The number and composition of people working in hospitals in OECD countries varies depending on the roles and functions that hospitals play in health systems, as well as on how different types of support services in hospitals are provided and accounted for. The roles and functions of hospitals vary notably regarding the extent to which outpatient specialist services are provided in hospitals or outside hospitals. In most countries with universal health coverage funded by the tax system (national health service‑type systems), outpatient specialist services are typically provided in public hospitals. This is the case, for example, in the United Kingdom, Nordic countries, Portugal and Spain. In other countries such as Australia, Austria, Belgium, Canada, France, Germany, Switzerland and the United States, most outpatient services are provided outside hospitals. In some central and eastern European countries (such as Estonia and Slovenia), most outpatient specialist services are provided in public hospitals, whereas these are provided in public multi-specialty clinics in others (such as Poland) or in private solo practices (as in the Czech Republic).