return to the original conditions. This was true of each of the individual workers as well as the group mean. Clearly the variables the experimenters manipulated were not the only nor dominant causes of productivity. One interpretation was that the important effect here was the feeling of being studied. It is this that is now referred to by “the Hawthorne effect.”

HAQ Stanford Health Assessment Questionnaire - The HAQ was developed in 1980 by Fries et al. It is a measure of functional ability and is based on the belief that a patient desires to be alive, free of pain, functioning normally, experiencing minimal treatment toxicity, and financially solvent. The measurements are on a scale of 0 (best) to 3 (worst). It is a self-administered measure that evaluates four dimensions: disability, discomfort, drug side effects, and costs. The disability section of the HAQ contains 20 questions about difficulties experienced with eight categories of activities of daily living, and four questions about the assistance used to perform these activities. The Modified HAQ, which contains only eight of these questions, one from each category, is commonly used.

HRQoL The Health Related Quality of life "QoL” can be thought of as the overall impact of the illness and its treatment on patients physical,psychological and social functioning.

HOLISTIC Relating to or concerned with wholes or with complete systems rather than with the analysis of, treatment of, or dissection into parts; holistic medicine attempts to treat both the mind and the body.

HORMONES Chemical messengers that include insulin, estrogen, thyroid, steroids, progesterone, and testosterone, which are all  products of living cells. They circulate in body fluids (as blood) or sap and produce a specific, often stimulatory effect on the activity of cells usually remote from its point of origin.

HYPERMOBILITY (JOINT) An increase in the range of movement of which a bodily part and especially a joint is capable; the term “double jointed” is derived from this abnormality.

HYPOTHESIS A proposed mechanism that might explain a known fact or observation. A hypothesis may be tested by a well-designed research protocol. Unlike a theory it is not supported by direct evidence; rather it is the question we are asking in our research study.


ICER Incremental Cost Effectiveness Ratio - Where effectiveness is measured in Quality Adjusted Life Years (see: QALYs), the Incremental Cost Effectiveness Ratio compares the cost per Quality Adjusted Life Year of two competing interventions in terms of a ratio. Thus if intervention 1 costs $32,000 per Quality Adjusted Life Year and intervention 2 costs $16,000 per QALY, the Incremental Cost Effectiveness Ratio is 32 000/16 000 = 2. In order that fair, reasonable and justifiable decisions can be made when comparing treatments, the effects of treatments as well as the costs have to be considered. Often the way of doing this is to calculate an Incremental Cost Effectiveness Ratio. Usually a new treatment is compared with a current treatment and the ICER is calculated as the difference in the cost of the treatments (the new minus the current treatment) divided by the difference in effectiveness of the treatments (the new minus the current).

When effectiveness is measured in Quality Adjusted Life Years the Incremental Cost Effectiveness Ratio answer is in cost per QALY gained ($ per QALY). For example, if a new treatment costs $30,000 more than the current treatment but results in 3 extra Quality Adjusted Life Years then the ICER is $30,000/3 = $10 000 per QALY. By comparing ICER values (in $ per QALY) for many new treatments versus the current treatments (even treatments for a number of different diseases) the decision-makers can be helped in figuring out which competing new treatments are worth adopting. When two treatments are equal in effectiveness, the ICER cannot be calculated. Instead a cost minimization analysis is done, which merely means the cheaper of the two treatments is identified and the cost difference quantified.

IMMUNE SYSTEM The bodily system that protects the body from foreign substances, cells, and tissues by producing the immune response; it includes especially the thymus, spleen, lymph nodes, special deposits of lymphoid tissue (as in the gastrointestinal tract and bone marrow), lymphocytes including the B cells and T cells, and antibodies.

IL-1 INTERLEUKIN One of the pro-inflammatory cytokines in the immune system thought to play a role in the disease process of rheumatoid arthritis, including bone erosion; the IL-1 receptor is the target of a new biological response modifier, Anakinra.

INCLUSION CRITERIA The predefined characteristics that allow a subject to be entered for consideration for a trial. In a study of osteoarthritis, inclusion criteria might be determined as pain on most days of one month and definite radiographic evidence of osteoarthritis of the affected joint.

INFLAMMATION The body’s response to tissue injury or foreign substances that usually produce symptoms of heat, swelling, redness, and pain.

INFORMED CONSENT The decision by a person to give or not give permission for an action affecting them. The decision is based upon having all the information bearing on the situation including the advantages, disadvantages, and the various consequences involved.

