Anti-fluoridationist Paul Connett misrepresents NZ data

Slide 110 from Paul Connett’s presentation prepared for his planned meeting at Parliament Buildings last February

Here is another post in my series critiquing a PowerPoint presentation of Paul Connett – a leading US anti-fluoridation activist.

Paul prepared this for a meeting in New Zealand Parliament buildings last February. Although only three MPs turned up his presentation is important as it summarises almost all the arguments used by anti-fluoridation activists.

Connett claims NZ data shows fluoridation ineffective

Connett argues the evidence community water fluoridation (CWF) is effective in reducing tooth decay is weak. He covers this in slides 96-110 but in this post I will deal only with the New Zealand evidence he uses (slides 108-110).  Paul’s presentation can be downloaded for those wishing to look at it in detail – see Prof Paul Connett Power Point Presentation to Parliament 22nd Feb 2018.

The total New Zealand evidence Connett presents for this is a graphic obtained from his NZ offsiders, Fluoride Free NZ (FFNZ):

We know how unreliable FFNZ is as a source and the data is obviously cherry-picked. But what is the truth? What do the NZ School Dental statistics really say about the oral health of children in NZ?

I have covered this before – FFNZ misrepresentation of the MoH data is an annual event occurring each time the Ministry of Health adds its annual summary of the data to their web pages.

For a change, here is a breakdown and discussion of the 2016 data prepared by Environmental Health Indicators NZ in association with Massey University:

“Children in fluoridated areas generally have better oral health”

“Children living in communities with fluoridated drinking-water generally had better oral health than children living in non-fluoridated communities.

In 2016, around 60 percent of 5-year-olds were caries-free in their primary teeth. Rates were similar in fluoridated communities (60 percent) and non-fluoridated communities (60 percent) (Figure 1).

More Māori and Pacific Island 5-year-olds were caries-free in fluoridated communities than in non-fluoridated communities in 2016. The largest difference can be seen for Māori children.

5-year-olds had on average 1.8 decayed, missing or filled primary teeth in 2016. Children living in fluoridated communities had less decayed, missing or filled teeth than children living in non-fluoridated communities (Figure 2).

This difference is particular large for Māori children. 5-year old Māori children had on average 2.5 decayed, missing or filled teeth in fluoridated communities compared to 3.3 decayed, missing or filled teeth in non-fluoridated communities in 2016.”

I am unable to embed the Environmental Health Indicators NZ graphs, but they are essentially the same I presented in my article Anti-fluoridationists misrepresent New Zealand dental data – an annual event so I reproduce that section of the article below:

---

What does the new data really say?

Let’s look at a summary of the data – for 5-year-olds and year 8 children – and for the different ethnic groups listed – Māori, Pacific Island and “other”(mainly Pakeha and Asian).  You can download the spreadsheets contain the data from the MoH web page – Age 5 and Year 8 oral health data from the Community Oral Health Service. We will look at the % of these children that a free from caries as well as the mean decayed, missing and filled teeth (dmft and DMFT) for each group.

5-year-olds

Notice the FFNZ cherry picking? Yes, the “Total” figures show very little difference but if they had dared look at different ethnic groups their argument would not have looked so great. Fluoridation appears to be associated with an improvement of dental health from about 6% (for “Other”) to 23% (for Māori)

Year 8 children

You can see why  FFNZ chose the 5-year-olds instead of year 8 children. Even the misleading data for the “Total” group suggests an almost 20% improvement of dental health in fluoridated areas.  Fluoridation appears to be associated with an improvement of dental health from about 18% (for “Other”) to 30% (for Māori).

---

What’s the problem with the 2009 Oral Health Survey?

Anti-fluoride activists love to hate this survey because it concluded:

“Overall, children and adults living in fluoridated areas had significantly lower lifetime experience of dental decay (ie, lower dmft/DMFT) than those in non-fluoridated areas. There was a very low overall prevalence of moderate fluorosis (about 2%; no severe fluorosis was found), and no significant difference in the prevalence of moderate fluorosis (or any of the milder.

“These findings support international evidence that water fluoridation has oral health benefits for both adults and children. In addition, these findings should provide reassurance that moderate fluorosis is very rare in New Zealand, and that the prevalence of any level of fluorosis was not significantly different for people living in fluoridated and non-fluoridated areas.”

Yes, it covers only the period up to 2008 and it would be good to get more recent high-quality data from a similar study.

But Connett’s accusation of “cherry-picked data” is simply wrong – and dishonest. In fact, scientific principles were used to obtain a representative sample for the survey – recognising that oral health is strongly influenced by ethnic, regional and fluoridation differences.

The methods used are explained in 22 pages of the report –  MoH. (2010). Our Oral Health Key findings of the 2009 New Zealand Oral Health Survey. 

In contrast, the annual School Dental Data is simply a record of overall findings. There is no attempt to standardise diagnostic and reporting methods to the standard of the Oral Health Survey or scientific studies.

But, of course, it provides a lot of data which can be cherry-picked to support a specific argument or confirm a bias. FFNSZ and Paul Connett have ignored all the known ethnic, social and regional differences in their cherry-picking. Consequently, their reported “findings” do not have credibility.

Conclusion

I think it is somewhat disrespectful of Paul Connett to include such a shonky bit of misrepresentation in a presentation prepared for members of parliament. It is also disrespectful in that he relies on his scientific qualifications, his Ph. D. to give “respectability” to a scientific argument which is so easily shown to be false.

Surely our members of parliament deserve something better than this.

Although, even with members of parliament, I guess the old adage “reader (or listener) beware” applies. Sensible MPs will not accept such assurances at face value and will seek out adive=ce on such matters from their officials and experts.

I guess we should feel pretty confident that most of our MPs are sensible in this repect. The fact they did not turn up to a meeting to hear someone well-known for misrepresenting the science is telling – and this despite the fact that anti-fluoride activists were exerting strong pressure on MPs to attend.

