Only one area, Tayside, consistently recorded at least 98 per cent of people being seen within four hours, according to official figures for the first three months of this year.
Five of the country’s 14 boards hit the benchmark in March.
The update comes weeks after an Audit Scotland report prompted concerns about the length of time patients were being forced to wait in A&E. The latest figures showed 93.3 per cent of patients were seen within the target in March, down from 93.5 per cent in December.
NHS Greater Glasgow and Clyde had the lowest compliance at 89.6 per cent, followed by NHS Lothian with 92.2 per cent.
A second, lower target of 95 per cent – set up in an attempt to drive forward improvements – was also missed by four boards in March.
Health secretary Alex Neil said there were added pressures on the NHS during winter.
“Of course we want to see more improvements, which is why the Scottish Government will continue to work with those health boards that need to deliver improvement,” he said.
“There is no question that our NHS is making sustainable progress towards delivery of the milestone target of 95 per cent.
“In March this year, despite demand in A&E increasing by 6 per cent compared to last March, the proportion of patients treated within four hours increased from 91.9 to 93.3 per cent.”
Audit Scotland revealed that about 104,000 people waited beyond the standard four-hour target in 2012-13, compared with about 36,000 in 2008-9.
In the 12 months to March this year, the total was 99,314, according to the new NHS figures.
Scottish Labour MSP Neil Findlay said: “These figures again show that the SNP’s target is nothing but a fantasy.
“Even when the SNP reduced the target, it still isn’t being met in the majority of health boards.
“Audit Scotland told the Scottish Government that our hospitals simply can’t cope with the demands being placed upon them. These figures show that nothing has changed.”
Scottish Conservative health spokesman Jackson Carlaw said the government was “miles away” from its target.
“This is a Scottish Government that is completely obsessed with the independence referendum, and its fascination with that is coming at the cost of performance in our hospitals,” he said. “Instead of constantly comparing our NHS to other places in the UK, it’s time Alex Salmond focused on the performance here.”
Scottish Liberal Democrat health spokesman Jim Hume added: “Our hardworking NHS staff and hospitals are being forced to use sticking plasters to fix a much deeper problem.
“Audit Scotland, the Royal College of Nursing and the former president of the Royal College of Physicians in Edinburgh have made clear that hospitals are struggling to cope with demand.”