The lack of women and ethnic minorities in senior roles within the NHS has been branded "disgraceful" and a "serious weakness" in the health service.
Just 2% of NHS trusts are chaired by people from a black and minority ethnic (BME) background, while under 30% of trusts are chaired by women, a report showed.
There must now be a "radical transformation" to redress the balance, the study, entitled Action not words - Making NHS boards more representative, said.
Shadow health minister Lord Hunt told the Guardian: "The lack of women chairs is bad enough. But the BME proportions are disgraceful."
He added: "Too many chairmen want to appoint executives who are in their own image."
The report looked at information from around 1,450 board members at 114 trusts, the newspaper said.
Findings showed three-quarters of those chairing NHS trusts are aged 60 or older, less than half of trust executive directors are female, and a mere 4% of executive directors are from a BME background.
The report said: "This is a serious weakness which needs to be rectified as a matter of priority.
"Good intentions and platitudes are not sufficient. There is a clear need for the Government to step in and insist that NHS trust boards undertake a radical transformation to reflect the communities they serve."