validity and reliability in quantitative studies

research design, operational definitions, how variables are measured, and what is (not) measured (Huitt, Hummel & Kaeck, 1999).

Therefore, on the one hand, internal validity refers to how well the study is run, e.g. Confounding variables are variables that the researcher fails to control or eliminate, allowing the results to show false correlation (Shuttleworth, 2008). A study is internally valid if there are as little confounding variables as possible. Therefore, its quality can be assessed by its (a) internal and (b) external validity, (c) reliability and (d) objectivity (Lincoln & Guba, 1985), which are described below: a) Internal validityĪ study is internally valid if it is able to determine whether a causal relationship exists between one or more independent variables and one or more dependent variables (Heffner, 2017), i.e. Data is usually generated by means of surveys and experiments and analyzed through statistical tests such as ANOVA (e.g. 154) define quantitative research as „entailing the collection of numerical data and exhibiting the view of relationship between theory and research as deductive, a predilection for natural science approach, and as having an objectivist conception of social reality“. 1) Quantitative Researchīryman and Bell (2005, p. In order to appreciate the quality of academic research, it makes sense to apply different criteria for (1) quantitative and (2) qualitative methods. Due to this, methodology, methods and results naturally differ accordingly (Goertz & Mahoney, 2012).

Quantitative and qualitative research is based on different research paradigms that reflect the researcher’s scientific worldview. „A man is more likely to believe something if he would like it to be true.“ - Francis Bacon

Validity and reliability in quantitative studies