Mar. 27, 2013 ? Mathematical models can be used to study the spread of technological innovations among individuals connected to each other by a network of peer-to-peer influences, such as in a physical community or neighborhood. One such model was introduced in a paper published yesterday in the SIAM Journal on Applied Dynamical Systems.
Authors N. J. McCullen, A. M. Rucklidge, C. S. E. Bale, T. J. Foxon, and W. F. Gale focus on one main application: The adoption of energy-efficient technologies in a population, and consequently, a means to control energy consumption. By using a network model for adoption of energy technologies and behaviors, the model helps evaluate the potential for using networks in a physical community to shape energy policy.
The decision or motivation to adopt an energy-efficient technology is based on several factors, such as individual preferences, adoption by the individual's social circle, and current societal trends. Since innovation is often not directly visible to peers in a network, social interaction -- which communicates the benefits of an innovation -- plays an important role. Even though the properties of interpersonal networks are not accurately known and tend to change, mathematical models can provide insights into how certain triggers can affect a population's likelihood of embracing new technologies. The influence of social networks on behavior is well recognized in the literature outside of the energy policy domain: network intervention can be seen to accelerate behavior change.
"Our model builds on previous threshold diffusion models by incorporating sociologically realistic factors, yet remains simple enough for mathematical insights to be developed," says author Alastair Rucklidge. "For some classes of networks, we are able to quantify what strength of social network influence is necessary for a technology to be adopted across the network."
The model consists of a system of individuals (or households) who are represented as nodes in a network. The interactions that link these individuals -- represented by the edges of the network -- can determine probability or strength of social connections. In the paper, all influences are taken to be symmetric and of equal weight. Each node is assigned a current state, indicating whether or not the individual has adopted the innovation. The model equations describe the evolution of these states over time.
Households or individuals are modeled as decision makers connected by the network, for whom the uptake of technologies is influenced by two factors: the perceived usefulness (or utility) of the innovation to the individual, including subjective judgments, as well as barriers to adoption, such as cost. The total perceived utility is derived from a combination of personal and social benefits. Personal benefit is the perceived intrinsic benefit for the individual from the product. Social benefit depends on both the influence from an individual's peer group and influence from society, which could be triggered by the need to fit in. The individual adopts the innovation when the total perceived utility outweighs the barriers to adoption.
When the effect of each individual node is analyzed along with its influence over the entire network, the expected level of adoption is seen to depend on the number of initial adopters and the structure and properties of the network. Two factors in particular emerge as important to successful spread of the innovation: The number of connections of nodes with their neighbors, and the presence of a high degree of common connections in the network.
This study makes it possible to assess the variables that can increase the chances for success of an innovation in the real world. From a marketing standpoint, strategies could be designed to enhance the perceived utility of a product or item to consumers by modifying one or more of these factors. By varying different parameters, a government could help figure out the effect of different intervention strategies to expedite uptake of energy-efficient products, thus helping shape energy policy.
"We can use this model to explore interventions that a local authority could take to increase adoption of energy-efficiency technologies in the domestic sector, for example by running recommend-a-friend schemes, or giving money-off vouchers," author Catherine Bale explains. "The model enables us to assess the likely success of various schemes that harness both the householders' trust in local authorities and peer influence in the adoption process. At a time when local authorities are extremely resource-constrained, tools to identify the interventions that will provide the biggest impact in terms of reducing household energy bills and carbon emissions could be of immense value to cities, councils and communities."
One of the motivations behind the study -- modeling the effect of social networks in the adoption of energy technologies -- was to help reduce energy consumption by cities, which utilize over two-thirds of the world's energy, releasing more than 70% of global CO2 emissions. Local authorities can indirectly influence the provision and use of energy in urban areas, and hence help residents and businesses reduce energy demand through the services they deliver. "Decision-making tools are needed to support local authorities in achieving their potential contribution to national and international energy and climate change targets," says author William Gale.
Higher quantities of social data can help in making more accurate observations through such models. As author Nick McCullen notes,"To further refine these types of models, and make the results reliable enough to be used to guide the decisions of policy-makers, we need high quality data. Particularly, data on the social interactions between individuals communicating about energy innovations is needed, as well as the balance of factors affecting their decision to adopt."
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The above story is reprinted from materials provided by Society for Industrial and Applied Mathematics.
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Journal Reference:
N. J. McCullen, A. M. Rucklidge, C. S. E. Bale, T. J. Foxon, W. F. Gale. Multiparameter Models of Innovation Diffusion on Complex Networks. SIAM Journal on Applied Dynamical Systems, 2013; 12 (1): 515 DOI: 10.1137/120885371
Note: If no author is given, the source is cited instead.
