How strong is the relationship between caregiver speech and language development? A meta-analysis

Area of Science:

• Developmental Psychology
• Linguistics
• Child Language Acquisition

Background:

• Previous research indicates a positive link between early language exposure and child language development.
• Significant heterogeneity exists in study designs, potentially impacting the reliability of findings.
• Existing meta-analyses may not fully capture the breadth of recent research or diverse populations.

Purpose of the Study:

• To conduct a comprehensive meta-analysis on the association between early language input and child language outcomes.
• To include recent studies, non-English speaking populations, and varied input measures.
• To examine potential moderators and utilize a multilevel model for robust analysis.

Main Methods:

• Meta-analysis of 71 studies with 4760 participants.
• Inclusion of recent and non-English studies.
• Categorization of input measures and application of a multilevel model.
• Analysis of moderators such as child age and study duration.

Main Results:

• A moderate association (R²=0.04-0.07) was found between language input and child language outcomes.
• No significant differences in effect size were observed across different input measures.
• Evidence of publication bias was noted.
• Child age and study duration moderated the input-outcome association.

Conclusions:

• The association between early language input and child language outcomes is robust yet modest.
• Findings are consistent across various contexts and measurement approaches.
• Further research should consider the nuances of input quality and quantity in diverse populations.