“…Ten studies identified a single inflection point around which performance significantly changed, suggesting a bi-phasic learning curve [7,10,15,17,19,21,25,27,28,30]. Eight studies identified two inflection points around which performance significantly changed, suggesting a tri-or multi-phasic learning curve [8,11,13,20,24,29,31,32]. The remaining 4 studies explored multiple parameters to explore the learning curve and found bi-phasic and multi-phasic learning curves depending on which parameter was examined [9,16,18,22].…”