Biomaterial Database

Disability scales: assessment of reliability. 1986

K Sheikh

Modified or newly developed disability scales have to be assessed for their validity in terms of an appropriate standard and for reproducibility--inter- and intraobserver variability and intrasubject variability. For ordinal scales with more than two points or categories, correlation or regression coefficients are appropriate estimates of validity. An assessment of the sensitivity and specificity of such a scale is not feasible. Indices of proportion agreement or correlation analysis are frequently used to assess the reproducibility of disability scales. These procedures do not, however, correct for chance-expected agreement between two or more sets of observations. In a study of a 31-point ADL (activities of daily living) index used to measure the level of disability in patients with chronic diseases, scores independently rated by two observers were strongly correlated (r = 0.962), yet the two sets of observations were significantly different. An estimate of kappa statistic, that corrects for chance agreement, showed that there was in fact a poor (36.3%) overall agreement between the observers. It is concluded that the correlation coefficient often overestimates the degree of true agreement, may conceal significant disagreements, and may give misleading information about reproducibility. The kappa statistic should always be used in the assessments of reproducibility of disability scales. Agreement between more than two sets of observations can also be assessed by estimating kappa.

UI	MeSH Term	Description	Entries
D009103	Multiple Sclerosis	An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)	MS (Multiple Sclerosis),Multiple Sclerosis, Acute Fulminating,Sclerosis, Disseminated,Disseminated Sclerosis,Sclerosis, Multiple
D012016	Reference Values	The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.	Normal Range,Normal Values,Reference Ranges,Normal Ranges,Normal Value,Range, Normal,Range, Reference,Ranges, Normal,Ranges, Reference,Reference Range,Reference Value,Value, Normal,Value, Reference,Values, Normal,Values, Reference
D012044	Regression Analysis	Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.	Regression Diagnostics,Statistical Regression,Analysis, Regression,Analyses, Regression,Diagnostics, Regression,Regression Analyses,Regression, Statistical,Regressions, Statistical,Statistical Regressions
D002561	Cerebrovascular Disorders	A spectrum of pathological conditions of impaired blood flow in the brain. They can involve vessels (ARTERIES or VEINS) in the CEREBRUM, the CEREBELLUM, and the BRAIN STEM. Major categories include INTRACRANIAL ARTERIOVENOUS MALFORMATIONS; BRAIN ISCHEMIA; CEREBRAL HEMORRHAGE; and others.	Brain Vascular Disorders,Intracranial Vascular Disorders,Vascular Diseases, Intracranial,Cerebrovascular Diseases,Cerebrovascular Insufficiency,Cerebrovascular Occlusion,Brain Vascular Disorder,Cerebrovascular Disease,Cerebrovascular Disorder,Cerebrovascular Insufficiencies,Cerebrovascular Occlusions,Disease, Cerebrovascular,Diseases, Cerebrovascular,Insufficiencies, Cerebrovascular,Insufficiency, Cerebrovascular,Intracranial Vascular Disease,Intracranial Vascular Diseases,Intracranial Vascular Disorder,Occlusion, Cerebrovascular,Occlusions, Cerebrovascular,Vascular Disease, Intracranial,Vascular Disorder, Brain,Vascular Disorder, Intracranial,Vascular Disorders, Brain,Vascular Disorders, Intracranial
D004185	Disability Evaluation	Determination of the degree of a physical, mental, or emotional handicap. The diagnosis is applied to legal qualification for benefits and income under disability insurance and to eligibility for Social Security and workmen's compensation benefits.	Disability Evaluations,Evaluation, Disability,Evaluations, Disability
D005069	Evaluation Studies as Topic	Works about studies that determine the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies.	Critique,Evaluation Indexes,Evaluation Methodology,Evaluation Report,Evaluation Research,Methodology, Evaluation,Pre-Post Tests,Qualitative Evaluation,Quantitative Evaluation,Theoretical Effectiveness,Use-Effectiveness,Critiques,Effectiveness, Theoretical,Evaluation Methodologies,Evaluation Reports,Evaluation, Qualitative,Evaluation, Quantitative,Evaluations, Qualitative,Evaluations, Quantitative,Indexes, Evaluation,Methodologies, Evaluation,Pre Post Tests,Pre-Post Test,Qualitative Evaluations,Quantitative Evaluations,Report, Evaluation,Reports, Evaluation,Research, Evaluation,Test, Pre-Post,Tests, Pre-Post,Use Effectiveness
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000203	Activities of Daily Living	The performance of the basic activities of self care, such as dressing, ambulation, or eating.	ADL,Chronic Limitation of Activity,Limitation of Activity, Chronic,Activities, Daily Living,Activity, Daily Living,Daily Living Activities,Daily Living Activity,Living Activities, Daily,Living Activity, Daily
D001168	Arthritis	Acute or chronic inflammation of JOINTS.	Oligoarthritis,Polyarthritis,Arthritides,Oligoarthritides,Polyarthritides