Monday, 21 March 2011

Factors in overdiagnosis

Schizophrenia is meant to be a thing. It is meant to be definable and measureable. An individual who is not schizophrenic but is given the label is overdiagnosed by the labelling psychiatrist.

There is significant debate about what it is and what is the factor which makes it an illness. In fact the only factor is a biological componenet. In fact in an article on best practice for schizophrenia written by a Hong Kong psychiatrist they specify using brain scans. I didn't think this was possible yet because brain imaging in mental illness was not able to accurately identfy everyone. I'm not sure if it is a problem of over or underdiagnosis or both. I'm aware the problem is not there in neurological illnesses diagnosed using tests such as MRI scans.

Regardless of this the modern system is based on report of behaviour and understanding of patient communication by ther psychiatrist. Other factors are involved if a psychiatrist is doing their job properly, for example taking a patient and family history. Cultural and religious information are important too if making a high quality diagnosis which would have high inter-rated reliability was important in UK clinical practice.

It's not. Not in psychiatry anyway. The methods used by psychiatrists are borderline lunacy. One of them borders on using fashion sense as a diagnostic measure. I kid you not.

Every psychiatrist has a different understanding of what a diagnosis looks like. Many don't use the reference criteria. These are adhered to dogmatically in research studies but not in clinical practice.

What happens in clinical practice is rife under and overdiagnosis. It's all misdiagnosis the likes of which would not be tolerated in physical medicine.

Just one tiny example is how studies screen out patients with schizophrenia who have family members with schizophrenia when looking at clinical data. Though the evidence exists to show there is a hereditary/genetic component the pervasive knowledge of the effect in the psychiatric community has meant siblings of people with schizophrenia are more often diagnosed with schizophrenia when they shouldn't be. The results of the science have powerful effects on diagnosis trends, trends which shouldn't exist in real illnesses.

There are many other factors in this variance. A surprising result is a strong factor is where the psychiatrists studied psychiatry. After their learning period each alumini group continued the dogma of the individual teaching institution because at these institutions where psychiatrists actually spend time learning the stuff they learn isn't totally standardised. They don't stick to the research criteria's rigour in clinical practice and they're not taught standardised definitions of the concept.

And so onto the frequent overuse of the diagnosis of schizophrenia in black people and black men. They're also sectioned, drugged and forced into treatment than their white counterparts. This doesn't happen in their cultures native countries.

The model if schizophrenia has shifted significantly from the original biomedical one. NICE in the UK favour a stress vulnerability idea. They stick rigourosly to the standard model of pathologisation, one which I've ranted about in other posts. This model is meant to be robust to ethnic variation. At least PANSS is meant to be.

Psychiatry has accessed of being racist because of the disproportionate use of extreme treatments on black people. But many white psychiatrists reliably diagnose schizophrenia and concur with black psychiatrists.

These diagnoses wouldn't be concurrent with what a black or white psychiatrist from the Caribbean would diagnose and there is a reason.

Individual social learning is important in mental health. It's important to the mentally ill but an unrecognised importance is that of the person giving the label, the person who makes the judgement upon someone else's sanity and individuality's abberance.

By social learning I mean what we come to know from the environments of our growth. The cultures where we went to school and hung out. The people we met in life. What we learned about people from the people we've met in our lives.

Ask yourself? How do you come to experience people? How do you label them? What factors do you apply based on your own norms?

These social judgements are nothing which doctors should have anything to do with. Their meant to be bound by an oath of do no harm first. Medicine is not here to empower the whims of temporary fashions of behaviour as judged by some dominant clique.

That litte segue was me taking a little breather from what's an important point. A small rant to provide a little background to inform the relevance of what I'm trying to say.

Psychiatrists are doctors. This means they need to get into medical school. They need to get good grades and excel. They often to go private schools. They often come from rich, sheltered backgrounds. Those rare ones from poor backgrounds who make it as doctors are usually insanely driven and have no life.

As a group they live protected existences for their lives up until getting to medical school. It gets worse there. They are unlikely to see any black people. Especially at Oxford or Cambridge.

What's worse is those few black people and the lots of brown people they do meet are coconuts. This is a dereogatory term I am comfortable with. It is a person who is Westernised and far from their cultural roots in behaviour, norms and beliefs.

