TABLE 3.
Outcome Comparisons
| Outcome | Mean (SD) for Trial Arms | Adjusted | ||||
|---|---|---|---|---|---|---|
| Intervention (n = 45) | Control (n = 43) | Mean Difference (Intervention − Control) | 95% Confidence Interval | P | Effect Size | |
| Primary child outcomes | ||||||
| Expressive language, PLS-412 | 84.0 (13.9) | 80.2 (12.0) | 0.37 | −4.5 to 5.3 | .88 | 0.03 |
| Receptive language, PLS-412 | 86.3 (19.4) | 77.3 (20.4) | 5.3 | 0.15 to 10.4 | .04 | 0.27 |
| Secondary child outcomes: Expressive Vocabulary | ||||||
| MCDI14 | 263.7 (172.6) | 214.5 (146.3) | 32.8 | −17.3 to 83.0 | .20 | 0.21 |
| NDW | 54.9 (30.2) | 38.0 (30.3) | 11.4 | 2.5 to 20.4 | .01 | 0.38 |
| EOWPVT-313 | 75.7 (16.3) | 70.0 (17.7) | 3.5 | −4.2 to 11.12 | .40 | 0.21 |
| Secondary child outcomes: Receptive Vocabulary | ||||||
| PPVT-416 | 94.3 (13.6) | 85.6 (16.7) | 5.3 | 0.4 to 10.5 | .04 | 0.35 |
| Primary caregiver outcomes, % | ||||||
| Matched turns | 74 (13) | 32 (15) | 40 | 34 to 46 | <.01 | 2.86 |
| Responsiveness | 85 (9) | 80 (14) | 5 | 1 to 10 | .05 | 0.43 |
| Targets | 47 (21) | 3 (4) | 39 | 33 to 45 | <.01 | 2.55 |
| Expansions | 42 (18) | 4 (4) | 42 | 35 to 48 | <.01 | 3.19 |
| Time delays | 42 (38) | 0 (0) | 29 | 18 to 40 | <.01 | 1.07 |
| Prompting | 50 (38) | 3 (9) | 35 | 17 to 53 | <.01 | 1.25 |
| Secondary caregiver outcomes | ||||||
| Stress, PSI15 | 194.2 (43.4) | 216.6 (38.2) | −6.7 | −16 to 2.6 | .15 | −0.16 |
Effect size calculated by dividing the adjusted mean difference by the pooled SD of the intervention and control arms. Adjusted analyses include baseline scores, household income, and child cognitive scores as covariates. PLS-4, Preschool Language Scale, Fourth Edition; MCDI, MacArthur Bates Communication Development Inventories; NDW, number of different words in a 20-minute play interaction; EOWPVT-3, Expressive One-Word Picture Vocabulary Test, Third Edition; PPVT, Peabody Picture Vocabulary Test, Fourth Edition; PSI, Parenting Stress Index, Fourth Edition.