Table 4.
Summary of outcomes
| Study | Outcomes | ||
|---|---|---|---|
| Parent | Child | Proportion of talking | |
| Girolametto et al. (1996) | Mothers’ language was slower, less complex, and more focused in the treatment group than in the control group. | Children in the treatment group used more target words in naturalistic probes, more words in free-play interaction, and were reported to have larger vocabularies overall as measured by parent report than in the control group. Children in the treatment group used more multi-word combinations and early morphemes than children in the control group. | None reported. |
| Baxendale and Hesketh (2003) | For both groups parent use of modeling techniques improved. | The two types of therapy did not produce significantly different results on the child language outcome measures of MLU and PLS-4. The majority of children (71%) improved. | For both groups parents reduced their amount of talking to balance the interaction. |
| van Balkom et al. (2010) | None reported. | As compared to the control group, the PVHT group showed significant differences on MLU, grammar, conversational coherence, the Reynell Language Development Scales at post-treatment and follow-up. | None reported. |
| Konza et al. (2010) | Parent’s understanding of the program and their children’s communication was reported. All mothers increased their repertoire of strategies. | None reported. | Five of the seven children increased their interactions so that they matched or almost matched the number of communications with their mothers. |
| Wake et al. (2011) | A majority of parents in the treatment group reported positive program benefits and changes in parent–child communication immediately after the final session. | No group differences between groups were identified on vocabulary, language, or behavioral outcomes measures. | None reported. |
| Allen and Marshall (2011) | Parents reduced their amount talk to balance the communication exchange with their child. | Children in the treatment group produced more verbal responses and had greater MLU than children in the control group. No effect on non-verbal responses was noted. Children in the treatment group increased the number of verbal responses, albeit not significantly. | Group differences in the proportion of utterances between parents and children was not noted. |
| Roberts and Kaiser (2012) | Parents in the treatment group had significantly higher rates of strategy use than parents in the control groups. | Group differences were reported in scores on the PLS-4. Group differences in the total number of words between the treatment and control groups were reported. | |
| Pratt et al. (2015) | None reported. | Statistically and practically significant gains on Print and Word Awareness Letter-Name Knowledge, but not for Letter-Sound Knowledge subtests of the PALS (Spanish). | None reported. |
| Falkus et al. (2016) | Significant changes on parent report of strategy use were noted. | Significant changes on MLU were noted. | Significant changes of the ratio parent–child speech were reported. |
| Olson et al. (2016) | Parents reported increased awareness of language-promoting activities, local child development resources, and increased engagement in language-promoting activities | None reported. | None reported. |