INTERSTITIAL CYSTITIS A chronic idiopathic cystitis (inflammation of the urinary bladder) characterized by painful inflammation of the subepithelial connective tissue and often accompanied by Hunner’s ulcer.


JPBA Joint Protection Behaviour Assessment was constructed by Hammond and associates to determine the effect of protection methods during everyday activities on the patient’s behavior. It is not a questionnaire but an observational method (video-recorded and evaluated).

KRUPP SCALE The Krupp Fatigue Severity Scale includes 9 items rated on 7-point scales and is sensitive to different aspects and gradations of fatigue severity. Most items in the Krupp scale are related to behavioral consequences of fatigue.


LDAS Low Disease Activity State

LIKERT SCALE The Likert Scale is a type of attitudinal rating scale which asks people to show the extent to which they agree or disagree with statements. There are five to seven possible response choices. The most common scale is 1 to 5. Often the scale will be 1=strongly disagree, 2=disagree, 3=not sure, 4=agree, and 5=strongly agree. The result is obtained by calculating the average (i.e. mean) of all the results added together. Likert scales are often used in questionnaires to measure attitudes.

LONGITUDINAL Measurements made repeatedly over a long period of time.


MAF INDEX The Multidimensional Assessment of Fatigue (MAF) scale contains 16 items and measures four dimensions of fatigue: severity (#1-2), distress (#3), degree of interference in activities of daily living (#4-14), and timing (#15-16). Fourteen items contain numerical rating scales (#1-14) and two items have multiple-choice responses (#15-16). Respondents are asked to reflect on fatigue patterns for the past week. The MAF is a revision of the Piper Fatigue Scale, a 41-item measure of fatigue developed for research purposes and tested with oncology patients.

MAGNETIC RESONANCE IMAGING (MRI) A noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within the body induced by the application of radio waves.

McCOY SEXUAL RATING SCALE This scale covers sexual experience and responsiveness during the past 30 days. This instrument contains 10 items on a seven point scale relating to different aspects of sexual life, such as frequency of intercourse, orgasm frequency, sexual pleasure and satisfaction, lubrication, dyspareunia, arousal, sexual fantasies, and satisfaction with partner.

METABOLISM The body’s ongoing physical and chemical processes, which build up body tissue while eating food and break down while exerting energy. The sum of the processes in the buildup and destruction of protoplasm; specifically, the chemical changes in living cells by which energy is provided for vital processes and activities and new material is used.

MHAQ Modified HAQ see: HAQ

MHIQ McMaster Health Index Questionnaire A standard-item questionnaire on physical, social and emotional function.

MSS The Modified Sharp Score is a measure of joint damage as assessed radiographically, and is based on joint space narrowing and erosions. The MSS is developed by Van der Heijde, based on the original assessment method of Sharp.

MEDLINE-REVIEW National Library of Medicine’s premier bibliographic database. It contains 9 million records of bibliographic citations and author abstracts from approximately 3.900 current biomedical journals.

META-ANALYSIS The process of combining the data from a number of independent studies (usually drawn from the published literature) and synthesizing summaries and conclusions addressing a particular issue. It aims to utilize the increased power of pooled data to clarify the state of knowledge on that issue. Meta-analysis is often used in systematic reviews of effect studies of medical therapies to evaluate therapeutic effectiveness. The Cochrane Reviews are meta-analyses.

MINIMAL CLINICALLY IMPORTANT DIFFERENCE A minimal clinically important (or relevant) difference (MCID) can be defined as the smallest difference in score on an outcome measure (e.g. pain, disability, quality of life), which patients perceive as beneficial. This MCID can be used as a criterion to assess if a therapy has potential beneficial effects.

MULTI-DISCIPLINARY A team that includes a patient and all of the health professionals involved in the patient’s care.

MYOFASCIAL PAIN SYNDROME Muscle pain similar to fibromyalgia pain, but located in only one area or region of the body.

MYELOPATHY Any disease or disorder of the spinal cord or bone marrow, including stenosis, a narrowing of the cervical or lumbar spinal canal.


NATUROPATHIC A system of treatment of disease that avoids drugs and surgery and emphasizes the use of natural agents (as air, water, and herbs) and physical means (as tissue manipulation and electrotherapy).

NEURALGIA A painful condition caused by disorders of the nervous system.

