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Welcome to the BMJ Open blog. BMJ Open is an open access journal, dedicated to publishing medical research from all disciplines and therapeutic areas.

Find out more about the journal here.

We will be updating the blog with news about the journal, highly accessed papers, press coverage, events and matters of interest in the open access and publishing world, and anything else that catches our eye.

Weekend screen time linked to poorer bone health in teen boys

10 Jun, 15 | by flee

Weekend screen time is linked to poorer teen bone health—but only in boys, reveals research published in BMJ Open.

The apparent lack of impact of leisure screen time on teen girls’ bone health may be explained by their different body fat distribution, suggest the researchers.

They base their findings on participants in the Tromsø Fit Futures Study in Norway, which involved 961 of the region’s 15-17 year old school pupils in 2010-11 (first wave) and 688 (66%) of this original group two years later in 2012-13 (second wave).

At both time periods, the teens were quizzed in detail about their lifestyles, including how much time they spent on their computers or watching TV/DVDs at the weekend and outside of school hours during the week; how much they smoked and drank; and what they ate, collected by food frequency questionnaires to gauge calcium and soft drink intake—factors known to affect bone mineral density.

They were also asked about their average weekly levels of physical activity in the preceding year, which was graded into sedentary; at least 4 hours walking, cycling or formal exercise; at least 4 hours of recreational sports; and hard training/competitive sport several times a week.

The bone mineral density was assessed at the hip, top of the thigh bone (femoral neck), and the whole skeleton, and their vitamin D level was measured from blood samples. Height and weight measurements (BMI) were also taken.

The analyses showed that boys spent more time in front of any screen than girls, averaging around 5 hours a day at the weekend and just under 4 hours during the week. The equivalent figures for girls were 4 hours at weekends and just over 3 hours during the week.

While more time spent in front of a screen at the weekend was linked to lower levels of physical activity, one in five girls and one in four boys, who whiled away more than 4 hours on Saturdays and Sundays on screen time, also said they clocked up more than 4 hours a week on hard training or competitive sports.

Lower bone mineral density was linked to weekend screen time, but was only significant among boys, among whom bone mineral density was lower at all the sites tested. Among girls, the positive association was only evident for the femoral neck.

After taking account of potentially influential factors, such as age, the degree of sexual maturity, and weekday screen time, the association strengthened for boys.

Two to 4, or more than 6 hours, in front of a screen were linked to statistically significant reductions of bone mineral density at the femoral neck compared with boys clocking up fewer than 2 hours of screen time daily at the weekend.

But boys who spent 4 to 6 hours in front of a screen tended to have higher than expected bone mineral density levels.

The opposite was true of girls among whom 4-6 hours of weekend screen time daily was associated with higher bone mineral density, even though they took less exercise than those who said they spent less time in front of a screen.

All these trends persisted when the assessments were repeated after two years.

“These conflicting results may be related to different factors, as the relationship between fat and bone varies with age and hormones,” say the researchers.

This is an observational study so no definitive conclusions can be drawn about cause and effect.

But the researchers conclude: “Our study suggests persisting associations of screen based sedentary activities on bone health in adolescence. This detrimental association should therefore be regarded as of public health importance.”

Dissemination bias, biguanide and clinician self-management: Most read articles in May

4 Jun, 15 | by flee

This month’s Top 10 Most Read includes a selection of new entries; including Meerpohl et al’s article on evidence-informed recommendations to reduce dissemination bias in clinical research. Mudge et al’s article on clinicians view on their role in self-management approaches and Anholm et al’s paper on the therapy of biguanide in patients with coronary artery disease and newly diagnosed type-2 diabetes were popular additions to this month’s most read articles.


