Table 2.

Spearman correlation analysis between SCFA and microbial richness. Spearman’s rank tests calculated the correlation coefficients between SCFA and microbial richness, including Faith_pd and observed OTUs. The results with significant correlation (p < 0.05) are presented as an asterisk mark.

Group		Total (N = 92)			ASD (N = 54)			TDC (N = 38)
Relative SCFA		AA	PA	BA	AA	PA	BA	AA	PA	BA
Faith_pd	rs	−0.185	0.000	0.318	−0.006	−0.188	0.216	−0.428	0.264	0.490
	p	0.078	0.997	0.002 *	0.964	0.174	0.117	0.008 *	0.110	0.002 *
Observed OTUs	rs	−0.101	−0.011	0.253	0.083	−0.154	0.103	−0.319	0.169	0.438
	p	0.340	0.917	0.015 *	0.551	0.267	0.457	0.051	0.310	0.006 *

ASD, autism spectrum disorder; TDC, typical developing children; SCFA, short-chain fatty acid; AA, acetic acid; PA, propionic acid; BA, butyric acid. r_s indicates correlation coefficient, * p < 0.05.