If a major shake-up in the way new medicines are approved can give Scotland a truly world-leading system, that is clearly welcome.

But it has to be a cautious welcome.

Claims yesterday that 1500 patients will benefit in the first year of the new scheme are only half of the equation.

The figure is based on the argument that this number of people could secure access to newly licensed medicines within 12 months of a policy change to be introduced by the Scottish Medicines Consortium (SMC) in May.

That will replace the previous unloved system whereby the SMC's guidelines appeared to restrict access by patients to new drugs which might help them fight rare conditions and life-limiting illnesses. Patients cannot understand why valued and apparently effective treatments are not always immediately made available.

But for every high-profile new drug there are other treatments, other priorities, that have to be balanced against immediate endorsement. NHS budgets are not bottomless and the job the SMC has done, often more promptly and efficiently than its counterpart, The National Institute for Clinical Excellence south of the Border, is to manage those difficult choices.

The balancing half of the equation, on the other side from those 1500 beneficiaries, is the patients with perhaps less emotive conditions - the pensioner waiting for a cataract operation or a hip replacement. Wheelchairs for children are still in short supply in parts of the country.

How do you weigh the needs of a terminally ill father who, if given an expensive drug, may have an extra three months with his family, against the cheaper hip operation which might give hundreds of patients many years more of active living?

So is there a sense that Health Secretary Alex Neil is being a little glib when he says simply that SMC decisions should better reflect the views of patients. Important decisions about the approval of medicines, Mr Neil says, "can only be made by those living with these conditions and our clinical experts". But which patients and which experts?

If new medicines are more likely to be approved, as Mr Neil and the SMC claim, how will the cost be met?

The Health Secretary says expanding the use of generic medicines and shorter stays in hospital for the recipients of the new drugs will cut costs. Neither of those savings seems entirely a given.

Yes, attempts to democratise the NHS are welcome. While the public were less than enthralled by the prospect of directly elected health boards, public engagement with decisions about new medications is high. Giving patients a say in which drugs are approved has plain benefits in terms of transparency.

But this voice should not be extended simply to those who will benefit from the new treatments. Other NHS patients ultimately risk bearing the cost of very expensive treatments in developing areas of health care. It is vital that these patients also have a say. If their views and their needs are to be taken into account, they must not be invisible in this new system.