The relationship between parents' responsiveness to their infant's early communication and its subsequent growth, within the current societal context: A comprehensive systematic review.

Abstract

Background The importance and protective nature of children's early communication capacities, from birth to preschool years, in relation to later academic and social functioning is well established in the literature. Studies have shown links between early language competence (from birth to preschool) and later language, literacy, behavioural and social outcomes 1-3 as well as language, literacy and numeracy being shown to serve as key protective factors for positive life outcomes.4 The term ‘communication’ includes speech (the physical production of sounds), language (understanding and expression of spoken and written language, from sounds to words to sentences, to discourse), pragmatics (the social use of language in interactions), fluency (the smooth rhythm and pattern of talking) and voice (the production of sound through the vocal cords). 5, 6 Prelinguistic and early language development are the areas of communication that are of primary interest in this systematic review because they are the predominant aspects of communication that studies measure, when investigating the impact of parent responsiveness on children's communication development. Prelinguistic communication skills are the foundation skills that facilitate infants' communication competence.7-10 The prelinguistic period is typically from 0-12 months and skills include early vocal behaviours such as cooing and babbling,5 symbolic and functional play,(cited in 7) attention,11, 12 gestures such as facial expression,13 eye contact, turn taking, copying9 and phonetic (speech) perception.10 Language development encompasses the sub-components of sound and sound patterns (phonological development), words (lexical development), sentences and grammar (syntactic and morphological development) and the development of communicative competence, incorporating pragmatic skills (language use in a social context).5 Communication development starts from the prelinguistic period and is influenced by environmental factors including parental (particularly maternal) responsiveness and directiveness. Responsiveness refers to adults' ‘prompt, contingent, and appropriate’ (cited in 14 pp64) responses to a child's behaviours. This definition underpins the various aspects or descriptions of responsiveness that have been researched in relation to children's communicative development, for example: maternal encouragement,15 supportive parenting, 16 interpersonal timing, 17 and maternal behavioural and verbal responsiveness.14 Masur and colleagues14 also discuss the importance of considering directiveness (as well as responsiveness) when investigating the impact of parent speech and behaviour on children's communication development. Directiveness is described as being ‘characterised by attempts to command and control children's behaviour or attention’ 14(pp64) and may be supportive or intrusive in nature. Research has shown predictive relationships between parental responsiveness and directiveness and children's language development.14,16,18,19 Enhancing parent responsiveness to children's early communication can have positive effects on child development, social development, self esteem, the attachment relationship between parent and child literacy outcomes. 20-23 Hence, parents, as the primary caregivers, are in a powerful position to influence their child's communication development, and subsequent academic and social success, through the way they respond to their children from birth. The importance of this systematic review This systematic review aims to support and direct evidenced based practice and health promotion in speech pathology and related fields that work with parents and infants or children. To the reviewer's awareness, no systematic reviews on the relationship between parent responsiveness and children's communication development have been developed to date. Systematic reviews can play a role in the education of health professionals and lay people.24 A systematic review on the relationship between parental responsiveness and children's communication development could support health professionals and policy makers in easily accessing synthesised information on this topic. Prevalence data on speech-language difficulties in 2 to 4 ½ year olds has been reported as 5-8%. (cited in 25 & 26) Whilst this percentage is not categorized into causal factors, it is plausible, based on the research on parental responsiveness, that a proportion of these children have speech-language difficulties due to a reduced level of parental responsiveness in their early learning environment. Despite the established evidence regarding the importance of maternal responsiveness on children's early communication development, which in turn, influences later life outcomes, it is the reviewer's opinion that this information is not widely promoted in the general community to serve as a preventative measure. Using Gordon's operational classification of disease prevention, a universal or selective preventative measure would include public education as ‘an essential aspect of the strategy for optimal public health practice’. 27 (pp108) According to Gordon a universal preventative measure is desirable for everybody in the general population (i.e. all parents of infants or expectant parents), while a selective preventative measure is aimed at subgroups of the population who are considered to have characteristics that place them ‘at risk’ (i.e. parents who are at risk of being less responsive to their infants). This systematic review could encourage the focus of universal or selective health promotion and policy development on educating society about the benefits and importance of parent responsiveness in relation to child development outcomes. Health promotion and early parent education on the parent's role in children's early communication development could potentially reduce the number of preschool and school-age children with speech-language difficulties, hence reducing the economic, social and individual costs of this issue. This comprehensive systematic review will incorporate both quantitative and textual components. A preliminary search of the literature has found that studies on parental responsiveness and children's communication development are quantitative by nature. The textual component of this review will set the context of current thinking and action in society in relation to the quantitative component. The textual component is important because it will investigate whether the research is being put into action, or at least has a profile in society. The textual component may help to clarify the direction, if any that government needs to take regarding public education on this topic. A qualitative component of this systematic review is not included because a preliminary search did not identify any qualitative papers, and a qualitative approach is not required to answer the research question