Rank Author(s) Title
1 Anholm et al. Adding liraglutide to the backbone therapy of biguanide in patients with coronary artery disease and newly diagnosed type-2 diabetes (the AddHope2 study): a randomised controlled study protocol
2 Parand et al. The role of hospital managers in quality and patient safety: a systematic review
3 Branas et al. The impact of economic austerity and prosperity events on suicide in Greece: a 30-year interrupted time-series analysis
4 Smith et al. Why do smokers try to quit without medication or counselling? A qualitative study with ex-smokers
5 Meerpohl et al. Evidence-informed recommendations to reduce dissemination bias in clinical research: conclusions from the OPEN (Overcome failure to Publish nEgative fiNdings) project based on an international consensus meeting
6 Mudge et al. Who is in control? Clinicians view on their role in self-management approaches: a qualitative metasynthesis
7 Hysing et al. Sleep and use of electronic devices in adolescence: results from a large population-based study
8 Deane et al. Priority setting partnership to identify the top 10 research priorities for the management of Parkinson’s disease
9 Kato et al. Diagnosed diabetes and premature death among middle-aged Japanese: results from a large-scale population-based cohort study in Japan (JPHC study)
10 Hubble et al. Trunk muscle exercises as a means of improving postural stability in people with Parkinson’s disease: a protocol for a randomised controlled trial

Most read figures are based on pdf downloads and full text views. Abstract views are excluded.

Many UK patients with gonorrhoea prescribed outdated antibiotics

28 May, 15 | by flee

Many UK patients with gonorrhoea are being prescribed antibiotics that are no longer recommended for treating the infection by their family doctor (GP), reveals research published in BMJ Open.

This failure to keep abreast of national clinical guidance is of concern, given the global threat of antibiotic resistance, say the researchers.

They base their findings on an analysis of electronic health records entered anonymously into the Clinical Practice Research Datalink— a large database containing the health records of around 5.5 million patients registered with 680 general practices around the UK—as well as information from anonymous monitoring of sexually transmitted infections in England.

They looked particularly at how doctors in general practice had treated the two most commonly diagnosed bacterial sexually transmitted infections in England, Chlamydia and gonorrhoea, between 2000 and 2011.

GPs diagnosed an estimated 193,000 people with Chlamydia and nearly 17,000 with gonorrhoea during this period, accounting for between 9% and16% of all Chlamydia cases and between 6% and 9% of all gonorrhoea cases in England.

The number of diagnoses GPs made for Chlamydia rose substantially from 22.8/100,000 of the population in 2000 to 29.3/100,000 of the population in 2011. And the proportion of patients treated for this infection rose from around six in every 10 (60%) to almost eight out of 10 (78%).

Most (90%) were prescribed an antibiotic recommended in national clinical guidance. But this was not the case for gonorrhoea.

The number of diagnoses fluctuated between 3.2 to 2.4/100,000 of the population, while the proportion treated ranged between a third (just under 33%) and just over half (54%).

Despite being discontinued as a recommended treatment for the infection in 2005, ciprofloxacin continued to be prescribed. This antibiotic accounted for more than four out of 10 prescriptions (42%) in 2007, and one in five in 2011.

The bacterium that causes gonorrhoea, Neisseria gonorrhoeae, is adept at developing resistance to the antibiotics used to treat it, and the evidence from other research shows that over a third of gonorrhoea infections treated at sexual health clinics were resistant to ciprofloxacin, for example, while up to one in five cases may be resistant to penicillin.

The researchers conclude that GPs make an important contribution to the diagnosis and treatment of bacterial sexually transmitted infections, but while most patients with Chlamydia are treated appropriately, “significant numbers” of those infected with gonorrhoea are not.

“Treatment of infections with reduced susceptibility or resistance to the prescribed therapy may inadvertently facilitate onward transmission and risks infection complications,” they write.

“Antimicrobial resistance in gonorrhoea is a global problem and may become an issue for Chlamydia in future,” they warn. “Practitioners should be alert to the likelihood of revisions to national treatment guidelines and of treatment failure in their patients.”

Oldest old less likely to be investigated or aggressively treated after surgery

25 May, 15 | by flee

Patients aged 80 and above are significantly less likely to be investigated or aggressively treated after surgery than their younger counterparts, reveals a national audit of hospital deaths, published in BMJ Open.

This is despite the fact that the oldest old have higher rates of trauma and multiple underlying conditions on admission, say the Australian researchers.

Care in the oldest old may be less aggressive, or scaled down because the outcome is expected to be poor or treatment considered futile, they say. Perceived future quality of life issues may also be a factor.