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Contact: Aileen Sheehy press.office@sanger.ac.uk 0044-012-234-96928 Wellcome Trust Sanger Institute
DNA sequencing reveals evidence for Mycobacterium abscessus transmission between Cystic Fibrosis patients
Researchers at Papworth Hospital, the University of Cambridge and the Wellcome Trust Sanger Institute have discovered why a new type of dangerous bacterial infection has become more common among people with Cystic Fibrosis around the world.
Through their ground-breaking research, the team has developed new measures to protect Cystic Fibrosis patients.
People with Cystic Fibrosis are prone to serious infection in part because they have sticky mucus that can clog up their lungs. In recent years doctors have seen a global increase in the number of infections caused by the antibiotic-resistant bacterial species Mycobacterium abscessus (M. abscessus). M. abscessus is distantly related to the bacterium that causes Tuberculosis and is usually found in water and soil. Until now, experts had thought it could not be passed from person to person.
"There has been worldwide concern about the rising number of M. abscessus infections in people with Cystic Fibrosis and anxiety that spread from person to person might be responsible," said Dr Andres Floto, Research Director of the Cystic Fibrosis Unit at Papworth Hospital, Principal Investigator at the Cambridge Institute for Medical Research, University of Cambridge and lead author of the research published in The Lancet. "Our work has allowed us to lead the world in changing hospital infection control: we used state-of-the-art DNA sequencing technology to understand how the infection is being spread, which conventional techniques would have missed."
"Our results will help to protect patients from this serious infection."
The team used the latest methods to sequence the genomes of almost 170 isolates of M. abscessus from Cystic Fibrosis patients collected over a five-year period. By looking at the fine detail of the relationships between the bacterial genomes, to produce a 'family tree', the research team could determine where it was likely that infection had passed from one patient to another. They showed that, even with nationally recommended infection control measures in place, M. abscessus can spread between patients.
"We are increasingly able to use DNA studies to improve patient care," says Professor Julian Parkhill, Head of Pathogen Genomics at the Wellcome trust Sanger Institute. "By sequencing the complete genomes of bacteria we can accurately describe where they have emerged from and how they pass from person to person.
"This knowledge means that the clinical teams can develop new health measures to safeguard their patients. Our aim is to develop the best methods to detect and control infection."
This new information has led to rapid changes in how people with Cystic Fibrosis are cared for in hospital to protect them from this emerging threat.
###
For further information please contact:
Kate Lancaster, Papworth Hospital
Tel +44 (0)1480 364148
Mobile +44 (0) 07850 918627
Email Kate.lancaster@papworth.nhs.uk
Don Powell, Media Manager, Wellcome Trust Sanger Institute
Hinxton, Cambridge, CB10 1SA, UK
Tel +44 (0)1223 496 928
Mobile +44 (0)7753 7753 97
Email press.office@sanger.ac.uk
Publication details
Josephine M. Bryant, Dorothy M. Grogono, Daniel Greaves, Juliet Foweraker, Iain
Roddick, Thomas Inns, Mark Reacher, Charles S. Haworth, Martin D. Curran, Simon R. Harris1, Sharon J. Peacock, Julian Parkhill1and R. Andres Floto. (2013) 'Evidence for transmission of Mycobacterium abscessus between Cystic Fibrosis patients from whole-genome sequencing.
Published in the Lancet online 29 March 2013. doi: 10.1016/S0140-6736(13)60632-7,
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(13)60632-7/abstract
Funding
This work was supported by The Wellcome Trust, Papworth Hospital, NIHR Cambridge Biomedical Research Centre, The UK Health Protection Agency, Medical Research Council, and the UKCRC Translational Infection Research Initiative.
Participating centres
1. Wellcome Trust Sanger Institute, Hinxton, UK
2. Cambridge Institute for Medical Research, University of Cambridge, UK
3. Cambridge Centre for Lung Infection, Papworth Hospital, Cambridge, UK
4. Department of Medicine, University of Cambridge, UK
5. Health Protection Agency, Addenbrooke's Hospital, Cambridge, UK
6. HPA Health Protection Agency East of England Regional Epidemiology Unit, UK
7. HPA, Norfolk, Suffolk & Cambridgeshire Health Protection Unit, UK
8. Field Epidemiology Training Programme (FETP), Health Protection Agency, London, UK
The mission of the University of Cambridge is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence. It admits the very best and brightest students, regardless of background, and offers one of the UK's most generous bursary schemes. The University of Cambridge's reputation for excellence is known internationally and reflects the scholastic achievements of its academics and students, as well as the world-class original research carried out by its staff. Some of the most significant scientific breakthroughs occurred at the University, including the splitting of the atom, invention of the jet engine and the discoveries of stem cells, plate tectonics, pulsars and the structure of DNA. From Isaac Newton to Stephen Hawking, the University has nurtured some of history's greatest minds and has produced more Nobel Prize winners than any other UK institution with over 80 laureates.
