Sunday, 14 September 2014

International reading comparisons: is England really doing so poorly?

I was surprised to see a piece in the Guardian stating that "England is one of the most unequal countries for children's reading levels, second in the EU only to Romania". This claim was made in an article about a new campaign, Read On, Get On, that was launched this week.

The campaign sounds great. A consortium of organizations and individuals have got together to address the problem of poor reading: the tail in the distribution of reading ability that seems to stubbornly remain, despite efforts to reduce it. Poor readers are particularly likely to come from deprived backgrounds, and their disadvantage will be perpetuated, as they are at high risk of leaving school with few qualifications and dismal employment prospects. I was pleased to see that the campaign has recognized weak language skills in young children as an important predictor of later reading difficulties. The research evidence has been there for years (Kamhi & Catts, 2011), but it has taken ages to percolate into practice, and few teachers have any training in language development.

But! You knew there was a 'but' coming. It concerns the way the campaign has used evidence. They've mostly based what they say on the massive Progress in International Reading Literacy Study (PIRLS), and the impression is they have exaggerated the negative in order to create a sense of urgency.

I took a look at the Read On Get On report. The language is emotive and all about blame: "The UK has a sorry history of educational inequality. For many children, this country provides enormous and rich opportunities. At the top end of our education system we rival the best in the world. But it has long been recognised that we let down too many children who are allowed to fall behind. Many of them are condemned to restricted horizons and limited opportunities." I was particularly interested in the international comparisons, with claims such as "The UK is one of the most unfair countries in the developed world."

So how were such conclusions reached? Read On, Get On commissioned the National Foundation for Educational Research (NFER) to compare levels of reading attainment in the UK with that of other developed countries, with a focus on children approaching the last year of primary schooling.

Given the negative tone of "letting down children", it was interesting to read that "In terms of its overall average performance, NFER’s research found England to be one of the best performing countries." I put that in bold because, somehow, it didn't make it into the Guardian, so is easy to miss. It is in any case dismissed by the NFER report in a sentence: "As a wealthy country with a good education system, that is to be expected."

The evidence of the parlous state of UK education came from consideration of the range of scores from best (95th percentile) to worst (5th percentile) for children in England. Now this is where I think it gets a bit dishonest. Suppose there were a massive improvement in scores for a subset of children, such that the mean and highest scores went up, but with the lowest scoring still doing poorly; presumably, the shrill voices would get even shriller, because the range would extend even further. This seems a tad unfair: yes, it makes sense to stress that the average attainment doesn't capture important things, and that a high average is not a cause for congratulation if it is associated with a long straggly tail of poor achievers. But if we want to focus on poor achievers, let's look at the proportion of children scoring at a low level, and not at some notional 'gap' between best and worst, which is then translated into 'years' to make it sound even more dramatic.

The question is how does England compare with other countries if we just look at the absolute level of the low score corresponding to the 5th percentile. Answer: not brilliant – 16th out of the 24 countries featured in the subset considered by the NFER survey. But, rather surprisingly, we find that the NFER survey excluded New Zealand and Australia, both of whom did worse than England.

So do we notice anything about that? Well, in all three countries, children are learning English, a language widely recognized as creating difficulty for young readers because of the lack of consistent mapping between letters (orthography) and sounds (phonology). In fact, when looking for sources for this blogpost, I happened upon a report from an earlier tranche of PIRLS data, which examined this very topic, by assigning an 'orthographic complexity' score to different languages. The authors found a correlation of .6 between the range of scores (5th to 95th percentile again, this time for 2003 data) and a measure of complexity of the orthography. I applied their orthography rating scale to the 2011 PIRLS data and found that, once again the range of reading scores was significantly related to orthography (r = .72), with the highest ranges for those countries where English was spoken – see Figure below. (NB it would be very interesting to extend this to include additional countries: I was limited to the languages with an orthographic rating from the earlier report).
PIRLS 2011 data: range of reading attainment vs. orthographic complexity
International comparisons have their uses, and in this case they seem to suggest that a complex orthography widens the gap between the best and worst readers. However, they still need to be treated with caution. I haven't had time to delve into PIRLS in any detail, but just looking at how samples of children were selected, it is clear that criteria varied. In particular, there were differences from country to country in terms of whether they excluded children who were non-native speakers of the test language, and whether they included those with special educational needs. Romania, which had the most extreme range of scores between best and worst, excluded nobody. Finand, which tends to do well in these surveys, excluded "students with dyslexia or other severe linguistic disorders, intellectually disabled students, functionally disabled students, and students with limited proficiency in the assessment language." England excluded "students with significant special educational needs". Needless to say, all of these criteria are open to interpretation.

