Talking therapies for depression are overrated thanks to publication bias

DepressionAn analysis of studies into counseling therapies for depression – such as cognitive-behavioural therapy – has found that the effect of such approaches has been overestimated because studies that show a strong effect of the treatments are getting published over studies with more modest results.

In 117 studies, “talking therapies” had an average effect of 0.67 on symptoms of depression, with zero being “no effect,” whereas once publication bias was taken into account this effect dropped to 0.42.

Publication bias is “the tendency for increased publication rates among studies that show a statistically significant effect of treatment.” Think about it – patients, researchers and editors are going to be more interested in studies showing that a treatment has a considerable effect on a condition than those showing that the treatment has only a negligible effect. As a result, those studies showing a strong effect either way – that a treatment is really good or really useless – are more likely to get published and the effect of a therapy gets overestimated.

Publication bias is known to affect studies on the effects of antidepressant medications: trials showing that a drug works are more likely to get published than those showing that it doesn’t work. This is due in no small part to the pharmaceutical companies that fund drug research wanting to promote the most positive outcome possible for the medications that they sell.

Now a new analysis by Cuijpers et al. has found a similar effect among studies about psychotherapy for depression – only the most dramatic findings are getting out there and as such the effects of “talking therapies” are being “talked up.”

The authors looked at published studies on psychological treatments for depression – either approaches where verbal communication between a therapist and a client was the core element or in which a patient independently worked through a treatment book with some kind of personal support from a therapist.

They found a total of 117 studies that compared 175 treatment conditions with a control condition. When they calculated the effect of treatment in each study and analysed all these numbers together, the mean treatment effect for psychotherapy compared with control was 0.67, with zero being “no effect.”

The authors then undertook several types of statistical tests to determine whether the studies in their analysis were subject to publication bias.

The mean effect dropped to 0.42 once all the data had been adjusted for publication bias, and the various tests all pointed strongly to bias. The authors point out that effect sizes of 0.80 can be assumed to be large, effect sizes of 0.50 are moderate, and effect sizes of 0.20 are small.

Interestingly, no indication of publication bias was found for studies examining interpersonal psychotherapy, which targets how the patient interacts with other people, or for studies examining psychotherapy for women with postpartum depression.

The authors then looked specifically at the much vaunted approach cognitive-behavioural therapy, where therapist focuses on the impact a patient’s present dysfunctional thoughts have on current behaviour and future functioning. The overall effect size of the 89 comparisons between cognitive-behavioural therapy and a control condition was 0.69, but this value was reduced to 0.49 after adjustment for publication bias.

The authors conclude that research on psychotherapy for adult depression does not seem to be any freer from publication bias than research on medication treatment. As they say, “Pharmaceutical companies have clear financial reasons to inflate research findings, and psychological investigators have both personal and professional reasons for doing the same.”

The implications for this analysis are pretty messy – the research suggests that one of the two most important treatments for adult depression is not as effective as assumed, bad news given that “talking therapies” are generally thought to work better than pharmaceutical approaches, the other top therapy.
Cuijpers P at el. (2010) Efficacy of cognitive-behavioural therapy and other psychological treatments for adult depression: meta-analytic study of publication bias. The British Journal of Psychiatry 196 (3): 173-178. DOI: 10.1192/bjp.bp.109.066001

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Hot housed Chinese schoolkids are getting ill from the stress

Chinese schoolchildrenA third of Chinese children experience high levels of school-related stress, and these kids are about five times more likely to have the physical symptoms of stress – that is, headache or abdominal pain – then their less frazzled peers.

Thanks to the combination of China’s recent economic growth – with the increased opportunities for upward mobility – and the vast numbers of people competing for each university place and job, Chinese children are under pressure to do well right from the start of primary school.

A cross-sectional study published in Archives of Disease in Childhood has now shown the negative effects this relentless pressure can have on children’s health.

The study was carried out on more than 2,00 children aged 9-12 years in nine schools in urban and rural areas of Zhejiang, a relatively wealthy coastal province in the east of China.

Nearly a fifth said they rarely enjoyed school, with boys less likely to enjoy school than girls. A total of 81% said they worried “a lot” about exams, and 78% felt under pressure to perform well at school “all the time.”