Politicians have experienced, and learned from, excessive lobbying, pressuring and untruthful submissions precisely because of their targeting by anti-science activist groups like FFNZ. They know this is why local councils wanted the central government to take over fluoridation decisions.

I suspect our parliamentary politicians are a little more mature than our local body politicians and now  treat such organised campaigns like water off a duck’s back.

Similar articles

 

Anti-fluoridationists misrepresent New Zealand dental data – an annual event

Caught again! – NZ anti-fluoride campaigners tell their annual porky about the MoH statistics for the dental health of school children.

This exercise in confirmation bias by New Zealand anti-fluoridation campaigners has become an annual tradition involving confirmation bias and cherry-picking. Every year the Ministry of Health (MoH) releases a spreadsheet containing the most recent data on school children’s dental health. And every year the Fluoride Free NZ (FFNZ) activists select some figures from the spreadsheet to argue their case that fluoridation is not effective. A simple exercise in bias confirmation by cherry picking.

I wrote about last year’s exercise in my article Anti-fluoridationists misrepresent new dental data for New Zealand children. That involved the MoH data for 2015. My comments on their misrepresentation of the newly released 2016 data will be much the same.

FFNZ claims the 2016 statistics:

“show absolutely NO difference in dental decay rates between five year olds in fluoridated areas compared to non-fluoridated areas.”

Notice the specifics – 5-year-olds. And no mention of ethnicity. They have simply used the total figures (which mislead because of effects of ethnic differences) and cherry-picked the specific data where the figure for fluoridated areas and non-fluoridated areas are very close.

What does the new data really say?

Let’s look at a summary of the data – for 5-year-olds and year 8 children – and for the different ethnic groups listed – Māori, Pacific Island and “other”(mainly Pakeha and Asian).  You can download the spreadsheets contain the data from the MoH web page – Age 5 and Year 8 oral health data from the Community Oral Health Service. We will look at the % of these children that a free from caries as well as the mean decayed, missing and filled teeth (dmft and DMFT) for each group.

5-year-olds

Notice the FFNZ cherry picking? Yes, the “Total” figures show very little difference but if they had dared look at different ethnic groups their argument would not have looked so great. Fluoridation appears to be associated with an improvement of dental health from about 6% (for “Other”) to 23% (for Māori)

Year 8 children

You can see why  FFNZ chose the 5-year-olds instead of year 8 children. Even the misleading data for the “Total” group suggests an almost 20% improvement of dental health in fluoridated areas.  Fluoridation appears to be associated with an improvement of dental health from about 18% (for “Other”) to 30% (for Māori)

Importance of ethnic classifications.

The figures above show big differences between ethnic groups, with the dental health of Pacific Island children being the worst.

This is an important factor because most Pacific Island children live in fluoridated areas – about 85%. The figure below shows the distribution of the two different age groups.

This means that the overall, or “Total” data is distorted. Pacific Island children predominance in fluoridated areas increase the value of dmft/DMFT and lowers the value of caries-free % in the fluoridated areas.

So the FFNZ activists are not only cherry picking to confirm a bias – they have selected the figures which are most distorted by ethnic differences.

Far from the latest data showing “absolutely NO difference” it actually shows differences of the order of 18 -30%.

Similar articles

Anti-fluoridationists commonly misrepresent Ministry of Health data

Anti-fluoride activists tell porkies about the Ministry of Health’s data on child dental health. They cherry-pick the data to make it appear that community water fluoridation is ineffective. And when challenged to discuss the issue they run away.

---

I am currently dealing with family issues so am reposting this article, “A challenge to anti-fluoridationers to justify their misrepresentation of New Zealand research”  from April 2016.  It shows how local anti-fluoride activists are misrepresenting the Ministry of Health’s data on child oral health

---

One of the frustrations I have with the fluoridation issue is the refusal of anti-fluoride activists to engage on the science. They will pontificate, but they won’t engage in discussion.

On the surface, one would think there is a difference of opinion or interpretation of scientific issues and that could be resolved by discussion. Yet local anti-fluoride campaigners refuse to enter into discussion. Again and again, I have offered space here to local anti-fluoride campaigners so that they could respond to my articles and they have inevitably rejected the offer. They have also blocked me, and other people discussing the science, from commenting on any of their social media pages or web sites. Even when they, themselves, call for a debate they reject specific responses I have made accepting that call.

So I am left with the only alternative of responding to their claim with an article here – or on a friendly web or blog site. At least that gives me space to present my argument – I just wish I could get some intelligent responses enabling engagement on the issues.

Misrepresentations repeated

The latest misrepresentation of the science is a claim by the Auckland Fluoride Free NZ Coordinator, Kane Titchener, that “recent research proves fluoridation [is] not needed.“

It repeats the same misrepresentation made by Wellington Anti-fluoride campaigner, Stan Litras, which I discussed in my article Anti-fluoridation cherry-pickers at it again. Kane has either ignored my article, chosen to ignore it or possibly not even understood it.

So here we go again.

Kane claims:

“A New Zealand study published in Bio Medical Central Oral Health last month shows dental health improved the greatest extent for children in non-fluoridated areas. There is now no difference in dental decay rates between non-Maori children who live in fluoridated areas and non-Maori children who live in non-fluoridated areas, proving that fluoridation is not needed for children to obtain good dental health.”

Although he doesn’t cite the study (wonder why), his use of two figures from the study show he is writing about the paper:

Schluter, P. J., & Lee, M. (2016). Water fluoridation and ethnic inequities in dental caries profiles of New Zealand children aged 5 and 12–13 years: analysis of national cross-sectional registry databases for the decade 2004–2013. BMC Oral Health, 16(1), 21.