I'm not saying that the tail of the distribution is unimportant. Yes, of course, we need to do our best to ensure that all children are competent readers, as we know that poor literacy is a major handicap to a person's prospects for employment, education and prosperity. But let's stop beating ourselves over the head about this. Research indicates that the reasons for children's literacy problems are complex and will be influenced by the writing system they have to learn (Ziegler & Goswami, 2005) and constitutional factors (Asbury & Plomin, 2013), as well as by the home and school environment: we still have only a poor grasp of how these different factors interact. Until we gain a better understanding, we should of course put in our best efforts to help those children who are struggling. The enthusiasm and good intentions of those behind Read On, Get On are to be welcomed, but their spin on the PIRLS data is unhelpful in implying that only social factors are important.

Asbury K, and Plomin R. 2013. G is for genes: The impact of genetics on education and achievement. Chichester: Wiley Blackwell.

Kamhi AG, and Catts HW. 2011. Language and Reading Disabilities (3rd Edition): Allyn & Bacon.

Ziegler JC, & Goswami U (2005). Reading acquisition, developmental dyslexia, and skilled reading across languages: a psycholinguistic grain size theory. Psychological bulletin, 131 (1), 3-29 PMID: 15631549

Friday, 29 August 2014

Replication and reputation: Whose career matters?

Some people are really uncomfortable with the idea that psychology studies should be replicated. The most striking example is Jason Mitchell, Professor at Harvard University, who famously remarked in an essay that "unsuccessful experiments have no meaningful scientific value".

Hard on his heels now comes UCLA's Matthew Lieberman, who has published a piece in Edge on the replication crisis. Lieberman is careful to point out that he thinks we need replication. Indeed, he thinks no initial study should be taken on face value - it is, according to him, just a scientific anecdote, and we'll always need more data. He emphasises:"Anyone who says that replication isn't absolutely essential to the success of science is pretty crazy on that issue, as far as I'm concerned."

It seems that what he doesn't like, though, is how people are reporting their replication attempts, especially when they fail to confirm the initial finding. "There's a lot of stuff going on", he complains "where there's now people making their careers out of trying to take down other people's careers".  He goes on to say that replications aren't unbiased, and that people often go into them trying to shoot down the original findings and this can lead to bad science:
"Making a public process of replication, and a group deciding who replicates what they replicate, only replicating the most counterintuitive findings, only replicating things that tend to be cheap and easy to replicate, tends to put a target on certain people's heads and not others. I don't think that's very good science that we, as a group, should sanction."
It's perhaps not surprising that a social neuroscientist should be interested in the social consequences of replication, but I would take issue with Lieberman's analysis. His depiction of the power of the non-replicators seems misguided. You do a replication to move up in your career? Seriously? Has Lieberman ever come across anyone who was offered a job because they failed to replicate someone else? Has he ever tried to publish a replication in a high-impact outlet? Give it a try and you'll soon be told it is not novel enough. Many of the most famous journals are notorious for turning down failures to replicate studies that they themselves published.  Lieberman is correct in noting that failures to replicate can get a lot of attention on Twitter, but a strong Twitter following is not going to recommend you to a hiring committee (and, btw, that Kardashian index paper was a parody).

