Our research proposal is related to healthy eating and obesity. Assume, we want to provide a qualitative research to understand how the level of healthiness of food consumed is related to the people’s constitution (normal weight or obesity).
The next step is data collection. There are several basic methods to collect the data – observations, interviewing, focus groups, etc. For our case we have to use both observations and interviewing. To collect the data we have to observe a number of humans (for example, those, who are undergoing periodic medical examination in a clinic), measuring their body mass and height. Also we should provide an interviewing for each person observed – to understand the level of healthiness of their daily ration. The level of healthiness is determined by researcher based on his own estimation.
As a result we obtain a number of observations with the following variables: body mass, level of healthiness of food, height. It is time to formulate a hypothesis and check it using some quantitative methods. First of all we calculate the BMI for each observation. Then, divide data set on two groups by BMI – those, who have normal or less BMI (< 25) and those, who have tendencies to obesity (> 25). After this, we have to compare mean values of Level of Healthiness of Food (LHF) for these two groups, checking the hypothesis, that “those who have tendencies to obesity have significantly lower LHF than those, who have weight no bigger than normal”.
We can perform independent two-sample Student’s t-test to compare means. The results of testing will show us if we were right or wrong
The advantages of this method:
- We can check our hypothesis with the level of reliability given beforehand.
- The combination of qualitative and quantitative researches gives the better understanding of situation
- There might be needed to collect an additional data to understand if there any other issues which have impact on BMI (for example, diseases, level of activity, etc.)
- Interviewing about the daily ration could consist some errors because of insincerity of respondents and subjective opinion of researcher when evaluating the LHF.
Creswell, J. W. (2003). Research design: Qualitative, quantitative, and mixed method approaches. Thousand Oaks, CA: Sage Publications.