Christian male modelling

Posted on January 28, 2016 by cedwardpitt

Some love him. Some hate him. It doesn’t change the fact that he was still “ridiculously good looking”.

Zoolander was one of those cult movies that polarised people into “absolutely love it” or “absolutely loathe it” camps. I admit, I’m one of the former. (“Moisture is the essence of wetness, and wetness is the essence of beauty” … It still cracks me up!)

For those who aren’t familiar with the story, Derek Zoolander was a top male model who was famous for his different looks: “Blue Steel”, “Ferrari”, “Le Tigre” and the famous “Magnum”. They were all the same pose, of course, but everyone thought they were different. Except for evil fashion designer, Mugatu, who in a burst of rage at the climax of the movie, yells, “Who cares about Derek Zoolander anyway? The man has only one look … Blue Steel? Ferrari? Le Tigra? They’re the same face! Doesn’t anybody notice this? I feel like I’m taking crazy pills!”

There are times when I read Dr Leaf’s social media posts, and I feel the same as Mugatu.

“Dr Leaf isn’t a scientific expert … ‘When we think, we learn because we are changing our genes and creating new ones’ … That’s not scientifically possible! Doesn’t anybody notice this? I feel like I’m taking crazy pills!”

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. If Dr Leaf was a legitimate scientist, she would know that our genes do not change when we process new information. Our genes are stable. They do not change unless there’s a mutation, which occurs in one out of every 30 million or so genes. We do not make new genes at will. Last year, scientists at MIT were reported to have shown that DNA breaks when new things are learnt, but in a normal nerve cell, these breaks are quickly repaired. That’s certainly interesting, but that’s not changing the DNA or making new genes. Making claims that we make new genes to hold new information is like saying that pigs fly.

Dr Leaf’s supporters would likely make a counter-argument that she probably didn’t mean that genes really change, or we make new genes, she’s just not worded her meme properly. Well, there are two responses to that, neither of which are any better for Dr Leaf. Because scientists who really are experts don’t make errors so large that you can spelunk through them. And, this isn’t the first time that Dr Leaf has made claims about how our genes fluctuate. She made a similar claim back in September 2014. Saying the same thing several times isn’t a mistake, it shows she really believes that we change our DNA code by the power of our thoughts.

Whether someone thinks DNA is changeable isn’t likely to cause any great harm to that person, but what is concerning is that Dr Leaf has been given her own show on the Christian cable TV network TBN to discuss mental health. She’s already proven that her knowledge of psychiatric medications is dangerously flawed. If Dr Leaf doesn’t know the basics of DNA, then giving her a platform to preach something that can effect whether a person might live or die is particularly perilous.

Dr Leaf’s rise is also a worrying symptom of a Christian church that is intellectually imploding. In a 2013 blog for the Huffington Post, Charles Reid wrote,

“Christians must provide effective witness against both extremes. But before Christianity can engage atheism it must first address the scientific illiteracy in its own house. For the greatest danger Christianity confronts at the present moment is not incipient persecution, but increasing marginalization and irrelevance. If Christians cannot engage reasonably and responsibly with science, there will be no place for them in the public life of advanced societies.”

Reid was paying particular attention to Ken Ham in this blog, but the principle remains the same. Scientifically illiterate Christians quickly lose credibility with people. We can’t meaningfully engage with a person who has a rudimentary understanding of biology by proudly tell them that we create new genes with the power of thought. That makes us sound like a male model.

For the sake of other Christians health and well-being, and for the sake of our credibility and our witness, we need to critically assess Dr Leaf’s work, not promote it as another gospel.

Dr Caroline Leaf and the genetic fluctuations falsehood

Posted on September 27, 2014 by cedwardpitt

While idling away on Facebook, as is my usual pass time, I came upon Dr Leaf’s Facebook feed. There were her usual self-indulgent holiday happy-snaps and another couple of Pinterest-style fluffy inspirational posts. Then this: “Our genetic makeup fluctuates by the minute based on what we are thinking and choosing”.

Dr Caroline Leaf is a South African born and trained, US based, communication pathologist. She also claims that she’s a cognitive neuroscientist. Given the quality of the posts on her social media pages recently, no one could ever take such a claim seriously.

To make sure we’re all clear about what she just said, I’m going to say it again: “Our genetic makeup fluctuates by the minute based on what we are thinking and choosing”. It was an astonishing, if not bewildering statement, especially coming from someone with a PhD level education. If Dr Leaf were a medical doctor and publically made a statement like that, her registration would be reconsidered.