His claim relies on the comparison of data for “non-Māori” children in fluoridated and fluoridated areas. No – he doesn’t misrepresent the data – he just ignores the discussion by these authors of problems with simple interpretation of the data for non-Māori because of the fact it is not ethnically uniform. In particular, he ignores the qualifications they place on the data because of the inclusion in non-Māori of data for Pacifica who have poorer dental health than the rest of this group and live predominantly in fluoridated areas. This, in effect, distorts the data by overestimating the poor oral health for “non-Māori” in the fluoridated areas.

The apparent convergence

The data used in this study were taken from the Ministry of Health’s website. This divides the total population of children surveyed into the ethnic groups Māori, Pacific and “Other.” While the “other’ group will not be completely uniform (for example including Pakeha, Asian, other groups) it becomes far less uniform when combined with the Pacific group to form the non-Māori group.

So, Kane salivates over this figure from the paper especially the plots for  non-Māori ethnicities in fluoridated (F) and non-fluoridated (NF) areas.

Fig. 1 No obvious decay experience (caries-free) percentages and mean dmft for 5-year old children over years 2004 to 2013, partitioned by Māori and non-Māori ethnicities and fluoridated (F) and non-fluoridated (NF) areas

Yes, that convergence is clear and I can see why Kane is clinging to it – who can blame him. But he completely ignores the warning from the paper:

“It is likely that a substantial driver of this convergence was due to significant changes within the dynamic and heterogeneous non-Māori groups both within and between DHB regions. In effect, the ecological fallacy – a logical flaw whereby analyses of group data are used to draw conclusions about an individual – may be operating within the non-Māori group.”

When the Pacific data is removed (as is the case for the “other” group effectively made up from non-Māori and non-Pacifica) we get the plots below.

Comparison of data for “other” (non-Māori/non-Pacifica) children in fluoridated (F) and unfluoridated (UF) areas.

Nowhere near as useful for Kane’s confirmation bias and the message he wants to promote. OK – there is still some evidence of convergence from about 2007 on between fluoridated and unfluoridated children. But the graphs do show that community water fluoridation is still having  a beneficial effect. And this apparent convergence could be explained by things like the introduction of “hub and spoke” dental clinics after 2004. One problem with this raw data is that children are allocated according to the fluoridation status of the school – rather than their residence. This will lead to incorrect allocation in some cases.

Some data for Pacifica

Just to underline the problems introduced by inclusion of Pacific in the non-Māori group of the study consider the data for Pacifica shown below.

Data for 5-year-old children. dmft = decayed, missing and filled teeth. The “other” group is non-Māori and non-Pacifica

The oral health of Pacifica is clearly poorer than that of the “other” group.

Also, Pacifica make up about 20% of the non-Māori fluoridated group. So they will influence the data for the non-Māori fluoridated group by reducing the % caries free and increasing the mean dmft.

So Kane, like Stan, is blatantly cherry-picking. He is misrepresenting the study – and its author – by ignoring (or covering up) the qualifications regarding the influence of inclusion of pacific in the non-Māori fluoridated group.

The challenge

Now, I repeat the offer I have made in the past to give a right of reply to both Kane Titchener and Stan Litras. They are welcome to comment here and if they want more space I am happy to give space for separate articles for them in the way I did for the debate with Paul Connett. Now I can’t be fairer than that, can I?

So what about it Stan and Kane? What are your responses to my criticisms of the way you have cherry-picked and misrepresented this New Zealand paper?

---

NOTE: I have sent emails to both Kane and Stan asking them to respond and offering them right of reply.

UPDATE 1: Great minds and all that – Stan Litras sent out a press release today calling for a nation-wide debate on this issue (see FIND calls for a national debate on fluoridation). However, the seriousness of his request is rather compromised by his reply to my offer of a right of reply to the above article. He did respond to my email very quickly. This is what he wrote:

“Thanks for the offer, Ken, but I have not visited your blog site for a long time, as I object to the way you attempt to defame and discredit me.

You play the man and not the ball, which is not the mark of a reasonable person.

I hope to address that in due course as time permits, but for now I must leave you to indulge yourself without my company.”

So much for his wish for a “national debate” when he will not front up to a critique of his claims about the science.

UPDATE 2: Kane Titchener today also posted a press release today which was the text of the article I discuss in this post (see NZ research proves fluoridation not needed). He also responded quickly to my e-mail. The full text of his response was:

“Who is this?”

Rather strange – considering he often pesters me with emails.

So I guess both of them have turned down my offer.

Similar articles

“Do the math” – a bit like “Do the research!”

Cherry-picking data is an old technique used by those who wish to raise doubt about a scientific consensus. On the one hand, it isolates the cherry-picked data from their context and the rest of the data. On the other hand is present a “sciency” authority to the argument by pretending to be evidence-based.

I have written about cherry-picking in several articles discussing the fluoridation issue – so nothing new here. But the current surge of activity by anti-fluoridation activists  attempting to raise doubt with the upcoming parliamentary discussion of new legislation on fluoridation is producing a fresh wave of cherry-picked arguments.

The image here is just one example in a letter to the Christchurch Press a few days ago. I thought it worthwhile to actually check out the quoted figures to see if the arguments awere justified.

Firstly, the figures were taken from the Ministry of Health’s 2014 data for the dental health of New Zealand children. Unfortunately, while the actual numbers used are correct, the data has since been withdrawn because of errors in the spreadsheet. So I will use the data for earlier years,  2005 – 20013, in my analysis.

The overall picture

First off – the overall picture shown by the Ministry of Health data is that community water fluoridation does reduce tooth decay. Of course, that is why the anti-fluoride campaigner rarely discusses the overall picture – instead, they cherry-pick data to confirm their bias. The figure below is for 5-year-olds  averaged over the years 2005-2013

I have separated the data by ethnicity because of the big differences Māori and Pacifica on the one hand and the other ethnic groups on the other. In particular, the dental health of Māori and Pacifica children is poorer. This is an important factor which needs to be taken into account when comparing data from different regions. I discussed this further in my article Anti-fluoridation cherry-pickers at it again.