NEUROENDOCRINE SYSTEM A complex system of brain structures and glands that help regulate the release of a large number of hormones, steroids, and neuropeptides that contribute to the transmission and inhibition of pain. The neuroendocrine system interacts with the sympathetic and parasympathetic nervous systems as well as the immune system, and thus plays an important role in other dimensions of health and illness such as sleep regulation, fatigue, and responses to stressful events.

NEUROPATHY Alterations in the function of nerves that are produced by disease or injury. These alterations in function might produce symptoms such as increased sensitivity with numbness or tingling, pain and burning, decreased sensation, or muscle weakness.

NEUROTRANSMITTER A substance (as norepinephrine or acetylcholine) that transmits nerve impulses across a synapse.

NEUROPEPTIDE An endogenous peptide (as an endorphin or an enkephalin) that influences neural activity or functioning.

NEURALLY MEDIATED HYPOTENSION Neurally mediated hypotension is also known by the following names: the fainting reflex, neurocardiogenic syncope, vasodepressor syncope, the vaso-vagal reflex, and autonomic dysfunction. Hypotension is the formal medical term for low blood pressure, and syncope is the term for fainting. Neurally mediated hypotension occurs when there is an abnormal reflex interaction between the heart and the brain, both of which usually are structurally normal.

NOREPINEPHRINE A neurotransmitter that is produced in the adrenal gland that activates the autonomic nervous system.

NSAID Abbreviation for Non-Steroidal Anti-Inflammatory Drugs that help relieve pain and swelling. They include aspirin, ibuprofen, and Cox-2 inhibitors, and are used to reduce inflammation and pain associated with illnesses, including, rheumatoid arthritis, osteoarthritis, and lupus. Although fibromyalgia is not an inflammatory disease, NSAIDs are sometimes prescribed for people with this condition because they may alter pain transmission in the spinal cord or other parts of the central nervous system. The response to NSAIDs tends to vary greatly among people with fibromyalgia.


OMERACT Outcome Measures in Rheumatology - coined at the first conference held in Maastricht, the Netherlands, in 1992, an acronym for Outcome MEasures in Rheumatoid Arthritis Clinical Trials. Since then, the Omeract initiative has turned into an international informal network, working groups, and gatherings interested in outcome measurement across the spectrum of rheumatology intervention studies. Omeract strives to improve outcome measurement through a data driven, iterative consensus process.

OUTCOME The effect of treatment on a patient, which may be measured in a number of ways. Objective measures (outcomes) are independent of the opinion of the patient, e.g. radiologic joint damage (X-rays), biological blood tests (rheum factor, serum levels of MMPs, ECR and CRP). More subjective outcomes are based on the experience or opinion by the patient, e.g. questionnaires like HAQ. Outcome expectancy is a belief that certain behaviour will lead to a certain outcome (e.g. pacing one’s lifestyle will lead to reduced fatigue).

OVERLAPPING CONDITION A secondary illness that accompanies the primary illness affecting an individual. People with fibromyalgia are often affected by one or more overlapping illnesses such as irritable bowel syndrome, chronic tension-type headaches, restless legs syndrome, or interstitial cystitis.


PARADIGM A way of thinking about a particular problem or issue.

PASI In the Patient Specific Index, patients are asked to rate 21 complaints for severity and importance plus any additional complaints. Both severity and importance are rated on a 7 category ordinal rating scale. The score on the PASI includes only those items that the patient identifies as problems and is the sum of the products of severity and importance for each item. Since the number of problems can vary from patient to patient, scores are standardized by dividing by the maximum possible score for that patient and multiplying by 100.

PEER REVIEW Research proposals and results are usually reviewed by a number of independent people who nevertheless have an interest in research, so that data, information and methods can be verified from a range of perspectives. Consumers often act as peer reviewers. They may not feel able to comment on the research method, but will have very valuable views about whether the research topic is an important one for consumers, and whether the research involves consumers in an appropriate way.

PEPTIDE Any of various amides that are derived from two or more amino acids by combination of the amino group of one acid with the carboxyl group of another and are usually obtained by partial hydrolysis of proteins.

PERIPHERAL NERVOUS SYSTEM The part of the nervous system that is outside the central nervous system (brain and spinal cord) and comprises the cranial nerves except the optic nerve, the spinal nerves, and the autonomic nervous system.

