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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.

Medical writing support, postnuclear disaster evacuation, and publication culture: Most read articles in February

10 Mar, 16 | by Emma Gray

Medical writing support and the quality of reporting, postnuclear disaster evacuation, and the current publication culture

File:Left-handed writing with wristwatch.jpg

Once again, this month sees a selection of new papers entering the Top 10 Most Read list, alongside some old favourites. Returning to the top spot this month is Teschke et al‘s paper on bicycling injury hospitalisation rates, which continues to attract attention and generate discussion via our eLetters section. Entering at number two is a cross-sectional study examining the associations between mortality and registered nurse staffing in English hospital trusts, complete with podcast and press release. Gaining a significant amount of attention on Twitter, Gattrell et al examine the relationship between medical writing support and the quality of reporting of the results of randomised controlled trials at number three, and at number eight Nomura et al write about the long-term impact of postnuclear disaster evacuation on diabetes, hyperlipidaemia and hypertension. Concluding the list at number ten, Tijdink et al investigate the biomedical scientist’s perception of the prevailing publication culture.

Rank Author(s) Title
1 Teschke et al. Bicycling injury hospitalisation rates in Canadian jurisdictions: analyses examining associations with helmet legislation and mode share
2 Griffiths et al. Registered nurse, healthcare support worker, medical staffing levels and mortality in English hospital trusts: a cross-sectional study
3 Gattrell et al. Professional medical writing support and the quality of randomised controlled trial reporting: a cross-sectional study
4 Steffens et al. Social group memberships in retirement are associated with reduced risk of premature death: evidence from a longitudinal cohort study
5 Pitman et al. Bereavement by suicide as a risk factor for suicide attempt: a cross-sectional national UK-wide study of 3432 young bereaved adults
6 Marsh et al. Cost-effectiveness analysis of arthroscopic surgery compared with non-operative management for osteoarthritis of the knee
7 Greenhalgh et al. Virtual online consultations: advantages and limitations (VOCAL) study
8 Nomura et al. Postnuclear disaster evacuation and chronic health in adults in Fukushima, Japan: a long-term retrospective analysis
9 Kristensen et al. The effect of statins on average survival in randomised trials, an analysis of end point postponement
10 Tijdink et al. How do scientists perceive the current publication culture? A qualitative focus group interview study among Dutch biomedical researchers

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

‘Ultra-processed’ foods make up more than half of all calories in US diet

9 Mar, 16 | by Emma Gray

…And contribute 90 per cent of all dietary added sugar intake

‘Ultra-processed’ foods make up more than half of all calories consumed in the US diet, and contribute nearly 90% of all added sugar intake, finds research published in the online journal BMJ Open.

Ultra-processed foods are formulations of several ingredients. Besides salt, sugar, oils and fats, they include substances not generally used in cooking, such as flavourings, emulsifiers, and other additives designed to mimic the qualities of ‘real foods’.

Ultra-processed foods include mass produced soft drinks; sweet or savoury packaged snacks; confectionery and desserts; packaged baked goods; chicken/fish nuggets and other reconstituted meat products; instant noodles and soups.

To assess the contribution of ultra-processed foods to the intake of added sugars in the US diet, the researchers drew on dietary data invoving more than 9000 people from the 2009-10 National Health and Nutrition Examination Survey (NHANES), an ongoing nationally representative cross sectional survey of US civilians.

They looked at the average dietary content of added sugars and the proportion of people who consumed more than 10% of their total energy intake—the maximum recommended limit—from this source.

Ultra-processed foods made up over half of total calorie intake (just under 60%) and contributed almost 90% of energy intake from added sugars.

Added sugars represented 1 in every 5 calories in the average ultra-processed food product—far higher than the calorie content of added sugars in processed foods and in unprocessed or minimally processed foods andprocessed culinary ingredients, including table sugar, combined.

A strong linear association emerged between the dietary content of ultra-processed foods and the overall dietary intake of added sugars.

Furthermore, the proportion of people exceeding the recommended upper limit of 10% of energy from added sugars was far higher when ultra-processed food consumption was high, rising to more than 80% among those who ate the most ultra-processed foods.

Notably, only those Americans whose ultra-processed food consumption was within the lowest 20% had an average daily added sugar intake that fell below the maximum recommended limit.

Several leading health bodies, including the World Health Organization, the Canadian Heart and Stroke Foundation, the American Heart Association, and the US Dietary Guidelines Advisory Committee have concluded that excess added sugar intake increases the risk not only of weight gain, but also of obesity and diabetes, which are associated with a heightened risk of cardiovascular disease, and tooth decay.

Cutting back on the consumption of ultra-processed foods could be an effective way of curbing excessive added sugar intake in the US, conclude the researchers.

