Validity and Reliability

Content validity is achieved when the content of the assessment matches the educational objectives. Criterion validity is demonstrated by the ability of the test to relate to external requirements. Construct validity takes into account the educational variables, such as the native language of the students, to predict the test outcomes. Reliable assessments have consistent results; Reliability refers to the consistency of a measure. A test is considered reliable if we get the same result repeatedly.

Why is internal consistency such an easy way to assess reliability from a methodological perspective?

Evaluating human services is a task that can be very complex. People can have different interpretations of the same event. Another concern is that people are not always honest. Therefore, human services will gain from effective, high quality evaluations of data collection methods. This requires that the data collection methods supply accurate and dependable information. This paper will define and describe 2 concepts of measurement known as reliability and validity,-provide examples and supporting facts as to how these concepts apply to data collection in human services, and evaluate the importance of the validity and

In the surveys and randomized controlled trials, validity, reliability and generalizability are three key factors.

It is made up of four major parts: standards for particular applications, technical standards for test construction and evaluation, professional standards for test use, and standards for administrative procedures. A test that is technically adequate meets the criteria for validity, reliability, and norms. Validity is “the appropriateness, meaningfulness, and usefulness of the specific inferences” that can be made from the test results. (American Psychological Association 9) Validity is the degree to which a test measures what it is intended to measure. Reliability is the extent to which the test results are dependable and consistent. Unrelated to the purpose of the test, errors in measurement can be viewed through inconsistencies in the performance, motivation, or interests of students being tested. Norms can be shown in age or grade equivalence, standard scores, and percentiles. They are generally shown in charts showing the performance groups of students who have taken the test. Norms show the comparison of the performance of new groups of test takers with the samples of students on whom the test was standardized. Goodwin and Driscoll (59-60) note that standardized tests have the following qualities: They provide a “systematic procedure for describing behaviors, whether in terms of numbers or categories.” They have an established format and set materials. Also, they present the same tasks and

|What criterion must be met |Consistency: Important when comparing data to make sure the data compared was prepared the correct way and done the same each time. |

The second form of reliability is the test-retest reliability. This kind of reliability is used to assess the consistency of a measure from one period of time to another. This reliability is estimated when the same test is administered to the same sample group but at two different periods in time. This approach makes an assumption that there is no substantial change in the construct that is being measures in the two different occasions(Rosnow & Rosenthal, 2012).

Empirical or predictive validity is the extent to which scores on one assessment correspond to the same behaviors measured with other assessment instruments. For an assessment to be empirically valid, statistical evidence must suggest the instrument measures what it is meant to measure (Trochim, 2006). The BDI-FastScreen was correlated with two other assessment instruments that measure symptoms of depression and with the diagnostic criteria for depression in the Diagnostic and Statistical Manual of Mental Disorders IV-TR (DSM-IV-TR). The correlations were r = .62 with the Hospital Anxiety and Depression Scale and r = .86, when correlated with the Beck Anxiety Inventory for Primary Care. Correlation with the DSM-IV-TR was

___IV. Practical Aspects - This book provides detailed descriptions on tests including specific data for purpose

The validity of a test if very important, because it can make or break a test. The purpose of a test is to measure something specific. If the test has low validity it is not measuring what it supposed to measure. The Holland codes validity is measured through the different personality types. The test has shown to accurately predict a possible career choice for each participants (O’Connell 1971).

There are also issues relating to reliability which may affect the diagnosis. One type is Test-retest reliability, which occurs when a practitioner makes the same consistent diagnosis on separate occasions from the same information. In terms of depression this can be applied if the same Doctor or Psychiatrist gives a patient a diagnosis of depression on two separate occasions. The other is Inter-rater reliability occurs when several practitioners make identical, independent diagnoses of the same patient. This can be applied to depression by confirming that the diagnosis of depression is accurate in a given situation.

The results obtained in the three tests described above are consistent with the outcome of

Values and Motives Questionnaire: The Technical Manual (n.d.). Retrieved from the Liberty COUN 521 website: Psytech International.

The Values and Motives Questionnaire, also known as the Values and Motives Inventory, is designed to examine a person’s motivation in relation to his values and activities. In order to ensure a comprehensive understanding of values, the VMQ assess three distinct areas, including: interpersonal, intrinsic, and extrinsic. Interpersonal values, according to the VMQ refer to one’s relationships with others. Intrinsic values contain one’s personal beliefs and attitudes. Finally, extrinsic values are one’s motivating factors at the workplace. Each of these three areas contain twelve topics

The manual discusses internal consistency and test-retest in terms of reliability. Internal consistency is measuring how scores on individual items relate to each other or to the test as a whole. In two subsample studies, high internal consistency was found. In the first study, with a mixed sample of 160 outpatients, Beck, Epstein et al. (1988) reported that the BAI had high internal consistency reliability (Cronbach coefficient alpha = .92), and Fydrich et al. found a slightly higher level of internal consistency (coefficient alpha = .94). This means that the items on the BAI are all measuring the same variable, anxiety.