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A Review of the Effect of Classroom Sound-Field Amplification on Children in Primary School.

PURPOSE
Being able to hear the teacher clearly is an important factor for children's learning. However, classrooms often have suboptimal listening conditions. Sound-field amplification systems (SFAS) can help improve classroom listening conditions by increasing the level of the teacher's speech compared to the background noise throughout the classroom. The aim of this review article was to review the effect of SFAS on children in primary school.


METHOD
A comprehensive search of four online databases (ERIC, PubMed, Scopus, and Web of Science) was conducted. The search terms were classroom sound-field amplification and classroom amplified distribution system. Twenty-one articles were deemed relevant for the review plus an additional six from their references.


RESULTS
Most articles were published between 1996 and 2015. Only one article was published since 2016. A range of child populations were studied including typically developing children and children with difficulties and disabilities such as hearing loss, developmental language disorders, attention-deficit/hyperactivity disorder, emotional and behavior disorders, Down syndrome, and developmental disabilities. There were several different measures that were used to evaluate the effectiveness of SFAS including speech perception assessments, language assessments, academic and comprehension assessments, classroom observations, interviews, and questionnaires. Improvements with SFAS were found for speech perception, listening comprehension and auditory analysis, language outcomes, academic outcomes, and behavior.


CONCLUSION
SFAS can benefit children's listening and learning; however, the child's background, classroom reverberation time (limit to < 1 s), and layout and type of learning activities, especially in modern classrooms, need to be taken into consideration.