Data for Canterbury

It is likely that at least some of the 2014 spreadsheet mistakes were in the Canterbury data – but still the claim that there is no real difference between data for fluoridated and non-fluoridated areas could well be true – at least for some years. The figure below displays the data for 5-year-old children. Choose your year and you will get the answer you want to confirm your bias. Children from fluoridated areas seem to have poorer teeth in 2008 and 2010 and better teeth in 2012 and 2013.

MoH 5-year-old child dental health data for 2005-2013. dmft = decayed, missing and filled teeth.

The plots in the above figure indicate how unreliable such comparisons are for Canterbury because the fluoridated data is all over the place. This is because of the very low number of children in the fluoridated area: 22 – 70 over the years, 42 on average. There were on average 4720 children in the non-fluoridated areas. Children from the fluoridated area usually comprised less than 1% of the total.

The data for Canterbury does not deny the effectiveness of fluoridation, as the letter writer claims. They just show that no conclusion can be drawn from this cherry-picked data. At least I cherry-picked the data from 2005-2013 which enabled me to see how unreliable they were. The letter writer just cherry-picked one year! What will they do if the corrected spreadsheet for 2014 no longer supports their bias – switch to 2010 instead?

Comparing Canterbury and Waikato data

Here we have a different problem. The letter writer has simply cherry-picked these figures because they confirm her bias. She has not taken into account the important influence that ethnic composition has. Any intelligent analysis of this comparison must consider this aspect.

This is the ethnic composition of the 5-year-olds MoH data (averaged over 2005-2013).

	Canterbury	Waikato
Māori (%)	10.2	31.5
Pacifica (%)	3.2	2.1
Other (%)	86.6	66.4

So, whereas only 13.4% of Canterbury 5-year-olds are Māori or Pacifica, 33.6% of Waikato 5-year-olds are Māori or Pacifica. This is an important difference – especially as the dental health of Māori and Pacifica is poorer than others as demonstrated in the first figure .

Any analysis that does not take this difference into account will be misleading.

As well as ethnic distribution between regions there is also the influence of ethnic distribution between the fluoridated and non-fluoridated areas. This was a factor I discussed in Anti-fluoridation cherry-pickers at it again. The graphic below for 5-year-old children shows Māori and Pacifica are more concentrated in the fluoridated Waikato areas than in the non-fluoridated ones.

Distribution of Māori and Pacifica between fluoridated and non-fluoridated areas.

We can ignore the bar for fluoridated Canterbury because of the very small numbers.

What this means is that the mean value for fluoridated Waikato areas is decreased by the higher presence of Māori and Pacifica than in the non-fluoridated Waikato areas. This higher proportion Māori and Pacific in the Waikato region also affects the comparison of the two regions made by the letter writer.

Rather than comparing oranges with apples, let’s compare Canterbury and Waikato for the same ethnic group – Others (not including Māori and Pacifica). As the figure below shows, removal of the effect of Māori and Pacifica from the Canterbury data increase the caries-free percentage – but it is still slightly less than the equivalent data for the fluoridated Waikato areas.

So much for children from non-fluoridated Canterbury areas having better teeth than children from fluoridated Waikato areas.

Auckland and Counties/Manakau

Some anti-fluoride campaigners are pulling the same trick – asserting the dental health of non-fluoridated Canterbury children is better than for the fluoridated Auckland and Counties/Manakau children.

Here is a comparison of the ethnic composition of the three regions for the 2013 5-year-old MoH data.

	% Māori + Pacifica
Canterbury	13
Auckland	32
Counties/Manakau	52

See the problem? It is just completely naive – or worse, dishonest – to compare data between regions like this without taking ethnic composition into account.

But that is not going to stop the determined activist who will just cherry-pick whatever fits their bias. I think the naive presentation of data in this way is no more justified by the declaration “Do the math” than misrepresentation of the science is justified by the declaration “Do the research!”

Note: I am well aware that the MoH data have other problems. A truly scientific analysis would also take into account factors like the degree of misallocation of children due to different fluoridation status of home and school, dental treatments such as fluoride varnishes differently used in different regions, missing data, different proportion of attendance according to region and ethnicity, etc. I am not the person to make such a thorough analysis. My sole purpose here is to show how such raw data can be misused for confirmation bias and “sciency” support of mistaken political agendas.

Similar articles

Anti-fluoridationists misrepresent new dental data for New Zealand children

Another whopper from the anti-fluoridation movement in New Zealand.

They claimed yesterday that “data released by the Ministry of Health today confirm that water fluoridation is having no noticeable effect in reducing tooth decay” (see DHB Data Show No Benefit From Water Fluoridation).

Yet a simple scan of the data (which can be downloaded from the MoH website) shows this to be patently untrue.

Here is a graphical summary of the New Zealand-wide data for 5-year-olds and year 8 children. It is for 2014 and I have separated the data ethnically as well as presenting the summary for all children (“total”).

DMFT and dmft = decayed, missing and filled teeth.

Now – don’t these figures show the press release headline and the first sentence  are completely dishonest?

The data for all children (“total”) Maori and “other” show children in fluoridated areas have a higher percentage of caries-free teeth and a lower mean value of decayed, missing and filled teeth. The data for Pacifica are less definite – because the vast majority of Pacific children live in fluoridated areas. I discussed this further in my last post A challenge to anti-fluoridationers to justify their misrepresentation of New Zealand research.

Cherry-picking

So the headline and main message of the anti-fluoridationists press release were outright lies. However, they will fall back on the claim that the press release does contain some facts.  But these are just cherry-picked snippets taken out of context to confirm the bias of the anti-fluoride mind.

