Data Management To ensure correct entrance of data from the CRF to the database which will be used for statistical analyses, a special database program called OpenClinica© (Community Edition, v3.1.2, OpenClinica©, LLC, Waltham, MA, USA) will be used. A study environment will be build, containing the specific visits and necessary data entry fields. Electronic-CRFs (eCRF) will be made, similar to the hardcopy CRFs. These eCRFs will be enhanced by safeguards and queries to warrant correct entry of data. The investigator, or his/her designated representative, will enter all data from the hardcopy printed CRF on the eCRFs, which automatically stores the data in the database. All changes made to the database will be logged ('audit trail'), which is required by GCP. On a regular basis all data from the OpenClinica©-database will be extracted to an Excel-file for backup purposes.