Complex sentence: However, the scientists were not yet able to figure out all of the exact health problems that are associated with PTSD because most of the health problems that are related to PTSD are self-reposted.
Split into simpler sentences: However, the scientists were not yet able to figure out all of the exact health problems that are associated with PTSD. This happens because most of the health problems that are related to PTSD are self-reposted.