The core of the statement, which pushes it so far beyond the boundaries of rational scientific thinking, is the phrase “Our genetic makeup fluctuates by the minute.”

DNA in our cells is like an old audio cassette tape. Audio cassette tape is a long magnetic stripe, storing the code which the tape player decodes as sound. DNA is a chemical string which has a sequence of “bases” off to the side. The full DNA molecule is made of two matching strings joined by chemical bonds between the bases (hence the name, “base pairs”). Depending on what the cell needs, it runs the DNA through a decoder to either copy it, or to ‘play’ it (i.e. using the information stored in the code to build new proteins).

Like the tape in an audio cassette, the code of the DNA is incredibly stable. The rate of DNA mutation is about 1 in 30 million base pairs [1]. DNA doesn’t ‘fluctuate’, (“rise and fall irregularly in number or amount” [2]). It’s not the stock market. The number of genes in each cell of my body does not rise or fall depending on whether I’m having a good hair day.

The other part of Dr Leaf’s statement, that our DNA “fluctuates … based on what we are thinking and choosing” is also scientific nonsense. The only way that your thoughts and choices are capable of inducing genetic mutations is if those thoughts or choices involve cigarette smoking or standing next to industrial sources of ionising radiation.

I think Dr Leaf is trying to say that our thoughts and choices can change our gene expression, which is the construction of new proteins from the instructions in the DNA code. However, gene expression has nothing to do with our thoughts and choices. IVF embryos are expressing genes like crazy as they grow from one cell to an embryo in just a petri dish. It doesn’t think or choose.

More often than not, our thoughts and our choices are the result of gene expression, not the cause of it. We don’t have any specific control over the process either. The process of genetic expression is dependant on a complex series of promoters and tags on the DNA, which are controlled by other proteins and DNA within the cell, not thought or choice.

The truth is that gene expression occurs moment-by-moment, regardless of what we think or don’t think, do or don’t do. Gene expression is simply DNA being read. Our genetic makeup, the DNA code, is stable. It does not fluctuate. There is no part of Dr Leaf’s statement that is scientifically accurate.

Ultimately, Dr Leaf continues on her pursuit of pseudoscience, an affront to the people who trust her to tell them the truth, and the God of all truth that she purportedly represents.

References

Xue, Y., et al., Human Y chromosome base-substitution mutation rate measured by direct sequencing in a deep-rooting pedigree. Curr Biol, 2009. 19(17): 1453-7 doi: 10.1016/j.cub.2009.07.032
Oxford Dictionary of English – 3rd Edition, 2010, Oxford University Press: Oxford, UK.

Dr Caroline Leaf and the genetic remodelling myth

Posted on August 29, 2014 by cedwardpitt

We are all slowly mutating!

Yep, it’s true. Not to the same extent as you might see in shows like X-Files or Dr Who, but still, our DNA is slowly accumulating permanent changes to the pattern of the genes that it contains. Thankfully, it’s only in science fiction that the mutations result in zombie apocalypse scenarios.

Dr Caroline Leaf is a Communication Pathologist and a self-titled cognitive neuroscientist. Still glowing from the unquestioning adulation of her faithful followers at the Switch On Your Brain conference last week, Dr Leaf has hit social media again. Most of her posts have been innocuous quotes that look borrowed from Pinterest, but today, Dr Leaf has ventured into the pseudoscientific again by claiming that, “Our genes are constantly being remodeled by our response to life’s experiences.”

Unless your response to life’s experiences is to stand next to an industrial microwave generator or live in a nuclear waste dump, Dr Leaf’s statement is pure fiction. Dr Leaf confuses the mutation of our genes with the expression of our genes.

The only way our genes actually change is through mutation. A mutation is a permanent change in the sequence of the DNA molecule. A genetic mutation is a permanent change in the DNA sequence that encodes a gene. DNA is constantly mutating, because of environmental damage, chemical degradation, genome instability and errors in DNA copying or repair [1: p97]. Still, the actual rate of DNA mutation is about 1 in 30 million base pairs [2]. So DNA is very stable, and changes for a number of reasons, only some of which are related to our external environment. And as I alluded to just before, slightly tongue-in-cheek, our responses are not the main contributor to these environmental influences, unless we deliberately expose ourselves to ionizing radiation or smoke cigarettes. Our DNA does not change because of our thought processes as Dr Leaf advocates [3].