Lieberman makes much of the career penalty for those whose work is not replicated. But anyone who has been following the literature on replication will be aware of just how common non-replication is (see e.g. Ioannidis, 2005). There are various possible reasons for this, and nobody with any sense would count it against someone if they do a well-conducted and adequately powered study that does not replicate. What does count against them is if they start putting forward implausible reasons why the replication must be wrong and they must be right. If they can show the replicators did a bad job, their reputation can only be enhanced. But they'll be in a weak position if their original study was not methodologically strong and should not have been submitted for publication without further evidence to support it.  In other words, reputation and career prospects will, at the end of the day, come down to the scientific rigour of a person's research, not on whether a particular result did or did not cross a threshold of p < .05.

The problem with failures to replicate is that they can arise for at least four reasons, and it can be hard to know which applies in an individual case. One reason, emphasized by Lieberman,  is that the replicator may be incompetent or biased.  But a positive feature of the group replication efforts that Lieberman so dislikes is that the methods and data are entirely open, allowing anyone who wants to evaluate them – see for instance this example. Others have challenged replication failures on the grounds that there are crucial aspects of the methodology that only the original experimenter knows about. To those I recommend making all aspects of methods explicit.

A second possibility is that a scientist does a well-designed study whose results don't replicate because all results are influenced by randomness – this could mean that an original effect was a false positive, or the replication was a false negative. The truth of the matter will only be settled by more, rather than less replication, but there's research showing that the odds are that an initial large effect will be smaller on replication, and may disappear altogether - the so-called Winner's Curse (Button et al, 2012).

The third reason why someone's work doesn't replicate is if they are a charlatan or fraudster, who has learned that they can have a very successful career by telling lies. We all hope they are very rare and we all agree they should be stopped. Nobody would make the assumption that someone must be in this category just because a study fails to replicate.

The fourth reason for lack of replication arises when researchers are badly trained and simply don't understand about probability theory, and so engage in various questionable research practices to tweak their data to arrive at something 'significant'. Although they are innocent of bad intentions, they stifle scientific progress by cluttering the field with nonreplicable results. Unfortunately, such practices are common and often not recognised as a problem, though there is growing awareness of the need to tackle them.

There are repeated references in Lieberman's article to people's careers: not just the people who do the replications ("trying to create a career out of a failure to replicate someone") but also the careers of those who aren't replicated ("When I got into the field it didn't seem like there were any career-threatening giant debates going on"). There is, however, another group whose careers we should consider: graduate students and postdocs who may try to build on published work only to find that the original results don't stand up. Publication of non-replicable findings leads to enormous waste in science and demoralization of the next generation. One reason why I take reproducibility initiatives seriously is because I've seen too many young people demoralized after finding that the exciting effect they want to investigate is actually an illusion.

While I can sympathize with Lieberman's plea for a more friendly and cooperative tone to the debate, at the end of the day, replication is now on the agenda and it is inevitable that there will be increasing numbers of cases of replication failure.

So suppose I conduct a methodologically sound study that fails to replicate a colleague's work. Should I hide my study away for fear of rocking the boat or damaging someone's career? Have a quiet word with the author of the original piece? Rather than holding back for fear of giving offence it is vital that we make our data and methods public: For a great example of how to do this in a rigorous yet civilized fashion I recommend this blogpost by Betsy Levy Paluck.

In short, we need to develop a more mature understanding that the move towards more replication is not about making or breaking careers: it is about providing an opportunity to move science forward, improve our methodology and establish which results are reliable (Ioannidis, 2012). And this can only help the careers of those who come behind us.

