Table 1. Summary of findings for main outcomes (Analysis I: Random effects model, 14 studies).
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect | Number of Participants | Quality of evidence | Comments | |
|---|---|---|---|---|---|---|
| (95% CI) | (studies) | (GRADE) | ||||
| Assumed risk | Corresponding risk | |||||
| Control | Autism general symptoms | |||||
| Autism general symptoms | Mean “autism general symptoms” was 0 | Mean “autism general symptoms” in the intervention groups was 0.31 SD lower (−0.63–0.01 higher) | SMD −0.31 (−0.63–0.01) | 227 | ⊕⊕⊕⊝ | |
| (3 studies) | moderate2 | |||||
| Developmental quotient | Mean “developmental quotient” was 0 | Mean “developmental quotient” in the intervention groups was 0.31 SD higher (−0.02–0.65 higher) | SMD 0.31 (−0.02–0.65)* | 208* | ⊕⊕⊕⊝ | Results of sensitivity analysis excluding studies with a significant baseline imbalance |
| (4 studies) | moderate2 | |||||
| Expressive language | Mean “expressive language” was 0 | Mean “expressive language” in the intervention groups was 0.11 SD higher (−0.07–0.3 higher) | SMD 0.11 (−0.07–0.3) | 457 | ⊕⊕⊕⊝ | |
| (8 studies) | moderate1 | |||||
| Receptive language | Mean “receptive language” was 0 | Mean “receptive language” in the intervention groups was 0.12 SD higher (−0.11–0.34 higher) | SMD 0.12 (−0.11–0.34) | 457 | ⊕⊕⊕⊝ | |
| (8 studies) | moderate1 | |||||
| Reciprocity of social interaction towards others | Mean “reciprocity of social interaction towards others” was 0 | Mean “reciprocity of social interaction towards others” in the intervention group was 0.53 SD higher (0.29 more–0.78 more) | SMD 0.53 (0.29–0.78) | 380 | ⊕⊕⊕⊕ | |
| (8 studies) | High | |||||
| Adaptive behaviour | Mean “adaptive behaviour” was 0 | Mean “adaptive behaviour” in the intervention group was −0.04 SD higher (−0.23 more–0.15 more) | SMD −0.04 (−0.23–0.15) | 414 | ⊕⊕⊕⊝ | |
| (7 studies) | moderate1 | |||||
Interventions for pre-school children with autism spectrum disorder (ASD). Population: Pre-school children aged 6 years or younger with a diagnosis of ASD. Settings: Australia, Canada, Japan, Norway, UK and USA. Intervention: Interventions for pre-school children with ASD
*The basis for the assumed risk (e.g. median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; GRADE: Grades of Recommendation, Assessment, Development and Evaluation; SMD: standard mean difference; SD: standard deviation.
GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.
1 Small sample size with wide CI crossing the line of no effect.
2 Estimate based on small sample size.