Procedures for validating an instrument
Some qualitative researchers reject the concept of validity due to the constructivist viewpoint that reality is unique to the individual, and cannot be generalized.
These researchers argue for a different standard for judging research quality.
Consider the SAT, used as a predictor of success in college.
It is a reliable test (high scores relate to high GPA), though only a moderately valid indicator of success (due to the lack of structured environment – class attendance, parent-regulated study, and sleeping habits – each holistically related to success).
(the process of developing, testing, and using the device).
Instruments fall into two broad categories, researcher-completed and subject-completed, distinguished by those instruments that researchers administer versus those that are completed by participants.
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?
An instrument that is externally valid helps obtain population generalizability, or the degree to which a sample represents the population.For a more complete discussion of trustworthiness, see Lincoln and Guba’s (1985) chapter.—Seven stages were used to assess face, content, and criterion validity of the rugby union injury report form.Thus far, we have discussed Instrumentation as related to mostly quantitative measurement.Establishing validity and reliability in qualitative research can be less precise, though participant/member checks, peer evaluation (another researcher checks the researcher’s inferences based on the instrument (Denzin & Lincoln, 2005), and multiple methods (keyword: ), are convincingly used.
Researchers chose which type of instrument, or instruments, to use based on the research question.