Internationally, hospital and primary health care systems have come under increasing strain as a result of ageing populations and a rise in chronic disease . Australia sits around the middle of OECD countries in terms of the number of hospital episodes per 1,000 population . Initiatives to reduce primary health and hospital inefficiencies have led to the identification of large health inequalities, in particular for Aboriginal and Torres Strait Islanders, people with mental illness and those living in remote areas of Australia . Missing from these health care initiatives are people with intellectual disability - another group who similarly experience large health and health care inequities . Intellectual disability has its onset before the age of 18 years, is characterised by lifelong limitations in IQ (70 or less) and adaptive functioning and accounts for 1% to 3% of the world’s population . In developed countries, people with intellectual disability (a) have higher mortality rates and shorter life expectancy than the general population, (b) have greater health care needs, (c) engage in fewer preventative health screenings, and (d) have conditions that often go undiagnosed or are mismanaged -. They are also high users of hospital services. Recent international data demonstrate that people with intellectual disability use hospital services, particularly emergency departments (ED), more often than other people, especially for conditions more appropriately treated elsewhere (such as out-patient or primary care clinics), and their stays are longer -.
In Australia, there have been few attempts to compare the experiences and outcomes of hospitalisations among people with intellectual disability to those of the general population. There has, however, been some acknowledgement of their experience of health inequalities in the National Disability Strategy that is driving large scale reform of the interface between mainstream and specialist disability services and support, and has resulted in a National Disability Insurance Scheme to provide a sustainable individualised funding model to deliver disability services . This strategy was the impetus for a recent state government commissioned report, which provides the most detailed analysis of hospital usage for people with intellectual disability in Australia . Linking disability services and health department data, hospital separationsa were determined for disability clients, predominantly intellectual disability, physical disability, and acquired brain injury, each year from 2005-2010. This analysis revealed their over-representation in the hospital data, with some service users having as many as 8.7 times that of the general population. The last year of data indicated they accounted for 11% to 17% of high end hospital separations and ED presentations, yet accounted for around 68% of all bed days, 44% to 67% of separations, and around 65% of hospital costs .
It would seem, then, that people with intellectual disability are high frequency and costly users of hospital services. Unfortunately, there is mounting evidence that they are at particular safety risk in acute hospital settings  and have poor experiences, in some cases pointing to institutional discrimination ,,. Research into the hospital experiences of people with intellectual disability has been driven in the UK by a peak body report describing the disturbingly poor hospital treatment of six adults who died in hospitals in England and Wales, arguably as a result of neglect, discrimination, and mismanagement . Despite government effort  to adopt 10 recommendations from an independent inquiry , there has been recent evidence of continued neglect and discrimination, with dire outcomes for hospital patients with intellectual disability . Most recently, a UK population-based confidential inquiry revealed that avoidable deaths (preventable or amenable through good quality care) were more common among people with intellectual disability than the general population: 37% vs. 13% of avoidable deaths . The contributors were failures in health care provision that resulted in delays in diagnosis and treatment.
The UK case studies  and population study reflect experiences in other countries. Iacono and Davis , for example, provided reports by family and paid carers of people with intellectual and/or physical disabilities in Australia, which pointed to negative attitudes by hospital staff, delays in diagnostic evaluations and treatment, and reliance on family and paid carers for both advocacy and care during hospital encounters. Others have similarly explored the experience of hospital encounters for people with intellectual disability, including in Australia , England (, Scotland , Canada , and Northern Ireland . Furthermore, a submission to inform a New South Wales (NSW) state health plan by a peak body indicated that the poor experiences and outcomes documented for people with intellectual disability are similarly experienced by those with other forms of disability . Mounting evidence in both the grey and published literature suggests continued and serious problems during hospitalisations for people with intellectual and other types of disability and those who support them.
This review was conducted in Australia where it is particularly timely to consider the research evidence about how hospitals may meet the needs of people with disabilities. Recently, the government called for reasonable adjustments by mainstream services, including health care, to ensure equality for people with disability . There is also a need to understand the nature and degree of adjustment required of hospital staff, and how these adjustments may contribute to hospital quality and safety performance . In Australia, policy directives to address the needs of people with disability in hospitals have been evident only in one state . These directives include reduced reliance on family and paid disability staff, and adjustments to pre- admission and discharge plans. Unfortunately, the NSW policy directive fails to compel services to make changes . Similarly, other policy and practice documents have failed to address the needs of people with disability, more broadly, during hospital encounters .
A number of reviews have explored underlying contributors to poor hospital experiences by people with intellectual disability ,-. These reviews have similarly revealed that some people with intellectual disability are fearful of hospital encounters, there is reliance on carers during the entirety of stays, and problem attitudes and limited knowledge of hospital staff, sometimes with dire outcomes. Recommendations to ameliorate problems identified in studies reviewed by Backer, Chapman and Mitchell  reflect those from the UK inquiry : that is, developing liaison models, especially through a disability liaison nurse, supporting carers, and improving communication. Mencap's  concern of little progress since these recommendations were published has been borne out in the literature, with little evidence, for example, of adopting the frequently recommended Learning Disability Liaison Nurse strategy .
Backer et al.  argued for further research into hospital access and experiences for people with intellectual disability, but there is little to indicate the value of or specific need for continued research. Previous reviews have focused on summarising findings of largely qualitative research, with little critique of their quality. Phillips , for example, noted the use of a critical appraisal tool, but reported methodological limitations of studies reviewed rather than providing quality scores. Bradbury-Jones et al.  used a dichotomised rating of weak or strong, but provided little in the way of rating criteria or reliability. Also, there has been no attempt to determine the extent to which studies have contributed specific and new information about the nature and points of hospital encounters that may present particular challenges in meeting the needs of patients with disability. Hospital encounters, or points of encounter refer to specific points on the patient’s journey through a hospitalisation, such as admission, diagnostic testing, placement on a ward, and discharge. Recommendations for adequate assessment of needs and discharge planning  fail to take into account the many points of encounter with staff filling varied roles, or of patient requirements as they engage in the journey from presentation to and exit from hospitals.
Prior to undertaking further research into hospital experiences, in general, a critical quality review and analysis of the points of hospital encounters are needed. Such a review promises insights into barriers and enablers of reasonable adjustments by hospital services across the patient journey. It would also provide direction for further research to ensure quality hospital care for people with intellectual disability and others made vulnerable by reliance on others for care and advocacy.
The review addressed the issue of how the hospital system responds to adults with intellectual disability, their families and carers as reported in current research. Specific aims were to (a) understand the experiences of adults with intellectual disability using hospital systems and the views of their families and paid carers; (b) understand the experiences of hospital staff who provide care for people with intellectual disability in hospital; and (c) evaluate the quality of the research and identify gaps in the literature, in particular in terms of the types of interactions and points of encounter along the patient journey.