In particular, the punitive nature of school in China comes across in this study: 44% of children were always afraid of being punished by their teachers. Furthermore, 71% said they were physically punished by their parents at least sometimes. No wonder these kids were so worried about doing well.

When it came to the psychosomatic symptoms of stress, 67% of boys and 66% of girls reported headache at least once a week, whereas 60% of boys and 78% of girls has stomach ache that often.

As a comparison, a study of school stress in Swedish 10-13 year olds reported that 21% of boys and 30% of girls experienced headache and 17% of boys and 28% of girls experienced abdominal pain at least once per week.

Children who were the most stressed on all the measures looked at were 5.6 times more likely to experience headache and 4.9 times more likely to report abdominal pain than kids who were the least stressed. Being bullied was the individual stressor that was most strongly associated with psychosomatic symptoms.

The authors believe that their findings “reflect the high value placed on education in Chinese society, urban and rural, and the widespread belief in the possibility for upward social mobility through education.”

Piling so much stress onto such young children could be storing up problems for the future. Studies have shown that children who have high levels of anxiety and depression are likely to have psychological problems into adolescence and adulthood.

According to the authors, “Much of the stress in Chinese schools is unnecessary and has simply become incorporated into the system.” They recommend reducing the frequency of exams and the sheer volume of homework to make life a little less intense for kids.

Hesketh T et al. (2010) Stress and psychosomatic symptoms in Chinese school children: cross-sectional survey. Archives of Disease in Childhood 95 (2): 136-140. DOI: 10.1136/adc.2009.171660

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Music and the Mind: “can’t get it” and “can’t get it out of my head”

MusicWhen I was at the Science Museum Lates event this week, I attended a talk on the perception of music by researchers from the Music, Mind and the Brain group at Goldsmiths, University of London.

The first half of the talk was by Lauren Stewart, a cognitive neuroscientist, who outlined how the brain understands music.

Music is entirely a construct of the mind, she pointed out, because sound waves are simply vibrating air molecules, nothing more.  What is remarkable is not just that the brain understands how to interpret these sequences of molecules, but that we can also understand composites of several different strings of molecules interwoven together; i.e. the different musical elements – for example, guitarist, bass, drums, singer – that make up a song.

Activity of the brain when music is heardBut how did the brain evolve this ability?  One possibility is that music is a super stimulus for pleasure, said Dr Stewart.  The brain, she said, is adapted to recognise patterns. The process of hearing a song and predicting what comes next sets off the neurotransmitter dopamine in areas of the brain associated with other pleasure stimuli, like sex and drugs – suddenly the old adage “sex, drugs and rock’n’roll” makes more sense!  The “musical chills” that you experience when you hear a song you really like is a good example of this process in action.

Dr Stewart studies the disorder amusia, which is a lifelong failure to recognise familiar tunes or tell one tune from another. Sufferers frequently complain that music sounds like a “din” and often avoid social situations in which music plays a crucial role. Such individuals are unable to understand the up and down pitch of music, but have no problems with the pitch changes in speech, like rhythm, stress, and intonation.

Some people develop this problem after significant brain trauma, like a car accident, whereas others are born with it. Dr Stewart describes the genetic component of amusia, “congential amusia,” by highlighting a family of eight siblings from Northern Ireland, four of whom have amusia and four of whom hear music fine. In fact, a study of nine families with some amusic members and ten normal families found that 39% of first-degree relatives of amusic people have the same cognitive disorder, whereas only 3% have it in the control families.

By studying a “broken system,” Dr Stewart hopes to find out more about the “correct” cognitive architecture of music, and its relation to other cognitive skills such as language and spatial awareness. Her present research aims to elucidate exactly which perceptual and cognitive mechanisms are at fault in amusia, whether disordered musical processing has implications for language, and the extent to which such difficulties can impact upon sociocultural functioning.

The second half of the talk was by Daniel Müllensiefen, a computational scientist, who studies involuntary musical imagery, or “earworms.”

Prevalence of earmwormsAn earworm, a direct translation of the German word “ohrwurm,” is a portion of a song or other music that repeats compulsively within one’s mind – “I’ve got a song stuck in my head.” Earworms are related to voluntary musical imagery – earworm activate the same areas of the brain as when you’re listening to music.