For example, comparing data for Christchurch and Nelson-Marlborough with those for  Auckland and Counties-Manukau is just disingenuous if the ethnic differences (which we know clearly play a role in oral health) are not considered. Similarly, reference to the 2o14 “overturning” of the Hamilton Council decision to stop fluoridation is just silly considering that there are no separate data for the city and the Hamilton Council fiasco over water fluoridation overlapped the period the data covers.

Of course, this press release has been processed through the international anti-fluoridation – “natural”/alternative health media channels so expect to be bombarded with international reports based on these lies.

The lesson from this little story – don’t take claims made by anti-fluoridation campaigners, or similar activists with an anti-science agenda, at face value. Always check them out.

Similar articles

Anti-fluoridation cherry-pickers at it again

Anti-fluoride campaigners seem to be a sixes and sevens on whether community water fluoridation (CWF) is effective or not. Some will accept CWF is effective in improving oral health but moan about the ethics or reports of harm. Others will simply claim CWF is not effective.

Stan Litras is a Wellington dentist and anti-fluoride campaigner in the later camp. He continually denies that CWF is effective and claims he has science to back up his claim. However, what he actually means is that of he cherry-picks the science, holds his mouth the right way and prevents you from looking at the context and data – he can find a quote to support his position.

I have debunked his claims before in my articles – such as, Cherry-picking and misinformation in Stan Litras’s anti-fluoride article and Cherry-picking and misinformation in Stan Litras’s anti-fluoride article. But he is at it again. This time he is misrepresenting a recent New Zealand research paper in a recent letter to the Christchurch Press.

There are several misrepresentations in his letter but here I will just take issue with the highlighted text. Stan claims:

“The DHB’s Dr Martin Lee published a research paper recently which showed little or no benefit from water fluoridation, a finding consistent with the modern weight of evidence.”

It is always best to check out such claims and I have hunted down the paper Stan probably refers to. It is:

Schluter, P. J., & Lee, M. (2016). Water fluoridation and ethnic inequities in dental caries profiles of New Zealand children aged 5 and 12–13 years: analysis of national cross-sectional registry databases for the decade 2004–2013. BMC Oral Health, 16(1), 21.

This is linked to the full-text version so readers can check out the paper itself.

Far from showing “little or no benefit” from water fluoridation the abstract actually says:

“Significant and sustained differences were observed between Māori and non-Māori children, and between CWF and non-CWF exposed groups.”

Stan ignored that sentence but latches on to (or cherry-picks) the next sentence:

“However, a convergence of dental profiles between non-Māori children in CWF and non-CWF regions was observed.”

But he ignores completely the authors’ discussion of this apparent convergence. Obviously, the discussion doesn’t support Stan’s anti-fluoride bias! But that discussion is interesting and worth considering.

Is there a convergence?

I have noted this convergence before in my articles Cherry picking fluoridation data and Fluoride debate: Response to Paul’s 5th article where I used similar data to that used in Schluter & Lee (2016). That data is available on the Ministry of Health’s website.

The graphs below show the raw data for all (“total”) children and for Māori:

% CARIES FREE

MEAN DECAYED, MISSING AND FILLED TEETH

So, yes, there is a convergence in the sense that the differences in the oral health of children in fluoridated and unfluoridated areas appears to be reducing with time. I have speculated that the apparent convergence could have something to do with the introduction of “hub and spoke” dental clinics after 2004. One problem with this raw data is that children are allocated according to the fluoridation status of thew school – rather than their residence. This will lead to incorrect allocation in some cases.

However, this paper suggests another reason for the convergence which I hadn’t considered.

Changes in and composition of the non-Māori group

The authors say:

“Another notable feature was the apparent convergence of prevalence estimates amongst non-Māori children in CWF and non-CWF areas. It is likely that a substantial driver of this convergence was due to significant changes within the dynamic and heterogeneous non-Māori groups both within and between DHB regions. In effect, the ecological fallacy – a logical flaw whereby analyses of group data are used to draw conclusions about an individual – may be operating within the non-Māori group.”

This is interesting and is supported by the data.

First, let’s note that while I compared data for Māori children with the total data in my figures above these authors have actually compared data for Māori and non-Māori. This shows a clearer convergence for non-Māori children than for all children – see this figure for 5-year-old children from the paper (dmft = decayed, missing and filled teeth per child):

Fig. 1 No obvious decay experience (caries-free) percentages and mean dmft for 5-year old children over years 2004 to 2013, partitioned by Māori and non-Māori ethnicities and fluoridated (F) and non-fluoridated (NF) areas

The picture is similar for year 8 children.

So you can see why anti-fluoride campaigners would love to cherry pick the non-Māori data. I predict that Stan and other anti-fluoridation campaigners will be reproducing parts of this figure in their propaganda for future use.  That graph is just too good for them not to cherry-pick.

But we need to remember that the non-Māori group is not ethnically uniform. In particular, Pacifica make a large contribution to this group. That contribution is unevenly distributed between the fluoridated and fluoridated groups. And it has changed over time.

• In 2013 about 86% of Pacific live in fluoridated areas – over the period covered by these MoH records this proportion has varied between 80 and 90%.
• In 2013 Pacifica make up about 12% of the non-Māori group (between 2007 and 2o13 this has varied between 9.0 and 12.7%)
• In 2013 Pacific make up about 19.3% of the non-Māori fluoridated group (between 2007 and 2013 this has varied between 14.9 and 20.7% of the non-Māori fluoridated group).

MoH data confirms problem of Pacific inclusion

So the oral health of Pacifica can have a relatively large influence on the data for the non-Māori group – particularly for the fluoridated non-Māori group where they are included. This becomes important when we realise that the oral health of Pacifica is markedly poorer than for the rest of the non-Māori group. I have illustrated this using the average of data for fluoridated 5-year-olds in the period 2007 – 2013.

