Table 3.

Subgroup analyses for the difference of pitch standard deviation between ASD and TD groups. The elicitation tasks and the age of participants were confounding factors.

	Pooled SMD	Heterogeneity (%)	p-value
Confounding factor
Task type
Narration	− 0.14 (95% CI [− 1.14, 0.85])	82.6	< 0.001
Conversation	− 0.16 (95% CI [− 0.75, 0.42])	43.7	0.169
Focus	− 0.11 (95% CI [− 1.11, 0.89])	92.1	< 0.001
Crying	0.56 (95% CI [− 0.68, 1.80])	58.0	0.123
Age of ASD participants
Infancy (age ≤ 2)	0.21 (95% CI [− 0.54, 0.96])	65.2	0.023
Childhood (age: 2–11)	− 0.05 (95% CI [− 0.87, 0.76])	90.8	< 0.001