Apparently, as many as 90% of people experience an earworm at least once a week, whereas about 50% have one everyday.  The average length an earworm is on repear is 27 minutes, and between 15% and 33% of people find these “cognitively infectious musical agents” unpleasant or disturbing.

Dr Müllensiefen is using computational analysis of music to determine what it is about a song that makes it stick in our heads and become an earworm. He and his team have broken down the melodies over 14,000 pop songs from the 1950s to the present day into sequences of 0s and 1s that computers can deal with.

They have then analysed the statistical distributions and regularities in the data from commercially successful songs to determine what elements make a song a hit. Apparently, what you need is a chorus melody that has a large range and uses only few pitches much more frequently than the majority of its pitches.  Which looks like this:Hit song equation

This talk was a great introduction to how the brain deals with music – both in instances where people can’t get a grip on music and in cases where they can’t get it to go away.

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British scientist conducts world’s first experiment on Twitter

twitter_logoProfessor Richard Wiseman,  psychologist at the University of Hertfordshire and author of Quirkology, is today undertaking the first ever scientific experiment to be conducted using Twitter.

The experiment is designed to test the existence of a psychic ability known as ‘remote viewing’ – the alleged ability to psychically identify a distant location.

Prof Wiseman is pretty skeptical about the possibility of psychic powers, but, as he notes, “the American government spent millions of dollars examining remote viewing and lots of people believe that it is a genuine ability”.

At 3pm GMT on Tuesday, Wednesday, Thursday and Friday this week, Prof Wiseman will travel to a randomly selected location in the UK. He will then ask all his Twitter followers to tweet about their thoughts concerning the nature of the location.

Thirty minutes later, he will provide online photographs of five locations (the actual location and four decoys) and followers will vote on which of the five spots they think is the actual target location.

If the majority of people select the correct target then the trial will count as a hit, otherwise it will count as a miss. Three or more hits in the four trials taking place this week will be seen as supporting the existence of extrasensory perception.

Speaking to the Daily Telegraph, Prof Wiseman says “three hits would be against odds of one in 125, which would be quite impressive” , although on his website he revises this statistic to 1 in 37.

Extra sensory perception, which includes remote viewing, was chosen as the subject of this study because of the interesting methodological issues involved, including blind judging, the elimination of subtle sensory cues, and randomness.  There is also a psychological dimension to the study because everyone is being asked to indicate their belief in the paranormal when they vote as to which location they believe is the true location, allowing Prof Wiseman and his team to look at differences between those who believe in psychic abilities and those who are skeptics.

As of today, 6,500 people have signed up for the experiment, although Prof Wiseman hopes that as many as 10,000 people will eventually take part.

Prof Wiseman has organised several mass participation experiments, not least LaughLab, a worldwide experiment to find the world’s funniest joke.

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Women judged on their appearance are considered less competent

Doesn't Sarah Palin look pretty in girly pink? Or does she look competent?A study published in the Journal of Experimental and Social Psychology has found that women judged solely on their appearance are marked out as less competent than those judged on a broader basis.

In this research, 133 undergraduates – 96 women and 37 men – were asked to judge either Republican vice-presidential nominee Sarah Palin or actress Angelina Jolie.  Half of the participants were asked to write a few lines on their “thoughts and feelings about this person”, whereas the other half were asked to write their “thoughts and feelings about this person’s appearance.” The students were subsequently asked to rate their subject in terms of various attributes, including competence.

Participants who wrote about Jolie’s or Palin’s appearance were more positive in their assessments than those who assessed their qualities as a person, but rated these two celebrities far lower in terms of competence, intelligence and capability. Interestingly, this trend applied to both men and women, as well as to liberals, moderates and conservatives.

The authors argue that women who are judged on the basis of their looks are construed as ‘objects’ and are subsequently perceived as less human.  Such objectification strips women of characteristics that are regarded as fundamental to being human, such as self determination and unique talents.  Without these key human traits, objectified women can easily be brushed aside and judged as incompetent

“Viewing another individual as low in human essence”, write the authors, “reflects a superficial, more surface level evaluation in which people are even likened to robots and automata”.

Somewhat frighteningly, by dehumanizing women people feel more free to be hostile towards them. “Research documents that stripping people of their humanity plays a role in legitimizing aggression”, the authors write.

The Jezebel blog has a more succinct take on the implications of this research for women. “The more we objectify women, judge them as other, and make them less human, the easier it is for all of us to tear them down and determine they’re not good enough”, they say.