Data for 5-year-old children. dmft = decayed, missing and filled teeth. The “other” group is non-Māori and non-Pacifica

So the poorer oral health of Pacifica will drag down the % caries free and drag up the mean dmft data for the fluoridated non-Māori group. However, this will have little influence on the unfluoridated non-Māori group because of the very small Pacific contribution.

We can confirm this with the raw data from the Ministry of Health website. That data is given separately for Māori, Pacifica and “other” (non-Māori/non-Pacific). The figure below shows this data for the 5-year-old children.

Comparison of data for “other” (non-Māori/non-Pacifica) children in fluoridated (F) and unfluoridated (UF) areas.

OK – there is still some evidence of convergence from about 2007 on between fluoridated and unfluoridated children. But the graphs do indicate that CWF is still having  a beneficial effect.

But I think Stan and his mates will prefer to cherry-pick the data for the non-Māori group and keep very quiet about the distorting effect that inclusion of Pacific in this group has had on the apparent convergence.

Note: I have used the raw Ministry of health data in this discussion. Schluter & Lee (2016) used standardised estimates to account for the difference in the numbers of unexamined children according to ethnicity.

Similar articles

Are submissions on fluoridation worth it?

Like most people I struggle to find the energy when representative and government bodies call for submissions. But I did make the effort recently when Medsafe called for submissions on their proposed clarification of how fluoridating agents are defined in the medicine regulations. I am pleased to see the simple suggestion I made was accepted. But my purpose here is to illustrate how this consultation proceeded and how opponents of community water fluoridation (CWF) tried to swamp it with their submissions.

The background

Last November the Ministry of Health (MoH), through Medsafe, called for submission on a change to the Medicine Regulations 1984. This change had been recommended by the High Court and the Crown Law Office who specifically suggested that fluoride compounds used for CWF be exempt from definition as a “medicine.” This arose from the defeat of attempts by an anti-fluoride group, New Health NZ, to use the argument that fluoridation was medication in the High Court actions against CWF. Despite these defeats the High Court and Crown Law Office considered the regulations should be clarified to remove the argument from repeated litigation.

Simply, the proposal was to add a new regulation:

“Fluoride-containing substances, including the substances hydrofluorosilicic acid (HFA) and sodium silico fluoride (SSF) are not medicines for the purposes of the Act when they are manufactured and supplied or distributed for the purpose of fluoridating community water supplies.”

Medsafe asked for responses to the following questions:

• Question 1: Do you support the proposed amendment? If not why not?
• Question 2: Are there other fluoride-containing compounds used to treat community water supplies that should be specifically named in the regulation? If so, what are they?

Submissions – quantity or quality

The report from MoH on the process and their recommendations to cabinet give an idea of the submissions made and the final decision.

As we might expect from past experience the submissions were dominated, in numbers if not quality and relevance, by those from the anti-fluoride groups. They had organised a national and international campaign to swamp Medsafe. Paul Connett’s Fluoride Action Network, Fluoride Free NZ and New Health NZ even provided texts and templates to copy and paste into submissions.

Here is the description of the consultation outcome in the MoH report:

So, the activist organisations can certainly mobilise their forces for submissions. But concentration on numbers and not content – and cynical provision of content to followers anyway – didn’t win them any credence. Did they really think blatant duplication of submissions would not stick out like a sore thumb?

It is also heartening to see that the MoH was not swayed by blanket repetition of arguments which do not have credible scientific support. (I guess we can also see why the anti-fluoride activists groups are putting so much effort into their campaign to attack and discredit the NZ Fluoridation Review which summarises the scientific evidence.)

Sometimes suggestions are accepted

I had made the simple suggestion tha sodium fluoride be added to the short list of examples of fluoride chemicals used for CWF. So this recommendation to cabinet pleased me

Nice to know that the consultation was not a sham and that reasonable and credible suggestions were listened to and even accepted. It is worth making submissions even when one is aware they me in a minority. If something is worth saying it should be said despite attempts by others to confuse issues.

Also nice to know that some consultations are not simply swayed by quantity and not quality – as was the case for the Hamilton City Council fluoride consultation in 2013 (see When politicians and bureaucrats decide the science).

The Hamilton City Council consultation also showed an extreme naivety in the Council’s willingness to ignore the established science. I wonder what approach they would have taken if the NZ Fluoridation Review had been available at the time?

Similar articles

From dental neglect to child abuse?

Talk about conflicts of  interest!

The article, Children’s Health: Shift focus to care of young – MPs,  in yesterday’s NZ Herald really sparked a response in me: 

It opens with this:

“Cross-party inquiry comes up with strong message for change from emphasis on caring for people late in life.

 New Zealand must change its health-care priorities from the last two years of life to the womb if it is to improve its record on child health and child abuse, an inquiry has found.

More than half the Government’s $14 billion health budget goes towards caring for people late in life.

The parliamentary health committee says this is contrary to widely accepted research which shows that it would make more economic and social sense to do the exact reverse by focusing on the period between pre-conception and 3 years of age.”

So here I am – at the stage of life where our government is investing half its health budget. Yet my experience cries out to me that the suggested change of emphasis makes sense – for the good of individuals and society.

Most people agree we have to do something about child poverty, child neglect and child abuse in this country. Re-prioritising social health investment would go a long way to doing that. Surely its a no-brainer – look after the health of our children and we get healthier adults in the future who will be more resistant to health problems – even in old age. Investing in the health of children is an investment in the future of all ages – and the health of society in general.

The report

You can download the report which has the rather long title – here

It is actually a report from the NZ Parliamentary Health Committee. The Committee make specific recommendations in it and the report now goes to the government for consideration.