presented. Review question/objective The quantitative objective of this review is to determine the best available evidence on the relationship between parents' responsiveness to children's prelinguistic and early communication and their subsequent communication development. More specifically, the questions are: What are the attributes of parental responsiveness? That is: To delimit the attributes of parents' verbal and behavioural responsiveness and directiveness that influences children's preverbal and early communicative development. Do some attributes of parent responsiveness have more consequence to children's early communication development than others? Is the amount or frequency of parent responsiveness important? That is: Do varying levels of parent responsiveness impact differently on children's communication development? Are there parental factors (e.g. education level) within the well population that predict or influence responsiveness quality and quantity? If so, what are they? The textual objective is to identify the current social context within Australia, regarding the topic of parental responsiveness and children's communication development. More specifically, the questions are: Does current government policy on child development reflect the research evidence identified in the quantitative component of this systematic review? What is society's current awareness and standing (perception) on this topic, as identified through policy, expert and public opinion? Are there preventative universal or selective health promotion measures in place relating to the review question? If the answer to question 3 is ‘yes’, then what are they? Inclusion criteria Types of participants The quantitative component of this review will consider studies that include parents as the primary independent variable and children as the secondary, dependent variable. More specifically, the review will include studies with: 1. Parents Because a main goal of this review is to support public education for universal or selective health promotion, parents who are identified as falling within the well or at risk, but not clinically significant population will be included. Well parents refer to the general public who are not affected by current suffering. 27At risk parents may include parents whose social circumstances place them at risk of being less responsive to their children. For example, parents of low education or intellectual capacity, or of certain age. At risk parents will be included in this review because they have characteristics that place them in a position for selective preventive health promotion 27 and could provide insight into the outcomes of varying levels of parent responsiveness to children. The term clinically significant refers to parents who have clinical diagnoses that impact on their capacity to respond to their children. For example, hearing impairment, and mental illnesses such as psychoses, schizophrenia, clinical or post-natal depression. These parents are excluded from the review because they present compounding factors that are beyond the scope of this review. 2. Children Children who's language level is preverbal (i.e. prelinguistic period) up to production of early phrases (E.g.: two-word utterances) will be included in this systematic review. Based on child development norms, these ages would typically include 0 - 3 year olds, however, studies that have older cohorts will also be included, providing the earlier years are also represented within the study. Children who are typically developing, or defined as a ‘late talker’ or as having a specific speech/language issue will be included in this systematic review because these studies may reveal important information about parent responsiveness as a causal or influencing factor. Studies may or may not have control groups. Studies will not be considered for this review when children are identified as having any primary co-morbid condition such as syndromes, global developmental delays or disorders, Autism Spectrum Disorder, or hearing issue including hearing impairment and cochlear implant because this introduces too many confounding factors. Studies on bilingual children will not be included for the same reason. Consideration will be made as whether to include children who spend care time with a carer other than their primary parent/caregiver, for example, childcare. The amount of time spent in the care of persons/institutions other than their parents is important to consider because the review is examining the relationship between the parent's impact on the child through their responsiveness attributes and levels. It is beyond the scope of the review to consider the language development of children independent of their parent's responsiveness. The reviewer will examine the literature to determine the cut off point for time spent in childcare. Where this is not clear, the reviewer will contact the authors of the studies for this specific information. The textual component of this review will consider discourse and opinion reported or published by government agencies, experts, the public and media, about the systematic review question, that is of direct relevance or interest to Australia. Types of intervention(s) The quantitative component of the review will consider any studies that evaluate parent verbal and behavioural responsiveness and directiveness to their children's preverbal and or early linguistic communication. Studies may investigate parent responsiveness and or directiveness in the context of a home or clinical/education environment. The reviewer will take the environment (e.g. home, laboratory, community settings) in which studies gather their data into consideration throughout the review process. The textual component of this review will consider published and unpublished papers that describe society's and government's current attitudes and opinions regarding the topic of parental responsiveness to infant and early communication. Types of outcomes The quantitative component of this review will consider studies that include outcome measures of child prelinguistic and early language development. This includes, but is not limited to, measures of language milestones such as comprehension of first words, speech sound perception, babbling, first word production, first 50 words and first 2-word utterance. The process of the systematic review may reveal other important prelinguistic or early language outcomes, which may be considered for inclusion depending on the validity, reliability and standardisation of the tools used to obtain the data. The preferred type of assessment tools used to retrieve data about child language outcomes will be standardised language/communication assessments. However, parent reports and non-standardised assessments will also be considered for inclusion. The textual component of this review will consider discourse and opinion about the topic of parental responsiveness and children's communication development, as reported in textual or policy papers. The outcome will be the main themes and concepts identified through