The occupational history can be used on four levels:  Basic—knowledge of the patient’s current occupation and industry, and implications of the present illness for employment  Diagnostic—investigate an association with the present illness, for compensation considerations  Screening—individual surveillance  Comprehensive—investigate complex problems in depth, usually in consultation with other occupational health professionals If you decide that a detailed (comprehensive) occupational history is not necessary, it is still important to obtain the simple, basic, and screening occupational histories on all patients to help determine job type and potential exposures.