#BMJOpen5years: 2015 article highlight

29 Feb, 16 | by aaldcroft

We’ve been celebrating our fifth anniversary by highlighting some of the articles that have gained us attention, along with some that demonstrate our unique approach. 

Our final highlight, from 2015, comes from Mari Hysing, from Uni Research Health, and colleagues. Sleep and use of electronic devices in adolescence: results from a large population-based study was our most downloaded article in 2015, and has an Altmetric score of 319. According to the database Scopus, the article has already been cited 7 times.

Using data from nearly 10,000 adolescents, the study shows an association between screen time and quality of sleep. The longer a teen spends looking at a screen throughout the day, the worse the quality of sleep he or she is likely to have.

screen use

We asked Dr Hysing about the impact the article has made. She replied:

Research is quite a lonely exercise and knowing that others are interested in what we do gave us extra  motivation to continue.   It has been a great experience to publish this paper and  it was a very intense and fascinating week when the article got published.   

I have never experienced this level of media interest–by far–and this is probably a once in a lifetime experience.  Newspapers, TV channels and radio interviews from all over the world took most of my time that week.  Being able to reach out to so many with the research we do is a great experience. This is what we work for. 

Our study was on  the association between use of electronic devices and sleep. And I realized how many really struggle to get the sleep that they need, and how hard it is to log off and prioritize sleep. In addition to the interest from adolescents and parents, it seemed to be a big problem among the journalist that did the interviews. Maybe this is one reason why our article gained so much media attention?

#BMJOpen5years: 2014 article highlight

26 Feb, 16 | by aaldcroft

This week we’re celebrating our fifth anniversary by highlighting some of the articles that have gained us attention, along with some that demonstrate our unique approach. 

Cited 49 times in Web of Science, and with an Altmetric score of 306, our 2014 article highlight investigates the relationship between salt intake, blood pressure, stroke, and ischaemic heart disease mortality.

Using data from more than 31,500 people, Feng He and colleagues show that salt intake decreased by 15% in England from 2003-2011. During the same period, heart disease and stroke deaths fell by around 40%.

While several factors are likely at play, the results are encouraging. However, with 70% of the English population still consuming more than the recommended quantity of salt (6 g/day)–much of it coming from processed foods–further efforts to reduce salt consumption are needed.


#BMJOpen5years: 2013 article highlights

25 Feb, 16 | by aaldcroft

This week we’re celebrating our fifth anniversary by highlighting some of the articles that have gained us attention, along with some that demonstrate our unique approach. 

For 2013, we’d like to present two articles along with some key statistics.

Do healthier foods and diet patterns cost more than less healthy options? A systematic review and meta-analysis

Conclusions: This meta-analysis provides the best evidence until today of price differences of healthier vs less healthy foods/diet patterns, highlighting the challenges and opportunities for reducing financial barriers to healthy eating.

Key statistics:

  • Cited 41 times in Web of Science
  • Over 55,000 total full text and PDF downloads
  • Altmetric score of 708


A school-based education programme to reduce salt intake in children and their families (School-EduSalt): protocol of a cluster randomised controlled trial

BMJ Open strongly believes in the importance of publishing study protocols. Published in 2013, this protocol from China presents the methods for a cluster randomised control trial where children receive an educational intervention to reduce salt intake. Children are then asked to bring the salt reduction message home to educate their families.

Results were published in 2015 in The BMJ.

#BMJOpen5years: 2012 article highlight

24 Feb, 16 | by aaldcroft

Hypnotics’ association with mortality

This week we’re celebrating our fifth anniversary by highlighting some of the articles that have gained us attention, along with some that demonstrate our unique approach. 

Cited 66 times in Web of Science and with an Altmetric score of 480, “Hypnotics’ association with mortality or cancer: a matched cohort study” is certainly one of the most influential papers ever published in BMJ Open. Using a database including more than 10,000 patients, the study from Daniel Kripke and colleagues highlighted an association between sleeping pills and mortality.


We wrote to Dr Kripke to comment on the impact his article has had around the world:

“Publishing in BMJ Open was very satisfying, since the review was fast and fair, editing done well, and publication rapid and accessible.  The press release was remarkably effective.  In 50 years of research, I have never had an article covered so widely:  not only in European and North American media, but also in Japan, China, Thailand, even Myanmar, Bali, Yemen, and Ruanda.

“The important result, four years later, is at least 50 new studies of hypnotics risks, most of which mention our work.  This growing scientific focus is confirming and defining the risks of hypnotics more clearly.  I was particularly happy with Weich et al. that largely replicated our results in an even better-done study of a larger group, and Palmaro et al. that clarified how short-term hypnotics exposures have particularly high risk ratios.  New British and Taiwan studies have expanded the evidence for severe infection risks of hypnotics, a phenomenon that requires much more clinical and laboratory exploration.”

