The tragedy of the commons

As outlined in the background section, the various health care systems of each Italian region, which are organised and funded depending upon the size of the local populations, can be considered as common-pool resources that each regional resident can utilise to ful󰎓l his or her health needs without problems. However, in the presence of di󰎎erences between regional health systems, individual rights to free treatment choice can cause the occurrence of regional patient migration, which may create imbalances for local health authorities, especially when accounting for obligations on cost reimbursements in favour of receiving regions. In fact, regions with only high levels of incoming patients could be a󰎎ected by overuse of resources if maximum capacity is reached, while regions with only high levels of outgoing patients could possess underused resources, without improvement opportunities and with cost obligations towards other regions.

First of all, the work of Olson (1965) on the logic of collective action can be associated with patient migration in a partially tangent manner. In his book, he described how members of an interest group, when driven by self-interest, can decide to free-ride on the action of others to receive the bene󰎓ts of a collective cause without contributing to it; this event tends to be absent in small groups but to become relevant as they enlarge, as the signi󰎓cance of individual contributions for group performance and the per-capita share of bene󰎓ts reduce as the total number of people in the group increases [37]. Bendor and Mookherjee (1987) contributed to these ideas by con󰎓rming that the problem cannot be solved neither through cooperation, which is unsustainable in large groups, nor through centralised solutions, which can become a󰎒icted by a number of problems (e.g. di󰎏cult development of e󰎎ective monitoring systems); instead, they proposed the organisation of interest groups within federal structures, which can enforce cooperation and eliminate free-riding through small groups that together form a larger group [8].

More importantly, the previous thoughts can relate the phenomenon to the theory about a concept known as the tragedy of the commons, primarily portrayed by Hardin (1968) when discussing the issue of overpopulation in a world with󰎓nite resources. In particular, it concerns the shared usage of a resource that is open to anyone; at 󰎓rst, the common use can continue to happen as various circumstances, such as those caused by nature, maintain an equilibrium over time; however, independent decisions made by rational individuals, who seek to maximise their own utilities by taking as much as possible from the resource while sharing the downsides with the others, will eventually lead to the collapse of the shared resource, which will not be able to sustain any sort of production of resource units for them anymore. A clear example the author made regarded the shared usage of an open pasture by various herdsmen; to maximise the individual bene󰎓t, each herdsman would add as much cattle as possible to the common pasture, so that eventual negative consequences caused by an overall overgrazing would be endured by all the herdsmen; over time, such a system will collapse, leading to ruin for every individual relying on it and causing a tragedy of that common [18].

The contributions provided by Ostrom (1990), that enquire about the presented con-cepts, provide further explanations on how individuals can collaborate in the presence of common resources. In her book, using examples of real communities where people cooperate to govern a shared resource, she suggested that neither a centralised solu-tion overseen by a state nor a privatisasolu-tion of the resource is able to sustain a common productive usage over the long term; for the former, the state would be prone to making errors on the organisation of the resource usage, while having issues with costs for mon-itoring individual behaviours and potential imperfect information; for the latter, dividing a resource between individuals through private rights could be prone to the occurrence of unfavourable random events against only some of its portions (e.g. rain not falling in certain areas of a privately divided soil, in which grass is supposed to grow for the nourishment of animals pasturing there) or to the need for sustaining additional costs that can be avoided when the resource is instead commonly used (e.g. insurance costs against these sorts of unfavourable random events). As an alternative solution to either the control of a central authority or complete privatisation, the author suggested that individuals in a community should make preliminary agreements before using a shared resource through a self-made binding contract, which balances the share of bene󰎓ts with the costs of enforcing them, while ensuring that the resource exploitation will not take place outside of the commonly agreed terms; being constructed by the users sharing a resource, the enforcement mechanisms and the conditions of the contract can be op-timally shaped upon the needs of the community, with opportunities for changes if the users demand the agreements to be updated. Many were the empirical examples that the author gave to provide evidence on the existence of self-organising communities over the world: commonly utilised lands in the village Törbel of Switzerland; shared terrains in three villages of Japan; collective exploitation of irrigation systems in some cities of Spain. Her distinction between di󰎎erent kinds of individuals in a community may also be helpful when discussing the design of policies to resolve the issue; appropriators are those that withdraw resource units from a common-pool resource; providers arrange its

provision; producers ensure the sustainability of the resource system in the long term.

Among these individuals, she recognised that some of them may act opportunistically when having the chance or if the bene󰎓ts largely exceed the costs, therefore delivering potential issues to consider when enquiring about the problem [38].

A theoretical model will overview the implications resulting from the development of regional patient migration over time, which are considered of signi󰎓cance importance since, as Malthus (1798) underlined, “a great emigration necessarily implies unhappiness of some kind or other in the country that is deserted” [27, 9]. In the discussion section, these concepts on the logic of collective action and the exploitation of shared resources will be applied to the entire aspects of the issue in manners that cohere with its nature, that is deemed to be rather unique, to provide rational and realistic policy suggestions.