Let’s Learn Language was a cluster randomised controlled trial, nested in a population based survey. More than 1200 parents participated in the survey, reporting on their child’s communication and behaviour at ages 12 and 18 months. The 301 children who were ‘slow-to-talk’ at 18 months were invited to participate in the controlled trial, which evaluated the benefits of a low intensity parent-toddler language promotion program.


Study name  Let’s Learn Language 
Study abbreviation LLL
Current principal investigator/s

Prof Melissa Wake

Prof Sheena Reilly

Prof Sharon Goldfeld

Prof Luigi Girolametto

A/Prof Lisa Gold

A/Prof Obioha Ukoumunne

Current project manager Prof Melissa Wake
Cohort representative (study contact) Prof Melissa Wake
Postal address

Centre for Community Child Health

Murdoch Children’s Research Institute

50 Flemington Road

Parkville, VIC 3052

Phone  +61  3 9345 5761
Primary Institution Centre for Community Child Health, Murdoch Children’s Research Institute
Collaborating Institution/s

Royal Children’s Hospital Melbourne

University of Toronto

Deakin University

Major funding sources NHMRC
Study website
Key reference Wake, M., Tobin, S., Girolametto, L., Ukoumunne, O.C., Gold, L., Levickis, P., Sheehan, J., Goldfeld, S., & Reilly, S. Outcomes of population based language promotion for slow to talk toddlers at ages 2 and 3 years: Let’s Learn Language cluster randomised controlled trial. BMJ, 2011;343:d4741. doi: 10.1136/bmj.d4741 
Are data available outside study team? No
Study focus Language development and language delay
Sampling frame

Overall sample: Maternal health centres in 3 local government areas in Melbourne, Australia

RCT: Those children who scored at or below the 20th centile on the expressive vocabulary checklist at age 18 months

Year commenced 2007
Commencement sample

1217 (overall sample)

301 (RCT)

Intergenerational? No 
Imaging No 
Linkage No 
Biosamples? No 
Ethics approvals or requirements? This project only (Specific consent) 


Wave Year Age (mean, range) Eligible sample
1  2007 12 months 1217
2 2007 – 2008  18 months


(301 RCT – 158 intervention, 143 control)

3 2008 2 years RCT intervention 148, control 137
4 2009 3 years RCT intervention 140, control 127