They never meet black, brown or people of any other skin colour from the ghetto. Not unless they do drugs, but that's a whole nuther story.

I've lived an unusual life in diverse communities. What I mean is my social learning is surprisingly high given my lack of social graces. I have experienced a privilege of wide experiences of people and cultures in the UK.

This social learning means I see a problem or the reason for a problem.

I'll be blunt. Much of the overdiagnosis is based on risk. This translates synonymously with fear of the angry black man or person. This isn't about racism though.

I have no fear of psychiatric patients just as I have no fear of black men and their hostility. I have had the privilege to live in poor areas where Afro-Caribbean (ugh. I hate that term. Propaganda bullshit.) Eastern European and Irish people live. I've seen aggressive people regularly. I've got no fear because they're of no harm to me. No more than any other person. They may be intimidating or look hostile but they pose no risk unless you give them a good reason.

I've met some very ...criminal people mostly in my youth. I never got involved in it but I learned about what poor people are like. They're more basic in many ways and it can be a quality. They still have the part of humanity which survives from the Savannah plains to the urban jungle, a mentality devoid in many affluent people who end up having kids who become doctors and psychiatrists.

The overdiagnosis problem in part is because psychiatrists lack the wisdom of having lived a full life with expansive social learning from the university of life and the school of hard knocks.

Me? I 'as got me PhD from there. Innit.

Thoughts on external flashes

Many amateur photographers eschew the external flash. Some do it on
principle. They chose to shoot only using natural light.

Professional photography is also about light and an external flash used
well is an essential part of their arsenal. Some use a few external
flashes to create studio-quality lighting setups on location. Others use
flash to soften shadows or to create interesting light in poor situatuions.

I admit I tend to shoot without flash most of the time. Natural light is
usually the best. Live music photography demands shooting without flash
to catch the interesting colours and the venue lighting's effect. There
are venues when even fast lenses and high ISOs aren't enough but the
photographer still needs to get the shot so flash is the only option.

Flash light can also be used creatively. One of the effects I
experimented is in the mode of light painting but uses tricks with the
lens. Using an external flash and a slow shutter speed I can create a
zoom blur effect by carefully zooming the lens while the shutter is
open. I went a bit further and tried rotating the camera while zooming
with the shutter open which produced highly unpredictable but
interesting and unusual results.

On a practical level an external flash is essential because most of the
photos required for paid work need well lit faces in difficult lighting
conditions. They can be wedding shots or corporate events. They all need
sharp shots. There's scope for artistic shots too but there's what the
customer expects which needs to be delivered upon. Sports and
photojournalism also require a flash. A flash bathes the subject in
light and ensures enough light to use lower ISO settings.

For commercial photography a flash is a must. There are a few options.
As always the manufacturer own-brand offers the best option. A Canon
580EX MkI, a flash I've owned, is very useful. It's powerful and can
zoom the flash in sync with the focal length of the lens. It connects
with the camera metering systems to offer superb flash metering accuracy
in the right hands.

The key advantage of any external flash is the tilt and swivel
capability. This allows the photographer to bounce the flash of other
surfaces. Direct flash is why flash photography gets a bad name. It
doesn't look right. Indirect flash, for example bounced off the ceiling,
can give a soft quality to the light. There are tricks to it, for
example recognising the colour and texture of the surface which is used
to bounce. Dark surfaces eat flash light.

When using direct flash external flashguns have an advantage over camera
flashes because they have larger flash areas further away from the lens.
The distance from the lens reduces the problem of red eye and the larger
area for the flash offers smoother light. There are many aftermarket
flash adapter devices which can soften the light even further, for
example portable softboxes for off-camera flashes.

A major advantage of an external flash is power and, for professionals,
fast recycle time. Power means a flash can reach half way across a
football pitch with a good lens and a moderate ISO. It means high
ceilings can be used to bounce the flash light or dark surfaces can
still be used to reflect flash light. Recycle time means the time
between flashes. The recycle time is important whether using fill in
flash during the day and rapidly shooting to ensure the perfect
expression or moment is captured or shooting live action sports and
needing that fast flash keeping up with the camera's fast shooting speed.

Some flashes feature a very useful ability - high shutter speed
synchronisation. This is usually only available on manufacturer branded
flashes, i.e. only Canon flashes on Canon cameras have this feature.
There is one exception from the independent manufacturer Metz and this
was released a few years ago so more independent manufacturer flashes
may have this capability too but it is standard with the own brand flashes.

