Taxing tobacco products remains the most important factor in driving down smoking rates, researchers have reiterated after a controversial paper was released that suggested Australia’s plain packaging had done nothing to curb cigarette usage.

Medical researchers howled down the study, released by James Cook University, which compared Australian and New Zealand smoking rates between 2002 and 2017, specifically focusing on when plain packaging came into effect in Australia in 2012.

The study puts forward the premise that plain packaging had nil effect on smoking prevalence. Instead it resulted in smokers just buying cheaper brands, actually making them smoke more.

Industry analysts have called the paper everything from “flawed” to “truly terrible”.

Its fault, they say, lays in the fact they did not include tobacco tax hikes as part of their control variables.

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Although Australia had no notable hikes between April 2010 and the end of 2013, New Zealand was rolling out a 10 per cent increase in January 2011.

(New Zealand implemented plain packaging in 2018, while Australia’s annual 12.5 per cent increases didn’t begin until 2017.)

It’s an omission that fatally undermines the validity of the study, Sydney School of Public Health Emeritus Professor Simon Chapman AO said.

Professor Chapman said that while tax increases remained the “single most important variable” in reducing smoking rates, one only had to look at the reaction of the tobacco industry to see how influential plain packaging was.

“The intensity of [the tobacco industry’s] global lobbying against plain packaging was unprecedented: It fears plain packaging like no other policy,” Professor Chapman said.

Melbourne Centre for Behaviour Change deputy director Ron Borland said the study showed flaws in the process of curating the findings.

“This is truly a terrible paper. It is very high on equations and technical terms, but is based on weak data and assumptions that are manifestly inappropriate,” Professor Borland said.

Although he did concede: “The impact of smoking among a population who continue to smoke in the face of strong public education was always going to be small, and they do point out that some of the previous evaluations of plain packaging have likely overestimated effects through lack of appropriate controls (inevitable for this kind of research).”

Good results, but still some way to go

Australia’s current national smoking rate sits at 16 per cent for men and 12 per cent for women, with daily smoking at an all-time low of 11.15 per cent for Aussies aged 14 and over.

However it still costs the country some $137 billion a year, and tobacco use accounts for 10 per cent of the annual disease burden.

What hasn’t helped, experts say, is a government drop in spending on anti-smoking material.

Campaigns from the Australian, New South Wales and Victorian governments dropped from $36 million in 2010-11 to $7.1 million in 2017-18, a special report published this month says.

Tax increases and “hard-hitting” education campaigns were identified as the most effective in encouraging individuals to quit smoking.

Authors Paul Grogan (Cancer Council) and Professor Emily Banks (Australian National University’s National Centre for Epidemiology and Population Health, the Sax Institute) said that despite the known effectiveness of public campaigns, Australia’s government funding remained well below international benchmarks.

What’s needed to bring our numbers down further, they wrote, was a collaborative effort.

“Australia’s comprehensive, whole-of-government response to COVID-19 shows that our governments and other institutions can come together decisively to deal with a threat to public health,” they wrote.