Button, K., Ioannidis, J., Mokrysz, C., Nosek, B., Flint, J., Robinson, E., & Munafó, M. (2013). Power failure: why small sample size undermines the reliability of neuroscience Nature Reviews Neuroscience, 14 (6), 365-376 DOI: 10.1038/nrn3475

Ioannidis, J. (2005). Contradicted and Initially Stronger Effects in Highly Cited Clinical Research JAMA, 294 (2) DOI: 10.1001/jama.294.2.218

Ioannidis, J. (2012). Why Science Is Not Necessarily Self-Correcting Perspectives on Psychological Science, 7 (6), 645-654 DOI: 10.1177/1745691612464056

Saturday, 23 August 2014

Labels for unexplained language difficulties in children: We need to talk

The view from the Tower of Babel
This week saw the publication of a special issue of the International Journal of Language and Communication Disorders, focusing on labels for children with unexplained language difficulties. Two target articles, one by Sheena Reilly and colleagues, and one by me, are accompanied by an editorial by Susan Ebbels, twenty commentaries, and a final paper where Sheena and I join forces with Bruce Tomblin to try to synthesise the different viewpoints. These articles are free for anyone to access.

Terminological battles are often boring and seldom come to any consensus, so why are we putting time into this thorny issue? Quite simply, because it really matters. As we argue in the articles, having a label affects how a children are perceived, what help they are offered, and how seriously their problems are taken. 'Specific Language Impairment' has very poor name recognition compared to dyslexia and autism, despite being at least as common. Furthermore, unless we can agree on some common language, it's difficult to make progress in research, and to discover, for instance, the underlying causes of language difficulties, how common they are in different parts of the world, or what interventions work.

I was first confronted with the full extent of the problem when I tried to analyse the amount of research and research funding associated with different developmental disorders (Bishop, 2010). There are other conditions, notably autism and dyslexia, where there is plenty of debate about diagnostic criteria, or even about whether the condition exists. But even so, the terminology is reasonably consistent. For children's language difficulties, this is not the case - they can be described as cases of language difficulty, disorder, impairment, disability, needs or delay, with various prefixes such as 'developmental', 'specific' or 'primary'. Some researchers will use such labels with precise meanings, often excluding children who have co-existing conditions, whereas others use them more descriptively. This made it extremely difficult to do a sensible internet search to estimate the amount of research funding associated with children's language difficulties.  

The confusion over labels has, I think, also contributed to the lack of public recognition of language difficulties in children. A couple of years ago, I joined together with Courtenay Norbury, Maggie Snowling, Gina Conti-Ramsden and Becky Clark with the goal of remedying this situation. We started a campaign for Raising Awareness of Language Learning Impairments (RALLI) (Bishop et al., 2012), and set up a YouTube channel to provide basic information. We spent some time debating what terminology to use: "Language learning impairment" was our preferred choice, but many of our videos talk of Specific Language Impairment, simply because that is a more familiar label. The lack of an agreed label proved a real stumbling block for our attempts at public engagement, and we decided that, as well as producing videos, one of our goals would be to get the terminology issue discussed more widely, in the hope of achieving some consensus. It was a very happy coincidence that Sheena Reilly and colleagues were crystallizing their own position on this question in an article in IJLDC, and that they, and the Editors, were willing to include my article, and the commentaries of other RALLI founders, in the published debate.

One thing that came across when reading commentaries on our articles was the disconnect between research and practice. One point on which I agree with Sheena and colleagues is that there is no justification for drawing a distinction between children whose language problems are comparable with below average nonverbal ability, and those who have a mismatch between good nonverbal skills and low language. Research has failed to find any difference between children with uneven or even nonverbal-verbal profiles in terms of responsiveness to intervention or underlying causes. Such a distinction is, however, widely used in educational and clinical settings to decide which children gain access to extra support in school.  Another issue raised by the Reilly et al paper is whether it is logical to use other exclusionary criteria, and to distinguish, for instance, between children who do and don't have autistic features in association with a language problem.  

As Susan Ebbels noted in her editorial, in everyday settings "diagnostic labels and criteria were being used creatively in disputes over access to services both by those seeking to obtain services for children (often parents and their lawyers) who could be accused of ‘diagnostic shopping’ and also by those seeking to deny services (often due to financial constraints) who may use particularly restrictive criteria in order to reduce the number of children qualifying for services". 