A sample of the chapter headings gives an idea of the report’s scope:

• The economics of early intervention with children
• Pre-conception care and sexual and reproductive health
• Social economic determinants of health and wellbeing
• Improving nutrition and reducing obesity and related non-communicable diseases
• Alcohol, tobacco, and drug harm
• Maternity care and post-birth monitoring
• Leadership, whole-of-government approach, and vulnerable children
• Immunisation
• Oral health
• Early childhood education
• Collaboration, information sharing, and service integration
• Research on children

I have only read part of the report so far so will just comment here on the Oral Health chapter – being quite relevant at the moment.

It introduces the problem with:

“Oral disease is among the most prevalent chronic diseases in New Zealand and among the most preventable in all age groups. We heard that oral disease and their consequences, such as embarrassment, pain, and self-consciousness, can have a profound effect on a person’s quality of life and ability to gain employment. Millions of school and work hours are lost globally to pain and infection from dental disease and the time needed to treat them. Caries can also affect children’s development, school performance, and behaviour, and thus families and society in general. Promoting good oral health benefits children of all
ages.”

True – but I would add the effects of poor oral health in childhood have repercussions right through life – even effecting the quality of one’s life in old age. I see this as a specific example of how investment in children’s health will reduce health costs for the elderly in the future.

Many causes of poor oral health

The report says the “risk factors and indicators for dental caries:”

” include socioeconomic deprivation, suboptimal fluoride exposure, ethnicity, poor oral hygiene, prolonged infant bottle feeding, poor family dental health, enamel defects, and irregular dental care.”

It expresses concern, and frustration, about the situation with availability of fluoridated drinking water:

“At present approximately only 55 percent of New Zealanders receive optimally fluoridated reticulated drinking water and coverage has recently decreased following decisions from the local councils in New Plymouth and Hamilton to cease fluoridating their water supplies. No substantial increases in coverage have occurred for over two decades.”

Its recommendations in this chapter include two about fluoridation:

102 We recommend to the Government that it work with the Ministry of Health to ensure that the addition of fluoride to the drinking water supply is backed by strong scientific evidence and that ongoing monitoring of the scientific evidence is undertaken by, or for, the Ministry of Health, and that the Director-General of Health is required to report periodically to the Minister of Health on the status of the evidence and coverage of community water fluoridation.

This is already happening to an extent with the National Fluoride Information Service and I hope their work continues and possibly expands. Scientific knowledge is always improving so it is important that we keep and eye on research findings and adjust health policies if, and when, necessary.

103 We recommend to the Government that it work with Local Government New Zealand and the Ministry of Health to make district health boards responsible for setting standards around water-quality monitoring and adjustments to meet World Health Organisation standards (or their equivalent), including the optimal level of fluoridation of water supplies. Part of the work programme would be to ensure that costs imposed on councils relating to standards and monitoring, are realistic and affordable. This should be implemented within two years of this report being published.”

It will be interesting to see how the government reacts to this recommendation. Fluoridation has become a bit of a political football for local bodies. This is not good because local body councillors can often have minority viewpoints and tend to be more easily influenced by ideologically motivated political activists. It seems more responsible that such important health issues are handled centrally by bodies with health expertise.

Dental neglect is child neglect

Another recommendation in the Oral Health chapter struck a chord with me:

“109 We recommend to the Government that “dental neglect” be defined as an important category of child neglect and recognised and managed accordingly. Systems must be established for following up children who do not attend scheduled appointments, and therefore risk pain from dental abscesses and untreated decay.”

Considering the consequences of child dental neglect I fully endorse that recommendation. Perhaps I would go even further – my reading having encouraged me to think of child neglect as a form of child abuse.

Perhaps we should admit that child dental neglect is a form of child abuse?

Similar articles

Welcome counter to scientific and health misinformation

Anti-fluoridation activists work very hard to propogate their misinformation. Letters to the editor, Facebook, Twitter and blog comments. At times their material will dominate google searches. No wonder the layperson can be confused, or even influenced by some of this information.

So I welcome the announcement of a new website dedicated to correcting the misinformation. This will provide New Zealanders a place to go for information on fluoride and fluoridation when they or their communities are faced with questions or even decisions. Interestingly, it is probably fairly unique in New Zealand – on-line action by authorities to counter misinformation about science and health.

Here is the media release about the new website from the Minister of Health Tony Ryall.

---

A new website, www.fluoridefacts.govt.nz will help local communities make informed decisions on water fluoridation, Health Minister Tony Ryall says.

The most recent nationwide New Zealand survey into oral health showed 40 percent less tooth decay on average for children living in fluoridated areas compared with non-fluoridated areas, Mr Ryall says.

“Some information circulating about community water fluoridation is either confusing or misleading. This website, which is supported by the Ministry of Health, district health boards and the New Zealand Dental and Medical Associations, contains evidence-based information, backed-up by research.”

New Zealand’s Chief Science Advisor, Professor Sir Peter Gluckman is among the several health professionals, scientists and community leaders who feature in a video series on fluoride also on the website. Professor Gluckman says: “It’s absolutely clear that the levels of fluoride that are put into New Zealand’s water supply – and are clearly regulated – are safe. They have real health benefits and there are no health risks.”

Mr Ryall noted that fluoride occurs naturally in water but New Zealand, like several other countries, has low levels. “Many countries in similar situations supplement fluoride to optimum levels for dental health benefit by adding it to the community water supply, or in some cases milk or salt.”

In New Zealand the levels of fluoride used in community water fluoridation are carefully monitored and within the guidelines of the World Health Organization and other public health agencies.

Mr Ryall says tooth decay, which is less likely in individuals when fluoride is added to the water supply, is painful and costly when fillings are needed to treat it. Community water fluoridation is effective, safe and an affordable way to provide the dental health benefits to everyone in a community.”

“People should refer to www.fluoridefacts.govt.nz  and come to their own conclusions when deciding to support community water fluoridation.”

