Closed Questions:
Closed questions structure the answer by only allowing responses which fit into pre-decided categories. Data that can be placed into a category is called nominal data. Closed questions can also provide ordinal data (which can be ranked).
They can be economical. The respondent provides information which can be easily converted into quantitative data. The questions are standardized.
They lack detail. Because the responses are fixed, there is less scope for respondents to supply answers which reflect their true feelings on a topic.
Open Questions:
Open questions allow people to express what they think in their own words. Open-ended questions enabled the respondents to answer in as much details as they like in their own words. Often used for complex questions that cannot be answered in a few simple categories but require more detail and discussion.
Rich qualitative data is obtained as open questions allow the respondent to elaborate their answer. This means the research can find out why a person holds a certain attitude.
Time-consuming to collect the data. Time-consuming to analyze the data. Not suitable for less-educated respondents as open questions require superior writing skills and a better ability to express one’s feelings verbally.