What does change more readily is the expression of those genes. Gene expression is the cell machinery reading the genes and making the proteins that the genes encode. The genes are expressed to make the proteins needed for the cell to maintain its function. Which genes are expressed is dependant on the cell’s stage of development and the environment it finds itself in. For example, when the body encounters a high level of dietary iron, a series of steps activates a gene to promote the production of ferritin, a protein that helps to carry iron in the blood stream [1: p375-6]. Gene expression isn’t solely dependent on our environment though, because an embryo is expressing genes like crazy in order to make the proteins to build a human being, but the gene expression in an embryo is largely following a pre-determined time course, not the environment [4] (and certainly not because of responses to life’s experiences).

In summary, our genes are controlled by a myriad of different factors, nearly all of which have nothing to do with our responses or choices. Our genes are not changed by our choices or our responses. Our genes may be mutating, but God designed our cells with mechanisms to repair them. Our genes are not being remodelled by our responses. That’s the realm of science fiction.

References

Strachan, T. and Read, A., Human Molecular Genetics. 4th ed. 2011, Garland Science, New York, USA:
Xue, Y., et al., Human Y chromosome base-substitution mutation rate measured by direct sequencing in a deep-rooting pedigree. Curr Biol, 2009. 19(17): 1453-7 doi: 10.1016/j.cub.2009.07.032
Leaf, C.M., Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. 2013, Baker Books, Grand Rapids, Michigan:
Ralston, A. and Shaw, K. Gene Expression Regulates Cell Differentiation. Nature Education, 2008. 1(1): 127; http://www.nature.com/scitable/topicpage/gene-expression-regulates-cell-differentiation-931

Like to read more about Dr Leaf’s teaching and how it compares to current science? Download the free eBook HOLD THAT THOUGHT, Reappraising The Work Of Dr Caroline Leaf

Dr Caroline Leaf and the myth of optimism bias

Posted on January 10, 2014 by cedwardpitt

“What are little girls are made of? Sugar and spice, and all things nice.”

It sounds sweet doesn’t it? We like to connect with these rosy little memes that warm our cockles and make us feel good about the world and ourselves. We think of all of the examples in our own experience, which seems to confirm the saying. We may think of a few examples that don’t quite fit, but they’re just the exception that proves the rule.

It doesn’t seem to matter what the saying or proverb is, we usually just assume it’s true. Think of some other examples:
“Blondes have more fun.”
“Women can’t read maps.”
“White guys can’t dance.”

In all of these things, we tend to experience what psychologists call confirmation bias (Princeton University, 2014), our own mini-delusion in which we fool ourselves into believing a half-truth. It looks right on first glance, and we can easily think of a few confirming examples, so without deeper inspection, we assume it must be true.

When Dr Leaf proclaims that,

“Science shows we are wired for love with a natural optimism bias”

the same process kicks in. But in truth, science doesn’t show anything of the sort. What science shows is that we learn love and fear, and our genetics influences the way we see the world, our personality.

We are prewired to LEARN to love and fear. It doesn’t come naturally. We require exposure to both love and to fear for these emotions to develop. The Bucharest Early Intervention Project is a study looking at the long-term psychological and physical health of children in Bucharest, one group who remained in an orphanage, and the other, a group of children that were eventually adopted. Analysis of the cohort of the two groups of children showed that negative affect was the same for both groups. However positive affect and emotional reactivity was significantly reduced in the institutionalised children (Bos et al., 2011). This shows that children who lived in an institution all of their lives and given limited emotional stimulation had lower levels of positive affect (ie: love, happiness) compared to a child that was adopted.

The children in the institution did not have high positive affect because they were not shown love. Those children who were adopted were higher on positive affect because they were shown love by their adopted parents. Both groups were exposed to distress and fear during their time in the orphanage, so their negative affect was the same across both groups. Thus, love and fear don’t come naturally. They need to be learned.

Personality is “the combination of characteristics or qualities that form an individuals distinctive character.” (“Oxford Dictionary of English – 3rd Edition,” 2010) As Professor Greg Henriques wrote in psychology today, “Personality traits are longstanding patterns of thoughts, feelings, and actions which tend to stabilize in adulthood and remain relatively fixed. There are five broad trait domains, one of which is labeled Neuroticism, and it generally corresponds to the sensitivity of the negative affect system, where a person high in Neuroticism is someone who is a worrier, easily upset, often down or irritable, and demonstrates high emotional reactivity to stress.” (Henriques, 2012) Personality is heavily influenced by genetics, with up to 60% of our personality pre-determined by our genes (Vinkhuyzen et al., 2012), expressed through the function of the serotonin and dopamine transporter systems in our brain (Caspi, Hariri, Holmes, Uher, & Moffitt, 2010; Chen et al., 2011; Felten, Montag, Markett, Walter, & Reuter, 2011).

