Quantitative research is quantifying the relationship between the dependant and independent variables. This relation ship is expressed through using statistical effects such as correlations, relative frequencies, or differences between the mean. Variables can be things like weight, temperature, length, time and treatment. Quantitative research studies are objective, deductive (test the theory), generalizable and it uses the data in the form of numbers as compare to qualitative research studies.
Quantitative research methods are used in the market:
• When we want to know how many and how often
• When we want to outline the behaviors and intentions of the target audience on selected determinants or variables and weather these determinants predict a behavior at statistical level significantly.
Quantitative market research generally involves surveying a large group of people (usually several hundred) using a closed ended questionnaires.
Quantitative research is an excellent way of finalizing the results and proving and disapproving the hypothesis. Its structure has not changed for centuries so it is considered standard across many disciplines. The results of the quantative research can be published legitimately by receiving the comprehensive answers through statistical analysis. The results obtained from this research are unbiased and real because of the elimination of external factors. Quantative experiments are useful for verifying the results obtained from series of qualitative experiments, leading to final answer and tapering down to possible direction for further research.
Quantitative experiments can be time consuming and expensive. They should be wisely planned to ensure complete randomization and correct designation of the control groups. There is strict requirement of statistical confirmation of results which is a big hindrance as all scientists are not good at statistics. In some of the experiments while proving the hypothesis there is always some ambiguity which requires another investment of time and resource.Quantative studies generate only yes, no response or proven or unproven results. For social sciences, education, anthropology and Psychology human nature is much more complex than these simple yes no answers and quantative research is unable to solve it.
Types of Study
The studies aiming at quantifying the relationship are of two types
• Descriptive Study
• Experimental Study
A descriptive study may be used to, develop theory, identify problems with current practice, justify current practice, make judgments or identify what others in similar situations may be doing. The descriptive studies are also called observational studies. As in this study the researcher observe the variables without intervening them. These studies describe the pattern and occurrence of any phenomena in relation to variables such as person, time and place and are often first step to new topic, event and condition. These studies can be divided in to two roles i.e. the studies which describe and emphasize the feature of new condition of individual and those which describe the state and condition of communities and population. Case reports, case-series reports, before-and-after studies, cross-sectional studies and surveillance studies deal with individuals. Ecological Studies examine populations.
Descriptive studies can indicate the relation ship between the variables but cannot establish the causality. The descriptive studies do not have comparison or control group which means that they do not allow the interference to be drawn about associations. However they can suggest the hypothesis which can be tested in analytical observational studies.
The types of descriptive studies include:
This is the simplest form of descriptive study and it reports the data on the single subject. They represent the first clue in identification of any extra ordinary or unusual trend. Examples are a study of an outstanding athlete or of a dysfunctional institution.
A descriptive study on few cases is called case series. It is a report on series of individuals with an outcome of the interest. Another way of defining a case series is that the case series are collection of individual case reports which may occur within a short period of time and these are aggregated in to one publication. No control groups are involved in it. An advantage of case series over case report is that a case series can help formulate a new and useful hypothesis rather than merely documenting an interesting medical oddity. However, its disadvantage is that it cannot be used to test for the presence of a valid statistical association.
Cross sectional study
In this study variables in a sample of subjects are examined once and then relationships between them are determined. The cross-sectional survey is sometimes referred to as a prevalence study and it can survey or assess the health status of a population – e.g. Health Survey of England.
In prospective or cohort studies, some variables are examined at the start of a study (e.g., dietary habits), then after a period of time the outcomes are determined (e.g., incidence of heart disease). This study is also called longitudinal study.
Case control Study
Case-control studies compare cases (subjects with a particular attribute, such as an injury or ability) with controls (subjects without the attribute); comparison is made of the exposure to something. For example volume of high intensity training, or number of alcoholic drinks consumed per day. Case-control studies are also called retrospective, because they focus on conditions in the past that might have caused subjects to become cases rather than controls.
Ecological co relational studies look for associations between exposures and outcomes in populations rather than in individuals. They use data that has already been collected. The measure of association between exposure and outcome is the correlation coefficient r. This is a measure of how linear the relationship is between the exposure and outcome variables.
In this study measurements are taken, interventions are done based on these measurements and then again measurements are done to see what happened. The experimental studies are also known as repeated measure studies or intervening studies. In this the researchers decide which treatment the participants must get and participants are assigned to treatment group in random manner. This randomization will create comparative groups. These comparative groups will be then analyzed with the help of control group. The experimental studies are designed in a way to generate the data about the causality through comparative and control group. In simplest experiment one or more measurements are taken on all subjects before and after the treatment. Whereas in Single-subject design a special case , the, measurements are taken repeatedly (e.g. 10 times) before and after the intervention on one or few subjects.
Experimental designs are set up to allow the greatest amount of control possible so that causality may be examined closely. The three important elements of the Experimental design are Manipulation, Control and Randomization. Hence the quantitative research is good method of research for generating the objective results, testing the theory and hypothesis and plays and important role in narrowing down the research work.
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