Look here for answers to some commonly asked questions.    

What is the best time of year to survey students?
How do I know if my survey is too long?
How many students should I survey? 
Should your scale have a midpoint? How many response options should there be?

What is the best time of year to survey students?   
The answer depends on both the purpose of your survey and the cycle of other university surveys. For example, if you want to ask freshmen about their experiences at DePaul, then you want to make sure they have had enough time to have experiences - waiting until spring term is better than surveying freshmen in the fall. However, there may be other university surveys, like the DePaul Student Satisfaction Survey, that are sent out in the spring. Consult the Survey Calendar on this website or contact Joe Filkins for more information.
 
How do I know if my survey is too long?   
No one has ever complained of a survey being too short! You want to ask enough questions to address your topic, but not too many to exhaust your respondents - this is what we call "survey fatigue." We recommend that a typical survey take no longer than 10 minutes to complete. Have someone not involved in your project answer the survey to test the length.
 
How many students should I survey?   
This boils down to how you plan to analyze the data and what subgroups you will want to consider, along with an estimate of what fraction of the population falls into those subgroups.  Most sample size decisions are concentrated on the minimum sample sizes that can be tolerated for the smallest subgroups of importance. 
 
Should your scale have a midpoint?  How many response options should there be?   
There are no absolute answers to these questions.  Some prefer the use of a four-point scale (i.e., Strongly Agree, Agree, Disagree, Strongly Disagree) to force the respondent to make a choice, rather than to give them the "neutral" option that a five point scale would include.  While some have found a decrease in socially desireable responses using the four point format, others have found an increase in the reliability and validity of the questions when using a five or seven point format. 
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