So some people *ARE* natural optimists – their genetic heritage blessed them with a rosy outlook and their early life experiences cemented it in. These naturally optimistic people, and the people who know them, are the ones who take Dr Leaf’s word as truth because they see it in themselves or their friends. But the fact that some people are naturally wired for pessimism or a neurotic personality disproves Dr Leaf’s assertion.

Its important that Dr Leaf’s misleading meme is seen for what it is. If we assume that we’re all pre-wired for love and optimism, then those who are pessimistic must be deficient or deviant, and the fact they can’t change must mean they are incompetent or lazy. If we know the truth, those who are less optimistic won’t be unnecessarily judged or marginalised.

I should point out that what I’ve said isn’t a free licence to be cranky or sullen all the time. The natural pessimist still needs to be able to negotiate their way through life, and being a misery-guts makes it hard to get what you need from other people in any business, social or interpersonal relationship. We have the ability to learn, and the person with a neurotic personality can still learn ways of dealing with people in a positive way.

But if you naturally see the glass half-empty, don’t tell yourself that you’re abnormal, or that you aren’t good enough. You are who you are. Accept who you are, because while there are weaknesses inherent to having neurotic personality traits, there are also strengths, such as the enhanced awareness of deception, or protection from gullibility (Forgas & East, 2008).

A good thing to have when searching for the truth.

References

Bos, K., Zeanah, C. H., Fox, N. A., Drury, S. S., McLaughlin, K. A., & Nelson, C. A. (2011). Psychiatric outcomes in young children with a history of institutionalization. Harv Rev Psychiatry, 19(1), 15-24. doi: 10.3109/10673229.2011.549773

Caspi, A., Hariri, A. R., Holmes, A., Uher, R., & Moffitt, T. E. (2010). Genetic sensitivity to the environment: the case of the serotonin transporter gene and its implications for studying complex diseases and traits. Am J Psychiatry, 167(5), 509-527. doi: 10.1176/appi.ajp.2010.09101452

Chen, C., Chen, C., Moyzis, R., Stern, H., He, Q., Li, H., . . . Dong, Q. (2011). Contributions of dopamine-related genes and environmental factors to highly sensitive personality: a multi-step neuronal system-level approach. PLoS One, 6(7), e21636. doi: 10.1371/journal.pone.0021636

Felten, A., Montag, C., Markett, S., Walter, N. T., & Reuter, M. (2011). Genetically determined dopamine availability predicts disposition for depression. Brain Behav, 1(2), 109-118. doi: 10.1002/brb3.20

Forgas, J. P., & East, R. (2008). On being happy and gullible: Mood effects on skepticism and the detection of deception. Journal of Experimental Social Psychology, 44, 1362-1367.

Henriques, G. (2012). (When) Are You Neurotic? Retrieved from http://www.psychologytoday.com/blog/theory-knowledge/201211/when-are-you-neurotic

Oxford Dictionary of English – 3rd Edition. (2010) (3rd edition ed.). Oxford, UK: Oxford University Press.

Princeton University. (2014). Confirmation bias. Retrieved January 10, 2014, from http://www.princeton.edu/~achaney/tmve/wiki100k/docs/Confirmation_bias.html

Vinkhuyzen, A. A., Pedersen, N. L., Yang, J., Lee, S. H., Magnusson, P. K., Iacono, W. G., . . . Wray, N. R. (2012). Common SNPs explain some of the variation in the personality dimensions of neuroticism and extraversion. Transl Psychiatry, 2, e102. doi: 10.1038/tp.2012.27

Autism Series 2013 – Part 3: The Autism “Epidemic”

Posted on September 4, 2013 by cedwardpitt

Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4.

It seems that autism is on the rise. Once hidden away in institutions or just dismissed as odd, society is now faced with a condition that it is yet to come to grips with. Some out in the community believe that it must be a toxin, or vaccines or mercury. Others accuse doctors of simply giving in to the unreasonable demands of pushy parents to defraud the system of money – “Things have reached the point these days where any kid that’s not a charming little extrovert will be accused of being, ‘on the spectrum.’”[1]

So is there an epidemic of kids who are “not charming little extroverts”? It depends on who you ask.

