This review evaluated the effects of auditory/language interventions for school-aged children with auditory processing disorder. The authors concluded that there was no compelling evidence to suggest any significant intervention effects on auditory, language or academic outcomes. Potential methodological weaknesses in the review methods suggest that the reliability of the authors' conclusion is uncertain.

To evaluate the effects of auditory/language interventions for school-aged children with auditory processing disorder.

Twenty-eight databases, including CINAHL, PubMed, PsycINFO and The Cochrane Library (which covers databases produced by the Centre for Reviews and Dissemination) were searched for peer-reviewed articles in English published between 1978 to 2008. Key words were reported.

Eligible for inclusion were all studies of active auditory/language interventions (definitions specified in the paper) directly delivered to children aged six to 12 years diagnosed with auditory processing disorder and/or primary spoken language disorder. Excluded were studies of children with autism or autistic spectrum disorder, hearing loss or cognitive disability (IQ below 70), and studies that contained mixed treatments. The outcomes of interest were auditory, language and academic success.

Included were exploratory studies (with few or no controls) and efficacy studies (controlled, quasi-experimental or experimental). The age of included children ranged from five to 14 years. Interventions for children with auditory processing disorder (with or without language disorder) included traditional listening treatments (speech-in-noise training, auditory recognition and auditory discrimination to improve comprehension), auditory integration training, Fast ForWord and Earobics. The included interventions for children with spoken language disorder were dominated by Fast ForWord or Early Fast ForWord prototypes. Session length, frequency and duration varied considerably. Outcome measures were similarly diverse (reported in the paper).

Two reviewers independently selected the studies.

Study quality was assessed by all reviewers across seven domains as follows: study protocol; blinding; sampling/allocation; treatment fidelity; statistical significance; precision; and intention-to-treat. The maximum achievable score was 7 points (efficacy studies) or 6 points (excluding the intention-to-treat criterion for exploratory study designs).

Data were extracted or calculated to enable the presentation of effect sizes (d) and 95% confidence intervals (CI).

The authors did not state how many reviewers extracted the data.

A narrative synthesis was presented. Results were grouped separately on outcomes relating to children with auditory processing disorder, and to those with spoken language disorder.

Twenty-five studies (912 children) were included in the review. The quality of exploratory studies ranged from 1 to 5 out of 6; the quality of efficacy studies ranged from 2 to 7 out of 7. Methodological weaknesses were largely connected with blinding, treatment fidelity and sampling/allocation.

Outcomes for children with auditory processing disorder, with or without spoken language disorder (six studies: four exploratory, two efficacy; 121 children):

In children who received traditional listening treatments, one poorer quality efficacy study and three exploratory studies reported positive auditory outcomes; another exploratory study found mixed results for written language outcomes. No differences were found between auditory integration training and controls on a range of behavioural and physiological variables (one efficacy study). There were improvements in auditory outcomes, and mixed results for spoken language measures, following the Fast ForWord intervention (two exploratory studies).

Outcomes for children with spoken language disorder (nineteen studies: 12 exploratory, seven efficacy; 566 children):

For auditory outcomes following Fast ForWord interventions, one efficacy study showed a significant improvement in syllable sequencing and four exploratory studies found some positive effects in favour of the intervention. Mixed results were reported from five efficacy studies of Fast ForWord in terms of language or phonology outcomes. This intervention produced one or more positive language or phonology outcome in six exploratory studies, but the overall results were mixed (some negative outcomes were reported). Two efficacy studies showed large gains in phonological awareness, but the gains could not be attributed directly to the Fast ForWord intervention. There were no significant group differences in written language outcomes following Fast ForWord, Earobics, and Lindamood-Bell Learning Processes interventions (one efficacy study; two exploratory studies). There was no convincing evidence favouring an intervention similar to Fast ForWord (language oriented with acoustic modifications) in two efficacy studies measuring auditory processing and phonological tasks. In a case study, the child who received auditory discrimination training showed no gains in language outcomes.

There was no compelling evidence that existing auditory interventions made any significant contributions to auditory, language or academic outcomes of school-aged children who were diagnosed with auditory processing disorder or spoken language disorder .

The review question and inclusion criteria were clearly stated. Children aged outside the specified selection criteria were included, without explanation. This discrepancy with the inclusion criteria potentially affected the reliability and generalisability of the review findings. Several relevant data sources were searched. The applied language and publication restrictions meant that suitable studies might have been overlooked, and the associated biases could not be ruled out. The processes of study selection and quality assessment were carried out with attempts to minimise reviewer error and bias; it was not possible to determine this for data extraction. Quality criteria were largely appropriate only for efficacy studies. However, quality results were reported clearly and demonstrated variability in the robustness of included studies. The method of synthesis was appropriate given the observed clinical variation.

Some methodological weaknesses identified above means that the reliability of the authors' conclusion is uncertain.

Practice: The authors stated that clinicians should be aware of the limited evidence for auditory interventions, and ensure that the spoken and written language status of their patients is monitored before and after any intervention. Auditory interventions should be chosen in conjunction with others that target specific language, communication and academic goals.

Research: The authors stated that future rigorous smaller scale studies should focus on thematically coherent programmes where participants are evaluated using a comprehensive battery of conventional tests for auditory processing disorder, along with sophisticated neurophysiological indices and psychoacoustic measures. Interventions that show promise should ultimately be tested in larger experimental trials.

Not stated.