Class 16: Rigor in quantitative researc

Rigor

Strictness or precision with which a study is conducted

Ensures quality, believeability and trustworthiness of the findings

How is rigor achieved in quantitative research

Through valid and reliable measureable instruments

Reliability

Consistency and dependability of a research instrument and ots ability to produce the same results on repeated measures

Reflects the proportion of accurcy to inaccuracy

Includes: stability, homogenity (internal consostency) and equivalence

Stability

Porduces same results with repeated testing

Homogenity (internal consistency)

All items measure same concept or characteristic

Equivalence

Produces consistent results using equivalent or parallel forms

Alpha (reliability) coefficient

Reflects consitency of a measurement instrument

Shows true relationship between true variance, error variance and observed score

Alpha coefficient range

From 0-1

Closer to 1: high reliability (low error)

Closer to 0: Low reliability (high error)

0.7 or more is generally acceptable, depdnding on the tool

Validity

Whether an instrument accurately measures the concept it intends to

Must be reliable to be valid, but reliability doesnt guarantee vaklidity

3 types: content, criterion related, and construct

Content validity

Instrument covers all aspects of content

Define the concept, develop items, expert review

Criterion related validity

Degree of relationship between a participants performance ona measurement tool and their actual behaviour

The second measure

Types: concurrent and predictive

Construct validity

Instrument truly measures the theoeretical construct of interest

Validates underlying theory

Approaches: hypothesis testing, convergent and divergent methods, contrasted groups approach

Face validity

Basic, intuituive form of validity where the instrument appears to measure intended concept

Not a sibsititue for more rigorous forms

Concurrent validity

Correlation between 2 measures of the same construct adminsitered at the same time

Predictive validity

Correlation between a measure and a future measure of the same construct

What do psychometric assessments provide evidence for?

An instrument’s reliability and validity, ensuring conclusions are sound and useful.

Why must researchers evaluate measurement instruments in a study?

To check reliability and validity, which affect the study’s accuracy and usefulness.

What is required when developing new research instruments?

Establish their reliability and validity as part of the research process.

Why assess instruments when critiquing quantitative studies?

Because instrument appropriateness, reliability, and validity directly affect internal and external validity.