Authorities will investigate a doctor over concerns he was not fully qualified for his job and examine why it took a month for knowledge of a past criminal charge to reach the top.

Queensland Health stood down Zimbabwe-trained Dr John Chibanda over concerns he was working outside the scope of his credentials at Emerald Hospital.

The matter will be investigated by both the Health Quality and Complaints Commission and the state’s Crime and Misconduct Commission.

Dr Chibanda, an Australian citizen, had previously worked at Katherine Hospital in the Northern Territory without incident.

He started work in obstetrics at Emerald Hospital in late 2007 and was supervised due to the level of his experience.

After complaints about the standard of his work around August 2008, he was stood down from obstetrics, but continued to work in emergency and other general areas of the hospital.

He was again investigated after further complaints in May this year, and a Google search in late September turned up a criminal charge for fraud in Zimbabwe.

Health Minister Paul Lucas said Dr Chibanda was challenged about the information – which related to the fraudulent supply of a death certificate for insurance purposes – and he claimed the conviction had been quashed.

"However, the form that one is required (to fill in) when one seeks registration as a doctor in Queensland clearly requires … that one disclose not just criminal convictions but if one has ever been charged with a criminal offence," Mr Lucas said.

"I want to make it crystal clear.

"I expect there to be a full and rigorous investigation of these matters.

"If there is anyone who has misled, if the wrong thing has been done, then there will be no forgiveness, no mercy, there will be very, very strong action."

About a dozen complaints were made about Dr Chibanda – some from patients and some from nurses – but none relate to deaths or permanent injuries.

Also under investigation is why it took about a month for his criminal history to be reported to the top, with Queensland Health’s centre for healthcare improvement chief Dr Tony O’Connell saying he only became aware of the matter this week.

Mr Lucas said the appropriate checks through medical bodies and referrals were done, in addition to an earlier Google search that had failed to pick up the fraud matter.

"I would have thought that we would be bending over backwards to check these things," Mr Lucas said.

"I would have thought that the relatively modest things that you can do in addition to the rigorous checks would be second nature, and I want it investigated as to why this happened."

Dr O’Connell said "a few dozen" obstetrics cases handled by Dr Chibanda and hundreds of other cases would be reviewed.

Patients with concerns about treatment by the doctor were urged to come forward.

Dr Chibanda is the second doctor to be stood down from Emerald Hospital within months. A doctor at the hospital was suspended in September over a disciplinary matter.

In September, staff in Central Queensland discovered Dr John Chibanda had been convicted of falsifying a death certificate in Zimbabwe.

Dr Tony O’Connell from Queensland Health says staff did not pass the information on until this week.

"That’s an aspect which the Deputy Premier wants investigated by the Health Quality and Complaints Commission – are there systemic issues here," he said.

Health Minister Paul Lucas says patient files are being reviewed but no deaths have occurred.

Mr Lucas says an earlier internet search did not reveal the conviction.

"The medical board put in ‘John Chibanda – discipline’ and it didn’t show up under that basis, but if one puts in ‘John Chibanda’ without putting anything else in it does," he said.

Dr Chibanda has declined to comment, but has told health authorities the conviction was quashed.

The Northern Territory Department of Health says Dr Chibanda worked as a medical officer at Katherine District Hospital for almost two years until he resigned in October 2007.

It says his conditions of employment included working under the supervision of senior medical staff.

The Department says during the time Dr Chibanda worked in the Territory no complaints about his work were made to the Northern Territory Medical Board.