Table 1.

Search strategy for retrieval of relevant articles from multiple databases

Database	Search strategy
MEDLINE (n = 106)	1. exp Suicide/
	2. suicid*.mp.
	3. exp Self-Injurious Behavior/
	4. (self harm* or self inflict* or self injur* or self wound* or self mutilat*).mp.
	5. automutilat*.mp
	6. 1 or 2 or 3 or 4 or 5
	7. brain derived neurotrophic factor.mp. or Brain-Derived Neurotrophic Factor/
	8. bdnf.mp
	9. 7 or 8
	10. 6 and 9
EMBASE (n = 366)	1. exp suicidal behaviour/
	2. suicid*.mp.
	3. exp automutilation/
	4. (self harm* or self inflict* or self wound* or self mutilat* or autmutilat*).mp.
	5. 1 or 2 or 3 or 4
	6. brain derived neurotrophic factor.mp. or exp brain derived neurotrophic factor/
	7. bdnf.mp.
	8. 6 or 7
	9. 5 and 8
PsycINFO (n = 76)	1. exp Suicide/
	2. exp Attempted Suicide/
	3. exp Suicidal Ideation/
	4. suicide*.mp
	5. exp Self Injurious Behavior/
	6. (self harm* self injur* or self inflict* or self wound* or self mutilat* or autmutilat*).mp.
	7. 1 or 2 or 3 or 4 or 5 or 6
	8. brain derived neurotrophic factor.mp. or exp Brain Derived Neurotrophic Factor/
	9. bdnf.mp.
	10. 8 or 9
	11. 7 and 10
CINAHL (n = 4)	1. MH (“Suicide+”)
	2. “suicid*”
	3. MH (“Self-Injurious Behavior”)
	4. “self harm*” OR “self injur*” OR “self inflict*” OR “self wound*” OR “self mutilat*” OR “automutil*”
	5. 1 or 2 or 3 or 4
	6. “brain derived neurotrophic factor”
	7. “bdnf”
	8. 6 or 7
	9. 5 and 8

CINAHL, Cumulative Index to Nursing and Allied Health Literature; EMBASE, Excerpta Medica Database.