Table 8 Friedman test (nonparametric) of Hospital Case numbers of TKA over time with Post-Hoc-Tests

From: Impact of suspending minimum volume requirements for knee arthroplasty on hospitals in Germany: an uncontrolled before–after study

  Friedman test Post-hoc-tests (Dunn-Bonferroni-Test) with Bonferroni-correction
N Mean SD Mean rank Sig. 2006 2008 2010 2012 2013 2014
2006 1055 114.41 125,58 3,10 0,000 x      
2008 1055 134,33 139,28 4,08 < 0.001 x     
2010 1055 133,52 135,30 4,10 < 0.001 1.000 x    
2012 1055 120,76 123,68 3,48 < 0.001 < 0.001 < 0.001 x   
2013 1055 114,82 123,31 3,00 1.000 < 0.001 < 0.001 < 0.001 x  
2014 1055 118,05 128,60 3,24 1.000 < 0.001 < 0.001 .037 .050 x