Mary Scanlon: Author of the committee report

The group's report has been delayed amid speculation of a split between those wanting to recommend the triple vaccine and those who think separate injections are preferable.

However, this was denied by an executive spokesman who blamed the delay on the need to get evidence "from as wide a range as possible".

The expert group was set up last year following a recommendation by the Scottish Parliament's health committee.

The committee found no proven scientific link between the vaccine and the condition - but said it had concerns it wanted addressed.

Its report was written by Conservative health spokeswoman Mary Scanlon, who said there were concerns that a drop in vaccinations could lead to a measles outbreak.

Register of interests

"We don't need any uncertainty cast over the decision of this group, and I'm afraid the financial links with pharmaceutical companies have done that," she said.

According to the register of interests, group members Professor Eve Johnstone, Dr Andrew Riley and Professor Lewis Ritchie all have financial interests in GlaxoSmithKline.

The firm is one of the makers of the controversial MMR triple vaccine, which research has linked to autism and bowel disease in children.

A fourth member, Dr David Goldblatt, has also received support from a number of firms that manufacture vaccines.

However, Health Minister Malcolm Chisholm said "nothing new" had been revealed.

It is wholly irresponsible to cast doubt over the work of an 18-strong expert group on the basis of four declarations of interest

Scottish Executive spokesman

"The group includes a wide range of people, including parents of people with autism.

"Nobody objected at the first meeting and the information was put on the website," he said.

A spokesman for the executive added: "We are confident that the expert group, drawn from a wide range of medical and parental interests, is the right one to fulfil its remit.

"We are, however, very concerned that there appear to be attempts to undermine the group's impartiality and the legitimacy of its report in advance of publication."

The spokesman said a declaration of interests was "very different" from a conflict of interests.

"It is wholly irresponsible to cast doubt over the work of an 18-strong expert group on the basis of four declarations of interest," he said.

"We fully expect the report to be balanced and objective and to reflect the views of the expert group as a whole - a group which includes parents with autistic children."