Steps in validating an instrument
This would involve taking representative questions from each of the sections of the unit and evaluating them against the desired outcomes. Does the instrument consistently measure what it is intended to measure?It is not possible to calculate reliability; however, there are four general estimators that you may encounter in reading research: Reliability is directly related to the validity of the measure. First, a test can be considered reliable, but not valid.If they are not, the information collected from a study is likely to be biased or factually flawed, doing more harm than good. External validity refers to how well your study reflects the real world and not just an artificial situation.
Therefore, the instruments used to evaluate research data must be valid and precise.
It is rare, if nearly impossible, that an instrument be 100% valid, so validity is generally measured in degrees.
As a process, validation involves collecting and analyzing data to assess the accuracy of an instrument.
For a more complete discussion of trustworthiness, see Lincoln and Guba’s (1985) chapter.