Research Design Quantitative Quantitative Research Design Quantitative Research

Research Design Quantitative

Quantitative Research Design • Quantitative Research is the cornerstone of evidence-based practice • It provides the knowledge for practice in a way that is measurable and that can be replicated • It uses measurement to determine the effectiveness of an intervention or the relationships seen among variables and to report these with a certain level of confidence • Numbers are unambiguous and identify truths in a universally recognized way.

Quantitative Research Design • Quantitative design is used to: – Determine the effects of an intervention – it can isolate and evaluate the effects of an intervention - the independent variable on a specific outcome – the dependent variable – Measure relationships between or among variables – Measure change, or lack of change, over time

Steps in Quantitative Research • • Identify the problem Determine the purpose Review the literature Select a framework into which the problem fits • Formulate research questions and hypotheses • Define the study variables

Steps in Quantitative Research • • Select the research design Identify the population of interest Select the method to use for sampling Conduct a pilot study (if necessary) Collect and organize the data Analyze the data Interpret the findings Communicate and use the findings

Quantitative Study Designs • Characteristics of True Experiments – Manipulation – the experimenter does something to at least some of the subjects. The experimenter varies the independent variable and observes the effect that the manipulation has on the dependent variable. – Control – the experimenter introduces one or more controls over the experimental situation including the use of a control or comparison group. Scientific evidence requires making at least one comparison – comparison with the norm can be assumed

Quantitative Study Designs • Characteristics of True Experiments cont. – Randomization – the experimenter assigns subjects to a control or an experimental group on a random basis. Randomization remains the most trustworthy and acceptable method of equalizing groups. • Settings for True Experiments – Settings can be in the field or in the laboratory. Since control is important, field experiments are much more difficult because of contamination of treatments – people may talk to each other and tell what’s happening

Quantitative Research Considerations • When comparisons are made in quantitative research they can be: – Comparisons of two or more groups – Comparisons of one group at two or more points in time – Comparisons of one group under different circumstances or conditions – Comparisons of relative rankings