Table I.

Results of excluded and included studies for meta-analysis.

First author	Year	Statistical significance	Power*	Severity Index†	Reason of exclusion	Description of results
Studies which were excluded from meta-analysis
Sirveaux	2004	+	67.2	0.36	No specific data was presented	“The presence of the notch significantly affected the Constant score when the notch was either over the screw or extensive (p < 0.05).”
Werner	2005	+	16.9	0.84	No specific data was presented	“Inferior notching negatively correlated with the Constant score (r = 0.3184; p = 0.0311).”
Boileau	2006	-	49.4	0.22	No specific data was presented	”Neither the presence nor the size of the notch had a negative effect on the Constant score, the adjusted Constant score, or the ASES score.”
Stechel	2010	-	36.4	0.06	No specific data was presented	“There were no statistically significant differences between the groups. No effect on the Constant score could be seen."
Sadoghi	2011	+	18.8	0.20	No specific data was presented	"We did not find any significant correlations at mid-term follow-up, ranging from 24 to 60 months. In long-term follow-up (60 months and more), we found significant positive correlations between infraglenoidal notching and the Constant pain score (p = 0.3), and active anteversion (p < 0.01) and active external rotation (p < 0.01).”
Sershon	2014	+	29.1	0.00	No specific data was presented	“There was no correlation between preoperative or postoperative radiological findings and clinical outcomes.”
Athwal	2015	-	45.6	0.05	Risk of selection bias due to study design	"There was no significant differences with respect to range of movement (p > .491) or functional scores (p > .556).”
Torrens	2016	-	66.9	0.63	Risk of selection bias due to study design	“Scapular notching did not significantly affect the total Constant score or range of movement.”
Erbstbbrunner	2017	+	19.4	0.43	Difference in grouping of comparison	“Patients with scapular notching of grade 2 or higher (n = 10) had a significantly lower mean relative Constant score (57% vs 81%; p = 0.006) ... at the time of final follow-up compared with patients with no or grade-1 notching (n = 11).”
Kirzner	2018	+	46.2	0.05	Risk of selection bias due to study design	”Statistically significant differences could be seen; however, when comparing ASES, SSV, WOOS and pain scores between the two groups with the notching cohort showing worse outcomes.”
Pastor	2018	+	50.7	0.09	No specific data was presented	“Inferior notching negatively correlated with the Constant score (r = 0.3184; p = 0.0311). However, the Constant score did not significantly differ between each grade of notching.”
Torrens	2019	-	62.3	0.05	Risk of selection bias due to study design	”The functional outcomes (Constant scores) were not significantly different between patients with and without a scapular notch.”
Studies which were included in meta-analysis
Simovitch	2007	+	69.6	0.70		Results are reflected in meta-analysis
Levigne	2008	-	99.7	0.53		Results are reflected in meta-analysis
Favard	2011	-	34.2	1.25		Results are reflected in meta-analysis
Levigne	2011	-	99.9	0.51		Results are reflected in meta-analysis
Mizuno	2012	-	50.4	0.06		Results are reflected in meta-analysis
Torrens	2013	-	40.8	0.29		Results are reflected in meta-analysis
Birgorre	2014	-	85.2	0.05		Results are reflected in meta-analysis
Feeley	2014	-	49.2	0.14		Results are reflected in meta-analysis
Katz	2015	-	84.9	0.05		Results are reflected in meta-analysis
Mollon	2017	+	94.9	0.09		Results are reflected in meta-analysis
Simovitch	2019	+	93.5	0.21		Results are reflected in meta-analysis

^*Statistical power was calculated from a one-tail test using an α = 0.05. As some of studies did not report any functional score on each study group, we calculated the study power using the mean of the Constant-Murley score (CMS) for each study and assumed a difference in CMS of 5 points and also assumed standard deviation of ten points for each group as Mollon et al.²⁵

^†The severity index were defined as notching grade 3 + 4 divided by grade 1 + 2 by Nerot-Sirveaux classification.¹⁴