The four-year long study was funded by Denmark's Danida Council for Development Research. The study, conducted by doctors from the All India Institute of Medical Sciences (AIIMS) during 2004-08 in a South Delhi slum, found that of the 207 households, only two preferred to visit the government dispensary located four kilometres from the settlement. The others felt that non-qualified medical practitioners are more humane, more communicative and offer more payment options for daily wage workers.

The study also found that non-qualified medical practitioners as well as qualified doctors prescribed similar medicines for illnesses like fever, diarrhoea, dengue, vaginal discharge and tuberculosis on first consultation. The majority of these quacks were former employees with chemists, clinics or hospitals, the researchers said.

"These quacks are the only ones who are physically present in such urban slums. Enacting laws to prohibit their practice will not make any difference, as even today, they are running their clinics without any legal protection," said C S Pandav, lead researcher and head of community medicine, AIIMS.

"Having realised the ground situation, I feel that the central government's proposed National Urban Health Mission (NUHM) should factor in their presence before framing policies. Until there is a credible alternative, they will continue to play a role in the healthcare delivery network in slum areas," he added.

The researchers also quoted Delhi Medical Council estimates to suggest that about 40,000 such non-qualified medical practitioners are functioning as the primary healthcare contact.

According to them, police raids to close down such clinics often prove unsuccessful due to the local support enjoyed by such practitioners.

Besides Delhi, studies were also conducted in Bhubhaneswar to understand the healthcare patterns of the urban poor. Bhubhaneswar however presented a different picture, with a very low presence of non-qualified medical practitioners. Most of the rural households in the area said that their first point of contact is the local chemist and not the doctor.

Reacting to the study, Suyash Prakash, mission director, Delhi State Health Mission said that two-thirds of Delhi's population of over 11 million live in the slums. "If 80 per cent of these 11 million are being attended to by non-qualified medical practitioners, it is a serious matter," he said.

He added that there are no credible figures for the number of quacks in Delhi and put the number at 5,000.