The report, "Reflections by Sincere Doctors", is to be published as a book by Random House in October. Doctors talk of how a reference for an angioplasty can earn a doctor a kickback; of how doctors order CAT scans and MRIs that are not required; and of doctors referring patients to a clinic for electrocardiograms for the sake of the commission.

Dr Arun Gadre, who works with an NGO in Pune called Support for Advocacy and Training in Health Initiatives (Sathi), had the difficult task of getting doctors to open up on the horrific malpractices rampant in their profession.

"It took him a lot of time to persuade them to speak up. They were nervous about giving testimony on the greed and corruption that seem endemic, but they felt it had to come out in the open before anything could be done about it," says Sathi co-ordinator Dr Abhay Shukla.

Shukla says the report is significant because, while evidence of corruption has been building up for some years, it has come largely from social organisations, field studies or patient anecdotes.

"This is the first time doctors have blown the whistle," he says. "Normally doctors never speak against one another. Their testimony shows we are on the edge of a severe crisis requiring regulation."

Their testimonies suggest that private Indian hospitals have become so commercialised that maximising profit underpins every aspect of treatment.

One doctor said that in monthly meetings with the hospital chief executive, he used to be reprimanded for having only a 10 per cent "conversion rate" - how many outpatients are advised to undergo surgery.

"He told me the conversion rate should be 40 per cent and that unless I increase it, I will have to leave the hospital," says the doctor, who eventually left.

Also common are "sink tests", in which laboratories perform only a few of the tests that have been asked for by the doctor. Since they know the patient has no serious ailment and the tests are purely a money-making device, they throw the extra blood into the sink and do not perform all the requested tests because they are unnecessary.

In one case, a pathologist obliged doctors who had referred patients to him by giving false results, such as labelling a healthy person a diabetic when the patient was fine. The patient would keep going to the doctor after being diagnosed, generating extra fees.

In another, a pathologist lamented that, of the 150 doctors he contacted after setting up a new lab, only three were willing to refer patients to him for investigations without demanding a kickback.

In the past two decades, owing to the precarious state of most public hospitals, where patients sometimes share a bed and where (at least in rural areas) the X-ray machine doesn't even work, private hospitals have flourished.

Having made massive investments and faced with intense competition, many hospitals try to recoup their investment through such unethical means, including setting revenue targets for doctors to meet. Doctors who fail to hit the target are sacked.

The Sathi report came out soon after MediAngels, a Mumbai medical centre that offers second opinions, reported in January that almost 44 per cent of 12,500 patients who had been advised surgery for stents, knee replacements, cancer and infertility, were advised against it by their second consultants.

And last year, an Australian doctor, David Berger, who spent six months in India as a volunteer physician, exposed corruption in Indian medicine when he wrote an article in the saying that "kickbacks and bribes oil every part of the health care machinery".

Berger described unnecessary X-rays, MRIs, hysterectomies, routine bribe-taking and "needless deaths".

For Shukla, the report is important because it is based on the testimonies of doctors who have nothing to gain by exposing these malpractices.

"The only solution to this corruption is regulation," he says. "The so-called regulation of the Indian Medical Council is minimal or non-existent. Tell me, when has the council ever struck a doctor off?"

Given that other sectors of society - such as telecoms, petroleum and electricity - are regulated, he wants tight regulation of private medicine. "The Indian Medical Council keeps saying the problem is small, that it is confined to a few black sheep. But you need a microscope to find a white sheep," Shukla says.

A senior urologist at Apollo Hospital in New Delhi, Narasimhan Subramanian, agrees that a clear framework on testing and treatment is vital. Having seen such guidelines work in Britain, where he has practised, Subramanian says simple rules, such as those governing the treatment of patients brought into casualty with a head injury, worked well.

"The protocol tells doctors that they need not order a CAT scan unless the patient has lost consciousness, is bleeding from the ear or nose, is vomiting or a gash is visible," he says.

In a country as vast as India, change takes time to build up momentum. But a start has been made, not only with this Sathi report, but also with doctors trying to make a difference in their own field.

In June, cardiologists at India's top public hospital launched an organisation called the Society for Less Investigative Medicine (Slim).

"There is no regulation or audits on investigations to determine if they are necessary. We have the technology today to keep data and to check if a procedure was really necessary," says Slim founder Dr Balram Bhargava, who hopes other disciplines will follow in setting up their own protocols.

The Forum of Medical Ethics in Mumbai also works to improve the profession, and Shukla says he is encouraged.

"Before, there was no organised outlet for doctors to speak out," he says. "Now that we have created an outlet, we need to reach out to other groups and more doctors to create a platform for this issue."