Mr. Lakshmi Narayanan,
Lab reports are also available inexpensively. The diagnosis of an illness can only be made by a doctor, who may recommend lab tests to determine the cause and severity of the sickness. Common symptoms like fever, body pain, or joint sprains cannot be identified through lab reports alone. Therefore, both a doctor's prescription and a lab report are necessary for an extended leave of absence. In this context, the author did not mention the reasons behind emphasizing the importance of lab reports.