Table 2 Assessment of surgeon volume-outcomes relationship

Colorectal cancer

++

Archampong et al. 2012 [24]

9/2011

Results are significantly better for HVS concerning mortality, overall survival, permanent stoma, and abdominoperineal excision; not significant for disease-specific survival and anastomotic leak

Archampong et al. 2010 [25]

3/2010

Results are significantly better for HVS concerning overall survival, permanent stoma, abdominoperineal excision, and local recurrence; not significant for mortality and anastomotic leak

Van Gijn et al. 2010 [48]

2/2010

Data clearly support a relation between surgeon volume and mortality as well as survival

Salz et al. 2008 [43]

4/2007

No overall conclusions can be made due to heterogeneous study results and flaws in the methodological quality of the systematic review

Iversen et al. 2007 (short-term) [35]

6/2004

Data indicate a relation between volume and short-term mortality for colon cancer but no statistically significant results for colorectal and rectal cancer

Iversen et al. 2007 (long-term) [36]

6/2004

Data indicate a relation between volume and long-term survival for colon cancer but no statistically significant results for colorectal and rectal cancer

Bariatric surgery

++

Zevin et al. 2012 [54]

4/2011

Data clearly support the relationship between HVS and several patient-related outcomes including mortality

Padwal et al. 2011 [41]

1/2011

Data clearly support the relationship between HVS and several patient-related outcomes including mortality

Klarenbach et al. 2010 [37]

2/2009

Data clearly support the relationship between HVS and several patient-related outcomes including mortality

AAA

+

Young et al. 2007 [53]

NR

Pooled effect sizes for mortality were significant but findings should be interpreted with caution due to the quality of the data

Wilt et al. 2006 [50]

10/2005

Data clearly support the relationship between HVS and in-hospital mortality

Esophageal cancer

+

Brusselaers et al. 2014 [26]

9/2013

Data indicate a relationship between volume and long-term survival

Wouters et al. 2012 [52]

7/2010

No significant results for patient-related outcomes albeit data indicate a slight relationship between volume and mortality as well as survival

Radical prostatectomy

+

Trinh et al. 2013 [47]

12/2011

Data indicate a relation between volume and lots of different patient-related outcomes albeit there are no clear results for mortality

Wilt et al. 2008 [51]

11/2007

Data indicate a relation between volume and different complications albeit the result for mortality is not significant

Total knee arthroplasty

+

Lau et al. 2012 [38]

12/2011

Data indicate a relation between volume and many different patient-related outcomes but results are significant only for about the half of the outcomes

Stengel et al. 2004 [45]

NR

Data do not support a significant relationship between surgeon volume and patient-related outcomes albeit most outcomes are better for HVS

Breast cancer

++

Gooiker et al. 2010 [30]

2/2010

Data of this methodologically excellent review clearly support the relationship between HVS and survival

CABG

?

Sepehripour et al. 2013 [44]

7/2012

Data do not indicate a clear relation between volume and mortality or other patient-related outcomes and results should be interpreted with caution due to methodological shortcomings

Cystectomy

+

Goossens-Laan et al. 2011 [32]

9/2010

Data show a significant relation between volume and mortality whereas the result for survival is not significant and the body of evidence is limited

Head and neck cancer

+

Eskander et al. 2014 [28]

3/2013

Data indicate a relationship for volume and long-term mortality/survival for surgery of the oral cavity but no significant results for in-hospital mortality for larynx or oropharyngeal surgery

Lung cancer

+

Van Meyenfeldt et al. 2012 [49]

1/2011

Data show a relationship between surgeon volume and postoperative mortality

Norwood procedure

?

Pieper et al. 2014 [42]

3/2013

Data might indicate a slight relationship between volume and patient-related outcomes but the results are heterogeneous and predominantly non-significant

Pancreatic surgery

+

Gooiker et al. 2011 [31]

2/2010

Data indicate a relation between volume and postoperative mortality albeit studies are heterogeneous

PCI

?

Strom et al. 2014 [46]

9/2012

Data indicate a relation between volume and major adverse cardiac events but there is no relationship between volume and mortality and pooled results are very heterogeneous

Trauma

?

Caputo et al. 2014 [27]

6/2013

The review included only four primary studies which are more than 10 years old and it does not report on statistical significance