Take, for example, two articles written in the year 2000. In the first, titled “The autism epidemic, vaccinations, and mercury”, Rimland said,

“While there are a few Flat-Earthers who insist that there is no real epidemic of autism, only an increased awareness, it is obvious to everyone else that the number of young children with autism spectrum disorders (ASD) has risen, and continues to rise, dramatically.”[2]

The other, written by Professor Tony Attwood, a world authority on Aspergers Syndrome, said,

“… is there an epidemic of people being diagnosed as having Asperger’s Syndrome? At present we cannot answer the question, as we are unsure of the diagnostic criteria, the upper and lower levels of expression and the borders with other conditions. Nevertheless, we are experiencing a huge increase in diagnosis but this may be the backlog of cases that have been waiting so long for an explanation.”[3]

I don’t think it’s very often Prof Attwood is lumped with ‘flat-earthers’. But you can see the change in perspective from one side looking objectively to the other who need for there to be an “epidemic” of autism in order to strengthen their case.

So who’s right? To see if this autism “epidemic” hypothesis has any real merit, we need to delve into some numbers.

First, some basic epidemiology – because part of the confusion in looking at the autism numbers is defining exactly what those numbers represent. Here are some important epidemiology terms from the “Physicians Assistant Exam for Dummies”[4]:

Incidence: For any health-related condition or illness, incidence refers to the number of people who’ve newly acquired this condition.

Prevalence: Prevalence concerns the number of people who have this condition over a defined time interval.

Most autism figures are for prevalence, or often more specifically, point prevalence – “the number of people who have this condition at any given point in time.”

The other thing to remember from my last blog is that initially autism was only diagnosed on the strict rules of Kanner, and was considered to be a single disease caused mainly by bad parenting [5]. So through the 1960’s and 1970’s, only the most severe children were diagnosed as having autism because the high-functioning autism would not have met Kanners criteria, and even if they did, most parents didn’t want the label for fear of the social stigma.

So then, what are the numbers? The early prevalence was estimated to be less than 5/10,000 or 1 in 2000[6], although in surveys done after 1987, the numbers began to rise past 7/10,000[7]. In the 1990’s, Autism prevalence climbed into the teens and the latest prevalence has been documented for autism is 20.6/10,000[7].

But that’s only about 1 in 485. The CDC estimated a prevalence of 1 in 88 (113/10,000)[8]. Where did the other 400 people go?

This is where the importance of definitions is highlighted. Autism is considered part of a spectrum, and at the time of the surveys reviewed by Fombonne, DSM III then DSM IV considered conditions like Pervasive Developmental Disorder and then Aspergers Disorder to be part of that spectrum. Adding in the rate of PDD and you have a figure of 57.7/10,000 and adding in Aspergers gives you a combined rate of 63.7/10,000, or 1 in 157 people surveyed[7].

And yet even then, who you measure and how you measure makes much more of a difference, because a recent, rigorous study targeting all 7 to 12 year old children in a large South Korean populous found a prevalence of 2.64%, which is 264/10,000 or 1 child in every 38. The authors noted that, “Two-thirds of ASD cases in the overall sample were in the mainstream school population, undiagnosed and untreated. These findings suggest that rigorous screening and comprehensive population coverage are necessary to produce more accurate ASD prevalence estimates and underscore the need for better detection, assessment, and services.”[9]

So if there has been a fifty-fold change in prevalence (from 5 to 264 cases per 10,000 people) in just thirty years, isn’t that an epidemic?

Well, no. As much as some might ignorantly deny it, there is no real evidence for it. Remember the definitions from the “Physicians Assistant Exam for Dummies”[4]:

Incidence: For any health-related condition or illness, incidence refers to the number of people who’ve newly acquired this condition.

Prevalence: Prevalence concerns the number of people who have this condition over a defined time interval.

It’s the rapid rise in the number of new cases diagnosed that defines an epidemic, which is the incidence and not the prevalence[10]. While the prevalence has changed a lot, the incidence has been fairly stable. From Nature, “Christopher Gillberg, who studies child and adolescent psychiatry at the University of Gothenburg in Sweden, has been finding much the same thing since he first started counting cases of autism in the 1970s. He found a prevalence of autism of 0.7% among seven-year-old Swedish children in 1983 and 1% in 1999. ‘I’ve always felt that this hype about it being an epidemic is better explanation’, he said.”[11]

Fombonne agrees. “As it stands now, the recent upward trend in estimates of prevalence cannot be directly attributed to an increase in the incidence of the disorder.”[7] He said later in the article that a true increase in the incidence could not be ruled out, but that the current epidemiological data which specifically studied the incidence of autism over time was not strong enough to draw conclusions.

