<prompt> The response which is graded by an observer on an agree or disagree continuum is based onVisual analog scaleGuttman ScaleAdjective scaleLikert Scale  <response>: Likert Scale: Refer to Theory.Visual analog scale VAS: VAS is a measurement instrument that tries to measure a characteristic that range across a continuum of values and cannot easily be directly measured For example, the amount of pain that a patient feels ranges across a continuum from none to an extreme amount of pain. From the patients perspective this spectrum appears continuous as their pain does not take discrete jumps, as a categorization of none, mild, moderate and severe would suggest Operationally a VAS is usually a horizontal line, 100 mm 10 cms in length, anchored by word descriptors at each end: patient marks on the line the point that they feel represents their perception of their current state VAS score: is determined by measuring in millimetres from the left hand end of the line to the point that the patient marks Continuous or analogue aspect of the scale differentiates it from discrete scales such Likert scale Is quite used in Anaesthesia.Guttman Scale: Is also known as Cumulative scale Contains a series of statements that expresses increasing intensity of a characteristic AND respondent is asked to agree or disagree to with each statement For example: Asbestos can cause lung cancer Asbestos is an important cause of lung cancer Asbestos is a very important cause of lung cancer and death Asbestos is the most important cause of lung cancer an death in India Perfect Guttman scale: consists of a uni-dimensional set of items that are ranked in order of difficulty from least extreme to most extreme positionAdjectival scale: Is a linguistic scale is a set of words, of the same grammatical category, which can be ordered by their semantic strength or degree of information For example, lukewarm, warm, and hot fall along a single adjectival scale since they indicate a variation in the intensity of temperature of the modified noun. 