For further information, including videos from Chief Science Advisor, Professor Sir Peter Gluckman, Chief Medical Officer of Health Dr Don Mackie, Chief Dental Officer Dr Robyn Haisman-Welsh and Children’s Commissioner Dr Russell Wills, along with other health experts and community leaders, see: www.fluoridefacts.govt.nz.

---

Further information also available from www.Health.govt.nz and www.nfis.org.nz the National Fluoride Information Service.
In New Zealand community water fluoridation is endorsed by the following organisations:

Ministry of Health
District Health Boards
New Zealand Dental Association
New Zealand Medical Association
Public Health Association of New Zealand
New Zealand Nurses Organisation
Te Ao Marama – the Māori Dental Association
Toi Te Ora – Public Health Service
Office of the New Zealand Children’s Commissioner
New Zealand College of Public Health Medicine
NZ Dental and Oral Health Therapists Association
NZ Society of Hospital and Community Dentistry
NZ Oral Health Clinical Leadership Network Group
Royal New Zealand Plunket Society
Cancer Society of New Zealand
The Royal Australasian College of Physicians
Royal Australasian College of Dental Surgeons

See also:

Similar articles on fluoridation
Making sense of fluoride Facebook page
New Zealanders for fluoridation Facebook page

Fluoridation – an organised campaign to misinform.

Credit: World Congress for freedom of scientific research

In my article Poisoning the well with a caricature of science I mentioned the anti-fluoridation activists in the US using a conscious strategy of casting doubt on the science. It strikes me this is also a conscious strategy used by local activists on this subject.

They are dong this by making unjustified claims about the nature of the fluoridation chemicals, the possible toxic effects of fluoride and the efficacy of fluoridation in limiting tooth decay. In the series of articles I have written on this blog there are a number of clear examples where scientific findings have been distorted or completely misrepresent in the anti-fluoridation propaganda. See, for example: Is fluoride an essential dietary mineral?, 
Fluoridation – are we dumping toxic metals into our water supplies?, Fluoridation – it does reduce tooth decay, Fluoridation – topical confusion, Fluoridation and conspiracy theories.

Internet, newspapers and local bodies

The outright distortions are being disseminated by a very active and organised letter writing campaign on the internet, to newspapers and to local bodies. Because of the responsibility of local bodies for water supply these activist organisations see them as a key target in their misinformation campaign. Soften them up with letters, get a hearing of submissions which they dominate (quantitatively but not qualitatively) and then get a decision to stop fluoridation. Hamilton was just such an example.

A short note on a recent posting at the Fluoride Action Networks Facebook page gives an idea of how this misinformation can work. This is a reply the network got from the Manawatu District Council:

“Thank you for your submission on the fluoridation of the Council’s water supply. Council is interested in your arguments and believe they warrant closer examination. Council also believes that the Ministry of Health’s pro-fluoride position should be reviewed. However, Council does not believe it has the expertise to evaluate the evidence itself.”

I think this is quote revealing for several reasons:

1. The council recognises they do not have the expertise to check the evidence they are getting from the anti-fluoridation network (or anywhere else, presumably). Seems sensible – call in the experts.
2. Despite this lack of expertise they have concluded that the Ministry of Health’s “pro-fluoride” position should be reviewed. (I can only imagine this was because of peroieved public pressure as they lack any expertise).
3. There is an implication that perhaps the Ministry of Health’s expert advice should be discounted because they are “pro-fluoride.” Hence a false balance between the expert’s scientific advice and the activist’s misinformed and distorted “science.”

We saw all these factors in the Hamilton example.

The council and the Mayor admitted they did not have the expertise to judge the evidence. They even passed a resolution asking for these sorts of decisions to be made by central government.

Despite this acknowledgement they went ahead and set themselves up as a tribunal to review and make decisions on the science! Several councillors justified the decision by repeating  some of the pseudoscience they had been dished up as if it were fact. They now consider themselves experts on the subject!

Some councillors also discounted correspondents who took issue with their interpretations, and the very bodies with the expertise – the Ministry of Health and the District Health Board. Some councillors have gone as far as suggesting that limitations should somehow be placed on the ability of these bodies to communicate with Hamiltonians during the buildup to the October fluoridation referendum!

I don’t necessarily blame members of councils for getting into this position. After all, they are given the responsibility to make the decision. And their concepts of community consultation can easily be distorted when activists groups with international backing come in from outside with a highly organised campaign to misinform them

But really the Hamilton experience should make other New Zealand councils suspicious of these campaigns. After all, this council did come out against the views of its citizens demonstrated in the 2006 referendum and in more recent polling. Consequently they came in for a certain amount of ridicule from local media and commenters for their anti-fluoridation decision.

The fight back

I hope councils will also take on board the warning of the Minister of Health about this issue. Tony Ryall warned councils and communities that:

“There will be people who come from out of town and tell all sorts of shock-horror stories around fluoridation.

“Communities need to know that that’s part of the strategy that these groups run, and they should look to their local district health boards, their local dentists and the evidence which shows that fluoridation in NZ is safe and does benefit families.”

This week’s NZ Listener editorial (The fluoride debate) described the anti-fluoridation campaign as “clever and bellicose” and warned “the anti-fluoridation lobby saw the win [in Hamilton] as a stepping stone to the likes of Auckland and Wellington.”

According to this editorial the Minister of Health has “ordered officials to marshal the strong scientific case for both the health benefits and safety of fluoridation in strengthening and protecting teeth against decay.” He sees an increased responsibility for the Ministry of Health, and probably district health boards, to counter the anti-fluoridation misinformation campaign.

Personally I think this is an important response – but it still suffers from being seen as a battle between institutions and grass-roots activists. There is a limit to the amount of initiative such institutions can take.  We need more scientific and health experts to also be seen, by name, opposing and exposing this misinformation.

See also:

debunking anti-fluoridation arguments
Fluoridation

Similar articles