The researchers assessed data from a national audit of deaths after surgical procedures in every specialty carried out between 2009 and 2012 in 111 public and 61 private hospitals across Australia. This included one in five private hospitals and virtually all public teaching hospitals (99%).

In all, nearly 20,000 surgical patients died in hospital. Around half of these deaths were excluded because of data issues or because they occurred in people classified as brain deaths, or in those younger than 17 or in those who had had no surgery.

Some 11,201 were included in the final analysis. This group was divided into three age bands: 17-64; 65-79; and those aged 80 and above.

The researchers looked at the relationship between age, preoperative factors, such as multiple underlying conditions or trauma, and eight indicators of postoperative care.

These indicators were: fluid balance problems; return to theatre; unplanned intensive care unit admission; treatment in an intensive care unit; clinical issues; postoperative complications; the presence of infection at death; and whether, with hindsight, the surgeon would have managed the patient differently.

The average age of those who died soon after a surgical procedure was 78, and just under 44% (4892) were aged 80 and above. Of those who died in hospital, most had been admitted as emergencies (83.4%). Nearly half (45%) had an incapacitating and life threatening disease on admission.

The oldest old had higher rates of admission as a result of trauma or other emergency than either of the two other age groups. But they were treated differently, receiving lower levels of aggressive and expensive treatment.

They had around half the rate of unplanned returns to theatre (11.2%) of those aged 65-79 (20.2%). They were also less likely to have unplanned admissions to intensive care (16.3% vs 24%) and less likely to be treated in intensive care (59.7% vs 76.7%).

On average, the most elderly spent fewer days in hospital than those aged between 65 and 79 (9 vs 11 days) but more than the youngest (8 days).  And they were less likely to have postoperative complications diagnosed and reported than 65-79 year olds.

Those aged between 65 and 79 also had a higher prevalence of cancer, which may have explained their higher rates of admission to intensive care, a move “that is often rationalised due to high operational costs whatever the age group,” they write.

Surgical care for older patients tends to be complex, because of functional, physiological, psychological, and social factors, which are likely to influence decisions about their hospital care, say the researchers.

None the less, they point out that the oldest old had the lowest rate of diagnosed postoperative complications of all the age groups, despite virtually all of them having multiple underlying conditions, which are usually associated with a higher risk of problems arising after surgery.

“Our data suggest that there may be a culture of less intensive investigation, monitoring and possible failure to intervene in the elderly group,” they say, adding that the costs of surgery may rise more slowly than expected if older people continue to be given less aggressive postoperative care.

Should we stop talking about ‘negative’ results?

22 May, 15 | by Richard Sands, Managing Editor


BMJ Open recently published the results of a major EU-funded project (OPEN) investigating the problem of dissemination bias. Also know as publication bias, this is the distortion of the evidence base caused by selective or non-reporting of results. The authors concluded:

‘Despite various recent examples of dissemination bias and several initiatives to reduce it, the problem of dissemination bias has not been resolved.’

Many journals, including BMJ Open, have peer review processes that don’t judge importance, novelty or impact, making publishing so-called negative studies easier.

Still, the perception remains that authors find it harder to publish these studies or remain reluctant to do so. If this is true, how important is the terminology we use? Would more ‘negative’ results be published if we called them something else?

The term ‘negative result’ is used widely.  The EU OPEN project used it (OPEN Stands for ‘Overcome failure to Publish nEgative findings’). It appears in journal titles, such as the Journal of Negative Results in Biomedicine. There’s a PLOS negative results collection. Professor Stephen Curry from Imperial College wrote about the importance of negative results for UK newspaper The Guardian.

BMJ Open encourages researchers to publish their studies, especially trials, regardless of results. It’s a premise of the AllTrials campaign, initiated by BMJ. In this spirit, we recently promoted this paper on Twitter. In it, Andrew Wilson and colleagues at the University of East Anglia report a randomised controlled study of maintenance sessions following pulmonary rehabilitation in patients with chronic obstructive pulmonary disease. They concluded “We do not recommend that our maintenance programme is adopted.”

To promote the paper and our willingness to consider this kind of study, we tweeted the paper with the comment that it was great that the authors were publishing their RCT ‘despite [a] negative result’.

