Table 1. Primary spontaneous pneumomediastinum demographics.

Study	Mean age	Age range	N	Female	Male
Abolnik et al. 1991	18.8	8–31	25	4	21
Kaneki et al. 2000	NR	13–27	33	7	26
Gerazounis et al. 2003	NR	12–32	22	4	18
Jougon et al. 2003	25	16–46	12	1	11
Koullias et al. 2004	17.5	15–26	24	6	18
Weissberg & Weissberg 2004	NR	15–37	22	10	12
Campillo-Soto et al. 2005	36.8	11–90	36	11	25
Newcomb & Clarke 2005	NR	11–58	18	4	14
Freixinet et al. 2005	21.4	14–36	32	8	24
Macia et al. 2007	21	14–35	41	7	34
Mondello et al. 2007	25	18–33	18	8	10
Caceres et al. 2008	27	3–71	28	12	16
Al-Mufarrej et al. 2008	25.5	19–39	17	6	11
Takada et al. 2008	20.1	13–28	25	7	18
Perna et al. 2010	27.3	16–42	47	14	33
Ryoo 2012	18.3	10–38	32	7	25
Okada et al. 2014	22	13–41	20	1	19
Bakhos et al. 2014	19	5–57	49	23	26
Ebina et al. 2017	19.7	5–36	34	8	26
SUM			535	148	387
AVE ± std dev [n, studies]	23±5 [19]		28.2±10 [19]
Percent				28	72