Hospice services are based on the notion of alleviating pain and increasing the quality of life for people with terminal illnesses or elderly people near the end of their lives. In the US, the majority of hospice patients are the elderly, but people of all ages can qualify including children. Medicare pays the largest percentage of hospice expenses due to the high elderly demographic, but Medicaid and private insurance companies also have provisions for hospice care.
The main requirement for hospice care in the US is certification from two different physicians that the patient in question has six months or less to live if their condition continues as expected. People can remain in hospice care for more than six months if the situation arises and is deemed necessary.
In terms of barriers, there are two primary barriers, money and social stigma. In terms of finances, hospice care in the US does cost money. Since Medicare and Medicaid (and many private insurance carriers for the non-elderly) pay for hospice, most elderly are potentially covered. But those in the US not under these programs would find the cost prohibitive. Since hospice does not generally include a lot of expensive medical intervention, there is little financial incentive from the point of view of health care providers for people to be transferred to hospice. On the flip side, hospice centers can be very selective in accepting patients, often waiting until they are at the very end of their lives. This is because if a person stays on hospice for more than 6 months, insurance providers (including Medicare) become more aggressive in auditing the hospice provider to make sure that there is not a pattern of fraud.
The other barrier is a social stigma. Some people do not view hospice as true medicine since the purpose of it is not to cure but to alleviate pain until death. Some view it as accepting death as a form of extended suicide. This obviously comes down to personal philosophies and personal choices for what people feel is right for themselves or their family members.