The psychiatrist in charge of the '1000 Letters' suicide project has acknowledged it could do harm.

The study calls for people to submit notes or letters left by suicide victims, in the name of research. It aims to analyse suicide notes for themes and is being carried out by the Key to the Life Charity, fronted by comedian, New Zealander of the Year and mental health activist Mike King.

Despite serious concerns the research could be putting lives in danger, the charity has not suspended it.

On Tuesday, Mr King told Checkpoint he would not obey the Health Ministry's call to cease and desist.

The study does not have ethical approval and following complaints, the Ministry of Health has asked for it to be halted immediately, until it meets all requirements.

Psychiatrist Dr Siale Foliaki is the chair of the Key to Life Charitable Trust. He told Checkpoint's Lisa Owen he accepts there is "real risk" to what they are doing but argues there may be benefits too.

"I think you should always be concerned about the potential of any activity within our community to trigger people that are close to the activity itself," he said.

But if something useful could be learned on balance, he said he believed the potential good was greater than the potential harm.

"At this stage, we still haven't made a full commitment to whether we turn this into a study of the type that you can publish in an academic sense.

"I think it potentially still can be a study, but I think there's potentially a way to move forward that doesn't necessarily represent what our earlier public releases had stated."

However, Dr Foliaki said he was not backing away from the 1000 letters study.

The study had not yet gone before an ethics committee, he said, and did not have a lead researcher, but did have a study protocol. He said they would establish a peer review protocol if they moved forward with the study, which the charity was currently gathering the suicide letters for.

The Ministry of Health requires ethical approval prior to research, and approval cannot be given retrospectively.

Dr Foliaki said Key to Life's project has not followed the Ministry of Health's process, but that does not mean it was necessarily unethical.

He does accept that the process could be unsafe, considering the triggering possibility for people who have been affected by a suicide.

"There's not a strong body of evidence that says the process of asking for people to send us information of a very sensitive nature… is a dangerous thing to do. There isn't that body of evidence.

"But as an individual clinician, and as a person that cares about this particular issue, I'm prepared to accept that yes, this process may not necessarily have been as well thought-out as it could have been or should have been. I'm prepared to accept that."

Dr Foliaki said the decision was about weighing up potential risk to potential benefit, "and at this moment in time, I think there's potential benefit in this, and we just need to consider what steps we take to get that benefit and mitigate, manage the risk."

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