Quantitative research is rooted in numerical approaches. The emphasis is on objectivity and the use of statistics or data gathered through polls, questionnaires or surveys. With quantitative research methods, numerical data are gathered and then generalized across groups of people to explain trends or phenomena. These methods begin from questions such as "how many?" "how often?" "when?" and "where?"

The Strengths of Quantitative Approaches

With the use of quantitative research methods, personal bias can be avoided in studying research problems in the social sciences. It's easier with these tools to generalize the results, as well as to study broadly. These research methods produce hard numbers that can be turned into statistics.

Financial analysts often use quantitative research to gather information about the performance of stocks or bonds. Market researchers conduct surveys to learn about the demographics of their customers, including age, gender, education and socioeconomic status. The U.S. Census is an example of large-scale quantitative data gathering; census-takers survey households and the data are crunched to determine the federal budget.

The Limitations of Quantitative Approaches

Because quantitative research methods produce primarily numerical descriptions, they don't yield rich details about behavior, attitudes or emotions. Often, because the research is carried out in sterile or artificial environments such as labs, the results don't accurately reflect real-world situations. The data for a quantitative study are usually gathered in a fairly rigid way and therefore don't inspire discovery. Structural bias can creep in when questions used in research are standard or tend to reflect the experiences or viewpoints of researchers instead of those of participants. When people need to be observed in their daily routines, for example, quantitative research is not the best way to capture those data.

Quantitative Research at Its Best

Quantitative approaches are best when the need is to compare data systematically, such as a comparison between groups or countries. Quantitative research also lends itself to looking at the general features of a population. Before undertaking a study, researchers need to consider their specific goals. If they're primarily interested in generalizing the findings to the larger population, for example, quantitative methods are best. However, if there is stronger interest in deep meanings than in numbers, quantitative approaches are not best. Qualitative methods, which describe and use rich detail or observation, are a good alternative to quantitative methods for some studies.

When Quantitative Methods Should Be Applied

When researchers are interested in determining the effects of a hand-washing program on a group of grade-school children, quantitative methods are ideal. This is because quantitative research tests theory and cause-and-effect relationships. If the goal, on the other hand, is to explore the role that hope or optimism plays in the experiences of women with ovarian cancer, qualitative approaches will be more effective. Qualitative methods develop theory, in contrast to quantitative approaches, through the use of in-depth interviews or observation. They are not mathematical in nature, but narrative.