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Improving children’s language, literacy and mental health: Evaluating the impact of the classroom promotion of oral language (CPOL) approach.
Last registered on September 14, 2015


Trial Information
General Information
Improving children’s language, literacy and mental health: Evaluating the impact of the classroom promotion of oral language (CPOL) approach.
Initial registration date
September 14, 2015
Last updated
September 14, 2015 11:58 PM EDT
Primary Investigator
The University of Melbourne
Other Primary Investigator(s)
Additional Trial Information
On going
Start date
End date
Secondary IDs
Language competence (including spoken communication and literacy) is a major influence on children’s developmental pathways and life success. The ability to communicate and use language effectively impacts upon the capacity of children to learn, on their mental health and behaviour, on their future educational and employment achievements, and on their social and community participation opportunities. As a teacher’s effectiveness has a powerful impact on students, this study will determine whether a teacher professional development program can lead to improved teacher knowledge and practice leading to improved student outcomes in oral language, literacy and mental health for early years’ primary school children.
External Link(s)
Registration Citation
Goldfeld, Sharon. 2015. "Improving children’s language, literacy and mental health: Evaluating the impact of the classroom promotion of oral language (CPOL) approach.." AEA RCT Registry. September 14. https://doi.org/10.1257/rct.622-5.0.
Former Citation
Goldfeld, Sharon. 2015. "Improving children’s language, literacy and mental health: Evaluating the impact of the classroom promotion of oral language (CPOL) approach.." AEA RCT Registry. September 14. https://www.socialscienceregistry.org/trials/622/history/5259.
Experimental Details
In 2014, teachers in the intervention arm of the study will attend three face-to-face days of professional learning convened by the research team, and will also engage in a self-directed manner in an online learning network of teachers in like-schools in the first half of 2014. A fourth day of face-to-face learning will be held in February 2015. The professional learning delivered to teachers is based on Munro’s (2011) ICPALER (Ideas, Conventions, Purposes, Ability to Learn, and Reception) Framework, and was the subject of a successful large-scale pilot led by CI Snow (Snow et al., in press). In addition to these formal days of professional learning and access to the online forum, teachers will liaise with CPOL Support Officers, via intermittent face-to-face, telephone, and online contact, in order that questions are addressed and program fidelity is enhanced.
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
Primary outcome:
When the study cohort is in Grade 3 (2017), we wish to evaluate student literacy skills, and pla to access and use their National Assessment Program Literacy and Numeracy (NAPLAN) data as one outcome measure against which to evaluate the impact of the CPOL investigation. NAPLAN is made up of tests in the following four domains:
• Reading
• Writing
• Language Conventions (spelling, grammar and punctuation)
• Numeracy.
A full description of the way in which NAPLAN is administered is available at: http://www.nap.edu.au/naplan/naplan.html NAPLAN is administered by the Australian Curriculum Assessment and Reporting Authority (ACARA) - http://www.acara.edu.au/default.asp

Primary outcomes:
Child Literacy at Grade 3 (2017) , assessed through students’ grade 3 NAPLAN score: ‘Reading’ category

Secondary outcomes:
• Child oral language at Grade 3 (2017), assessed through:
• Students’ NAPLAN scores: Categories including: ‘Writing’, ‘Language Conventions’, and ‘Numeracy’
• Reading Progress Test: End Grade 1 (2015)
• Additional language measures: CELF-4 subscale, Bus Story Test, NPVT (digitised version of the Peabody Picture Vocab Test) End Grade 1 (2015)
• Child mental health end Grade 1 (2015), assessed through: Strengths and Difficulties Questionnaire
• Teacher practice assessed at the end of Prep (2014) and end Grade 1 (2015) (Teacher oral recording/Self reflection/Teacher Survey/Teacher focus groups)

Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
Cluster Randomised Controlled Trial
Experimental Design Details
Randomization Method
Computer randomisation.
Randomization Unit
Participants are clustered at the school level:

Schools will be selected for inclusion in this study based upon the 2009 and 2012 Australian Early Development Index (AEDI) data for their school. Schools with AEDI results in the language and cognitive skills domain with vulnerability rates of ≥ 10% who had at least 10 children participate in the AEDI will be eligible to participate in this trial. DEECD and CECV will arrange their own calls for Expressions of Interest from the pool of eligible schools across the state of Victoria. From this pool, schools that were identified as vulnerable in both the 2009 and 2012 AEDI data will be approached first, after which schools vulnerable only on the 2012 AEDI will be approached.

All children in one classroom at each school will be allocated together as a single unit for randomisation (‘the cluster’). This is the most appropriate approach to randomisation given the intervention will be focused on teacher professional learning and the implementation of that knowledge within a whole-of-classroom approach. It will also limit the potential for contamination by separating the trial arms at the school level. Following baseline data collection, schools will be stratified by sector and allocated randomly - using a random number table - to one arm by an independent, blinded statistician otherwise unconnected with the study.
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
72 schools
Sample size: planned number of observations
1450 participants including students and teachers.
Sample size (or number of clusters) by treatment arms
36 schools control, 36 schools treatment
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
The sample size calculation is bound by the assumption that 80 points is the average gain in the NAPLAN Reading score over 2 years, therefore around 40 is the average gain in the Reading score over 1 year. For this study we aim to find a difference between the intervention and control groups in the Reading score of 0.3 SDs (22.47 points). An effect sizes of 0.3 SDs can be meaningful at a population level given the reach. In this trial in particular it is an approximate 6 month difference in progress and would represent a “clinically” significant difference in outcomes. Randomisation of 561 children per arm is required to provide 90% power to detect a minimum difference of 0.3 standard deviations on the NAPLAN ‘Reading’ scores at grade 3, allowing for an average intra-class correlation coefficient of 0.08 and an average cluster size of 17. To allow for a potential attrition rate of 20% of children by the time children are in grade 3, 700 children per arm (1400 in total) will be required in the study. This sample size also allows for a retention rate of 8% of clusters.
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Is data collection complete?
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports and Papers
Preliminary Reports
Relevant Papers