Intelligence and beauty are not mutually exclusive, as celebrities such as actress Natalie Portman (Harvard psychology graduate) and model Lily Cole (arts student at Cambridge) aptly demonstrate.  What is most disconcerting about this study for me is how pervasive the tendency to judge a woman on her appearance is – regardless of gender or political inclination, participants focusing on looks rated the celebrities as less capable.  Underestimating women on the basis of their attractiveness allows society to shift away from being a meritocracy and does all women, conventionally attractive or not, a huge disservice.

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Financial altruism leads to depression

Lending moneyDo you give cash to people who aren’t your direct family or close friends, including people on the street begging for money? A new study in PLoS One suggests that such charitable behaviour will eventually lead to major depression.

Author Takeo Fujiwara found that financial altruism towards someone other than a family member or close friend was significantly associated with the onset of major depression two or three years later. Study participants who provided $10 a month or more to someone outside their close personal group were 2.6 times more likely to develop major depression than less generous individuals.

On the other hand, neither unpaid assistance – for example, helping someone other than family members or close friends with transportation or childcare – nor emotional support – comforting, listening to problems, or giving advice to anyone outside of your close personal circle – was associated with major depression.  In fact, providing unpaid assistance was nonsignificantly associated with protection against depression.

The author suggests that when people give money to others, they expect some sort of ethereal reward – such as reputation or status – in return for exhibiting good behaviours. People providing emotional support immediately and directly receive emotional reward, like a sense of meaning or purpose. This disparity in compensation for altruistic behaviour might explain why those providing emotional support did not develop of MD whereas those providing financial support did.

“The differential effect on major depression between unpaid assistance [and financial support] might be due to the difference of focus, whether outside the self or not”, says Dr Fujiwara. “[P]eople might join a volunteer activity from an achievement-oriented egocentricity, rather than focusing outside the self.”

In addition, people who give money to others might feel overstretched, as financial resources are harder to come by than emotional ones, and guilty when they don’t give, both of which might contribute to major depression.

A previous study, however, has shown that providing financial support to children or grand children protects against the later onset of major depression.  Better focus your financial generosity your close friends and family then.

Takeo Fujiwara (2009) Is Altruistic Behavior Associated with Major Depression Onset? PLoS ONE 4 (2) DOI: 10.1371/journal.pone.0004557

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Attitude has no effect on survival in women with breast cancer

Many patients with cancer feel that their attitude towards the ‘fight’ is an important part of beating the disease, but maintaining a positive perspective is pretty tough in the face of a life-threatening malignancy.

A large, population-based study published in the Journal of Clinical Oncology has now found that psychosocial factors such as fighting spirit and fatalism have no effect on survival in patients with breast cancer. The authors Phillips et al. emphasize that their results could allay the concerns of anxious women who believe that their mental attitude towards breast cancer will affect their likelihood of survival, and could in fact lift the burden of responsibility such women may feel.

Phillips et al. studied 708 Australian women diagnosed with nonmetastatic breast cancer before the age of 60 (average age 40 years old). At study entry approximately 11 months after diagnosis, all women completed an array of psychosocial tests that were designed to assess factors such as anxiety and depression, coping style, and social support. These women were then followed up for an average of 8.2 years.

In total, 33% of women experienced distant recurrence of their cancer and 24% died during follow-up. Once the patient data had been adjusted to take into account other factors that affect chances of recovery, such as tumour size, no associations could be found between psychosocial factors and either distant disease-free survival or overall survival.

The authors conclude that their study does not support the controversial theory that psychosocial factors influence survival after breast cancer. They state, “This should be reassuring for women, particularly those who experience substantial levels of psychosocial distress after their diagnosis.”

It is important to note, however, that therapies that aim to reduce psychosocial stress in women with breast cancer should not be discounted, as such interventions do seem to improve quality of life.

K.-A. Phillips, R. H. Osborne, G. G. Giles, G. S. Dite, C. Apicella, J. L. Hopper, R. L. Milne (2008). Psychosocial Factors and Survival of Young Women With Breast Cancer: A Population-Based Prospective Cohort Study. Journal of Clinical Oncology 26 (28): 4666-4671 DOI: 10.1200/JCO.2007.14.8718

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