Non-fluoridated Christchurch does not have better teeth than fluoridated Auckland

It seems every time anti-fluoride propagandists present data it is either cherry-picked, distorted or misleading. Often all three. So it is hardly a surprise to find local anti-fluoride propagandists are telling porkies again.

They have been promoting the above graphic claiming it shows people in “non-fluoridated Christchurch have “better teeth.” But the graphic is based on naive cherry-picking of the data, it ignores the effect different ethnic groups have on the data and it uses a single cherry-picked year which fits their bias.

On top of that, axis values have been chosen to exaggerate differences and the labels are incorrect. The “non-fluoridated Christchurch” category uses data for Canterbury and the “fluoridated Hamilton” category uses data of the Waikato.

It seems that several of the commenters on the Fluoride Free NZ Facebook page where this graphic was first used saw the problems and raised them. All they got is insults for their time. These organisations do not seem capable of a rational discussion.

The Ministry of Health data they use is freely available on the MoH website. It provides oral health data for 5-year-old children and year 8 children. The data is presented annually and for different regions.

So let’s have a look at what the data really says – using more normal axis ranges and separating out ethnic groups.

The top graph here is still misleading because it does not take into account the effect of different ethnic groups. However, the correct categories are used and the more rational axis really cuts the exaggerated difference down to size.

In the second graphic the data for Māori and Pacifica have been removed – the MoH describes this group as “Other” – it is mainly Pakeha. We can see that the caries-free % is actually greater for fluoridated Auckland than it is for non-fluoridated Canterbury – exactly the opposite of what the anti-fluoride propagandists were claiming.

It is the same story for Māori – the caries-free % is actually higher in fluoridated Auckland than in non-fluoridated Canterbury.

The problem with the “Total” data is that Pacifica have a large effect – particularly in Auckland where Pacifica are concentrated. Pacifica generally have poorer oral health but are concentrated in fluoridated regions. This drives down the caries-free % figures for the fluoridated areas if the differences are not accommodated.

I referred to this effect of Pacifica on the data in my article A challenge to anti-fluoridationers to justify their misrepresentation of New Zealand research. There I was referring to a similar way anti-fluoride campaigners were misrepresenting data from recent New Zealand research. In this case, they were using data from a paper (Schluter & Lee 2016) and completely ignoring the distortions introduced by inclusion of Pacific – even though the authors had warned against the anomaly introduced by this.

There are other effects which should also be considered in a proper understanding of these data. It is easy to cherry-pick the data for a single year when differences are small – the anti-fluoride people do that a lot. OK if you want to confirm your biases but consideration of the data over multiple years helps indicate trends, identify anomalies and provide an idea of variations in the data. It is also important to consider the numbers in each region. For example, I have not included Pacific in the graphs above because they are concentrated in Auckland and the numbers in Canterbury and Waikato are very low (eg., 45 in Waikato in 2014).

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Blogging for New Zealand

Picked up the press release last night. Seems to be for a good cause – the recovery of New Zealand and the Christchurch region after the tragic earthquake of February 22.

Specifically this is aimed at the tourist industry and independent travelers. The aim is saturation blogging on March 20, 21 and 22 promoting New Zealand as a travel destination. The web site describes the promotion as :

“Blog4NZ is a grassroots blogging and social media effort to support New Zealand travel in the wake of the Canterbury earthquake.

It is a worldwide blogging event happening on March 21-23, 2011 and you can be a part of it.”

If you are interested, want to contribute a blog post or publicise the event contact details are at:

Calling all travel bloggers to join Blog4NZ.

The face book page is: Blog4NZ – Blog for New Zealand on Facebook.

And you can follow on twitter using the tag # blog4nz

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The world is in shock that one of the premium travel destinations in the world could suffer such a natural disaster as happened two weeks ago in Christchurch. And while all our thoughts go out to those people who have lost loved ones, lost homes and businesses, travel bloggers around the world are uniting to tell the world New Zealand is a great place to travel and there is no better time than now.

March 21, 22, and 23 has been set aside by travel bloggers throughout the world as 72 hours of content generation about travelling to New Zealand. #Blog4NZ is the brain-child of New Zealand travel bloggers Jim McIntosh and John Reese. John himself living in Christchurch. “We want a total black-out of travel content across the world, we want Twitter dominated by Tweets about travelling to New Zealand, we hope that all travel bloggers rally behind this cause and publish as many articles as possible throughout this period about travelling to New Zealand” said event organiser Craig Martin of Indie Travel Media.

“New Zealand is one of the world’s greatest travel destinations and has been a great source for many travel bloggers and travel entrepreneurs. For many northern hemisphere countries it is the furthest most spot they can travel. It has been the place where so much innovation has come with regard to travel – the home of Bungy, the birth place of hop-on hop-off backpacker travel, NZ led the way in independent hostels throughout the eighties and nineties. It is also a country where tourism is the number one contributor to GDP, where the Minister of Tourism is the PM – that is how important tourism is. This is the travel community saying hey go to NZ – if there is one place that should be on your travel list this year it is NZ” said Dan Roberts of Travel Generation. “This is something that as the travel community we can do to support not only all the businesses in Christchurch but everyone in New Zealand.”

via Press Release: Calling All Travel Bloggers – #Blog4NZ | Blog4NZ – Bloggers Resources.

See also:
Travel Blogging Community Rallies for New Zealand
A Great Project to be Involved – blog4NZ

Wine and the Watchtower

This photo has always impressed me. A fantastic view from the International Space Station. Locals will recognise our prime wine growing areas of the Wairarapa, Blenhiem, Nelson, Waipara and Canterbury.

It also reminds me – I saw some god botherers in our street the other day. They stand out like a sore thumb, don’t they?

However, they must have got the message. They seem to have stopped knocking on my door.

Thanks to Pundit Kitchen: Would You Like A Copy Of The Watchtower?!

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What a view!

You have got to love this. Astronauts/Cosmonauts hard at work on the international space station (ISS/Zarya) while passing over some of New Zealand’s best wine regions. In the North island we can see the Wairarapa/Martinborough region. In the South Island the Marlborough, Nelson, and North Canterbury/Waipara regions.

The coming Saturday and Monday evenings should provide good opportunities for observing the International Space Station from the North Island of New Zealand – weather permitting.

See also:
Heavens Above
Real Time Satellite Tracking

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