The degree of disability does not correlate directly with the medical diagnosis; it is multicausal. Entitlement to a benefit is determined on the basis of legal criteria, and the diagnosis is not leading in this respect. The scheme focuses on what a person is capable of doing, which may vary for people with the same diagnosis depending on age, sex, education, nature of work and other factors.
All cases include a main medical diagnosis, as declared by a social security physician. But this is not necessarily the only cause for the non-ability to work; often, more than one diagnosis is possible, and which is taken as the main diagnosis is determined on a fairly arbitrary basis.
The classification used for health and safety inspectors and social insurance schemes includes:
1) Classification of symptoms
2) Classification of diseases
3) Classification of causes
Since 1998 the Classification of diseases is used, based on the ICD-10 (the International Classification of Diseases) which was declared as the Dutch standard by the government in 1994.