Glossary

Haematopoeitic Stem Cell Transplantation

The time required for half the amount of a medicine to be eliminated from the body.

The endpoint of a clinical trial is a pre-defined event: for instance, the occurrence of a disease, the occurrence of a symptom, or a particular laboratory result. Once someone reaches the endpoint, they are generally excluded from further research in the trial.

A hard endpoint is an endpoint that is well defined and can be measured objectively. For example, in cancer research, the endpoint in a trial might be related to response to treatment (such as shrinkage of a tumour). Endpoints related to a response are typical in Phase II clinical trials for cancer treatments. Endpoints relating to the survival of patients are common in Phase III cancer trials. 'Progress free survival' and 'disease free survival' measure the length of time patients are alive without their disease worsening.

In contrast to hard endpoints, soft endpoints are subjective measures. Quality of life measures, for example, are soft endpoints. It is common to use quality of life measures as endpoints in Phase III trials. In this case, patients are asked specific questions about the impact of their disease and/or treatment.

The endpoints used in a trial must be defined and documented as part of the trial design.

French Health Technology Assessment body. http://www.has-sante.fr/"

A hazard ratio is a measure of how often a particular event happens in a defined period of time in one group compared to how often it happens in another group.

Heads of Medicines Agencies (HMA) http://www.hma.eu/"

A health event can be positive or negative. An example of a health event is the development of a disease, an injury, or responding to a medicine.

Irish National Competent Authority. https://www.hpra.ie/"

Health technology assessment aims to inform decision making by health care policy makers. It is a systematic process that considers health technologies (such as medicines) and can involve a review of:

• clinical evidence compared to existing models of care,
  
• cost effectiveness,
  
• social and ethical impacts on the health care system and the lives of patients.
  

The process advises whether or not a health technology should be used, and if so, how it is best used and which patients are most likely to benefit from it. Assessments vary, but most look at the health benefits and risks of using the technology. They can also look at costs and any other wider impacts that the technology may have on a population or on a society. They can also look at the relationship between costs and benefits and risks, and make determinations about value for money.