CHFD	Cochin hand functional disability
DN4	Doleur Neuropatique 4
SRs	Evidence-based guideline for Peer Review of Electronic Search Strategies (PRESS) for systematic reviews
FAAH	Fatty acid amide hydrolase
GOfER	Graphical Overview for Evidence Reviews diagram
PROSPERO	International prospective register of systematic reviews
LBP-IQ	Low Back Pain Impact Questionnaire
MeSH	Medical and subject headings
MNSI	Michigan Neuropathy Screening Instrument
NIHR	National Institute for Health Research
NPQ	Neuropathic Pain Questionnaire
NPSI	Neuropathic pain symptom inventory
NRSI	Nonrandomized studies of the effects of interventions
NF-kB	Nuclear factor kB
PPAR-α	Nuclear receptor peroxisome proliferator-activated receptor-α
NRS	Numeric rating scale
ODQ	Oswestry Disability Questionnaire
PEA	Palmitoylethanolamide
PICOS	Participants, intervention, control, outcome, study design
PRISMA	Preferred Reporting Items for Systematic Reviews and Meta-Analyses
RCTs	Randomized clinical trials
RoB	Risk of bias
ROBINS-I	Risk Of Bias In Non-randomised Studies of Interventions tool
TRPV1	Transient receptor potential channel of the vanilloid type 1
PEA-um	Ultramicronized PEA
VAS	Visual analogue scale
WOS	Web of Science