http://www.cam.ac.uk
The Wellcome Trust Sanger Institute is one of the world's leading genome centres. Through its ability to conduct research at scale, it is able to engage in bold and long-term exploratory projects that are designed to influence and empower medical science globally. Institute research findings, generated through its own research programmes and through its leading role in international consortia, are being used to develop new diagnostics and treatments for human disease.
http://www.sanger.ac.uk
The Wellcome Trust is a global charitable foundation dedicated to achieving extraordinary improvements in human and animal health. We support the brightest minds in biomedical research and the medical humanities. Our breadth of support includes public engagement, education and the application of research to improve health. We are independent of both political and commercial interests.
http://www.wellcome.ac.uk
Papworth Hospital is an international centre of excellence for the treatment of heart and lung disease. Since carrying out the UK's first successful heart transplant in 1979, Papworth has established a reputation for leading edge research and innovation in cardiopulmonary medicine and surgery. As part of the Cambridge Centre for Lung Infection (CCLI), the Adult Cystic Fibrosis Centre at Papworth Hospital was established in 1994 and now looks after over 280 adults with CF from throughout the Eastern Region. The service is supported by a multidisciplinary team including: four CF specialist consultants, three CF specialist nurses, a dedicated team of ward nurses, research nurses, specialist physiotherapists, dieticians, pharmacists, social workers, psychologist, psychiatrist, secretaries and managers. Research within the CCLI has focused on understanding how bacteria, particularly nontuberculous mycobacteria (NTM) cause infection and inflammatory lung damage.
http://www.papworthhospital.nhs.uk/ccli.
[ | E-mail | Share ]
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AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Contact: Aileen Sheehy press.office@sanger.ac.uk 0044-012-234-96928 Wellcome Trust Sanger Institute
DNA sequencing reveals evidence for Mycobacterium abscessus transmission between Cystic Fibrosis patients
Researchers at Papworth Hospital, the University of Cambridge and the Wellcome Trust Sanger Institute have discovered why a new type of dangerous bacterial infection has become more common among people with Cystic Fibrosis around the world.
Through their ground-breaking research, the team has developed new measures to protect Cystic Fibrosis patients.
People with Cystic Fibrosis are prone to serious infection in part because they have sticky mucus that can clog up their lungs. In recent years doctors have seen a global increase in the number of infections caused by the antibiotic-resistant bacterial species Mycobacterium abscessus (M. abscessus). M. abscessus is distantly related to the bacterium that causes Tuberculosis and is usually found in water and soil. Until now, experts had thought it could not be passed from person to person.
"There has been worldwide concern about the rising number of M. abscessus infections in people with Cystic Fibrosis and anxiety that spread from person to person might be responsible," said Dr Andres Floto, Research Director of the Cystic Fibrosis Unit at Papworth Hospital, Principal Investigator at the Cambridge Institute for Medical Research, University of Cambridge and lead author of the research published in The Lancet. "Our work has allowed us to lead the world in changing hospital infection control: we used state-of-the-art DNA sequencing technology to understand how the infection is being spread, which conventional techniques would have missed."
"Our results will help to protect patients from this serious infection."
The team used the latest methods to sequence the genomes of almost 170 isolates of M. abscessus from Cystic Fibrosis patients collected over a five-year period. By looking at the fine detail of the relationships between the bacterial genomes, to produce a 'family tree', the research team could determine where it was likely that infection had passed from one patient to another. They showed that, even with nationally recommended infection control measures in place, M. abscessus can spread between patients.
"We are increasingly able to use DNA studies to improve patient care," says Professor Julian Parkhill, Head of Pathogen Genomics at the Wellcome trust Sanger Institute. "By sequencing the complete genomes of bacteria we can accurately describe where they have emerged from and how they pass from person to person.
"This knowledge means that the clinical teams can develop new health measures to safeguard their patients. Our aim is to develop the best methods to detect and control infection."
This new information has led to rapid changes in how people with Cystic Fibrosis are cared for in hospital to protect them from this emerging threat.