PET Problem Elicitation Technique is a modified version of the MACTAR and allows patients to assess their ability to perform the daily physical activities most important to them. Patients continue to identify and rank their problems but are asked to rate on a VAS scale the degree of difficulty, frequency, or severity of the problem, depending on its type. Patients are also asked to rate the importance of each item on a VAS scale, and these values are used as weights. A VAS global health assessment is the final question.

PGWB Psychological General Well-Being Index is a self-assessed inventory related to general well-being and has been shown to be reliable and valid. The PGWB comprises 22 items with a six-point response scale. The factors of anxiety, depressed mood, positive well being, self control, general health, and vitality are related to the total score. The subscales of these measured factors have three to five items. For each item, there are six response options that are rated on a scale of 1 to 6, according to the intensity or frequency of the affective experience. A value of 1 is given for the most negative options and 6 for the most positive options. The score range for the PGWB is 22-132; a higher score represents better well-being.

PLACEBO A sham treatment. If the treatment is a tablet or capsule it will contain no active ingredient. The best placebos are identical to the real drug and help to maintain blinding in either single or double blind trials. Placebos are used to help separate the real effect of the active ingredient from any benefit (or side effects) that the subject may experience by chance or purely by the acting of taking tablets.

PROSPECTIVE STUDY A study where patients are selected before any data collection starts.

PROTOCOL The plan or set of steps to be followed in a study. A protocol for a systematic review, for example, should describe the rationale for the review, the objectives, and the methods that will be used to locate, select, and critically appraise studies, and to collect and analyse data from the included studies.


QALYs A Quality Adjusted Life Year is a measure that incorporates both health status and length of life into a single measure. A Quality Adjusted Life Year of 0 is death and 1 is one year of full health. It is used as the measurement of effectiveness of interventions.

It is a useful measure of treatment effects because it allows comparisons between treatments for different diseases. For example, one treatment for people with rheumatoid arthritis might increase joint mobility by 50% and reduce constant severe pain to mild pain occasionally, while another treatment for people with epilepsy might reduce seizure frequency from 80 per week to only 10 per week; how can we compare these? If the effects of both treatments are translated into health-related quality of life measures (e.g. as QALYs), then they can be compared.

QUALITATIVE RESEARCH Research that gathers information, which is varied, in-depth and rich. The information sought is about how something is experienced and not specifically about facts and figures. Information from qualitative research is often more difficult to interpret, partly because it cannot be measured. The emphasis is on the quality and depth of information. These data might be collected in the form of in-depth interviews with patients. The interviews are taped and the transcripts are systematically analysed to see what ideas emerge.

QUANTITATIVE RESEARCH Deals with facts, figures, and measurements, and produces data which can be readily analyzed. Measurable data is gathered from a wide range of sources, and it is the analysis and interpretation of the relationships across this data that gives the information researchers are looking for. These data are collected using numbers, perhaps through answers to questionnaires. The numbers are then examined using statistical tests to see if the results have happened by chance.


RAND-36 A general (not disease specific) questionnaire to measure quality of life.

RANDOMIZED CONTROLLED TRIAL (RCT) (Synonym: randomized clinical trial) - An experiment in which investigators randomly allocate eligible people into (e.g. treatment and control) groups to receive or not to receive one or more interventions that are being compared. The results are assessed by comparing outcomes in the treatment and control groups.

RAYNAUD’S PHENOMENON When blood is restricted from reaching the fingers and toes in response to cold. The skin turns pale and begins to tingle, becomes numb, and turns painful.

RESPONSIVENESS The ability of an instrument (methods, questionnaire etc.) to measure a significant change in disease-activity over time. The ACR and the Eular recommend different response criteria (or improvement criteria).

RESTLESS LEGS SYNDROME A neurological disorder characterized by unpleasant sensations in the legs and an uncontrollable urge to move when at rest in an effort to relieve these feelings. RLS sensations are often described by people as burning, creeping, tugging, or like insects crawling inside the legs. Often called paresthesias (abnormal sensations) or dysesthesias (unpleasant abnormal sensations), the sensations range in severity from uncomfortable to irritating to painful.

RETROSPECTIVE STUDY A study where patients are selected then their medical records are used to find out what has happened to them.

RITCHIE INDEX A scoring system for recording joint tenderness.


SEIQoL The Schedule for the Evaluation of Individual Quality of Life was developed by O’Boyle et al. and first published in 1991. It asks patients to list the 5 areas of life that they judge to be most important to their overall quality of life, which they then rate on a VAS. Areas can be, for example, family, work, leisure activities, religion and health. The SEIQoL is not a disease specific but a general measure instrument. There are two versions: the original judgement analysis method (-JA) and, since 1996, a quicker version called the direct weighting method (-DW).

