Removing names of people is a first priority. This includes personal names, nicknames and potentially pseudonames. Data lives online potentially forever so protecting your reporters is important.
Personal phone numbers for SMS or tracking reports should be removed. These should not be publicly displayed on a website. If you are including SMS reports in your project, remove these before publishing your reports.
There is a wide range of sensitive details about a report that you may want to consider removing. For example, for the Uchaguzi - Kenyan Elections 2013 project, we removed tribal names. The reason we did this was to not incite dangerous speech. We worked in partnership with Ihub Research considering their Umati (Monitoring Dangerous Speech project).
There will be cases where the exact geolocation of a report needs to be altered. This is for the safety of the topic. For example, if you are mapping an incident in a conflict zone. Consider not having the exact location but instead of general region.
Standby Task Force: Data Protection Standards 2.0
ICT4Peace - The potential and Challenges of Open Data for Crisis Information Management and Aid Efficiency
Oxfam: Evolution of Protection of Civilians in Armed Conflict
UNOCHA - Humanitarianism in a Network Age
Woodrow Wilson Center: Privacy and Missing Persons after Natural Disasters