“…A number of authors [2][3][4]7,10,11,[13][14][15]17,19,21,22,25,26,[28][29][30][31][34][35][36][37][38][39][40] have measured Haller's index or pectus severity index (PSI) as part of their preoperative assessment. Although a PSI of >3.2 was used as an inclusion criterion for MIRPE in some reports, in some of these, the authors admitted that they had performed MIRPE upon patients with a PSI of <3.2 [4,11,13,14,17,25,28,30,36,38,27,39].…”