Population-based asbestosis surveillance in British Columbia.

OBJECTIVES

To investigate the use of multiple health data sources for population-based asbestosis surveillance in British Columbia, Canada.

METHODS

Provincial health insurance registration records, workers' compensation records, hospitalisation records, and outpatient medical service records were linked using individual-specific study identifiers. The study population was restricted to individuals > or = 15 years of age living in the province during 1992-2004.

RESULTS

1170 new asbestosis cases were identified from 1992 to 2004 for an overall incidence rate of 2.82 (men: 5.48, women: 0.23) per 100,000 population; 96% of cases were male and average (SD) age was 69 (10) years. Although the annual number of new cases increased by 30% during the surveillance period (beta = 2.36, p = 0.019), the observed increase in annual incidence rates was not significant (beta = 0.02, p = 0.398). Workers' compensation, hospitalisation and outpatient databases identified 23%, 48% and 50% of the total new cases, respectively. Of the new cases, 82% were identified through single data sources, 10% were only recorded in the workers' compensation records, and 36% only in each of the hospitalisation and outpatient records. 84% of hospitalisation cases and 83% of outpatient cases were not included in the workers' compensation records. The three data sources showed different temporal trends in the annual number of new cases and annual incidence rates.

CONCLUSIONS

Single data sources were not sufficient to identify all new cases, thus leading to serious underestimations of the true burden of asbestosis. Integrating multiple health data sources could provide a more complete picture in population-based surveillance of asbestosis and other occupational diseases.