expert and society opinions, and government policy, in relation to the review question. Types of studies The quantitative component of the review will consider analytical epidemiological study designs including prospective and retrospective cohort studies, case control studies and analytical cross sectional studies for inclusion. Randomised control trials of parent responsiveness are not ethically possible, therefore will not be included in this review. Case series studies have not been identified in preliminary search of the topic, therefore will not be included in this review. The textual component will consider expert opinion, discussion papers, position papers, government policies and reports, conference papers, theses and dissertations, and other text relating to child development/health promotion/early education within the context and parameters of the review question. Discourse must be written in English and be of western culture. Discourse from Australia is of primary interest. Discourse from other countries that constitute western society (i.e.: the Americas, New Zealand and Western Europe)28 will only be included where it has been shown to be of interest to Australia. For example, an Australian expert has commented on a paper from another Western country. Search strategy The search strategy aims to find both published and unpublished studies. A three-step search strategy will be utilised for each component of this review. An initial limited search of PubMed and CINAHL will be undertaken followed by analysis of the text words contained in the title and abstract, and of the index terms used to describe article. A second search using all identified keywords and index terms will then be undertaken across all included databases. Where necessary, terms and indexing language will be adjusted to search the other databases listed. This process will be done in close consultation with the Research Librarian for Mental Health, Psychiatry, Psychology, University of Adelaide. Thirdly, the reference list of all identified reports and articles will be searched for additional studies. Studies published in English will be considered for inclusion in this review. As there are no other identified systematic reviews on this topic, any quantitative studies within an unlimited timeframe will be considered for inclusion in this review, in order to increase the breadth of the results and so not to miss any pertinent earlier studies. To keep textual information of current opinion and policy relevant and up to date, the timeframe will be the past 10 years (2002 - 2012). The databases to be searched include: PubMed PsycINFO CINAHL Embase Scopus Web of Science Mednar Proquest Dissertations and Theses Index to Theses Australian Digital Theses Program The Networked Digital Library of Theses and Dissertations (NDLDT) Keywords and concepts to be used for the initial search of PubMed and CINAHL will include:Table: No Caption available.The search for textual information will also include relevant websites in the English language, related to child development, literacy, parent-infant attachment, government policy on early childhood development and education, and media releases relating to the review question. An initial search to identify a comprehensive list of relevant websites for grey literature will be done through the Google search engine using initial key words seen above and additional keywords including: Government policy Early childhood Parent education Parent training Infant mental health Expert opinion(s) Individual countries (eg Australia, New Zealand, Canada, America, United Kingdom) Examples of potential grey literature sites include: Australian Government Department of Health and Ageing Australian Government Department of Education, Employment and Workplace Relations Council of Australian Governments The Hanen Centre. Speech and Language Development for Children Assessment of methodological quality Quantitative papers selected for retrieval will be assessed by two independent reviewers for methodological validity prior to inclusion in the review using standardised critical appraisal instruments from the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI) (Appendix I). Textual papers selected for retrieval will be assessed by two independent reviewers for authenticity prior to inclusion in the review using standardised critical appraisal instruments from the Joanna Briggs Institute Narrative, Opinion and Text Assessment and Review Instrument (JBI-NOTARI) (Appendix I). Any disagreements that arise between the reviewers will be resolved through discussion, or with a third reviewer. Data collection Quantitative data will be extracted from papers included in the review using the standardised data extraction tool from JBI-MAStARI (Appendix II). Textual data will be extracted from papers included in the review using the standardised data extraction tool from JBI-NOTARI (Appendix II). The data extracted will include specific details about the interventions, populations, study methods and outcomes of significance to the review question and specific objectives. Data synthesis Quantitative papers will, where possible, be pooled in statistical meta-analysis using JBI-MAStARI. All results will be subject to double data entry. Effect sizes expressed as relative risk for cohort studies and odds ratio for case control studies (for categorical data) and weighted mean differences (for continuous data) and their 95% confidence intervals will be calculated for analysis. A Random effects model will be used and heterogeneity will be assessed statistically using the standard Chi-square. Where statistical pooling is not possible the findings will be presented in narrative form including tables and figures to aid in data presentation where appropriate. Textual papers will, where possible be pooled using JBI-NOTARI. This will involve the aggregation or synthesis of conclusions to generate a set of statements that represent that aggregation, through assembling and categorising these conclusions on the basis of similarity in meaning. These categories are then subjected to a meta-synthesis in order to produce a single comprehensive set of synthesised findings that can be used as a basis for evidence-based practice. Where textual pooling is not possible the conclusions will be presented in narrative form. Conflicts of interest The primary reviewer is not aware of any conflicts of interest at the time of submitting the systematic review protocol. Acknowledgements The primary reviewer would like to acknowledge the support of the secondary reviewer, Matthew Kowald; her principal supervisor, Dr Aye Aye Gyi from the Joanna Briggs Institute, University of Adelaide; her associate supervisor, Dr Debbie James from Research and Evaluation Unit, Children, Youth and Women's Health Service, and Maureen Bell, Research Librarian for Mental Health, Psychiatry, Psychology, University of Adelaide. As this systematic review forms partial submission for the award of Masters of Clinical Sciences degree, a secondary reviewer will be used for critical appraisal only.