Reliability and Validity

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Reliability and validity are essential in terms of observation and measurement as it relates to human services research. In order to ensure this particular research has legitimacy it is vital that testing and research is consistent and specific. This paper will define and describe the types of reliability and validity and provide examples of each as it relates to human services research. It will also provide examples of how data collection methods and instruments are used in relation to human services research as well as managerial research. Reliability is an important criterion in regards to research and refers to the degree of consistency or stability of a measure. Reliability refers to consistency, stability or dependability (Rosnow & Rosenthal, 2008). High reliability of a particular measure will be one that produces similar results under consistent conditions. There are four forms of reliability used in human services research and are as follows: alternate-form reliability, internal-consistency reliability, item-to-item reliability and test-retest reliability.Alternate-form reliability refers to the degree of relatedness of different forms of the same test. In other words, it measures results obtained by alternate versions of the same test in order to determine equivalence congresscongress

An example of alternate-form reliability as it pertains to human services research would be tests given to develop national aptitude tests. Both tests (Form A and Form B) must have conditions that involve the same construct and knowledge base. Each test is given to the same group of individuals and both scores are correlated and used to determine the reliability of the test. The test that yields the most consistent answers is then used. Internal-consistency reliability, also known as reliability of components, is the overall degree of relatedness of all items between two raters (Rosnow & Rosental). This form of reliability is very useful in human services research when using observation in that raters will not assess the same situation to the same degree or respond to the same questions in the same manner. An example of internal-consistency reliability is to have people categorize pictures of animals or objects with the perception being that all participants will classify these pictures the same congressItem-to-item reliability deals with the relationship of one item with those to another item (Rosnow & Rosenthal, 2008). It is the reliability of any single item on average. Test-to-retest reliability is a form of reliability that is obtained by administering the same test twice over a period of time in which the assessment should yield the same results. In other words, test-to-retest reliability evaluates reliability across a time frame. Reliability can vary on account of many factors that affect how a person responds to the test, such as mood, interruptions, and/or time of day. A good test will take such factors into consideration and give relatively little variation, while an unreliable test is highly sensitive to such factors and will give widely varying results. Basically, the longer the delay between tests, the greater the variation.Similarly, validity is just as important as reliability when conducting research. Validity is used to measure how well certain research designs fulfill their purpose. It is defined as the degree to which what was observed or measured within a research is the same as what was purported to be observed or measured. Simply put, validity is the extent to which a test measures what it claims to measure. The types of validity are as follows: construct validity, content validity, convergent and discriminant validity, criterion validity, external validity, face validity, internal validity and statistical-conclusion validity.Construct validity seeks agreement between a theory and a specific measuring device or procedure and how well that measurement confirms the theoretical concept. Content validity addresses whether the test adequately samples relevant material (Rosnow & Rosenthal, 2008). Convergent validity is supported by a substantial correlation of conceptually similar measures, whereas, discriminant validity is supported by a lack of correlation between conceptually unrelated measures (Rosnow & Rosenthal, 2008). Furthermore, criterion validity is the extent to which a measure correlates with one or more criterion variables (Rosnow & Rosenthal, 2008). External validity is degree of generalizability, while face validity is the extent to which a test seems on its surface to be measuring what it purports to measure (Rosnow & Rosenthal, 2008). Additionally, face validity is used to determine whether a measurement is intuitive or reasonable. Internal validity is the degree of validity of statements made about whether X causes Y (Rosnow & Rosenthal). Lastly, statistical-conclusion validity is the accuracy of determining a certain statistical conclusion.Human services and managerial researchers use many data collection methods and instruments. Most researchers use systematic observational research and self-report measures. Self-report measures heavily depend upon participants' disclosure of requested information. The most common forms of self-reported data collection are interviews and surveys. Both can be conducted in person, over the phone, or online. Interviews consist of a set of questions that are usually open-ended, allowing the participant to provide a detailed response (Rosnow & Rosenthal, 2008). Surveys or questionnaires can also be open-ended, but there is also the option of creating fixed-choice questions. Systematic observational research is a strategy that researchers use to observe occurrences with the intent of devising a scientific explanation. They do so by using a set of standards with which to measure their observations against (Rosnow & Rosenthal, 2008). Observational research is conducted through several means, such as participant observation and content analysis. Participant observation is a method in which researchers decide to place themselves in the environment they wish to study and participate in the activities. Content analysis is the usage of materials, such as newspapers, magazines, journals and other research.In regards to research, reliability and validity are essential in determining the legitimacy of a particular study. Human services require evidence based data to support the administration of certain tests that consistently yield the same results. It is essential that data collection is accurate and reliable, and also valid with respect to being able to concisely measure the intended subject matter. Overall, the reliability and validity of testing methods are important because they assist future actions and decisions of human services research.More info

 

They do so by using a set of standards with which to measure their observations against (Rosnow & Rosenthal, 2008). Observational research is conducted through several means, such as participant observation and content analysis. Participant observation is a method in which researchers decide to place themselves in the environment they wish to study and participate in the activities. Content analysis is the usage of materials, such as newspapers, magazines, journals and other research.In regards to research, reliability and validity are essential in determining the legitimacy of a particular study. Human services require evidence based data to support the administration of certain tests that consistently yield the same results. It is essential that data collection is accurate and reliable, and also valid with respect to being able to concisely measure the intended subject matter. Overall, the reliability and validity of testing methods are important because they assist future actions and decisions of human services research.More info


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