While there’s no epidemic, there is the real issue of the genuinely increasing prevalence. Why the rise in those numbers? Fombonne went on to explain, “There is good evidence that changes in diagnostic criteria, diagnostic substitution, changes in the policies for special education, and the increasing availability of services are responsible for the higher prevalence figures.”[7] Nature published a graph from the work of Professor Peter Bearman, showing that 54% of the rise in the prevalence of autism could be explained by the refining of the diagnosis, greater awareness, an increase in the parental age, and clustering of cases in certain geographic areas.

Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4. (Adapted from King, M. and Bearman, P., Diagnostic change and the increased prevalence of autism. International Journal of Epidemiology, 2009. 38(5): 1224-34 AND King, M.D. and Bearman, P.S., Socioeconomic Status and the Increased Prevalence of Autism in California. Am Sociol Rev, 2011. 76(2): 320-46.)

From Nature: “The fact that he still cannot explain 46% of the increase in autism doesn’t mean that this ‘extra’ must be caused by new environmental pollutants, Bearman says. He just hasn’t come up with a solid explanation yet. ‘There are lots of things that could be driving that in addition to the things we’ve identified,’ he says.”[11]

There is no autism epidemic, just medical science and our population realising just how common autism is as the definition becomes more refined, people become more aware, and some other biosocial factors come into play.

What can we take from the numbers? That we’re being overtaken by Sheldon clones? That soon there will be no more “charming little extroverts”? If the CDC figure is accurate, then one person in every hundred is on the spectrum, so the world is hardly being overtaken by autism. But the take home message is that Autism Spectrum Disorders are more common that we ever thought, and there are more people on the spectrum “hiding in plain sight”. If the study from South Korea is accurate then one person in every thirty-eight is on the spectrum, but two thirds of them are undiagnosed.

Should there be more funding, more resources, or more political representation for people on the spectrum? Perhaps, although the public and research funds are not unlimited, and other health concerns should also be treated fairly. But since autism is life long and impacts on so many areas of mental health and education, understanding autism and managing it early could save governments billions of dollars into the future.

Rather, I think that the climbing prevalence of ASD is a clarion call for understanding and tolerance. If we learn to tolerate differences and practice discretionary inclusion, then both the autistic and the neuro-typical can benefit from the other. That’s a world which we’d all like to live.

REFERENCES

1. Bolt, A. If the autistic don’t get full cover, where’s the money going? 2013 2013 May 11]; Available from: http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/if_the_autistic_dont_get_full_cover_wheres_the_money_going/.

2. Rimland, B., The autism epidemic, vaccinations, and mercury. Journal of Nutritional and Environmental Medicine, 2000. 10(4): 261-6.

3. Attwood, T., The Autism Epidemic: Real or Imagined, in Autism Aspergers Digest2000, Future Horizons Inc: Arlington, TX.

4. Schoenborn, B. and Snyder, R., Physician Assistant Exam For Dummies. 2012: John Wiley & Sons.

5. Pitt, C.E. Autism Series 2013 – Part 2: The History Of Autism. 2013 [cited 2013 2013 Aug 15]; Available from: https://cedwardpitt.com/2013/08/15/autism-series-2013-part-2-the-history-of-autism/.

6. Rice, C.E., et al., Evaluating Changes in the Prevalence of the Autism Spectrum Disorders (ASDs). Public Health Reviews. 34(2).

7. Fombonne, E., Epidemiology of pervasive developmental disorders. Pediatric research, 2009. 65(6): 591-8.

8. Baio, J., Prevalence of Autism Spectrum Disorders: Autism and Developmental Disabilities Monitoring Network, 14 Sites, United States, 2008. Morbidity and Mortality Weekly Report. Surveillance Summaries. Volume 61, Number 3. Centers for Disease Control and Prevention, 2012.

9. Kim, Y.S., et al., Prevalence of autism spectrum disorders in a total population sample. American Journal of Psychiatry, 2011. 168(9): 904-12.

10. “Epidemic vs Pandemic”. 2013 [cited 2013 Sept 03]; Available from: http://www.diffen.com/difference/Epidemic_vs_Pandemic.

11. Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4.

Dr C. Edward Pitt

Faith, Hope, Love, Science.

Tag Archives: science

Christian male modelling

Dr Caroline Leaf and the genetic fluctuations falsehood

Dr Caroline Leaf and the genetic remodelling myth

Dr Caroline Leaf and the myth of optimism bias