This is just one of more than 800 incidents of data loss by Scottish health boards in the last five years, new figures have revealed.
The folder with patients' personal details was discovered in July 2013 by a member of the public who handed it to a nearby hospital.
The previous month letters relating to a patient were found in NHS-GGC hospital grounds.
Figures obtained by the Scottish Liberal Democrats, through Freedom of Information requests, show patient notes being found in public places within NHS buildings, documents left in car parks and on public transport, and personal information being sent to the wrong address.
They detail 806 incidents of data loss, leaks or Data Protection Act breaches in Scotland's health boards between 2009 and 2013.
In another incident, at NHS Dumfries and Galloway in October 2011, X-rays were found in one patient's records which did not belong to them.
The Scottish LibDems have called on the Scottish Government to ensure that NHS Boards are given adequate support to protect confidential patient information.
The Scottish Government said it takes patient confidentiality very seriously and believes any data breach is unacceptable.
A spokeswoman said all mobile devices holding patient data are now encrypted.
An NHSGGC spokeswoman said: "With many millions of patient data transfers between departments and health professionals every year we take our responsibilities towards data protection extremely seriously. On the rare occasion when a loss of data has occurred, these have been fully investigated."