1. Threats to the Internal Validity of Experimental and Quasi-Experimental Research in Healthcare
- Author
-
Laura T. Flannelly, Katherine R B Jankowski, and Kevin J. Flannelly
- Subjects
Research design ,Health (social science) ,Operations research ,Computer science ,media_common.quotation_subject ,Statistics as Topic ,Control (management) ,03 medical and health sciences ,0302 clinical medicine ,Bias ,030502 gerontology ,Health care ,Selection (linguistics) ,Humans ,Internal validity ,Mortality ,media_common ,Variables ,business.industry ,Patient Selection ,Design of experiments ,Religious studies ,Reproducibility of Results ,Regression analysis ,Clinical Psychology ,Data Interpretation, Statistical ,030220 oncology & carcinogenesis ,Health Services Research ,0305 other medical science ,business - Abstract
The article defines, describes, and discusses the seven threats to the internal validity of experiments discussed by Donald T. Campbell in his classic 1957 article: history, maturation, testing, instrument decay, statistical regression, selection, and mortality. These concepts are said to be threats to the internal validity of experiments because they pose alternate explanations for the apparent causal relationship between the independent variable and dependent variable of an experiment if they are not adequately controlled. A series of simple diagrams illustrate three pre-experimental designs and three true experimental designs discussed by Campbell in 1957 and several quasi-experimental designs described in his book written with Julian C. Stanley in 1966. The current article explains why each design controls for or fails to control for these seven threats to internal validity.
- Published
- 2018
- Full Text
- View/download PDF