Practical Research - Instrumentation in Quantitative Research

Validity

Validity

degree to which the instrument measures what it intends to measure. It involves collecting and analyzing data to assess the accuracy of an instrument

Face Validity

simplest and easiest type of validity where in the validator skim the surface of the instrument in order to form an opinion. Moreover, it is often criticized as the weakest form of validity

Content Validity

appropriateness of the content of an instrument. A type of validity that most often includes expert or people familiar with the construct being measured. The expert make judgement about the degree to which the items in the questionnaire match the objective of the study.

Criterion Validity

measures how well the relationship between a measure and an outcome.

Construct Validity

how well a test measures what it claims to measure. It is used to know whether the operational definition of a construct align to the true theoretical meaning of a concept.

Stability or Test-retest reliability.

simplest type of reliability where in the same questionnaire is administered twice and correlation between two set of score is computed.

Split-half method

Also called equivalent or parallel forms. This is done by administering two different set of questionnaire but with same topic and correlation between two set of score is computed.

Internal consistency

when the instrument measures a specific concept. It is estimate based on a single form of test administered on a single occasion.