Page 1 :
280 9. TOOLS AND METHODS OF DATA COLLECTION, VALIDITY OF RESEARCH TOOL, , to which an instrument measures wi, 8 What i, , ~alidity of an instrument refers to the degree stru, pest Ae measuring instrument jg sup, , supposed to be measuring. For example, a temperature: ee salah Poet i, measure only the temperature; it cannot be considered a valid instrument if i mea, ti, attribute other than temperature. Similarly, ifa resea rcher developed a tool to mea, pain, and if it also includes the items to measure anxiety, ;, , Therefore, a valid tool should only measure what it supposed to be measuring,, , ), sUro,, , an, : ‘ Ure, it cannot be considered ava © the, , lid too), , Definitions, According to Treece and Treece, ‘Validity refers to an instrument or test actually testing what it, is supposed to be, testing’, Dats, , According to Polit and Hungler, ‘Validity refers.to. the degree to which an instrument meas, tres, , what it is supp osed_to be measuring’., According to American Psychological Foundation, ‘Validity is the appropriateness, meanj, fullness, and usefulness of the interference made from the scoring of the instrument’., , ‘, ng,, , Validity is the appropriateness, completeness, and usefulness of an attribute measuring research, instrument., , Types of Validity, Basically validity is classified into following four categories., , * Face validity: Face validity involves an overall look of an instrument regarding its approPriateness to measure a | particular attribute or phenomenon. Though face validity is not”, considered a very important and essential type of validity for an instrument. However, it, may be taken in consideration while assessing for other aspects of validity of a research, instrument. In simple words, this aspect of validity refers to the face value or the outlook, of an instrument. For example, a Likert scale designed to measure the attitude of the nurses, towards the patients admitted with HIV/AIDS; a researcher may judge the face value of, this instrument by its appearance, that is it looks good or not; but it does not provide any, guarantee about the appropriateness and completeness of a research instrument with re, gard to its content, construct, and measurement score., , ity: It is concered with scope of coverage of the content area to be me, it is applied in of knowledge measurement. It is mostly used in, , complex psychologic tests of a person. It is a case of expert judgment about the, , content area included in the research instrument to measure a particular phenomeno”, , Judgement of the content viability may be subjective and is based on previous researchers, , and experts opinion about the adequacy, appropriateness, and completeness of the content, , i : - ai % t, ee Generally, this viability is ensured through the judgments of experts abou, , , , , , , , , , we . e, type of validity is a relationship between measurements ot S, iemal criteria. For example, a tool is developed to ™, , sure the professionz | ~ exe, : among nurses and to assess the criterion validity nurses “, , , , , , ~ vo, , pre, , 107, p?, the, nut, 4, yal, ext, fou, cal, fic, am, , £8, , Ci, bar, _—, P, it, oO!, ti, a, ;, , is