While there are many types of quantitative research designs, they generally fall under one of two umbrellas: experimental research and non-experimental research. The four most commonly used designs for research studies are descriptive, correlational, quasi-experimental, and experimental.”(Grove, Gray & Burns, 2015). Types Of Quantitative Research Designs Nursing Assignment Papers.
In experimental design researchers uses random assignment and they manipulate an independent variable around a controlled variable. It is an objective, systematic, and highly controlled investigation conducted for predicting and controlling phenomena (Grove, Gray & Burns, 2015). A true experimental design there must be randomization, a control group and manipulation of a variable when examining the direct cause or predicted relationships between variables. In a quasi-experiment one of these aspects is missing (Sousa, Driessnack & Menders, 2007).