We can't afford to ignore this confused situation any longer. The time has come to have a wider debate on these issues, with the aim of reaching a consensus about how terms are used. The Royal College of Speech and Language Therapists has set up a moderated discussion forum where people can give their views on the best way forward. Please do consider adding your voice: it is important that all those affected by this issue have a say, whether you are a speech-language therapist/pathologist, psychologist, teacher, health professional, legal expert, policymaker, a parent of a child with language difficulties, or someone who has experienced language difficulties. We'd also love to hear from those outside the UK - whether English-speaking or not. You can access the discussion forum here.

Finally, to raise awareness of this debate, during the week of 24th-31st August I will be taking over  the @WeSpeechies Twitter handle as guest curator. On Tuesday 26th at 8.a.m. BST there will be a live twitter debate on this topic. Feel free to join in, even if you aren't a regular tweeter.

Bishop, D. (2010). Which Neurodevelopmental Disorders Get Researched and Why? PLoS ONE, 5 (11) DOI: 10.1371/journal.pone.0015112  
Bishop, D., Clark, B., Conti-Ramsden, G., Norbury, C., & Snowling, M. (2012). RALLI: An internet campaign for raising awareness of language learning impairments Child Language Teaching and Therapy, 28 (3), 259-262 DOI: 10.1177/0265659012459467

Slides on this topic are available here.

Addendum Friday 29th August 2014

We've had a great week of interactions on Twitter. A transcript for the week is available here.
I'll look through this and aim to organise the material in due course, but meanwhile would encourage anyone who is interested to continue the discussion on Twitter. I'm appending below some tweets that I generated throughout the week to generate debate.

As noted above, the chat links in to a special issue of the Internat. J Lang. Comm Dis which is free to access here  NB it is not all that obvious but there are 10 commentaries after each target article.

If you want to join the discussion on Twitter, feel free to comment at any time, but, please include the #WeSpeechies hashtag, so we can aggregate comments easily. Also if your comment relates to a numbered question, please add Q1, etc so we can relate them.

Monday started with my attempt to summarise each of the  twenty commentaries in a Tweet-length message.

Summaries from commentaries

Paediatricn Gillian Baird: ICD &DSM classifications talk of 'language disorder'; implies distinct from normal variation.  Disorder’ used for conditions without obvious aetiology; functional effect described separately in ICFDH.

Lauchlan/Boyle, ed psych view. Must ask: ‘Will label change the child's life for the better? Aetiology often irrelevant

Bellair et al: community SALTs. No one label works for both research & clinical. SLI has problems but we can manage them.

Mabel Rice: "SLI has yet to receive widespread adoption in clinical practice, in spite of the great need for it." critical of DSM5: excluded "well-researched category of SLI", included SCD, "with a minimal research base"

Kate Taylor SLP. SLI underidentified. Changing the term won't resolve the issue, which is one of measurement rather than label.

Conti-Ramsden: Any Consensus Panel on terminology must be international and include voices from different languages,

Hansson et al: ICD10 labels don't map on to use by researchers in Sweden . : Sweden: phonological & grammatical difficulties seen as part of language impairment. Soc comm probs separate

Clark & Carter: Survey:Scottish SALTs unclear re terms & diagnostic criteria. Move from exclusionary to inclusionary criteria.

Hüneke & Lascelles Concern that watering down terminology will mean kids lose scarce resources. Prefer medical term 'developmental dysphasia' that gets problems taken seriously

Strudwick/Bauer Concern that labels don't capture comorbidities; most ch with 'SLI' have other problems

Michael Rutter, psychiatrist "both clinical & research classifications needed but they require a different approach"

Rutter: Specific’ implies ‘pure’ language impairment; "not supported by any of the available evidence"

Larry Leonard: Many researchers already use broader definition of SLI: do not use term to mean children have a pure profile. communicatn with the public/other disciplines will be even harder if we adopt generic label ‘language impairment.

