The former head of the NHS, Nigel Crisp, has attacked private health insurers for their policies, which he claims are arbitrary and sometimes leave patients with cancer without the care they need.

Lord Crisp said that private health insurance policies had a worrying lack of transparency, which was creating a “private healthcare lottery.”

But representatives for the industry have rejected the claim, saying that private health insurance works well and that companies often consulted the public to ensure transparency in their policies.

Speaking during a House of Lords debate on 11 November on measures to improve the quality and quantity of life of people with cancer, Lord Crisp called on the Financial Services Authority …