|Interaction training for conversational partners of children with cerebral palsy: a systematic review
|Pennington L, Goldbart J, Marshall J
This review assessed the effects of training for conversational partners of children with cerebral palsy upon changes in interaction style and communication development. Whilst the review was well conducted, the quality of the small number of included studies was poor. The authors' conclusion pertaining to further rigorous research involving different interventions and subgroups was substantiated.
To investigate the relative effectiveness of models of communication training for conversational partners of children with cerebral palsy (CP).
Several electronic databases were searched up to December 2002: MEDLINE (from 1966), CINAHL (from 1982), EMBASE (from 1980), PsycINFO (from 1967), ISI Web of Science (from 1990), Linguistics and Language Behaviour Abstracts (from 1973), British Education Index (from 1986), the National Research Register, ERIC (from 1966), ASLIB Index to Theses (from 1970) and SIGLE (from 1980); the search terms were reported. In addition, the authors handsearched journals and conference proceedings, checked reference lists, contacted authors of included studies in relation to unpublished trials, and consulted national professional associations for advice.
Study designs of evaluations included in the review
Studies that included an element of experimental control were eligible for inclusion in the review. Observational studies were excluded.
Specific interventions included in the review
Studies of any training intervention aimed at changing the style of the conversational partners' interaction to improve children's communication development were eligible for inclusion. Aspects of training included speech production, positioning, language development, and the use of augmentative and alternative communication (AAC) systems. The included studies described interventions that were conducted largely on a one-to-one basis, targeting increased responsiveness, reduced directiveness, positioning and the use of AAC systems.
Participants included in the review
Studies of conversational partners of children aged 0 to 19 years with a communication disorder (regardless of severity of impairment) linked to a medical diagnosis of CP were eligible for inclusion. The participants in the included studies were mothers, fathers, or teachers and educational assistants. The target children were aged from 8 months to 17 years, and had various types and severity of CP and associated cognitive development. Other developmental characteristics were reported to be poorly described.
Outcomes assessed in the review
The authors did not report any inclusion criteria relating to the outcomes. The primary outcome of interest was a change in partners' interaction style. Secondary outcomes, namely increases in the infants' voluntary responsiveness and vocalisation, were also measured. No details of the measurement tools were given.
How were decisions on the relevance of primary studies made?
One reviewer assessed the identified studies for inclusion. Three reviewers discussed and resolved any uncertainties about inclusion.
Assessment of study quality
The quality of group studies was assessed in terms of the following: participant allocation to group, allocation concealment, inclusion criteria, similarity of the groups, sample size, blinding of the assessors, protocol compliance, missing values and loss to follow-up. Coding criteria were taken primarily from the Centre for Reviews and Dissemination Report 4. The assessment of single-case studies was based on the description of the participant and intervention, blinding of the assessor, suitability of the control behaviour, assignment of behaviour to intervention or control, baseline adequacy, duration of treatment and follow-up, and frequency of measurement across the phases of the experiment. Two reviewers independently reviewed the studies using the validity criteria described. Any disagreements were resolved with a third reviewer.
Two reviewers independently extracted the data from the studies, using a tool designed for the review. Any disagreements were resolved with a third reviewer. Data relating to the content and duration of training, and outcomes were collected.
Methods of synthesis
How were the studies combined?
The studies were combined in narrative form.
How were differences between studies investigated?
Differences between the studies were discussed narratively in relation to participants, intervention content and observed outcomes in each of the studies. There was no apparent weighting of the studies.
Results of the review
Four studies were included in the review. Three of these were group studies: one was a randomised controlled trial involving 20 mothers and 20 children; two were controlled before-and-after studies, one involving 33 teachers and/or assistants and 9 children, and the other involving 4 children, 4 parents and an unstated number of teachers. In addition, there was one single-case experiment comprising one mother and one child.
In all four studies there were positive changes in interaction style as a result of the interventions, compared with no change in untrained participants. In particular, one study found that shorter duration training (one home visit of one hour in duration) was associated with positive changes in the physical components of conversation (e.g. aspects of increasing responsiveness and positioning, reducing directiveness and therapeutic holding). This study appeared to be of reasonable methodological quality relative to the other studies.
Training of longer duration was associated with improved verbal strategies, including the use of communication boards, reducing speech rates, positioning, prompting AAC use and the use of open questions. Positive secondary outcomes (improvements in infants' voluntary responsiveness and vocalisation) were reported in three studies.
The results of the validity assessment revealed that all studies presented at least one of the following methodological problems: absence of random allocation; poor description of the participants and lack of eligibility criteria; small sample size; absence of assessor blinding; poor description of the interventions; multiple testing of the data; uncertainty regarding the validity of measurement tools; and lack of follow-up. There was heterogeneity in the characteristics of the participants and interventions, with, according to the authors, some aspects very poorly described.
Whilst the current review suggested positive trends in communication changes resulting from interaction training, good-quality research is still required to ascertain the relative effectiveness of different interventions and in different subgroups.
The question and inclusion criteria (in relation to interventions, participants and study design) were clearly stated for this review. These were followed by a comprehensive search and a sound validity assessment. Failure to involve more than one reviewer at the initial study selection stage was a potential source of bias, although other stages of the review process appeared to be conducted rigorously. Details of all primary studies were supplied. However, the authors acknowledged (amongst other methodological problems) that more in-depth descriptions of the participants and interventions would have substantially aided the investigation of effectiveness and generalisability of the results. The validity of the small number of included studies was generally poor, thus the authors' conclusions are substantiated. A thorough proposal for future research was given.
Implications of the review for practice and research
Practice: The authors did not state any implications for practice.
Research: The authors stated a number of areas for future research. These included proposals to build upon the specific interventions (and with different subgroups of partners and children) contained within the current review in relation to the feasibility of future research designs. Others concerned the need to strengthen the methodological rigour of studies. The authors also pointed out the potential value in evaluating the acceptability of interventions to children and their families, an area potentially best served through qualitative methodologies.
Funded in part by a BT Bursary.
Pennington L, Goldbart J, Marshall J. Interaction training for conversational partners of children with cerebral palsy: a systematic review. International Journal of Language and Communication Disorders 2004; 39(2): 151-170
Subject indexing assigned by NLM
Adolescent; Cerebral Palsy /psychology /rehabilitation; Child; Child, Preschool; Communication Disorders /etiology /rehabilitation; Humans; Infant; Interpersonal Relations; Parent-Child Relations; Parents /education; Speech Therapy /education
Database entry date
This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.