Table 2.

Comparison^a of the RRPS overall prevalence between the four studied indigenous groups

Ethnical group:	Subjects with RRPS	Prevalence (%)	95 % CIb
Chontal (n = 124)	19	15.32	10.03–22.69
Maya-Yucateco (n = 1523)	165	10.83	9.37–12.49
Qom (n = 1656)	48	2.90	2.19–3.82
Mixteco (n = 937)	7	0.75	0.36–1.53

^a X ² results: Chontal vs. Maya: p = 0.18; Chontal vs. Qom: p < 0.0001; Chontal vs. Mixteco: p < 0.0001; Mava vs. Qom: p < 0.0001; Maya vs. Mixteco: p < 0.0001; Qom vs. Mixteco: p < 0.0001

^bPrevalence’s 95 % confidence interval