Objective: To determine, in a community-based sample of slow-to-talk toddlers, the extent to which specific maternal responsive behaviors at 24 months predict child language at 24 and 36 months.
Methods: Mother-child dyads were recruited for this prospective longitudinal study from 3 local government areas spanning low, middle, and high socioeconomic status in Melbourne, Australia. At child age 18 months, 1138 parents completed a 100-word expressive vocabulary checklist; the 251 (22.1%) children scoring ≤20th percentile were then followed up to comprise this study.
Predictors: Six maternal responsive behaviors (imitations, interpretations, labels, expansions, supportive directives and responsive questions) were derived from mother-child free-play videos collected at 24 months of age and coded using the Observer XT system.
Outcomes: Expressive and receptive language measured at 24 and 36 months of age (Preschool Language Scale-4), blind to maternal responsiveness ratings.
Results: Two hundred and twenty-six of the 251 (90.0%) mother-child dyads were followed up at 36 months. In confounder-adjusted linear regression analyses, expansions, imitations, and responsive questions were strongly associated with better receptive and expressive language at 24 and 36 months. Labels unexpectedly predicted poorer expressive language at 36 months. Expansions were the only maternal behavior that predicted improvement in language between 24 and 36 months.
Conclusions: Maternal responsive behaviors, particularly expansions, offer promise in enhancing early language learning in slow-to-talk toddlers. Parent-child interactions characterized by frequent use of maternal labels at 24 months could also be a predictive marker of those slow-to-talk toddlers at greater risk of persistent language problems.
*Community Health Services Research, Murdoch Childrens Research Institute, Parkville, Australia;
†Centre for Community Child Health, Royal Children's Hospital, Parkville, Australia;
‡Department of Paediatrics, University of Melbourne, Parkville, Australia;
§Department of Speech-Language Pathology, University of Toronto, Toronto, Canada;
‖NIHR CLAHRC South West Peninsula (PenCLAHRC), University of Exeter Medical School, Exeter, United Kingdom.
Address for reprints: Penny Levickis, PhD, Centre for Community Child Health, Royal Children's Hospital, Flemington Rd, Parkville VIC 3052, Australia; e-mail: firstname.lastname@example.org.
The Let's Learn Language trial was funded by the Australian National Health and Medical Research Council (NHMRC) Strategic Award 384491. The following authors were supported by the Australian NHMRC and would like to acknowledge the support of the NHMRC-funded Center of Research Excellence in Child Language 1023493. P. Levickis (Postgraduate Scholarship, 491296 and Center of Research Excellence, 1023493), M. Wake (Senior Research Fellowship, 1046518), and S. Reilly (Practitioner Fellowship 1041892). O. C. Ukoumunne is supported by the Peninsula Collaboration for Leadership in Applied Health Research and Care, a collaboration between the University of Exeter, University of Plymouth, and National Health Service South West, funded by the National Institute for Health Research. Research at the Murdoch Childrens Research Institute is supported by the Victorian Government's Operational Infrastructure Support Program. The researchers were independent of the funders.
Disclosure: The authors declare no conflicts of interest.
Received November , 2013
Accepted February , 2014