Qualitative data
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More on reddit.comELI5 What is qualitative research method and how does it ensures the reliability and validity of its method?
Qualitative research differs from quantitative research in that it has less to do with numbers and more with opinions.
For example, if you were testing a new drug, you may do a qualitative analysis on how people feel, by giving them questionnaires and asking them about how they feel using the drug. It's impossible to quantify a person's emotions, hence why we use qualitative.
Reliability is mainly to due with how many times you did the procedure. So, asking 2 people won't give very reliable results, but asking 10,000 will give more reliable results.
Validity has to do with the testing method you use. So asking people different questions at different periods after using the drug is not very valid, it'd more valid to ask the same set of questions at the same time after every dosage.
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