Snowling: DSM5 treats Communication Disorders separately from Specific Learning Disorders, yet they often co-occur

Aoife Gallagher,SALT; ethical issue:"who owns diagnosis once it has been given.. who ultimately has the right to take it away"

Andrew Whitehouse: ‘SLI’ provides neat criteria for researchers but label hides behavioural & aetiological heterogeneity

Dockrell/Lindsay Educational perspective re SLI is missing yet day-to-day support of learning/development provided by teachers. in England ‘speech, language & communication needs’ (SLCN) indicates primary need is with language & communication

Grist & Hartshorne: Children & young people we work with rarely describe selves as having SLI or SLCN

Norbury @lilaccourt Relaxing diag criteria will increase demand for services.SALTs shld focus on severe & persistent impairmts

Parsons et al @wordaware Shockwaves through SALT profession if nonverbal IQ criteria and delay/disorder distinction removed .Use of marketing approaches to development of a new term, including consultation with parents & young people.

Wright: legal perspective Much time spent in tribunal appeals arguing re labels: eg is it delay or disorder, is it specific?

Questions for debate

On Tuesday we had a live twitter chat with four question topics, and later in the week, I added further numbered question. Here is the total list – we'd love to hear your thoughts on any or all of these:

Q1 What is your view on use of the diagnostic label SLI? Does it reflect a medical model and is this appropriate.

Q2 is What are appropriate criteria for identifying children's language problems

Q3; Should IQ, ASD features, hearing loss determine whether language-impaired children can access services?

Q4 What terminology is most appropriate for children who have unexplained language problems?

Q5 ICD11 will use'Developmental Language Disorder' and DSM5 uses 'Language Disorder'. What do people think of these terms?

Q6 In research SLI still widely used but without requiring IQ discrepancy. Should we retain SLI but with this broader meaning, or is it just confusing?

Q7 In UK education, Speech, Language and Communication Needs (SLCN) is popular term. Is it used outside UK? Is it useful?

Q8 In UK clinical practice, distinction between language 'delay' & 'disorder' is used, but it has no research support.  Where does delay/disorder distinction come from? How defined?

Q9 Is there any support for a return to the more medical term 'developmental dysphasia'?

Q10. Reilly et al and several commentators suggest we drop 'Specific' and use the term 'Language Impairment' instead .What wld be advantages (e.g. avoids unfair exclusion) and disadvantages (e.g. too broad)?

Q11 What do people think of terms 'Language Learning Impairment' or 'Primary language impairment'? '

Q12 Do diagnostic labels actually help children and families?

Q13 Shld terminology/diagnostic criteria be responsibility of speechies, or shld other professions & families have a say? Assumptions/practices seem v. different in education/medicine/psychology vs speech-language therapy/pathology

Q14 In yr area, who does intervention with kids whose language problems are associated with autism?

Q15 Some  people take pride in identifying themselves as dyslexic. Does this ever happen for kids with language problems? If not, why not?

Q16 Has anyone encountered situation where child not offered intervention bcs language problems attributed to social deprivation?

Q17 Insurance considerations seldom important in UK, but affect label use elsewhere. Do US insurers just require DSM?

Monday, 28 July 2014

A film review from 32,000 feet: Noah

I don't do long haul flights much. They wreck my frontal lobe function and leave me not only with a headache, but with a sense of befuddlement that can take a few days to abate. I also find that if I try to while away the time with work, or read a book, it just makes matters worse, so I am reduced to watching the films. And now at 32,000 feet en rpute to New York, I can think of nothing better to pass the time than to write a review of the film I have just seen, Noah.

I grew up enjoying epics such as the Ten Commandments (with memorable plague of frogs and parting of Red Sea), Samson and Delilah (where, according to one review "Victor Mature fits neatly into the role of the handsome but dumb hulk of muscle")  and the Last Days of Sodom and Gomorrah (this trailer tells you all you need to know). I expected something similar – an attempt at telling a Biblical story through film, but with use of CGI to create better special effects.  But this was more like a bizarre mix of Lord of the Rings, Harry Potter and Pirates of the Caribbean, with a touch of Eastenders thrown in. Although I jotted down occasional notes as I viewed it, this is my reconstruction from memory and so accuracy is not guaranteed, especially given the befuddled state in which I watched.