SELF-EFFICACY A belief that you could do something if you wanted to, for example, a belief that you could manage, or help to alleviate your pain by using a hot/cold compress. A high self-efficacy for a task may mean that you are more likely to try it out.

SELF MANAGEMENT As a constant process of behavioral choices and decision-making that can be achieved by changing knowledge, skills, and attitudes, and initiating behaviour change.

SENSITIVITY the extent to which a test gives ‘abnormal’ outcomes in ill people. A sensitive test gives only a few ‘false-negative’ outcomes.

SEROTONIN A phenolic amine neurotransmitter that is a powerful vasoconstrictor and is found especially in the brain, blood serum, and gastric mucous membrane of mammals; called also 5-HT, 5-hydroxytryptamine.

SF36 The Medical Outcome Study Short Form 36 measures three major health attributes (functional status, wellbeing, overall health) in eight subscales. These include PF (Physical function), RP (role limitations due to physical health), BP (bodily pain), GH (general health), VT (vitality), SF (social function), RE (role limitations due to emotional health), and MH (mental health). For each variable item, scores are coded, summed, and transformed to a scale from 0 (the worst possible health state) to 100 (the best possible health state).

SIGNIFICANT What is a significant difference (improvement or change in disease activity)? It is important to know how many patients actually improved. In research, statistical tests will show whether a result arose by chance, or whether it is unlikely to have happened by chance and can therefore be said to be significant (e.g., a statistically significant change in pain on a new drug).

SJOGREN’S SYNDROME A chronic inflammatory autoimmune disease that affects especially older women, characterized by dryness of mucous membranes especially of the eyes and mouth and by infiltration of the affected tissues by lymphocytes, and that is often associated with rheumatoid arthritis and may co-exist with fibromyalgia.

SLEEP The natural periodic suspension of consciousness during which the powers of the body are restored.

APNEA Sleep apnea is caused by recurring interruption of breathing during sleep because of obstruction of the upper airway by weak or malformed pharyngeal tissues that results in hypoxemia and in chronic lethargy during the day; called also obstructive sleep apnea syndrome.

REM SLEEP A state of sleep that recurs cyclically several times during a normal period of sleep and is characterized by increased neuronal activity of the forebrain and midbrain, by depressed muscle tone, and especially in humans by dreaming, rapid eye movements, and vascular congestion of the sex organs; called also desynchronized sleep, paradoxical sleep, rapid eye movement sleep.

Characteristics of REM State:

1.  EEG brain waves are small and irregular, with big bursts of eye activity. The brain wave activity at this time resembles waking more than it does sleeping. 2.  The four non-REM phases are characterized by progressive relaxation. But during REM phase, the body’s activity perks up considerably. 3.  Blood pressure may increase drastically. 4.  Pulse rates increase in an irregular way. 5.  The sleeper with cardiac problems faces the greatest risk of heart attack at this time. 6.  Breathing becomes irregular and oxygen consumption increases. 7.  The chin is slack during REM sleep. 8.  The face, toes and fingers may twitch. 9.  A man experiences penile erections; a woman experiences clitoral engorgement. 10.  Sleepers’ large muscles are literally paralyzed. They cannot move their torsos, arms or legs. 11.  The body seems to have abandoned its effort to regulate its temperature during the REM phase. 12.  Shivering and sweating cease at this time, and the body’s temperature drifts gradually toward the temperature of its environment.

The first REM period is usually brief. After this, the sleeper may wake up briefly. This is quite normal. A good sleeper may not remember it the next day. A poor sleeper, however, may wake up at this point and have difficulty getting back to sleep.

SLOW WAVE SLEEP: A state of deep usually dreamless sleep that occurs regularly during a normal period of sleep with intervening periods of REM sleep and that is characterized by delta waves and a low level of autonomic physiological activity; called also non-REM sleep, NREM sleep, orthodox sleep, S sleep, synchronized sleep.

STAGE 1 SLEEP is the period we "drift off."

Stage 1 Non-REM Sleep is characterized by the following:

1.  Breathing becomes slow and even 2.  The heartbeat becomes regular 3.  Blood pressure falls 4.  Brain temperature decreases 5.  Blood flow to the brain is reduced 6.  Little or no body movement

Generally, this description of bodily functions characterizes all non-REM sleep.

