NHS Lothian stood condemned last week for offering patients unrealistic appointments for procedures in England and using refusal to bump patients to the back of the queue.
Two senior officials have been disciplined following a report by outside consultants and Health Secretary Nicola Sturgeon was forced to apologise to the Scottish Parliament.
But Labour now says fresh evidence that numerous health boards had been warned about their use of waiting lists adds "considerable weight" to calls for a Scotland-wide probe into a hidden waiting list scandal.
Citing a spokesman for the Information Services Division who said several health boards had been warned about "high levels of social unavailability", Labour said there has been an unexplained increase in this by 200% in recent years.
It means either people are taking more and longer holidays or finding other reasons to turn down appointments, or boards are deliberately offering less suitable choices.
Shadow Health Secretary Jackie Baillie said: "Scottish Labour has been warning Nicola Sturgeon about this since 2008, and now it would seem we were not the only ones. Warnings seem to have fallen on deaf ears time and time again."
Labour has also called for urgent action to improve treatment for chronic pain patients after a study revealed almost 2000 patients are stuck on waiting lists for treatment.
Findings from Freedom of Information requests revealed that across Scotland more than 1866 patients were awaiting their first appointment, while 1000 were awaiting their second.
The longest wait was Shetland (33 weeks), followed by Grampian (30) and Lothian (22).
A Scottish Government spokeswoman said last night: "Across Scotland, the clear majority of patients are treated within waiting time targets and waiting times are overall the shortest they have ever been."