The feedback from researchers was interesting. “Don’t talk about ‘negative results’ in trials” said Ruairidh Milne (@ruairidhm). “Best not to talk about ‘negative’ and ‘positive’ results in trials” said Shaun Treweek (@shauntreweek); “An important result rather than negative.” Andrew Cook (@ajcook) commented “I meet people who think trials which show now [sic] effect are a waste – calling them negative doesn’t help arguing how useful they are”.

All good points and we haven’t even covered that there are different types of ‘negative’ result (papers showing evidence of the absence of an effect or papers reporting an absence of evidence can both be labelled ‘negative’).

So – should we be thinking about what we call studies like these? Is the term ‘negative result’ just too… negative? Could it be influencing authors (or editors) unduly and if so what should we be calling these studies?

Increasing the value of health research, e-cigarettes and the role of hospital managers in patient safety: Most read articles in April

7 May, 15 | by flee

April’s Top 10 Most Read includes a selection of new entries; including a bibliometric analysis on increasing the value of health research in the WHO African Region by Uthman et al and an article on non-health decision-makers’ use of evidence on the social determinants of health written by McGill et al. Parand et al’s systematic review on the role of hospital managers in quality and patient safety has made it’s way back up to the top of the table.

Rank Author(s) Title
1 Parand et al. The role of hospital managers in quality and patient safety: a systematic review
2 Uthman et al. Increasing the value of health research in the WHO African Region beyond 2015—reflecting on the past, celebrating the present and building the future: a bibliometric analysis
3 Parsons et al. What the public knows and wants to know about medicines research and development: a survey of the general public in six European countries
4 Moore et al. Electronic-cigarette use among young people in Wales: evidence from two cross-sectional surveys
5 Deane et al. Priority setting partnership to identify the top 10 research priorities for the management of Parkinson’s disease
6 Hubble et al. Trunk muscle exercises as a means of improving postural stability in people with Parkinson’s disease: a protocol for a randomised controlled trial
7 Hysing et al. Sleep and use of electronic devices in adolescence: results from a large population-based study
8 Cripton et al. Severity of urban cycling injuries and the relationship with personal, trip, route and crash characteristics: analyses using four severity metrics
9 Rachiotis et al. What has happened to suicides during the Greek economic crisis? Findings from an ecological study of suicides and their determinants
10 McGill et al. Trading quality for relevance: non-health decision-makers’ use of evidence on the social determinants of health

Most read figures are based on pdf downloads and full text views. Abstract views are excluded.

UK doctors unlikely to be able to repay student loans

20 Apr, 15 | by Fay Pearson

UK doctors are unlikely to be able to repay their student loans over the course of their working lives, amassing debts of more than £80,000 by the time they graduate, in some cases, finds research published in the online journal BMJ Open.

What’s more, there are clear gender differences in the amount of cash required to service these debts, the analysis shows, with women paying more in interest, despite earning less than men.

The researchers base their findings on the average earnings of 4286 doctors working more than 30 hours a week, who had taken part in national Labour Force Surveys between 1997 and 2014.

Annual tuition fees amount to £9000 for English students attending UK universities, and most medical degrees take five years to complete.

Since 2012, students have been able to borrow the annual fees and get a maintenance loan to cover living costs from the Student Loan Company.

Repayments are charged at an annual interest rate of 3% plus annual inflation rate (Retail Price Index) and based on 9% of salary earned above £21,000 gross income. Debts are automatically written off after 30 years, irrespective of the sums outstanding.

A medical student graduating in 2014 would have clocked up a debt of £40,000 for tuition fees.
If maintenance loans are factored in, this would add £24,000 for a student living at home; an additional £30,000 for a student living away from home; and £42,000 for a student living away from home in London, amounting to a total of between £64,000 and £82,000 by the time of graduation.

The survey responses showed that average full time salaries rose with age, but then gradually fell after the age of 55, with a wide gap in earnings starting to emerge between men and women from the age of 30 onwards.

At the age of 55, male doctors earned 35% more than their female colleagues, which was mainly attributable to hourly wage rates rather than the number of hours worked.

