“…Full text and images were not available Excluded (Özahi et al, 2002;Padovani et al, 1982;Surka et al, 1999) Information insufficient to judge the phenotype (insufficient description, unclear image, no full-chest image, no information on the survival length) Excluded (Blaas et al, 1993;Farriaux & Poupard, 1978;Feldman & Heyman, 1987;Kang et al, 1992;Morin et al, 2001;Tanyeri et al, 2018;Winter & Bloom, 1999) Causal mutations in other genes than SNRPB and hence not diagnosed as CCMS Excluded (Legare et al, 2017;Zeevaert et al, 2009) Costovertebral joint defects without rib gap Excluded (Neelam & Sudhir, 2021) No ribs or underdeveloped ribs in the fetus/too young gestational stage/ premature birth Excluded (Fidalgo-Alvarez et al, 1988;Hennekam & Goldschmeding, 1998;Ibba et al, 1997;Kirk et al, 1999;Lale et al, 2011;Megier et al, 1998;Sahyoun et al, 1998;Song et al, 1993) Reporting follow-up only/follow-up cases and new cases without sufficient information Excluded (Doyle, 1969;Schrander-Stumpel et al, 1996;van den Ende et al, 1998) Analyzed in this study (90 cases in 60 papers in total)…”