Scientific skills are available to all human players; they cost 75 XP for Scientists, 100 XP for civilians and 150 XP for military personnel.
List of Scientific skills
Important: Diagnosis does NOT detect infections.
DNA extraction is a good XP source for non-combat-oriented players. NT Lab Assistants start with the DNA extractor; others need to search in an NT building until they find one. The NecroNet Access skill allows you to view all zombies scanned this way within powered Necrotech Buildings. It will display all the data in a 9x9 area around where the Necrotech Building is. Since the NecroNet only surrounds NecroTech buildings, NecroNet coverage is not city-wide. The following map shows the maximum coverage as an orange overlay:
You can also spend 20 AP to create a syringe using materials in the lab. It has been verified that you can also revive Brain Rotted zombies that enter or break through the barricades on a powered Necrotech Building by use of your NecroNet Access to the labs.
The most useful skill for beginning healers is actually Diagnosis, not First Aid, since it prevents wastage of time trying to heal fully-healthy characters. The First Aid skill reduces the amount of XP available to be earned by healing, since it increases the amount of HP healed without increasing the XP earned per use. Because it reduces the number of FAKs and AP needed by half, however, it can be very useful for higher level players in organised groups, or for keeping your own character alive. If you want to completely roleplay your class, the Surgery skill is very useful. With only one FAK and one action point you can heal 15 HP in one go. The downside is that you can only do this in a hospital with a fueled generator.
Diagnosis has become somewhat infamous as a skill used by PK survivor players because it allows for someone to easily spot a wounded player and finish him or her off.
Diagnosis carries over to zombies and works equivalently to the Scent Blood skill. Zombies who find themselves revived can purchase Diagnosis for 100 XP rather than spending 200 XP for Scent Fear and then Scent Blood. Scent fear still must be purchased at a later stage to access the rest of the Scent tree.