A system should be used where building a database with a large number of files that contain relatively little information is possible and can be managed. Paper files can be in a last name alphabetic order, but a lot of names duplicate or are difficult to classify like that, the date of birth is often not known or not accurate. A file by ship’s name may be effective but then the person has to remember the name of the ship he was on when he last visited the clinic when he comes back. A combination of all elements with an electronic file on name, first name, sex and date of birth, combined with a paper classification system on ship’s name and year of visit is most effective. Electronic files have the advantage of being portable and allow population analyses on a relatively easy basis. The information should therefore be stored in a standardized way and maritime physicians are to be encouraged to use codes e.g. ICD10 or ICPC to summarise their assessment or diagnosis of a case.