sports science & Physical Education:Test Validity

Validity refers to the degree to which a test measures what it was designed to measure. To the beginner in the field of test and measurements, this concept may seem so basic that it scarcely deserves mention. Nevertheless, many test are found to be rather weak in this most basic consideration.Probably every student has had the unnerving experience of being given a test that seems to pertain to some course other than the one in which her or he is enrolled.In such cases the test fails in content validity by not being related to the material that has been covered in the course. Another example of poor test validity is the case of student who can beat everyone in the class,say in tennis,but whose grade is lowered because hi does poorly on one skill test(say,catching the ball off the wall). In this instance the teacher,in his or her zeal to employ objective measurement,has overlook their main function to supplement other means of evaluation.In addition to the teacher's misuse of the test,the test itself did not represent an accurate measure of ability to play tennis.We should hasten to say that,in many cases,volleying tests demonstrate high validity.The point we are attempting to make with this example is that the tests constituted a somewhat artificial setting and it touched on only a small facet of the game.For a test to be valid, a critical analysis must be made as to the nature of the activity it is to measure and the skills and special ability that are involved.Since testing has different purposes and since validity refers to the degree to which a test achieves its purpose,it follow that there are different types of validity.I will briefly describe four kinds of validity and ways by which validity may be established in my next issue.