Читать книгу Practitioner's Guide to Using Research for Evidence-Informed Practice - Allen Rubin - Страница 61

As is discussed in Chapter 1, common questions to ask in selecting the best assessment instrument pertain to whether the instrument is reliable, valid, sensitive to small changes, feasible to administer, and culturally sensitive. Most of the studies that assess reliability, validity, and cultural sensitivity use correlational designs. For reliability, they might administer a scale twice in a short period to a large sample of people and assess test-retest reliability in terms of whether the two sets of scale scores are highly correlated. Or they might administer the scale once and see if subscale scores on subsets of similar items correlate to each other. For validity, they might administer the scale to two groups of people known to be markedly different regarding the concept being measured and then see if the average scores of the two groups differ significantly. For sensitivity, they might use a pretest-posttest design with no control group and administer the scale before and after treatment to see if the scale can detect small improvements. Although experiments and quasi-experiments are rarely the basis for assessing a scale's validity or sensitivity, it is not unheard of for an experiment or a quasi-experiment to provide new or additional evidence about those features of a scale. That is, if a treatment group's average scores improve significantly more than the control group's, that provides evidence that the scale is measuring what the treatment intends to affect and that the scale is sensitive enough to detect improvements. W return to these issues and cover them in greater depth in Chapter 11. That entire chapter is devoted to critically appraising and selecting assessment instruments.