· Introduction Quantitative research methodology uses a deductive reasoning process (Erford, 2015, p. 5). It is based on philosophical assumptions that are very different from those that support qualitative research. Quantitative studies fall under what is broadly described as a positivist perspective. Epistemologically, knowledge is something that is believed to be objective and measurable, and the nature of reality (that is, ontology) is such that there is one fixed, observable, and definable reality. Quantitative approaches to research emphasize the objectivity of the researcher, and because a goal is to uncover the one true reality, values (axiological assumptions) and the subjective nature of experience are not likely to be examined. Quantitative Research Designs Quantitative research can be categorized in different ways. Brief descriptions of some designs appear below. The chosen research design is determined by the nature of the inquiry, that is, what the researcher wants to learn by conducting the study. Counseling Research: Quantitative, Qualitative, and Mixed Methods thoroughly describes several major reseach. Experimental Research Experimental research, one of the quantitative designs, involves random selection and random assignment of subjects to two or more groups over which the researcher has control. This is what distinguishes experimental studies from the other designs. Experimental studies in counseling are not that common, because many research questions do not lend themselves to random selection and assignment for ethical reasons. Experimental studies compare the effect of one or more independent variables on one or more dependent variables. Independent variables fall into two broad categories. One type of independent variable involves measuring some characteristic inherent in the study's participants, such as their age, gender, IQ, personality traits, income, or education level. These demographic or blocking variables are not something which the researcher can manipulate, though the researcher can statistically control for them. The treatment or experimental conditions that the researcher sets up is the other type of independent variable, which is unique to experimental designs. The element of control is what permits researchers to conclude that one variable has caused a change in another variable. Quasi-Experimental Research Quasi-experimental research designs come in many different forms. Like experimental research, the researcher aims to compare the effect of the independent variable under their control on the dependent variable. However, the researcher does not or cannot randomly assign individual participants to treatment and control groups, so cause-and-effect relationships cannot be as strongly inferred from the results. Pre-existing conditions of one group in comparison to the other may confound the findings. An example might be a study to examine the potential effects of a new curriculum aimed at reducin.