Positivists prefer scientific, quantifiable data that is quick and easy to obtain, and is rich in reliability and validity.
Interpretivists, on the other hand, value qualitative data that provides in-depth meaning of a small-scale research group, and is therefore rich in validity.
Examples of practical issues
Time- Some methods take more time than others because of, for example, more detailed data being recorded. Research methods that take more time may lead to a smaller research sample size
Money- The money available to conduct the research affects the number of researchers, respondents and amount of research time. Equipment,travel and people's time are often not cheap.
Access- Some groups of respondents and location are easier to access than others. For example, to enter a school to do research, permission is required.
Examples of ethical issues
Informedconsent- Researchers should have the informed consent of their research subjects, because of the effects that the research may have on them.
Confidentiality- Research subjects have a right to anonymity, so they should not be identifiable when the research is published.
Psychologicalharm- Some research groups are more vulnerable to psychological harm than others (eg. children).
What is required for a research method to be reliable?