All cameras have a maximum flash shutter speed. This is in the region of
1/200s and above on modern cameras. It sounds pretty high but modern
cameras have shutter speeds in excess of 1/8000s. To get these
ultra-high shutter speeds the shutter operates a different way.
Essentially rather than a single shutter moving across the film plane
the camera creates a window moving across. This window moves quickly but
flash light happens in the region of 1/50,000s and faster so only a
small part of the frame exposed by the moving window shutter will be
exposed by the flash.

The high speed sync system fires the flash repeatedly very quickly to
ensure the moving window is exposed evenly as it moves across the
film/sensor plane. It relies on the cmaera and the flash electronics
talking to each other. I think there was the problem that camera
manufacturers charge a lot to get the specification of the communication
system. The independent manufacturers reverse engineer the signals but
can't work out what the internal system is so when camera manufacturers
change it the advanced features stop working. Metz have overcome this
with a flash gun which can connect to a computer if the
software/electronics needs to be upgraded. It uses an EEPROM or an FPGA
or something so when the brand communication system is updated it can be
updated too.

As always price is a large factor in any buying process. I bought the
Canon 580EX MkI in a shop for about £350 a few years ago. It's a very
good flash. It has all the features and it's also very easy to use in
real world conditions. The minor problem with it is weakness in
construction and It broke at one point. Luckily the extended warranty
paid for a replacement. The 580EX Mk II is an excellent flash with all
the bells and whistles but it's very expensive.

The 4xxEX series offer many of the benefits with lower power and recycle
time. Offerings from Metz also compete because they offer all the
features of a Canon-brand flash. Some of their older designs and those
of Sigma don't offer high speed flash synchronisation. This may seem
like a minor problem but it's big one for commercial photography. There
are days when the sun is very bright so fill-in flash is essential to
reduce the harsh shadows. For portraits a wide aperture may still be
desirable to put the background out of focus but this is unattainable
even at the slowest ISO because the of the limited shutter speed without
high speed synchronisation. This is probably the only use I can think
of: soften shadows on bright days. It's useful for sports as well as
weddings and outdoor portraits. It means full control of aperture and
light is possible.

The Sigma flashes are considerably cheaper than the Canon ones. Their
flashes can compete with Canon's flagship in most aspect for the price
of a mid-range model like a 4xxEZ-series flash. They lack that one
quality of being able to be used in any lighting conditions. That's it.
The value of this is quite high though for photographers who know how to
use fill in flash to make take shots and how flash is useful for certain
applications.

For some people a cheap Sigma flash would offer a signifcant benefit to
their photography. The option to bounce the flash off surfaces makes for
much better flash light. It can also be used with much more creativity
than the flash units built into cameras. They offer a lot of value.

The one thing they don't offer is what the pros want. The little things
like recycle time make a difference. The better controls on the 580EX
make it a pleasure to use. The possibility to use the flash in all
situations where it might be needed means high speed flash sync is very
important and worth the premium. Metz now provide an alternative which
has better build quality too. There will be fewer available on Ebay than
the Canons. The professional models also offer other options, ones which
I've rarely used, such as stroboscopic flash. For creative photographers
these features offer new opportunities to experiment.


Further information on this extensive webpage
http://photonotes.org/articles/eos-flash/#controlling

And part 2
http://photonotes.org/articles/eos-flash/index2.html

Some information on Canon's range
http://en.wikipedia.org/wiki/Canon_EOS_flash_system#Speedlite_products

The cheapest alternative from Metz with high shutter speed synchronisation
http://www.metz.de/en/photo-electronics/product-families/system-flash-units/mecablitz-50-af-1-digital/product-information.html

New ones with high speed sync
http://www.dpreview.com/news/1008/10082005metz58af250af1.asp

Sunday, 20 March 2011

Measures are importand as are language and concepts

If you tell a lay person it is an antipsychotic their expectation, like any other learned person outside the field of endeavour, is that it removes the delusions and hallucinations of psychosis.

If this is not true then the use of the term is highly inappropriate. As is the use of the drug.

