{HEAD ~ The administrator database} and {TAIL ~ the one or more investigator databases} are communicatively connected to the centralized secure database 
{ HEAD ~ The administrator database } and { TAIL ~ the one or more investigator databases } are communicatively connected to the centralized secure database
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH