Discan

Last updated

Discan is both a scale and a method in clinical psychology. The term is a contraction of the words "discretized" and "analog" [1] and is also known as categorical analogue scales. [2]

As a scale, it is a type of ordered-metric scaling that yields a scale with internal reliability, and scale-points in excess of the number of initial anchors, more than would be the case with the Likert scale, though not as many as are achieved by the Analog scale. In Louis Thurstone's tradition, it is scored by paired-comparisons. Seeking optimality, it is a compromise between the competing merits and demerits of the Likert scale and the Analog scale. Its scoring system is a unitary non-transitional scales of severity that may have a maximum 8 or 10. [2]

With the Discan method, four descriptive anchor-levels yield 14 scale-points, or three levels produce ten, representing some of the possible values of intensity of the variable. [3] The method involves a series of repeated comparisons of the true or perceived levels using one or two reference levels. [3]

It was originated, for use in clinical psychology, by M.B. Shapiro. It was developed within a span of six years. [1] The Likert and analog scales—with the implicit assumption about the judgmental process of rating—are considered part of the Discan family. [1]

See also

Related Research Articles

<span class="mw-page-title-main">Psychological testing</span> Administration of psychological tests

Psychological testing is the administration of psychological tests. Psychological tests are administered by trained evaluators. A person's responses are evaluated according to carefully prescribed guidelines. Scores are thought to reflect individual or group differences in the construct the test purports to measure. The science behind psychological testing is psychometrics.

<span class="mw-page-title-main">Rensis Likert</span> American social psychologist

Rensis Likert was an American organizational and social psychologist known for developing the Likert scale, a psychometrically sound scale based on responses to multiple questions. The scale has become a method to measure people's thoughts and feelings from opinion surveys to personality tests. Likert also founded the theory of participative management, which is used to engage employees in the workplace. Likert's contributions in psychometrics, research samples, and open-ended interviewing have helped form and shape social and organizational psychology.

In the social sciences, scaling is the process of measuring or ordering entities with respect to quantitative attributes or traits. For example, a scaling technique might involve estimating individuals' levels of extraversion, or the perceived quality of products. Certain methods of scaling permit estimation of magnitudes on a continuum, while other methods provide only for relative ordering of the entities.

Questionnaire construction refers to the design of a questionnaire to gather statistically useful information about a given topic. When properly constructed and responsibly administered, questionnaires can provide valuable data about any given subject.

<span class="mw-page-title-main">Psychophysics</span> Branch of knowledge relating physical stimuli and psychological perception

Psychophysics quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they produce. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, more completely, as "the analysis of perceptual processes by studying the effect on a subject's experience or behaviour of systematically varying the properties of a stimulus along one or more physical dimensions".

<span class="mw-page-title-main">Likert scale</span> Psychometric measurement scale

A Likert scale is a psychometric scale commonly involved in research that employs questionnaires. It is the most widely used approach to scaling responses in survey research, such that the term is often used interchangeably with rating scale, although there are other types of rating scales.

<span class="mw-page-title-main">Personality test</span> Method of assessing human personality constructs

A personality test is a method of assessing human personality constructs. Most personality assessment instruments are in fact introspective self-report questionnaire measures or reports from life records (L-data) such as rating scales. Attempts to construct actual performance tests of personality have been very limited even though Raymond Cattell with his colleague Frank Warburton compiled a list of over 2000 separate objective tests that could be used in constructing objective personality tests. One exception however, was the Objective-Analytic Test Battery, a performance test designed to quantitatively measure 10 factor-analytically discerned personality trait dimensions. A major problem with both L-data and Q-data methods is that because of item transparency, rating scales and self-report questionnaires are highly susceptible to motivational and response distortion ranging all the way from lack of adequate self-insight to downright dissimulation depending on the reason/motivation for the assessment being undertaken.

A rating scale is a set of categories designed to elicit information about a quantitative or a qualitative attribute. In the social sciences, particularly psychology, common examples are the Likert response scale and 1-10 rating scales in which a person selects the number which is considered to reflect the perceived quality of a product.

<span class="mw-page-title-main">Self-report inventory</span> Type of psychological test

A self-report inventory is a type of psychological test in which a person fills out a survey or questionnaire with or without the help of an investigator. Self-report inventories often ask direct questions about personal interests, values, symptoms, behaviors, and traits or personality types. Inventories are different from tests in that there is no objectively correct answer; responses are based on opinions and subjective perceptions. Most self-report inventories are brief and can be taken or administered within five to 15 minutes, although some, such as the Minnesota Multiphasic Personality Inventory (MMPI), can take several hours to fully complete. They are popular because they can be inexpensive to give and to score, and their scores can often show good reliability.

Behaviorally anchored rating scales (BARS) are scales used to rate performance. BARS are normally presented vertically with scale points ranging from five to nine. It is an appraisal method that aims to combine the benefits of narratives, critical incidents, and quantified ratings by anchoring a quantified scale with specific narrative examples of good, moderate, and poor performance.

