Health-related quality of life, service utilization and costs of low language: A systematic review

Low language (LL) is a common childhood condition affecting 7-17% of children. It is associated with life-long adverse outcomes and can affect various aspects of a child's life. However, the literature on its impact on health-related quality of life (HRQoL), service use and costs are limited. To date, there has been no systematic review of the overall economic burden of LL. A systematic review regarding the economic burden of LL is important for clinical, educational, policy decision-making and theoretical aspects. We adopted the term 'low language' to refer to children whose language performance falls below well-recognized cut-points regardless of known or unknown aetiology.

To review the literature systematically on how LL is associated with HRQoL, service utilization and costs.

A systematic search was conducted across various databases, including MEDLINE, Embase, PsycINFO, CINAHL, up to July 2017. Data on study design, population and outcomes were extracted and screened by two pairs of reviewers with the revision of other experts in the panel on any discrepancies. The Effective Public Health Practice Project tool was used to assess the risk of bias of the included studies. The findings of the included studies were summarized in a narrative synthesis.

We identified 22 relevant articles, of which 12 reported HRQoL and 11 reported service utilization and costs associated with LL. Preference-based instruments, which include the relative importance attached to different aspects of HRQoL, were less employed in the literature. Most studies found poorer HRQoL in children with LL compared with their peers. About half the families having children with LL did not actively seek professional help, and many families felt they did not receive sufficient services when needed. Healthcare costs associated with LL were substantial. Non-healthcare costs were largely unexplored.

LL was associated with reduced children's HRQoL, higher service use and costs. Under-servicing was evident in children with LL. LL also imposed large costs on the healthcare system. Further research is required to examine (1) the overall HRQoL of children with LL, in particular studies using and testing the performance of preference-based instruments; and (2) the service use and costs specific to LL, especially non-healthcare costs.