A randomized controlled trial of the effectiveness of teacher continued professional development on student language...

Continued professional development (CPD) is required for updated skills and knowledge. This study evaluates the efficacy of a CPD programme for mainstream school teachers.

In an 11-week intervention programme, speech-language therapists (SLTs) presented the participating teachers with whole-class teaching techniques aimed at creating a language and communication-supporting classroom environment. The effects of the intervention on the language development of the students in the teachers' classes were assessed.

A total of 211 first- and second-year students (M_age = 7;6, range = 6;5-8;9) underwent standardized language assessments of receptive and expressive language abilities before and after their teachers' participation in the CPD. The students were divided into intervention and delayed intervention groups to enable randomized intervention allocation. Linear mixed modelling was used to estimate the individual and interaction effects of group, time and demographic factors.

Significant effects of time, group and school, respectively, but no interaction between time and group indicates that while all students advanced between assessments, the progress was not attributable to the teachers' participation in the CPD.

Results are discussed in light of those of recent studies of universal services to support optimal language development.

What is already known on this subject Although inconclusive, previous research indicates that intervention delivered to teachers by SLTs has the potential to improve the language abilities of the students in the teachers' classrooms. What this paper adds to existing knowledge This study explored the language development of first- and second-year mainstream school students whose teachers took part in a CPD programme aimed at establishing language and communication-supporting teaching techniques. Results indicate that the development of the students' language abilities could not be attributed to the teachers' participation in the CPD. What are the potential or actual implications of the work? SLTs are often asked to guide teachers and teaching staff rather than themselves conduct individual assessments and interventions. The results of this trial can be used to inform the discussion on how to prioritize between tasks.