Transport problems could be costing the health service in Northern Ireland up to £2.2 million a year, it was claimed.
Hundreds of people have missed or been forced to cancel hospital appointments because they had no way of getting there, according to a new study by the Consumer Council and Patient and Client Council.
"This report shows that missed appointments not only impact on people's well-being, they also have a significant financial impact on our health and social care services.
"One solution to this problem has to be greater joined up working with the relevant bodies and more inclusion of travel information with patient appointment letters," said Maeve Hully, chief executive of the Patient and Client Council and Antoinette McKeown, chief executive of the Consumer Council in a joint statement.
Anxieties over spiralling fuel and parking costs impacted on those taking a car to medical appointments.
Those relying on public transport found difficulty co-ordinating with bus and rail timetables. They also found the distance from stops to health centres and hospitals exacerbated their problems.
The report recommends that the health, roads and rural development departments at Stormont devise a co-ordinated strategic approach to transport and health and social care.
It has also called for the five health trusts should also review the operation of the Hospital Travel Costs Scheme and for Translink, which operates the public transport network in Northern Ireland, to meet regularly with the relevant health bodies.
"The Consumer Council and Patient and Client Council will continue to work together to address the issues raised in this report and seek improvements to transport access to health and social care services to reduce the personal and financial cost of missed appointments," the statement added.