Supplementary Table 1. Full electronic search strategy for Ovid Medline database, used in the current systematic review and meta-analysis. The full electronic search strategy is provided for at least one database, as per point #8 from the PRISMA 2009 Checklist.
1 / “Spine” [MeSH] OR “back” [MeSH] OR “lumbar” OR “vertebra*”OR “Radiculopathy” [MeSH] OR “Spinal Stenosis” [MeSH] OR “Spondylolisthesis” [MeSH] OR “Intervertebral Disc Degeneration” [MeSH] OR “intervertebral disc disease”2 / “Spinal Fusion” [MeSH] OR “fusion” OR “transforaminal lumbar fusion” OR “transforaminal lumbar interbody fusion” OR “TLIF”
3 / “Percutaneous” [MeSH] OR “Surgical Procedures, Minimally Invasive” [MeSH] OR “minimally invasive” OR “minimal surgery” OR “minimal access” OR (minimal* AND invasive) OR (minimal* AND surg*) OR (minimal* AND access*)
4 / #1 AND #2 AND #3
Supplementary Table 2. Quality appraisal of included studies using a critical review checklist of the Dutch Cochrane Centre proposed by MOOSE (Stroup DF, Berlin JA, Morton SC, et al. Meta-analysis of observational studies in epidemiology: a proposal for reporting. Meta-analysis Of Observational Studies in Epidemiology (MOOSE) group. JAMA 2000;283:2008-12.0).
Study / Clear definition of study population / Clear definition of outcomes and outcome assessment / Independent assessment of outcome parameters / Sufficient duration of follow-up / No selective loss during follow-up? / Important confounders and prognostic factors identified?Wong et al, 2014 / No / Yes / Yes / No / Yes / Yes
Tian et al, 2014 / Yes / Yes / Yes / Yes / Yes / Yes
Sulaiman et al, 2014 / Yes / Yes / Yes / Yes / Yes / No
Singh et al, 2014 / Yes / Yes / Yes / No / Yes / Yes
Parker et al, 2014 / Yes / Yes / Yes / Yes / Yes / Yes
Lo et al, 2014 / Yes / Yes / Yes / No / Yes / No
Gu et al, 2014 / Yes / Yes / Yes / Yes / Yes / No
Zairi et al, 2013 / Yes / Yes / Yes / Yes / Yes / Yes
Seng et al, 2013 / Yes / Yes / Yes / Yes / Yes / Yes
Rodriguez-Vela et al, 2013 / Yes / Yes / Yes / Yes / Yes / Yes
Lau et al, 2013 / Yes / Yes / Yes / No / Yes / Yes
Cheng et al, 2013 / Yes / Yes / Yes / No / Yes / No
Brodano et al, 2013 / Yes / Yes / Yes / Yes / Yes / No
Archavlis et al, 2013 / Yes / Yes / Yes / Yes / Yes / No
Mobbs et al, 2012 / Yes / Yes / Yes / No / Yes / Yes
Wang, H et al, 2011 / Yes / Yes / Yes / Yes / Yes / No
Wang, J, et al 2000 / Yes / Yes / Yes / Yes / Yes / No
Villavicencio et al, 2010 / Yes / Yes / Yes / No / Yes / Yes
Shunwu et al, 2010 / Yes / Yes / Yes / Yes / Yes / Yes
Schizas et al, 2009 / Yes / Yes / Yes / Yes / Yes / Yes
Schuefler et al, 2007 / Yes / Yes / Yes / No / Yes / Yes