BackgroundThere has been consistent evidence that people with learning disabilities experience health inequalities and poor NHS health-care provision, leading to avoidable harm and premature, avoidable death.ObjectivesTo describe the factors in NHS hospitals that promote or compromise a safe environment for patients with learning disabilities, in the light of national recommendations that hospitals should (1) identify patients with learning disabilities, (2) provide reasonably adjusted services, (3) involve carers as partners in care and (4) include patient and carer views in service development.DesignA 21-month mixed-method study carried out between 2011 and 2013, using questionnaire surveys, interviews, observation and monitoring of safety incidents.SettingSix NHS hospitals in the south of England.MethodsThe study employed mixed methodologies in three stages. Stage I involved mapping the systems and structural changes within each hospital site, with senior strategic managers asked to provide data on relevant policies. Stage II examined the effectiveness of implemented measures. Methods for this stage included an electronic questionnaire survey sent to all clinical staff (n = 990); face-to-face semi-structured interviews with clinical staff and strategic hospital managers (n = 68); semi-structured face-to-face interviews with adults with learning disabilities who had used the hospital in a 12-month period (n = 33); questionnaire survey (n = 88) and semi-structured interviews (n = 37) with carers of patients with learning disabilities who had been a patient during the 12-month period; and participant observation with patients (n = 8). Stage III assessed generalisability to other vulnerable patient groups and involved expert panel discussions with senior managers and senior clinicians at four sites (n = 42).ResultsExamples of good practice were not consistently replicated hospital-wide. The most common safety issues were delays and omissions of treatment and basic care. The main barriers to better and safer hospital care for people with learning disabilities were (1) the invisibility of patients with learning disabilities within hospitals, owing to a lack of effective flagging systems and a lack of staff knowledge and willingness to flag this group; (2) poor staff understanding of the specific vulnerabilities of people with learning disabilities, the reasonable adjustments to services that these patients may need and the Mental Capacity Act (Great Britain.Mental Capacity Act 2005. Chapter 9. London: The Stationery Office; 2005); (3) a lack of consistent and effective carer involvement and misunderstanding by staff of the carer role; and (4) a lack of clear lines of responsibility and accountability for the care of each patient with learning disabilities. The main enablers were the learning disability liaison nurse (LDLN), provided that this role was properly supported by senior management and carried sufficient authority to change practice; and ward managers who facilitated a positive ward culture and ensured consistent implementation of reasonable adjustments.ConclusionsThe vulnerabilities of people with learning disabilities can, and do, lead to compromised patient safety in NHS hospitals. Further research is needed as follows: (1) identifying the most frequently needed reasonable adjustments within the hospital care pathways of people with learning disabilities and their cost implications; (2) identifying the most effective structures for ensuring clear lines of responsibility and accountability for the care of patients with learning disabilities, including support needed by ward managers in order to carry day-to-day accountability; (3) investigating practical and effective ways of flagging patients with learning disabilities across NHS services and within NHS hospitals; (4) investigating, implementing and evaluating protocols for shared care; (5) evaluating LDLN posts nationwide; and (6) extending research recommendations (1) and (3) to patients with dementia and those with mental health problems.Study registrationComprehensive Clinical Research Network Portfolio, 10998; Integrated Research Application System Coordinated System for gaining NHS Permission, 74907.FundingThe National Institute for Health Research Health Services and Delivery Research programme.