Creatinine levels relate to both muscle mass and to kidney function. As you age, your muscle mass decreases but your kidneys tend to function less effectively. The net result is not much change in creatinine levels in the blood as you get older.
As a result, California employers are required by law to have workers' compensation insurance, even if they have only one employee. And, if your employees get hurt or sick because of work, you are required to pay for workers' compensation benefits.
If the employee obtains no medical care, or obtains only agency-sponsored care on the date of injury, and no time loss is charged to either leave or continuation of pay, the supervisor should place Form CA-1 in the worker's Employee Medical Folder (EMF) instead of sending it to OWCP.