Also of note is the extensive post-publication discussion, along with extensive mentioning on Twitter that continues four years later.

Dr Kripke notes,

“In BMJ Open, the lively COMMENTS section response was very helpful in clarifying scientific critiques of our work, some of which I had the opportunity to rebut, and in disclosing the public emotional reactions that we need to understand for public health interventions.”

#BMJOpen5years: 2011 article highlight

24 Feb, 16 | by aaldcroft

Uses and misuses of the STROBE statement


This week we’re celebrating our fifth anniversary by highlighting some of the articles that have gained us attention, along with some that demonstrate our unique approach. 

The use of reporting guidelines has always been central to BMJ Open, and we’re happy to see that one of the articles published in our very first edition, back in February 2011, is also one of our most highly cited.

Uses and misuses of the STROBE statement  has been cited more than 60 times in the Web of Science. By reviewing the literature, Bruno da Costa and colleagues highlight how correctly to use reporting guidelines and how the guidelines are often misused to assess methodological quality rather than the quality of the reporting.

So what might explain the misuse of the guidelines? According to da Costa et al.,

“The misuse of STROBE as a tool to assess methodological quality may be explained by the lack of validated and accepted tools for such assessments. As a consequence, authors who want to assess methodological quality of studies may turn to reporting guidelines.”

While the message is simple, it is also important, and we believe the article deserves its place as one of the journal’s highlights. It was also the first among many articles that we have published relating to medical publishing and peer review.

Five years old and growing

23 Feb, 16 | by aaldcroft

Five years ago today, BMJ Open appeared on the scene. Conceived as a general medical journal to provide authors a fast, transparent route to publication, BMJ Open could have developed in many different ways. Happily it has developed into a journal we’re proud of, and despite its broad scope, it has grown into a journal with a strong identity. Publishing 230 articles in our first year, our growth has been steady and consistent, and we have increased our global presence every year. In 2015 we published over 1,500 articles from 70 countries. We have carved out a niche in qualitative research and the publication of study protocols and articles less likely to be accepted in traditional medical journals. 

Number of accepted papers

Importantly, as exemplified in our use of open peer review and the publication of reviewers’ reports, we have embraced the notion that research should be open and transparent. Just as importantly, we have a strong belief in the importance of sound methodology, asking authors to state clearly, up front, the methodological strengths and limitations of their study. We believe objectivity takes precedence over novelty and require our authors to adhere to the standards of reporting promoted by the EQUATOR network. Through these guiding principles, we have become, in only five years, the world’s largest general medical journal.

Now seems a good time to reflect upon what we have achieved, and where we would like to go. To celebrate, over the next few days we will be highlighting on our blog articles that have gained significant attention, along with articles that demonstrate our unique approach.

But, of course, there is still much work to be done. Looking into the future, we hope to continue down the path we are on, growing and developing, particularly in parts of the world that have historically been underrepresented in the medical literature. Global initiatives, such as BMJ’s China portal, will become increasingly important to us. We also hope to continue our efforts to make data more available and accessible, the importance of which has recently been stressed with the public health emergency surrounding the Zika virus. While we have made strong efforts by fully integrating our system with Dryad, we have only scratched the surface.

Most of all we want to thank the authors, reviewers, and readers who have made it all possible. Please join us in celebrating our first five years!

Membership of social/community groups after retirement linked to longer life

16 Feb, 16 | by Fay Pearson

Membership of social groups, such as book clubs or church groups, after retirement is linked to a longer life, with the impact on health and wellbeing similar to that of regular exercise, suggests research published in the online journal BMJ Open.

The more groups an individual belongs to in the first few years after s/he stops working, the lower their risk of death, the findings show.

Retirement represents a major life change, with the evidence from large long-term studies suggesting that the health and wellbeing of a substantial number of retirees goes downhill after they stop formal work.

But some people adjust to this transition better than others. In a bid to assess the potential impact of social group memberships, the researchers tracked the health of 424 people for six years after they had retired.

They were compared with the same number of people, matched for age, sex, and health status, but who were still working.

All the participants were at least 50 years old, living in England, and taking part in the English Longitudinal Study of Ageing, which started in 2002-3.

Each participant was asked how many different organisations, clubs, or societies, s/he belonged to, and which ones. They were also asked to complete a validated scale to assess quality of life, and another, to assess subjective physical health.

The results showed that individuals whose quality of life was good before retirement were more likely to score highly on quality of life assessment after retirement.

But membership of social groups was also associated with quality of life. Compared with those still working, every group membership lost after retirement was associated with around a 10% drop in quality of life score six years later.

