The Commons health committee has strongly criticised the government’s approach to NHS reform - particularly its “surprise” announcement of the abolition of primary care trusts and strategic health authorities.

The committee, chaired by former Conservative health secretary Stephen Dorrell, publishes its report into health commissioning today.

Referring to the “already high-risk” task of making up to £20bn efficiency savings in the NHS over three years, the report says the “white paper increased the level of risk considerably without setting out a credible plan for mitigating that risk”.

The report says: “The [July] white paper proposes a disruptive reorganisation of the institutional structure of the NHS which was subject to little prior discussion and not foreshadowed in the Coalition Programme [the coalition agreement in May].

“While such a ‘surprise’ approach is not necessarily wrong, it does increase the level of risk involved in policy implementation.

“There appears to have been insufficient detail about methods and structures during the transitional phase.”

The committee said it was concerned the disruption was already causing some bad commissioning decisions, for example limiting apparently clinically justified referrals.

Mr Dorrell said the approach had pushed up costs and risks of the change. He said: “There has been a period of instability that has resulted in costs. The transitional costs are almost certainly higher that they would have needed to have been.

“There are examples of decisions by commissioners that don’t reflect clinical commissioners.“

The report praises the “pragmatic response” of the Department of Health in ordering PCTs to form clusters. It says the deadline to form clusters should be April instead of June as at present.

The committee is planning a further inquiry to inform the health and social care bill, which will be published on Wednesday, as it passes through Parliament. Issues it said it will focus on include how the NHS commissioning board with performance manage consortia; the relationship between the board, DH and health secretary; how consortia engage other clinicians; and how reforms will allow integration.

Mr Dorrell first dubbed the £20bn efficiency savings as the “Nicholson challenge” - after NHS chief executive Sir David Nicholson - in an interview with HSJ in November.

Launching the report, Mr Dorrell said: “The yardstick by which these reforms need to be judged is their effect on the ability to deliver the Nicholson challenge.”