In sports, health and particularly exercise testing, the rating of perceived exertion (RPE), as measured by the Borg rating of perceived exertion scale, is a frequently used quantitative measure of perceived exertion during physical activity. In medicine this is used to document the patient's exertion during a test for the severity of diseases, and sports coaches use the scale to assess the intensity of training and competition as well as endurance. The original scale introduced by Gunnar Borg rated exertion on a scale of 6-20. Borg then constructed a newer category (C) ratio (R) scale, the Borg CR10 scale, rated on a scale from 1-10. This is especially used in clinical diagnosis and severity assessment of breathlessness and dyspnea, chest pain, angina and musculo-skeletal pain. The CR-10 scale is best suited when there is an overriding sensation arising either from a specific area of the body rather than overall exertion, for example, muscle pain, ache or fatigue in the quadriceps or from pulmonary responses during exertion.

The Montgomery–Åsberg Depression Rating Scale (MADRS) is a ten-item diagnostic questionnaire which psychiatrists use to measure the severity of depressive episodes in patients with mood disorders. It was designed in 1979 by British and Swedish researchers as an adjunct to the Hamilton Rating Scale for Depression (HAMD) which would be more sensitive to the changes brought on by antidepressants and other forms of treatment than the Hamilton Scale was. There is, however, a high degree of statistical correlation between scores on the two measures.

The visual analogue scale (VAS) is a psychometric response scale that can be used in questionnaires. It is a measurement instrument for subjective characteristics or attitudes that cannot be directly measured. When responding to a VAS item, respondents specify their level of agreement to a statement by indicating a position along a continuous line between two end points.

In medicine and psychology, clinical significance is the practical importance of a treatment effect—whether it has a real genuine, palpable, noticeable effect on daily life.

The Luria-Nebraska Neuropsychological Battery (LNNB) is a standardized test that identifies neuropsychological deficiencies by measuring functioning on fourteen scales. It evaluates learning, experience, and cognitive skills. The test was created by Charles Golden in 1981 and based on previous work by Alexander Luria that emphasizes a qualitative instead of quantitative approach. The original, adult version is for use with ages fifteen and over, while the Luria-Nebraska Neuropsychological Battery for Children (LNNB-C) can be used with ages eight to twelve; both tests take two to three hours to administer. The LNNB has 269 items divided among fourteen scales, which are motor, rhythm, tactile, visual, receptive speech, expressive speech, writing, reading, arithmetic, memory, intellectual processes, pathognomonic, left hemisphere, and right hemisphere. The test is graded on scales that are correlated to regions of the brain to help identify which region may be damaged. The Luria-Nebraska has been found to be reliable and valid; it is comparable in this sense to other neuropsychological tests in its ability to differentiate between brain damage and mental illness. The test is used to diagnose and determine the nature of cognitive impairment, including the location of the brain damage, to understand the patient's brain structure and abilities, to pinpoint causes of behavior, and to help plan treatment.

Hold tests are neuropsychological tests which measure abilities which are thought to be largely resistant to cognitive decline following neurological damage. As a result, these tests are widely used for estimating premorbid intelligence in conditions such as dementia, traumatic brain injury, and stroke.

<span class="mw-page-title-main">Cardinal voting</span> Electoral systems with independent candidate ratings

Cardinal voting refers to any electoral system which allows the voter to give each candidate an independent evaluation, typically a rating or grade. These are also referred to as "rated", "evaluative", "graded", or "absolute" voting systems. Cardinal methods and ordinal methods are two main categories of modern voting systems, along with plurality voting.

The minimal important difference (MID) or minimal clinically important difference (MCID) is the smallest change in a treatment outcome that an individual patient would identify as important and which would indicate a change in the patient's management.

The Brannon Masculinity Scale (BMS) is a self-report measure of endorsement of masculine norms. It was developed by Robert Brannon and Samuel Juni in 1984.

<span class="mw-page-title-main">General Behavior Inventory</span> Overview of the clinical use of the GBI a clinical assessment for bipolar disorder symptoms.

The General Behavior Inventory (GBI) is a 73-question psychological self-report assessment tool designed by Richard Depue and colleagues to identify the presence and severity of manic and depressive moods in adults, as well as to assess for cyclothymia. It is one of the most widely used psychometric tests for measuring the severity of bipolar disorder and the fluctuation of symptoms over time. The GBI is intended to be administered for adult populations; however, it has been adapted into versions that allow for juvenile populations, as well as a short version that allows for it to be used as a screening test.

References

  1. 1 2 3 Acta Psychiatrica Scandinavica: Supplementum. Munsgaard. 1989. pp. 12, 32.
  2. 1 2 Thornicroft, Graham; Tansella, Michelle (2010). Mental Health Outcome Measures, Third Edition. London: Royal College of Psychiatrists Publications. p. 39. ISBN   978-1-904671-92-3.
  3. 1 2 Singh, Avinash C.; Bilsbury, Christopher D. (January 1989). "Measuring Levels of Experiential States in Clinical Applications by Discan: A Discretized Analog Method". Behavioural and Cognitive Psychotherapy. 17 (1): 27–41. doi:10.1017/S0141347300015615. ISSN   2051-199X.

A staging approach to measuring patient-centred subjective outcomes. Bilsbury CD, Richman A. Acta Psychiatr Scand Suppl . 2002;(414):5-40.