Australia and New Zealand remain among a small group of countries that have so far managed to subdue the deadly coronavirus pandemic.

But Prime Minister Scott Morrison has been keen to stress Australia is not entirely in lock-step with its trans-Tasman neighbour.

In an April 16 media conference, he said New Zealand had imposed a "state of even more extreme lockdown" than Australia, but had been less successful at suppressing the virus after accounting for population size.

"New Zealand decided to go a lot further, but I'd note that the outcomes we are getting are actually on a per capita basis actually better than what is happening in New Zealand," Mr Morrison said.

Is it correct that Australia achieved better per capita outcomes, even though New Zealand "decided to go a lot further" with its economic and social lockdown? 

His suggestion that Australia achieved "better" outcomes on a per capita basis than New Zealand can be approached from several angles, including total confirmed cases per capita, new daily cases per capita, the total number of deaths per capita, or the number of daily deaths per capita.

Australia has not achieved a better outcome than New Zealand in terms of total (cumulative) cases per capita.

Nor has Australia achieved a better result on the number of total confirmed deaths per capita. 

However, following both countries' respective lockdowns, Australia was recording lower numbers of new daily cases per capita, using a three-day rolling average to iron out volatility.

Australia was also recording fewer daily deaths per capita, again using a three-day rolling average.

These measures capture the picture after the lockdowns were imposed, and better reflect Mr Morrison's claim about  "the outcomes we are getting".

However, any differences between the two countries have been marginal.

Moreover, the circumstances facing Australia and New Zealand were not identical.

During the week in which both countries ramped up their respective lockdowns (March 23 to March 29), New Zealand experienced a very rapid acceleration in spread of the virus, with the number of cases per capita jumping 371 per cent, compared to a 122 per cent increase in Australia.  

New Zealand was also testing at a higher rate, raising the possibility that more cases were being identified, and potentially giving the false impression that eradication efforts were more successful in Australia.

As experts noted, it is too early to make definitive judgements. 

The verdict: Mr Morrison's claim is a fair call.