Advantages and Disadvantages of Research Methods

They never really ask for more than two advantages or disadvantages at a time, learn about three of each just to be safe. This part is easy to bullshit your way through though. 

Interviews:

Communication Studies doesn't really make a fuss about whether it's structured or unstructured interviews. So feel free to generalize. 

• Advantages:
• provides detailed responses
• provides clear context to questions
• provides subjects point of view
• interview can observe non-verbal behaviour
• higher response rate
• invites discussion

• Disadvantages:
• Time consuming 
• Difficult to analyse
• No statistical inference
• opportunity for interviewer bias to intervene 

Questionnaires:

Same goes for questionnaires.... it doesn't matter if it's open or close ended.

• Advantages:
• large target audience
• statistical analysis
• responses are anonymous 
• easy to organize data
• cost effective
• trends can be identified by asking the same question over time

• Disadvantages:
• Incomplete answers
• respondents may misinterpret information
• low response rates may be received
• respondents are not always honest in their answers
• doesn't account for illiteracy among respondents 

Observation:

Doesn't matter if it's covert or overt participant observation

• Advantages:
• produces detailed understanding of situation/processes 
• direct contact with respondents 
• very useful for studying behavioural patterns

• Disadvantages:
• can be time consuming 
• analyses can be complicated
• participant's behaviour may be altered since they know they're being watched (Hawthorne effect)
• Observer bias
• observers may become distracted or attached to their subject (trying to give advice and crazy shit like that)

Scientific Testing:

• Advantages:
• very accurate findings
• reliable 

• Disadvantages:
• results may vary depending on time 
• sample size may be too small 
• human error (we fuck up sometimes)

There are more methods (surveys, focus groups etc.) but those listed above are the main ones. They usually ask for two methods (I recommend focusing on questionnaires and interviews)