Patricia Day and Rudolf Klein, in their article 'Privates on parade' (features, pages 20-22, 23 September), make a good case for a different approach to the regulation of independent healthcare, but such regulation needs to extend well beyond the limited range of acute hospital services to which they devote the thrust of their argument.

Using the independent sector is not always, as Ms Day and Professor Klein assert, 'an act of free choice'. Some 24 per cent of all acute psychiatric care is provided by the independent sector.

This is not inspected by the Mental Health Act Commission because, as amply demonstrated in the Ashworth inquiry, the commission is not an inspectorate - it is primarily concerned with the operation of the Mental Health Act and the treatment of detained patients which, as the Ashworth committee of inquiry accepted, 'limits the extent to which the commission can be involved in organisational and managerial issues'.

As for the future, all categories of mental health treatment and care, including that for people with acquired brain injury, hospices, private primary care, invasive procedures outside hospitals, nursing agencies, laser and hyperbaric therapy, are among activities which, at the moment, have not secured a future regulatory home.

The cost-effective solution would be to create divisions of healthcare regulation in the proposed commissions for care standards, capable of providing the specialist oversight of all categories of healthcare from acute to that provided in social care settings - with the status and authority to recognise that differential levels of inspection can apply to individual circumstances of provision and quality.

The work of the Commission for Health Improvement can inform such regulatory activity but it cannot replace it.

Chris Vellenoweth Independent adviser on health policy Wirral