Stage 1 sleep might be called a kind of twilight time. Its initial appearance lasts up to ten minutes in most sleepers. Brain waves become smaller, slower, and somewhat irregular characterized by a low-voltage fast EEG. This portion of sleep is distinguished by drifting thoughts and dreams that move from the real to the fantastic, along with a kind of floating feeling. The sleeper is still easily awakened and might even deny having slept.

STAGE 2 SLEEP Non-REM - Stage 2 is an intermediate stage of sleep. It initially lasts about twenty minutes. The sleeper will gradually descend deeper into sleep, becoming more and more detached from the outside world and progressively more difficult to awaken.

Stage 2 Non-REM Sleep is characterized by:

1.  Larger brain waves and occasional quick bursts of activity. 2.  The sleeper will not see anything even if the eyes are opened. 3.  A sleeper can easily be awakened by sounds. 4.  Bodily functions slow down. Blood pressure, metabolism, secretions, and cardiac activity decrease.

STAGE 3 SLEEP Non-REM Stage 3 is the beginning of deep sleep, occurring about thirty to forty five minutes after you first fall asleep.

Stage 3 Non-REM Sleep is characterized by:

1.  Brain waves are slow (at the rate of 0.5 to 4 per second) and quite large (five times the size of waves in Stage 2). These brain waves are known as delta waves. 2.  The sleeper is far more difficult to awaken as compared to stage 1 or 2 sleep. It takes a louder noise or an active attempt to wake him or her.

STAGE 4 SLEEP Non-REM The deepest sleep occurs in Stage 4.

Stage 4 is characterized by:

1.  The brain waves (called delta brain waves) are quite large, making a slow, jagged pattern on the EEG. 2.  The sleeper experiences virtual oblivion. If the sleeper is a sleepwalker or a bed wetter, those activities will begin this phase. 3.  Bodily functions continue to decline to the deepest possible state of physical rest.

This first period of deep sleep is the deepest. The sleeper awakened from deep sleep will probably be groggy, confused, or disoriented. He or she may experience “sleep inertia” or “sleep drunkenness,” seeming unable to function normally for quite some time.

After the first phase of deep sleep ends, the sleeper returns to Stage 2 and then enters the REM state. This pattern is repeated several times during the night.

SLEEP DISORDER A variety of disorders that are associated with changes in sleep habits (for example, difficulty falling asleep, frequent awakenings from sleep, or reduced quality of sleep or sleep time). These disorders include narcolepsy, insomnia, sleep apnea, restless legs syndrome, and so on. People with fibromyalgia can be affected by any of the dozens of sleep disorders; however, the primary symptom common fibromyalgia is nonrestorative sleep or the absence of feeling refreshed upon waking in the morning.

SOCIAL SUPPORT The interpersonal relations that offer information, emotional relief, material aid and self-reliance. Although assessment scales such as the SS-A (Social Support Appraisals Scale) and SS-B (Social Support Behaviors Scale) have been developed, it is not yet possible to comprehensively measure the main components of the support a person receives from family and friends.

SODA Sequential Occupational Dexterity Assessment This instrument has been developed at Sint Maartenskliniek Research and measures bi-manual functioning of the hands in standardized conditions. The SODA is a valid and reliable instrument to assess objective hand function, or dexterity. It was shown to be sensitive to change in patients with RA over a period of one year. Recently, the manual of the SODA on CD-ROM has been completed to enable occupational therapist to use the test more easily.

SMALLEST DETECTABLE DIFFERENCE (SDD) Smallest detectable differnce that can be seen on an X-Ray. Used as a basis for measuring MCID.

SPECIFITY A classical term in epidemiology, which means the extent to which a test gives normal outcomes in healthy people. A specific test gives only a few false-positive outcomes.

SSRI (Selective Serotonin Reuptake Inhibitor) Any of a class of antidepressants (as fluoxetine or sertraline) that inhibit the inactivation of serotonin by blocking its reuptake by presynaptic nerve cell endings.

SUBSTANCE P A neuropeptide that consists of 11 amino acid residues, which is widely distributed in the brain, spinal cord, and peripheral nervous system, and acts across nerve synapses to produce prolonged postsynaptic excitation.

SYMPTOM A perceptible change in a physical or emotional function (for example, pain, shortness of breath or mood) that reflects an alteration in physiology or health status.

