Incidence of sickness certification. Proposal for use as a health status indicator.

Cause-, sex-, and age-specific incidences of sickness certification in a total population are reported. The population at risk of having a sickness certificate issued was 106,019 employed persons 16-69 years of age. The annual incidence of sickness certification was estimated at 580 per 1,000 employed persons per year (females 596, males 568). The most frequent causes of sickness certification, according to diagnostic groups, were diseases of the respiratory system, musculoskeletal/connective tissue diseases, mental disorders, and injuries. Adjusted for age, injuries were found to be less frequent causes of sickness certification among females than males (p less than 0.001), while the reverse was true for mental disorders (p less than 0.01). Among single diagnoses, "other nonarticular rheumatism" (including myalgia) was more frequent among females than males, while the opposite was true for "backpain without radiating symptoms" (p less than 0.001). Comparisons with morbidity studies indicate that diagnoses stated on initial certificates, issued to employed persons in the total population, give a reflection of a population's health problems. This suggests that sickness certification may provide a basis for a health status indicator which may prove useful in planning and evaluation of occupational health, general practice, and community health.