Choosing between qualitative and quantitative research design

A research design is basically how you conduct your research and find answers to the identified questions.

A research design should primarily suit your research objectives. Nothing but your research questions and the expected answers can determine your choice of research design.

The following explanation will give you a clarification on what each method implies :-

Quantitative research design: the research design aims to define variables or depict relationships between variables in quantifiable or numeric terms. Relationships may be expressed with statistics like correlation, mean, standard deviation, etc. depending upon the aim, quantitative research can assume three forms:

• Descriptive research: numerically describe a phenomenon

• Correlational research: numerically express the relationship among variables

• Experimental research: manipulate variables to test cause and effect.

• Qualitative research design: This is a systematic subjective approach to describe phenomena and give them meaning. It aims to analyse and convey how a phenomenon of interest is understood, interpreted, produced or constituted. It employs analytical methods that are sensitive to context, complexity and detail.
Qualitative method entails analysis of case studies, perceptions, narratives and the like.

I hope this helps fellow researchers in understanding the basic difference between the two designs. you can alternatively use a combination of both.

I will be happy to entertain other confusions in this context!