Some 28 (6.65%) of the retirees died in the first six years after stopping work. Unsurprisingly, the strongest predictor of death was age, with someone at the age of 55 running a 1% risk of dying compared with an 8% chance for someone aged 65.

Subjectively rated health was not a significant predictor of death, but the number of group memberships was.

If a person belonged to two groups before retirement, and kept these up over the following six years, their risk of death was 2%, rising to 5% if they gave up membership of one, and to 12% if they gave up membership of both.

No such patterns were seen for those still in formal employment.

The researchers separately assessed whether changes in physical activity levels affected risk of death and compared this with the magnitude of the effect of social group membership.

They found that if a person exercised vigorously once a week before retirement, and kept up this frequency afterwards, their chance of dying over the next six years was 3%, rising to 6% if they reduced the frequency to less than once a week, and to 11% if they stopped altogether.

Among those who were still working, the equivalent figures were 3%, 5%, and 8%.

“Accordingly, we can see that the effects of physical activity on health were comparable to those associated with maintaining old group memberships and developing new ones,” write the researchers.

This is an observational study so no firm conclusions can be drawn about cause and effect, but the findings have unique practical implications for retirement planning, say the researchers.

“They suggest that as much as practitioners may help retirees adjust by providing support with financial planning, they may also help by providing social planning,” they write.

“In this regard, practical interventions should focus on helping retirees to maintain their sense of purpose and belonging by assisting them to connect to groups and communities that are meaningful to them,” they conclude.

Higher nurse to patient ratio linked to reduced risk of inpatient death

9 Feb, 16 | by Emma Gray

Death rates 20 per cent lower in hospitals with 6 or fewer patients per registered nurse

A higher nurse to patient ratio is linked to a reduced risk of inpatient death, finds a study of staffing levels in NHS hospitals, published in the online journal BMJ Open.

In trusts where registered (professionally trained) nurses had six or fewer patients to care for, the death rate was 20 per cent lower than in those where they had more than 10.

Policies geared towards substituting registered nurses with healthcare support workers (healthcare assistants and nursing auxiliaries) should at the very least be reviewed, conclude the researchers

Previous research suggests that the nurse to patient ratio has some bearing on outcomes, but few studies have taken account of the impact of other members of medical staff.

They therefore included two measures over two years (2009-11) in their analysis: the number of beds per registered nurse, doctor, and healthcare support worker in 137 acute care trusts; and the number of patients per ward nurse, drawn from a survey of just under 3000 registered nurses in a nationally representative sample of 31 of these trusts (covering 46 hospitals and 401 wards).

They also calculated the predicted number of deaths for medical and surgical inpatients, taking account of influential factors, such as age, other underlying conditions, and number of emergency admissions during the previous 12 months.

The registered nurse headcount varied by as much as a factor of 4 between those at the top and bottom of the staffing scale. Even after taking account of all nursing staff, this variation only dropped to a threefold difference between those with the highest and lowest nurse headcounts.

Among patients admitted to medical wards, higher death rates were associated with higher numbers of occupied beds for each registered nurse and for each doctor employed by the trust.

By contrast, higher numbers of healthcare support workers were associated with higher rates of inpatient death.

When all staff groups were included in the statistical analysis of all 137 trusts, the associations remained significant only for doctors and healthcare support workers.

Among the subsidiary group of 31 trusts, death rates were 35.2/1000 medical admissions, out of a total of 1 260, 558, and 8.9/1000 surgical admissions, out of a total of 1 084 429.

But the death rate was 20% lower in those where each registered nurse cared for an average of six or fewer medical inpatients than in trusts were each registered nurse cared for 10 or more. These associations remained significant after further statistical analysis.

The results on surgical wards were similar, with higher registered nurse to patient ratios associated with a 17% lower inpatient death rate.

This is an observational study, so no firm conclusions can be drawn about cause and effect, added to which the findings on nurse to patient ratios are based on only 31 trusts.

“This [study] does not, in itself, provide a robust basis to identify safe staffing thresholds,” they say. “However, given the overall strength of evidence for an association, it does seem feasible to identify staffing levels where risk to patients is likely to be increased,” they suggest.

Economic pressures and the ageing profile of the nursing workforce internationally all point to a potential future with fewer registered nurses, they warn. But substituting them for less well trained staff may be unwise, they say.

“When determining the safety of nurse staffing on hospital wards, the level of registered nurse staffing is crucial, and there is no evidence to suggest that higher levels of healthcare support worker staffing have a role in reducing mortality rates,” they write.

“Current policies geared towards substituting [these] workers for registered nurses should be reviewed in the light of this evidence,” they conclude.

A podcast for this manuscript is available to listen to here: