Fig. 2
From: Impact of quality certification of multidisciplinary head and neck tumor centers
Comparison of intervention and stay duration from 2008–2012 to 2013–2017. a–d, f Hours of surgery, days at the intensive care unit, hours of mechanical ventilation, total amount of transfused blood products (milliliter) and the difference between actual and predetermined days of stay were test nonparametric with Mann-Whitney U test. e Comparison of average and actual stay were test parametric with one-way ANOVA with post-hoc Tukey for multiple comparisons. Data are shown as mean ± SEM