SYNDROME A group of signs and symptoms that occur together and characterize a particular abnormality.

SYSTEMATIC REVIEW A review of a clearly formulated question that uses systematic and explicit methods to identify, select and critically appraise relevant research, and to collect and analyse data from the studies that are included in the review. Statistical methods (meta-analysis) may or may not be used to analyse and summarise the results of the included studies.

SYSTEMIC A systemic condition affects the whole or many parts of the body.


T-CELLS A type of white blood cell which defend the body against disease but sometimes they start attacking the body's own tissue as in rheumatoid arthritis.

TENDER POINTS Areas of muscle or other soft tissues that are extremely sensitive to pressure stimulation. The American College of Rheumatology Fibromyalgia Diagnostic Criteria includes a test in which approximately 4 kilograms of pressure is applied to nine pairs (left side/right side) of tender points. Most health individuals experience pain in only a small number of tender points in response to this test. However, one criterion for fibromyalgia is the experience of pain in 11 of 18 tender points in specific locations of the body during a physical examination.

THALAMUS A mass of nerve cells located deep in the brain, which receives incoming sensory impulses from the spinal cord and then relays them, especially sensory impulses, to and from the cerebral cortex.

TILT TABLE TEST A test that uses an apparatus that rotates a person from a horizontal to a vertical or oblique position. Neurally mediated hypotension cannot be detected with a routine blood pressure or heart rate screening. The diagnosis can be made using a prolonged standing test or more commonly using a tilt table test. Many hospitals and academic centers throughout the world perform tilt table testing. It allows careful measurement of the heart rate and blood pressure responses to the head-up position at a 70-degree angle, in an almost standing position. The usual reason for performing a tilt table test in the past had been for the evaluation of recurrent fainting. Many people with neurally mediated hypotension develop adaptations to keep from fainting, such as crossing their legs, fidgeting, or sitting or lying down when they get lightheaded or tired, but the tilt table test prohibits them from performing those natural defenses. As a result, lightheadedness, nausea, and fainting often occur during the tilt table test. Fatigue and malaise often occur for a few days after the test is performed.

TISSUE A collection of similar cells that act together to perform a specific function of the body.

TREE APPROACH Using a branching algorithm to classify patients into different categories.

TRIGGER POINTS Small areas of muscle that are similar to tender points in that the application of mild pressure produces pain. However, trigger points are characterized by tight bundles of fibers that may refer pain to distant body sites and inhibit contraction or relaxation of the muscle.


UNPROVEN REMEDIES Any treatment that has not been proven safe and effective through repeated scientific studies that have been peer reviewed and published in credible medical journals.

UNWEIGHTED All the information being used is given equal weight or importance.


VALIDITY (external) The extent to which the research findings can be generalized to the wider population of interest and applied to different settings.

VALIDITY (internal) The ability of an instrument (method, questionnaire) to measure what it has to measure (or what we think or expect to measure).

VARIABLE (synonym: factor, outcome) - A variable is a factor you measure, such as pain, depression, disability, CRP. Different variables are measured in different ways, for example:

  • Dichotomous or ‘yes/no’ answers (e.g. alive or dead)
  • Continuous measurements (e.g. length can be 61cm or 61.25 cm or 61.257 cm)
  • Discrete measures have to be whole numbers (e.g. number of children cannot be 1.6!)Categories such as blue or green, no pain or some pain

Variables can also be labeled as:

  • Primary - the main question the study is asking (e.g. change in pain)
  • Secondary the next question you would like to ask (e.g. change in disability)
  • Clinical health status, e.g. pain, disability
  • Demographic details such as age, gender, education level
  • Confounding variables which might confuse your answer (e.g. there seems to be an association between alcohol and lung cancer. But this does not mean alcohol causes lung cancer. The link is really between smoking and lung cancer; alcohol confounds or confuses the issue because people who drink alcohol are more likely to smoke and therefore get lung cancer

VAS Visual Analog Scale A VAS is a way of measuring by asking a person to put a mark on a line, for example a 100 mm. VAS, without scale indication. Only the endpoints are given, for example: no pain at all and extreme pain. In this way you can measure different criteria, like morning stiffness, fatigue or general well being. A VAS can be made by the consultant as well as by the patien

WAX AND WANE Refers to symptoms that come and go without definitive cause.

WEIGHTED The information being used is given different importance depending on the weight assigned to each piece of information.