The neuroleptic was commonly known as a major tranquilser, a 'medication' which did not function to heal true biological differences but to effect behavioural change. In the modern day where the word antipsychotic is used to describe the major tranquiliser there is another; the chemical cosh.

The fundamental point is about words and language and concepts. The antipsychotic is not about reducing the aspect which patients want and the public percieve. It is a tool driven by the power to sedate.

It may or may not have a significant effect compared to placebo responses but no review of current data is available. It is possible without a new experiment though things like these ultimately answer scientific questions.

On the question of whether the antipsychotic actually, definitely reduces the delusions and hallucinations themselves or merely sedates the individual into a conveient form of limited expression is an important question for patients, and I hope doctors too.

To the doctors I will explain using evidence which may be questioned if you are critical of evidence. A study which showed life expectancy in elderly people with dementia was reduced by 50% when antipsychotics were used shows a powerful effect but as an observational study it explains little but the existence of the effect. The criticisms which can ameliorate the effect are to do with selection of patients to get antipsychotics. Their behaviour may have been the result of a more advanced stage of a neurodegenerative illness. The effect has high sensitivity because patients were near death too. The untranquilised lived 3 years on average. The medicated 1.5.

An obvious review which needs to be done

Right. I've had a few beers and smokes. Bear with me.

PANSS and BPRS are two of the measures of effectiveness of treatment in trials for schizophrenia. Only one of the measures within those supra-measures is delusions and hallucinations.

I think so anyway. I have to double check PANSS and check BPRS.

This idea may be obvious to a psychiatrist wh understands the multifaceted treatments and what they actually achieve based on the research evidence.

It's a guess on my part and perhaps their part that if a review of trials was done which drilled into the measures to pick out the sole measure patients who accept psychiatric treatment for mental illness want - the reduction of the specific symptom of hallucinations, delusions or alterntive experiences of consciousness - it would show consdierably less effectiveness to the point of insignificance comapred to placebo.

Why I'm so sure is I've read two stufies which I'm sort of join together as an effect. Medication works on a biomedical model backed by placebo controlled high quality studies. One piece of evidence is clozapine, the most dangerous psychiatric medication, only reduces the delusions in some patients. This is from a qualitative paper, hence the quantification using the word sum, written by the company which makes the drug and was published in the British Journal of Psychiatry.

The other bit of evidence is the Rosenthal study into expectations and teacher effects. What I took from the study is not what's commonly known. What's disseminated about this study is the author's conclusions. The effect of telling teachers kids were smart made them smarter. This is true. Except in older kids in the study. They seemed to be indifferent to this effect.

What if the effect on delusions is not what's achieved by major tranquilisers. What if this effect is only achieved by the effects of expectation by doctor and patient? What if it is a placebo effect and the sole purpose of 'antipsychotic' medication is to subdue a person to remove behaviour rather than treat the concept people know as psychosis?

And where are my chocolate salty balls? Oh. Sorry. Firmly in the mouths of the RCPsych.

I remember childhood depression and perhaps SAD

For about 9 or 10 months I worked as an assistant engineer at the National Remote Sensing Centre on a European Space Agency satellite called ENVISAT. I was 18 years old and got the role through the Year In Industry gap year scheme.

I worked far away from home. All the rest of my friends were at university. When I started I used to travel from home. It would be pitch black at 5am when I woke up and pitch black at 7 or 8 when I got home as the winter months set it. I moved down there for a couple of months but it was even worse than the commute so I moved back to this punishing routine.

I remember walking home in darkness, going straight to my room and putting some music on. I would sit in there only lit by candlelight. I would cry but for no reason. I'd shut myself away and cry then get out of my room and put on my mask of normality.

It used to feel bad in ways which are different to now. In those days that was just normal. I didn't even see it as misery let alone an illness. I went to posh schools and they teach resilience. The pain was something I accepted and continued to function. There were thankfully low expectations of an 18 year old but I exceeded them beyond their expectations.

I never felt suicidal. I never contemplated it. I just got through every day. I found my release back then was music. My only luxury was going on a Friday night to the record shop and buying the latest releases when they had just come out. Then i'd go home and listen to them on my own.

I didn't no any different. I'd lead a sheltered childhood till being thrown out of how briefly at the age of 15. I'd spent two subsequent years at boarding school. I'd done another job before helping a researcher sift through medical data. This was my first proper job though.