The researchers used the average age-salary profiles, projected future repayments, and cumulative debt levels to calculate the total sums required to service the loans.

For those borrowing against tuition fees alone, full time male doctors would have to stump up £57,303 to clear their debts over 20 years, while their female colleagues would need to find just short of £62,000 over a period of 26 years.

When maintenance loans were factored in, the researchers calculated that the total sums to be repaid added up to £75,786 for an initial debt above £46,000 for women doctors and £110,644 for an initial debt above £65,145 for their male colleagues.

For initial debts below £50,000, women repay more, despite earning less, because their debt lasts longer and accrues more interest. But for initial debts above £50,000, men repay more because their average yearly salaries are higher.

The researchers point out for those able to repay their loans within the 30 year timeframe, a higher yearly salary is advantageous because an early repayment means less interest. But for those unable to pay off their loans, a lower salary is advantageous, because it means lower yearly repayments and the writing off of the residual debt.

“It seems reasonable that these repayment variations may actually exist across many graduate careers in the UK,” write the researchers. “It is also apparent that at the current level of fees, even small changes in the student loan contract will have substantial implications for lifetime wealth across different income groups, across male and female graduates, and on the sustainability of the student loans system.”

Many teens try e-cigarettes, but few become regular users

15 Apr, 15 | by Fay Pearson

E-cigarettes are popular with teens, including those who have never smoked, but few of those who try them become regular users, while most of those who do so are also smokers, finds research published in the online journal BMJ Open.

The researchers base their findings on the results of two nationally representative surveys of primary and secondary schoolchildren (CHETS Wales 2 and the Welsh Health Behaviour in School aged Children) from more than 150 schools in Wales carried out in 2013 and 2014.

In all, 1601 children aged 10-11 and 9055 11-16 year olds were quizzed about their use of e-cigarettes.

Use of e-cigarettes at least once was more common than having smoked a conventional cigarette among all age groups, except the oldest (15-16 year olds).

Some 5.8% of 10-11 year olds had tried e-cigarettes—far more than had tried tobacco (1.6%)—while a sizeable proportion (12.3%) of 11-16 year olds said they had used e-cigarettes, irrespective of gender, ethnic background, or family affluence.

This contrasts with the patterning seen in smoking, where all these factors come into play, suggesting that e-cigarettes may have wider appeal among all sectors of the teen population, say the researchers.

Similarly, the proportion of teens who had used e-cigarettes, but who had never smoked, rose from 5.3% among 10-11 year olds, to 8% among 15-16 year olds.

But only 1.5% (125) of those aged 11-16 said they used e-cigarettes regularly—defined as at least once a month. This included 0.3% of those who claimed they had never smoked conventional cigarettes.

These figures suggest that “e-cigarettes are unlikely to make a major direct contribution to adolescent nicotine addiction at present,” write the researchers, who point out that the World Health Organization has recognised that there is little evidence on whether e-cigarettes may or may not act as a gateway to conventional smoking.

The odds of regular e-cigarette use were 100 times higher among current weekly smokers than among non-smokers, and 50 times higher among those who had smoked cannabis

The strong link between current smoking and e-cigarette use suggests that teens are not using these products to help them quit smoking, say the researchers.

They admit that a lack of consensus about what constitutes ‘use’ of an e-cigarette presents something of a challenge for research in this area, and suggest that further much longer term studies to include the generation of young people who have grown up with e-cigarettes are needed before firmer conclusions can be drawn.

UK research cash for dementia and stroke still way too low

14 Apr, 15 | by flee

The amount of government money pumped into dementia and stroke research in the UK has risen significantly in recent years, but it is still way too low when compared with the economic and personal impact these conditions have, finds a study published in BMJ Open.

The researchers assessed central government and charity research expenditure in 2012 into the UK’s leading causes of death and disability: cancer, coronary heart disease, dementia and stroke.

In 2012, all four conditions accounted for over half (55%) of all UK deaths and for 5.5 million disability adjusted life years (DALYs), which combine the number of years of life lost to early death, ill health, or disability.

The amount of funding was compared with the population impact of the individual conditions: prevalence, the number of years lost to early death, ill health, or disability, and the total health and social care costs.

