The choice of methodology depends on the ontology and epistemology
Methodology here refers to a general framework for doing research, within which there may be multiple specific methods
A realist ontology and rationalist/positivist epistemology leads to scientific methodology, and the use of experiments
A constructionist ontology and relativist/critical realist epidemiology leads to the use of ‘NEW PARADIGM'
Pie de foto: : You have to choose what ontology and epistemology you will adopt for a given topic. Then you can decide what methodology to use, and begin designing a study.