Statewide surveillance of occupational injury hospitalizations in Maryland: Benefits of data linkage

We sought to develop and evaluate model surveillance systems for hospitalized occupational injuries. Data linkage using probabilistic linkage techniques identified hospitalized work-related injuries in Maryland, using indicators of work-relatedness in hospital records, EMS reports, autopsy records, death certificates, and police reports to create incident-specific records for 2001-2004. Validation studies examined agreement between sources and reviewed charts. Hospital payor source Workers' Compensation (WC) identified 4.5% of injury admissions as work-related, increasing to 5.3% after linkage (19% increases in counts and rates). WC identified 77%, with a further 6% identified with industrial place of occurrence. Place of occurrence as farm, only identified 56 additional cases. Falls from 15 or more feet from EMS data, brought in an additional 5%. Finally, trauma registry linkage added 6 %( the most severe of the injuries requiring hospitalization). Identification of work-related injuries due to motor vehicle crashes was relatively low. Using police reported data on drivers of commercial vehicles as the “gold” standard 65% of the inpatient data gave an indication that injuries were work-related. Chart review of sentinel injuries suggest that even with our data linkage, there is still considerable under-reporting of work-relatedness using available data. Further examination of the fall reporting by EMS seems to indicate that it may not be specific enough to indicate work-related injuries, especially in the extremes of age. This is the first US study to attempt to use available data to estimate population-based work-related injury hospitalizations. Data linkage is a useful tool for surveillance of serious occupational injuries.