Public Surveys vs. Private Surveys

Would you like to leave your survey public or would you rather make it private? SurveyShare explains the four different levels of accessibility to choose from:

Public
For a public survey, anyone who knows the web address (URL) of the survey may respond to it. Although each respondent is asked to enter an email address, a respondent could conceivably take the survey multiple times by entering different email addresses.
Private
For a private survey, only those people whom you specify (via the Address Management page) may take the survey. When a respondent begins a survey, they are asked to input an email address. If this email address matches one of the email addresses that you have associated with the survey, they are allowed to take the survey once, and only once.
Anonymous Unsecured
For an anonymous unsecured survey, anyone who knows the web address (URL) of the survey may respond to it. No identifying information is required to take the survey, which means a respondent could conceivably take the survey multiple times.
Password
For a password protected survey, only those people who know the survey password you specify and the web address (URL) will be allowed to take the survey. A password may be up to twenty characters in length and should consist solely of alphanumeric characters, e.g. A-Z, a-z, and 0-9.

Whichever type you choose, rest assured that all respondent data remain truly anonymous in the sense that you will not be able tie an individual's data to a particular response set (assuming you have not asked for personal identifiers within the survey). However, if you are using the survey to conduct research for publication and/or wish to identify or link respondents to their actual responses, you should first check with the UNC Charlotte Institutional Review Board for Research with Human Subjects to ensure that your study is exempt from review.