So at the start we have Noah's father wandering around a barren landscape with his son. We know he is a goodie because a wounded beast comes scampering into view, and although it is of ferocious appearance, Noah's dad approaches it and speaks gently to it and attempts to deal with its wounds. However, a band of evil men then appear. We know they are evil because they have shot the animal and explain that they intend to eat it, on the grounds that 'The Creator' (the word 'God' is never used, interestingly) has not provided adequately for them, and so they need to eat meat. Noah's dad disapproves and so they bump him off, while Noah looks on in horror. Flash forward, then to the next generation, where Noah and his wife and children are wandering the same dismal landscape. It's not clear what they live on, since they disapprove of eating animals, and there's no vegetation to be seen. They also have quite respectable, if drab, clothes, and one wonders how these were achieved, if animal skins are verboten.

However, one really does not need to worry too much about plausibility because it becomes clear that supernatural forces are at play. Noah communicates with the Creator through dreams in which he is under water surrounded by drowning creatures. He decides to consult his grandad, Methusalah (Anthony Hopkins as a cross between Sauron, Obi Wan Kenobe and a hobo), who lives alone in a quarry, apparently not doing much but just waiting to be consulted.

On the way there (or possibly the way back) the family find a place littered with bodies, from which they rescue a small girl who is wounded. Marauding hordes, very reminiscent of Orcs or whatever the marauding things in Lord of the Rings are, attack them and they seem doomed, but escape into an area that everyone fears to enter. This is because it is controlled by a group of giant monsters who look like cookie monsters  that have spent too long in the microwave. These quell the marauding hordes, but spare Noah and his family. Here the plot goes a bit awry. The cookie monsters are 'the Watchers' and seem to be angels who were cast out of Heaven at the time of the Fall. If I got it right (the drinks trolley turned up around this time and I was a bit distracted) they were cast out because they wanted to protect humanity, incurring the wrath of the Creator who was utterly disaffected with humanity after Eve chomped at the forbidden fruit. Nevertheless, they approve of Noah because he wants to do the bidding of the Creator. Slight logical disconnect there, I think, but hey, they're only cookie monsters.

Fast forward a few more years, and Emma Watson pops up. This was very confusing, because her behaviour and reactions were exactly as in the Harry Potter movies, in that she spent a lot of time chasing after the boys trying to get them to behave sensibly. One of them, Shem, looks like the one in Pirates of the Caribbean who isn't Jack Sparrow (rather a shame that Jack Sparrow himself didn't feature, especially once the ark got waterborne, when he could have come in handy). He fancies Hermione, which is hardly surprising, as she is the only female around apart from his mother. However, there is a problem. Hermione is barren because of the injuries she suffered as a child. Everyone seems to know this as a given fact, though one might have thought that a bit of tentative exploratory sex would have been worth a try. Brother number two, who, perhaps as a joke in this vegetarian family, is named Ham, is jealous that he hasn't got a woman.

Somewhere along the way Noah has another consultation with Methuselah and decides that the earth is going to be destroyed by the Creator because of man's wickedness, and that what is needed is an ark. He doesn't have much of a clue about design, because what he ends up with is a giant wooden portakabin which doesn't seem to have a hull. This could be a consequence of enlisting the help of the cookie monsters, whose intellectual powers seem quite limited. But the birds are impressed, and start flocking in. The previous evening I'd watched a documentary about penguins, and so the thought uppermost in my mind was that the ark would have had a massive problem with poo – certainly even a pair of penguins would be capable of creating a substantial problem if the documentary was to be believed. However, here the script-writer had a moment of genius – Noah's wife fumigated the ark with a substance that sent all animals to sleep – except humans.