My dad had done a similar routine most of his working life. When I was growing up he worked his arse off to give me a good education. He used to rise at 5 or 5:30 and return at 7 in the evening or later. The poor guy had one luxury to get him through it all. He drank Johnnie Walker Black Label. he medicated through years of misery the likes of which I briefly tasted when I was 18.

He's a GP.

Are good photographers obsessive

Yes and no. There must be some who aren't but the attention to fine detail and perfectionism required of professional photgraphers means the photographers naturally obsess.

I've spend a long time thinking about the value of an f2.8 lens. The value is beyond the premium except when getting the shot is a priority. Sports photographers spend several thousands on digital SLRs which meet this need and if they're not good enough they change brand. Sometime the perfect light and moment appear briefly and if the camera or the photographer are too slow the moment's missed.

There are little things about the equipment which might not make sense to average users. Another thing I'm thinking about is high sync flash. What this means is an external flash can be used at any shutter speed. In practice this means flash can be used in daylight to soften shadows. Really that's the only purpose - total creative freedom no matter what the situation. The problem is it's a small difference in apparent and real value for some forms of photography. Live music photographers rarely use flash.

Spec-ing a photographers desktop PC

I've already written a post about this so I'll summarise the information.

Photographers have unique requirements for a desktop computer setup. Computing is now an essential part of the photographer's standard equipment. The desktop, for many, has been replaced by powerful laptop machines however these are not able to offer the performance or the specification for the perfect professional machine.

Image quality
Performance is in different areas. One of them is image quality. No flat panel screen at a reasonable price can beat the quality of output from an old cathode ray tube (CRT) monitor. These are large but even the cheapest ones offer superlative image quality required for professional work.

Of course a large screen monitor is useful too. I'd suggest a dual screen setup with a large flat panel and a CRT. The CRT is used to see the whole image - a feature easily achieved in most good photo editing packages. The large screen can be used for the detail work and where all the tool docks are shown. Good quality, large CRT screens are pretty cheap second hand though delivery is expensive. Over the years some may have lost the quality of focus. Their image quality - colours, contrast, resolution - will still usually be excellent. A modern flat panel with a 14" CRT makes a lot of sense though.

Large widescreen flat panels have dropped significantly in price. There are three technologies: TN, PVA (and the variants) and IPS. The are increasingly more expensive going from TN to IPS technology and in quality too. Large OLED monitors are not a commercial option. The three TFT technologies have dropped a lot in price and the quality of commerically available TN screens has risen significantly using colour profiles which can adjust the graphics output to counter the problems of TN screens. With the added bonus of a CRT screen a 24" TN-type panel with a 14" CRT screen provides a good value option. A PVA screen would be a better option but the differences are small. The price of these has also dropped significantly. IPS screens are still a significant premium and they're the benchmark for high end screens dedicated to photography, video and 3D.

Calibration is also important. This can significantly improve the value of a screen. The CRT screen provides an exceptionally high quality output however a custom calibrated flat panel can perhaps beat the quality of a CRT screen. It can come very close anyway. Calibration is signifcantly more expensive than a 14" CRT screen though (note the viewing area of these screens will be about 12").

One feature often little considered is the graphics card. Most people would assume that a fast graphics card isn't required for photography work. They're right. Even integrated motherboard graphics cards can handle the output of image manipulation. What people don't know is there's a difference in image quality between different cards. There's no way to measure this and it's rarely discussed in reviews of graphics cards.

I stumbled across this when I had two graphics cards installed in my system. One was running a cheap but modern graphics card from a little know brand. The other was an ancient Matrox Millenium.  People may not recognise the brand any more but a decade ago they were very well regarded in the graphics card industry. This was in the time before people considered 3D processing a reason to buy an expensive graphics card. The Matrox cards were designed for image makers. They offered other features like inexpensive access to two monitor setups with one card - something which is standard today. Hooked up to the same monitor the Matrox displayed significantly better image quality across all domains. It was a clearly visible difference which anyone could see.

This reason alone is why Apple are good computers. Though they don't offer the choice of components or the ease of tinkering with the hardware as well as being significantly more expensive they're worth it if you don't want to have to know which graphics card offers the right quality. Their monitors are a significant premium over other equivalents too. It is possible to make a £1,500 non-Apple computer setup which would perform about as well as a £4,000 Apple setup and offer other benefits.