The combined amount of research funding allocated by the government and charities to all four conditions came to £856 million in 2012, almost two thirds of which (64%; £544 million) was allocated to cancer.

Around one fifth (19%; £166 million) was devoted to coronary heart disease, while just 11% (£90 million) was allocated to dementia and even less (7%; £56 million) to stroke research.

That same year, there were around 2.3 million cases of cancer, the same number of coronary heart disease cases, 0.8 million cases of dementia and 1.2 million of stroke.

In 2012 a total of 2.9 million DALYs were lost to cancer, 1.5 million to coronary heart disease, 0.4 million to dementia and 0.7 million to stroke.

The costs of healthcare were highest for cancer (£4.4 billion) and lowest for dementia at £1.4 billion and for stroke at £1.8 billion.

But the social care costs of dementia outweighed the social care costs of the other three conditions combined. And the combined costs of health and social care for dementia came to £11.6 billion in 2012, the researchers calculated.

This was more than double the equivalent costs for cancer at £5 billion, and significantly more than for stroke (£2.9 billion) and coronary heart disease (£2.5 billion).

This means that for every £10 of health and social care costs attributable to each condition, £1.08 in research funding was spent on cancer, £0.65 on coronary heart disease, £0.19 on stroke, and just £0.08 on dementia, the researchers calculated.

Since 2010, there have been substantial changes in medical research funding policies, particularly by government organisations, which pumped 21% of the total share into dementia research and 12% into stroke research in 2012, with cancer attracting 46% of the total spend.

The equivalent figures in 2008 were 66% for cancer, 21% for coronary heart disease, 9% for dementia, and just 4% for stroke.

But the sums allocated by charities have scarcely budged since 2008, say the researchers. Charities are reliant on public funds so this stasis may be down to public perception of risk or a form of ageism, derived from the belief that stroke and dementia are inevitable only in the elderly, they suggest.

Despite the shift in funding priorities, research into the treatment and prevention of dementia and stroke remains underfunded when compared with the economic and personal impact these conditions have, they conclude.

Children with type 1 diabetes almost 5 times as likely to be admitted to hospital

13 Apr, 15 | by Fay Pearson

Children with type 1 diabetes run almost five times the risk of being admitted to hospital for any reason as their peers, finds research published in the online journal BMJ Open.

Pre-schoolers and those from disadvantaged backgrounds are most at risk, the findings indicate.

The number of new cases of childhood type 1 diabetes has been rising steadily by around 3-4% a year, the evidence shows, and the risk of death among those with the condition under the age of 30 is nine times that of the general public.

The researchers analysed the causes of hospital admission after a diagnosis of type 1 diabetes among 1577 Welsh children up to the age of 15.

All these children had been diagnosed with type 1 diabetes between 1999 and 2009, and their details entered into the Brecon Group Register—a network of healthcare professionals caring for children and young people with diabetes normally resident in Wales.

Around one in five children had been diagnosed with type 1 diabetes before the age of 5; two in five had been diagnosed after the age of 10.

Their hospital records were compared with those of 7800 children admitted to hospital up to May 2012, who had been randomly selected from the Patient Episode Database for Wales (PEDW), and matched for birth date, sex, and residential area.

The results showed that children with type 1 diabetes were almost five times as likely to be admitted to hospital for any cause as their peers.

Pre-schoolers were at highest risk of admission. After the age of 5 the risk fell by more than 15% for every five year rise in age at diagnosis.

Although there was no gender difference in risk, coming from a disadvantaged background was associated with an increased risk of hospital admission.

And those whose outpatient care was delivered at large centres were 16% less likely to be admitted to hospital as those treated in small centres. Most (78%) of those treated at large centres lived in urban areas.

“It is unsurprising that complications of suboptimal management, such as hypoglycaemia [low blood sugar] and ketoacidosis [excess sugar and acid in the blood] occur, leading to hospitalisation,” write the researchers.

But the personal costs to the individual and their families, and the financial toll on the NHS are considerable, they say.

They add: “This is an area of great clinical importance as patients admitted to hospital with diabetes aged under 30 years have a death rate nine times that of the general population.”