Somewhere about this point, Russell Crowe confused us all acquiring a number one clipper and trimming his hair and beard. I initially thought he was a new villain, and only recognised him when he put his hoodie back on. Ham also seemed to have access to the clipper and remained clean shaven with a short haircut throughout, whereas Shem had flowing locks and a beard, albeit a tidy one. The state of the men's grooming was a dead giveaway to their ethical status in the film, as became apparent when, in a genius piece of casting, Ray Winstone suddenly cropped up as Cain, with very unkempt hair and beard, a band of evil followers, and a cockney accent.  For reasons hard to fathom, Cain wanted to enlist Ham, but Noah wasn't having any of that, so Cain settled for establishing a camp near to the ark. This was rather spectacularly filmed to resemble a scene of hell by Hieronymous Bosch, but without the giant ears, with was much screeching and wailing, indicative of the sorry state of social mores. Cain did however groom his beard into two birfurcated points, perhaps suggesting some attempt to reform.

Noah's wife realises that the ark plan has a fatal flaw, which is a shortage of fertile women. Off she goes to consult Methuselah, who emerges from his quarry to track down Hermione, and perform an instant gynaecological miracle with his magic touch. This is followed almost immediately by her indulging in wild passionate sex with Shem (hinted at, as this is a film suitable for children). Ham, meanwhile, has gone into Cain's encampment to find a woman.  However, no sooner has he done so when Cain instigates an uprising to attack and take over the ark, and in the course of this, Ham's woman is killed. Somehow, Cain has invented a form of bazooka gun, which proves effective against the cookie monsters, who die in a spectacular blaze of fireworks before ascending to heaven, apparently now forgiven by the Creator.

I was rather disappointed by the rain. I had expected lots of it, but what was shown seemed rather pathetic when compared to the floods in the UK earlier this year. Instead, though, we had great geysers of water shooting up out of the ground – a bit like a supercharged version of the fountains at Heathrow's terminal  5 – plus the odd tsunami.  In any case, the Creator achieved his aim of drowning everyone except those on the ark, which remarkably, floated upright despite its unpromising design. Unbeknown to Noah, however, Cain had managed to stow away on the ark, where he proceeded to demonstrate how utterly evil he was by eating the odd animal. He enlisted the help of Ham, who was especially cross with Noah for failing to rescue the woman he had found in a ditch.

Meanwhile, Noah was becoming increasingly deranged. He had decided that the whole point of the exercise was to save the animals but rid the world of man, because man would only despoil the planet again if allowed to live. It was therefore imperative that no new humans should be born. This was problematic because Hermione was pregnant. Now, if your father had just told you that he was enacting God's will to exterminate the human race, and you found that your wife was pregnant, what would you do? Well, Shem thought it a good idea to go and ask for his blessing. Bad move. Noah isn't having any of it: "If you bear a girl, in the moment of her birth I will cut her down" (Yup, this is verbatim dialogue). In fact, Hermione, as one might have anticipated, outperforms and delivers twin girls. Shem has decided to kill Noah to save his babies, around the same time that Cain has decided to kill him, saying "Your ark, your beasts and your women are all mine. I will build a new world in my image." Cain has also enlisted Ham as backup assassin. You would have thought that with these odds, Noah's fate would be sealed, but somehow in a confusing fight scene in which everyone dived in, Cain ended up dead and Noah very much alive and still hell-bent on killing the twins. But, guess what, when it came to it, he was unable to carry out the act. And at that point a dove landed on the ark with a twig in its beak, and everyone cheered up.

That was about it. They landed somewhere that looked like Scotland and settled down, and after a brief period of depression and drunkenness, Noah re-established good relations with his family, except for Ham, who wandered off into the wilderness, perhaps hoping to find a female survivor of the flood.

The weirdest part of all this was that although I found the whole thing hilarious, I felt offended by the film on behalf of religious people. It is a little known fact about me that in my teenage years I was a Sunday School teacher - and so I have an extensive if rusty knowledge of the Bible.  I found myself getting especially cross about the cookie monsters, thinking that it was a travesty of the Bible story to introduce all this supernatural stuff. And then I realised what a ridiculous thought that was.