More than 100 health records - almost half of them in NHS Grampian - went missing in Scotland last year.
The 104 files included personal details of children and sensitive health information, according to details in a Freedom of Information response.
NHS Grampian insisted its 50 records were not "lost" but "reported missing".
However, the Scottish Liberal Democrats have called for a Scotland-wide investigation into the NHS management of patient records.
"The discovery of dumped patient files in Dundee last week was appalling," said Lib Dem health spokeswoman Alison McInnes.
"Extremely personal information, detailing illnesses, treatments and even addresses of 22 patients, had been discarded next to a publicly-used bin and left for anyone to see.
"This incident on its own should be cause for the health secretary to investigate what the NHS is doing to protect patient records."
The misplaced Grampian records included clinical notes, nursing records, a neonatal record and a drug report.
NHS Highland lost 17 records, including 14 from children's services, largely relating to requests for records from another health board when a child moved into the area.
NHS Lanarkshire lost 22 records containing personal details, assessment information and one x-ray.
NHS Forth Valley and Greater Glasgow and Clyde lost two records each, while NHS Tayside lost one.
NHS Lothian said it did not keep a record of lost files but said it was "not aware of any records being lost in the last year".
The figures were released after a Freedom of Information request by the Lib Dems.
"We have no choice but to trust health boards with our personal information," added Ms McInnes.
"It is simply not good enough for the health secretary to have a firm word with each health board in question and then move on."
A Scottish government spokesperson stressed that it took the confidentiality of patient data very seriously and that any data breach was completely unacceptable.
"That is why we have the Code of Practice that makes clear to all staff, students, volunteers and contractors their confidentiality obligations when working in, or with, NHS Scotland," she said.
"In addition, the Scottish government has already set out a clear programme of development activity in its Information Assurance Strategy to help improve information handling in the NHS in Scotland."