title: Mapping the knowledge base for maritime health: 2. a framework for analysis.
abstract: The knowledge base for maritime health has a number of constant features that have become apparent over  the last 150 years. These can be used to structure an analysis of the current state of knowledge and to identify  where there is sound evidence about the nature and scale of risks and about the effectiveness of intervention  to reduce harm. It can also show where there are deficiencies in knowledge and point to the ways in which  these could be remedied. Past events, as discussed in the first article, also indicate the dynamics of the political,  economic and human interactions that are central to improving knowledge and to its application to improve  the health of seafarers.  The sources of useful knowledge about seafarer's health range from single case reports of an unusual disease  to long-term studies of common chronic disease incidence. The most accessible events to record are clinically  apparent illness, injury, or cause of death, but active investigative studies may look at risks in the environment,  personal risk factors, or pre-clinical phases of disease.  Comparisons between subsets of a population are needed to look rigorously at health risks or at the effectiveness  of intervention. This is best done if information on the at risk population can be used as the basis for  deriving the incidence or prevalence of illness and if the populations compared are as similar as possible in  every way, except that being studied. Sometimes large studies in onshore populations can provide information  that it is not feasible to collect on seafarers.  Information on seafarers' health can be collected in several settings: at sea, on arrival in port, during  leave periods, or after retirement. For acute illness and for injury a single setting can provide the basis for  estimating risks, but for chronic conditions cases arising in several settings have to be included and the at  risk population calculated to enable the incidence to be studied.  Knowledge about the health of seafarers can be used to improve prevention both by attention to the  conditions of living and working at sea and by selection of seafarers who are considered 'fit' for work. It is  also important for defining the needs for emergency care at sea and in port. The overall patterns of illness  and injury in seafarers and how these compare with other workers are important inputs to regulatory  decisions on the measures to be taken to reduce harm from illness and injury. Markers of improved  seafarer health can confirm the effectiveness of measures taken with this goal in mind.  Reducing the contribution of health-related impairment to accidents and other risks at sea requires knowledge  of the effects of such impairments on performance and safety in the routine and emergency tasks  of a seafarer. This information can then be used to determine whether someone with an impairment can  safely work at sea.
authors.affiliation: Norwegian Centre for Maritime Medicine, Department of Occupational Medicine, Haukeland University Hospital, University of Bergen, Bergen, Norway. Tim.carter@mcga.gov.uk
authors.forename: Tim
authors.initials: T
authors.lastname: Carter
mesh_terms: D055317:Evidence-Based Practice; D014943:Global Health; D007722:Health Knowledge, Attitudes, Practice; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D033181:Information Dissemination / Q000379:methods; D051188:Knowledge Bases; D009784:Occupational Diseases / Q000453:epidemiology; D016272:Occupational Health / Q000266:history*; D009792:Oceans and Seas; D010807:Physical Endurance; D018570:Risk Assessment / Q000379:methods; D012767:Ships; D014938:Work Capacity Evaluation