April will see the expansion of primary care trusts, heralding a shower of mergers across trusts and primary care groups. But That is not all: also on the agenda are a new concentration of acute trusts and the conversion of many GPs to personal medical se

No-one can fail to have noticed that the NHS very often carries out major changes on April fool's day. And for many managers, caught up in the latest game of musical chairs or trying to implement a minister's pet project, it must feel like the joke is on them.

This 1 April may not see the introduction of new structures across the board, but the massive expansion in the numbers of primary care trusts, the further concentration of NHS trusts, and the conversion of many GPs to personal medical services contracts make the date one more landmark for a changing NHS.

Perhaps most dramatically, 122 new PCTs will start work on 1 April, compared with around 40 already operating. 'It is going to create an enormous amount of change, ' says Dr Michael Dixon, chair of the NHS Alliance. 'And in over half of these cases the chief executive will be different from the chief executive of the PCG. '

In some cases, former PCG lay members have not been appointed as non-executive board members, and GPs who have taken a leading role in PCGs have been reluctant to offer the same input to PCTs.

NHS Confederation policy director Nigel Edwards sounds a note of caution that the aim of the reforms - a better framework for primary care, improved commissioning and ultimately better health outcomes - should not get lost in the structural changes.

Dr Dixon agrees: 'They must be a totally new idea which brings together people, and where the non-executives are people's champions. '

He also points to new ways of working between clinicians, managers and lay people which have developed in PCGs and ought to be carried through to the new PCTs. 'The great fear is that they may get stuck in the mud like every other health institution since 1948, ' he warns.

Dr Steve Gillam, director of primary care programmes at the King's Fund, adds: 'There is a strong sense that PCGs are almost reluctantly going forward. They'd have liked more time to build on their achievements as PCGs. '

One area in which PCTs have disappointed is commissioning.

Dr Dixon - who is in talks with the Department of Health on this - points to how national priorities are swallowing up funds, leaving very little to PCTs' discretion.

As one of the main thrusts of PCTs has been to move services closer to the communities they serve, and in the long term to switch resources away from acute hospitals towards more local solutions, this is a pressing issue.

PCTs are also covering wider areas than the PCGs they replace, often up to 250,000 people, with many coming out of the merger of two neighbouring PCGs. One strength of PCGs was their base in local communities and there are fears they will lose their local sensitivity as their size and complexity increases.

The widespread conversion of GPs to PMS in April may have even greater impact. GPs have been wedded to the complex general medical services system for many years. PMS sweeps this away, with some GPs becoming salaried - increasingly to PCTs - while others remain as independent contractors but within a fixed budget.

Until now the number of GPs in PMS pilots has been quite small - around 9 per cent. Those joining in April will swell this figure considerably. In December the government said it had 1,231 schemes which had registered an interest, but the British Medical Association argues that many GPs would have decided not to go ahead once they had considered the pros and cons of PMS. If all the proposed schemes proceed, 20 per cent of GPs will be working under PMS.

The government expects that to swell to a third of GPs by 2002 and half by the end of 2004.

The BMA, in particular, has been worried this will destabilise the centrally determined GMS as GPs negotiate deals locally, with a national core contract. Salaried GP posts - attractive to newly qualified GPs - may make it hard to recruit new GMS principals.

Dr Gillam says there is little evidence yet on how effective PMS is.

It may be improving access for hard-to-reach groups, but it is not known whether it is delivering care of comparable quality to the traditional model. 'But in terms of instilling the idea that we can do things differently, PMS is obviously very important, ' he adds.

As both PCTs and PMS schemes proliferate, a crucial issue is how effectively they can be monitored.

Dr Gillam questions whether health authorities have the capacity to do this when so many schemes are going through at the same time. 'With PCTs, I am less confident that the system can pick up the failures - the people who really struggle. '

Much of the action may be in primary care this April - but secondary care trust mergers are grinding on. One of the biggest acute trust mergers is in Sheffield.

Northern General Hospital trust and Central Sheffield University Hospitals trust will now work as Sheffield Teaching Hospitals trust. The benefits should be improved services with common protocols and waiting lists.

But Mr Edwards believes enthusiasm for ever-bigger trusts may be cooling: 'Many people thought it would bring people together - but they are now looking at other methods of doing that. '

Very large trusts may have 400600 consultants, making it difficult for senior managers to know and monitor every bit of the trust's operations.

PCTs are also leading to changes.

Specialist mental health and learning disability trusts now cover big areas, as other community services are stripped out and brought under PCT control. In Nottinghamshire, one trust will provide mental health services not only to the county, but also to those in Rampton high-security hospital.

While PCTs can happily run most of a community trust's work - ranging from health visitors to local hospitals - some have been reluctant to take on mental health.

But Dr Dixon points out that this may be changing with some thirdwave trusts.

Dr Andrew McCulloch, senior policy adviser at the Sainsbury Centre, says different models of mental health provision may suit different areas. He has some concerns about specialist trusts' size and potential remoteness, but says acute trusts running mental health services are not the answer.

The days of combined trusts also seem to be numbered. Bassetlaw Hospital and Community Services trust was pressured on one side by a PCT wanting to take on some community services itself, and on the other by a proposed countywide mental health trust. With only 150,000 people in its catchment area, it was too small to be an acute stand-alone trust and is now merging its acute services with Doncaster Royal Infirmary and Montagu Hospital trust.

Though 1 April 2001 may not stand out in the national consciousness like 5 July 1948, for those involved in the changes it will be a date to remember.

Those new trusts in full Buckinghamshire Mental Health trust; Hertfordshire Partnerships trust; North and East Devon Partnerships trust;

North Cheshire Hospitals trust; Berkshire Healthcare trust; Calderdale and Huddersfield trust; West Hampshire trust; Southern Derbyshire Community and Mental Health trust; Sherwood Forest Hospitals trust; North East London Mental Health trust; Barking, Havering and Redbridge Hospitals trust; Whipps Cross University Hospital trust; Nottinghamshire Healthcare trust; Sheffield Teaching Hospitals trust; Northern Lincolnshire and Goole Hospitals trust; West London Mental Health trust; North Cumbria Acute trust; North Cumbria Mental Health and Learning Disabilities trust; Newcastle, North Tyneside and Northumberland Mental Health Services trust;

Northamptonshire Healthcare trust; Doncaster and Bassetlaw Hospitals trust; Lincolnshire Healthcare trust; North Essex Mental Health Partnership trust; South Staffordshire Healthcare trust; Wrightington, Wigan and Leigh trust;

Barnet, Enfield and Haringey Mental Health trust; and Camden and Islington Mental Health trust.