Computer spec
The chips in desktop machines are faster than laptops and importantly they can be overclocked. This is a way to get more performance out of the same processor. Given how quickly processor prices can rise with increasing speed the option to overclock a chip quickly becomes a money saving solution. Photography doesn't need ultra-fast processing like 3D or video which can benefit from multi-processor and multicore designs. Dual core or processor is the maxium requirement and an overclocked low-to-mid processor should be enough for a year or two. It can also be replaced by a faster processor next year which offers much better value.

RAM, of course, is important for easy editing of multilayered high resolution files. Modern file sizes are massive. RAW files are 25MB+ from my Canon 50D and something like the 7D will output even higher quality files which need more RAM. I like to step up my RAM gradually and this is much easier with a desktop than a laptop. Quick RAM is useful for overclocking and can offer small speed benefits too but it's important to chose carefully because some of the more exotic forms of memory don't offer significant benefits for photography applications.

Someone who's used consumer cameras and consumer photo editing software may not have experienced a need for a quick processor or lots of RAM. In professional digital photography the file sizes and more demanding algorithms which offer the highest quality output and maximum control mean a decent processor is required. The images from a professional digital camera aren't just higher megapixels. The files have more detail and much wider dynamic range. They're usually processed from RAW - the digital negative - rather than JPEG. Professional photographers spent a lot of time working with the filters, tools and controls offfered in programs such as Photoshop or GIMP. There's a lot of tweaking involved and this can mean rerunning a filter. One of my favourites, selective guassian blur, can take 15-30mins to run on a laptop.

Keeping data safe
Apart from performance there's one key aspect of the design of a content producer's PC: the disk system. I've had 3 hard drives fail in my years of computing. That's three too many and I lost a lot of important data. It's very expensive to recover data from a disk where the head has crashed. RAID is the primary solution for people who use large files and lots of them. These can use many disks with one to protect the data from a single drive failure. These systems are available in ultra-highend laptops but come as standard on good motherboards. They're often no implemented on consumer or even standard business PCs because there's little demand for them or knowledge about them. The system is used in any server worth its salt. Not just for better reliability and fault tolerance but because it can offer more speed too. A few disks are relatively cheap and can create a work area which will last for a couple of years of digital photography.

I think 3 or 4 1TB disks in a RAID 5 configuration should be enough for that requirement but 2 1TB disks in RAID 1 (mirroring not striping) would suffice at a push. It sounds like a lot of data but I shoot RAW and use the highest quality for all my processed image files. A 16GB card on a modern camera can quickly fill up on a day long shoot. I don't waste a lot of time clearing out old photos. I like to go back to them and work on them again. I need a very large hard drive for that workflow.

On top of this there also needs to be geographical backup which for most people means backup to an online server. I used an Idrive account to backup all the uncompressed JPEG versions of my best images. If my computer is stolen or the house burns down my images are still safe. For people who use their computer for writing documents or anything which has small file sizes the Idrive solution is enough. It's easy to use and it's free. The information is stored on their computers and can be retrieved with the right details from any computer just like web-based email.

Peripherals
A keyboard and mouse are obviously essential but a graphics tablet can be a very useful addition. It makes editing the image a lot easier though I've learned to get by with a mouse and even a trackpad. The computer forms the basis of the photographer's lightroom and it still requires good physical tools.

Obviously a memory card reader, a few USB ports (and Firewire can be useful too) and wireless are important. These are cheap or come as standard.

Budget
It's possible to build a bespoke photographer's PC for about £1,000. £1,500 would be optimum. At a squeeze one can be built for £800 with all the above considerations taken into account. A £1,000 PC with a £500 investment in upgrades over a two year period would be suitable for professional photography at the lower end though £1,500 with £1,000 spent over the next two years would be better with cameras offering really large files and for photographers used to compositiing several images together, using focusing stacking or HDR techniques.

A laptop is yet another necessity for modern professional photography. More on that in another post.

About Me

We It comes in part from an appreciation that no one can truly sign their own work. Everything is many influences coming together to the one moment where a work exists. The other is a begrudging acceptance that my work was never my own. There is another consciousness or non-corporeal entity that helps and harms me in everything I do. I am not I because of this force or entity. I am "we"