Title: Different Research Methods: Strengths and Weaknesses — The Learning Scientists
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Content: Weaknesses: We cannot determine a cause and effect relationship from descriptive research. For example, if a student talks about engaging with a particular learning strategy, and then provides an in-depth account of why they think it helped them learn, we cannot conclude that this strategy actually did help the student learn. We also have to be very careful of reactivity in this type of research. Sometimes, people (and animals too) change their behavior if they know they're being observed. Similarly, in surveys we have to worry about participants providing responses that are considered desirable or in line with social norms. ( For example, if a parent is asked, "did you ever smoke while pregnant with your child?" we have to worry about parents saying "no, never" because that is the more desirable answer, or the one that aligns with social norms.) Correlational Research
Correlational studies involve measuring two or more variables. For that reason, this research is inherently quantitative.