###
For further information please contact:
Kate Lancaster, Papworth Hospital
Tel +44 (0)1480 364148
Mobile +44 (0) 07850 918627
Email Kate.lancaster@papworth.nhs.uk
Don Powell, Media Manager, Wellcome Trust Sanger Institute
Hinxton, Cambridge, CB10 1SA, UK
Tel +44 (0)1223 496 928
Mobile +44 (0)7753 7753 97
Email press.office@sanger.ac.uk
Publication details
Josephine M. Bryant, Dorothy M. Grogono, Daniel Greaves, Juliet Foweraker, Iain
Roddick, Thomas Inns, Mark Reacher, Charles S. Haworth, Martin D. Curran, Simon R. Harris1, Sharon J. Peacock, Julian Parkhill1and R. Andres Floto. (2013) 'Evidence for transmission of Mycobacterium abscessus between Cystic Fibrosis patients from whole-genome sequencing.
Published in the Lancet online 29 March 2013. doi: 10.1016/S0140-6736(13)60632-7,
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(13)60632-7/abstract
Funding
This work was supported by The Wellcome Trust, Papworth Hospital, NIHR Cambridge Biomedical Research Centre, The UK Health Protection Agency, Medical Research Council, and the UKCRC Translational Infection Research Initiative.
Participating centres
1. Wellcome Trust Sanger Institute, Hinxton, UK
2. Cambridge Institute for Medical Research, University of Cambridge, UK
3. Cambridge Centre for Lung Infection, Papworth Hospital, Cambridge, UK
4. Department of Medicine, University of Cambridge, UK
5. Health Protection Agency, Addenbrooke's Hospital, Cambridge, UK
6. HPA Health Protection Agency East of England Regional Epidemiology Unit, UK
7. HPA, Norfolk, Suffolk & Cambridgeshire Health Protection Unit, UK
8. Field Epidemiology Training Programme (FETP), Health Protection Agency, London, UK
The mission of the University of Cambridge is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence. It admits the very best and brightest students, regardless of background, and offers one of the UK's most generous bursary schemes. The University of Cambridge's reputation for excellence is known internationally and reflects the scholastic achievements of its academics and students, as well as the world-class original research carried out by its staff. Some of the most significant scientific breakthroughs occurred at the University, including the splitting of the atom, invention of the jet engine and the discoveries of stem cells, plate tectonics, pulsars and the structure of DNA. From Isaac Newton to Stephen Hawking, the University has nurtured some of history's greatest minds and has produced more Nobel Prize winners than any other UK institution with over 80 laureates.
http://www.cam.ac.uk
The Wellcome Trust Sanger Institute is one of the world's leading genome centres. Through its ability to conduct research at scale, it is able to engage in bold and long-term exploratory projects that are designed to influence and empower medical science globally. Institute research findings, generated through its own research programmes and through its leading role in international consortia, are being used to develop new diagnostics and treatments for human disease.
http://www.sanger.ac.uk
The Wellcome Trust is a global charitable foundation dedicated to achieving extraordinary improvements in human and animal health. We support the brightest minds in biomedical research and the medical humanities. Our breadth of support includes public engagement, education and the application of research to improve health. We are independent of both political and commercial interests.
http://www.wellcome.ac.uk
Papworth Hospital is an international centre of excellence for the treatment of heart and lung disease. Since carrying out the UK's first successful heart transplant in 1979, Papworth has established a reputation for leading edge research and innovation in cardiopulmonary medicine and surgery. As part of the Cambridge Centre for Lung Infection (CCLI), the Adult Cystic Fibrosis Centre at Papworth Hospital was established in 1994 and now looks after over 280 adults with CF from throughout the Eastern Region. The service is supported by a multidisciplinary team including: four CF specialist consultants, three CF specialist nurses, a dedicated team of ward nurses, research nurses, specialist physiotherapists, dieticians, pharmacists, social workers, psychologist, psychiatrist, secretaries and managers. Research within the CCLI has focused on understanding how bacteria, particularly nontuberculous mycobacteria (NTM) cause infection and inflammatory lung damage.
http://www.papworthhospital.nhs.uk/ccli.
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Sasha and Malia Obama at the Inaugural parade (AP/Gerald Herbert)
While speaking on a radio program, Rep. Steve King (R-IA) criticized Sasha and Malia Obama for taking a vacation while the federal government is being squeezed by the so-called sequester -- the deep automatic spending cuts that went into effect earlier this month when Congress and President Obama failed to reach a budget agreement.
ThinkProgress, a progressive blog, reports that King was speaking on the Mickelson in the Morning program. A listener named Carla called in to discuss the sequester's effects on her son, a Marine. She complained that Michelle Obama was vacationing in the Bahamas with her two daughters while others are being squeezed by the government cuts.
"It's hard to stomach. When we're tightening our belts, we should either all do it or none of us do it," she said.
Earlier this week, conservative news outlet Breitbart.com reported that the girls were on spring break and named the resort where they were staying.
King agreed with the caller, saying, "Carla, you're on point and on the mark all the way through." King then went on to mention that the girls vacationed in Mexico the year before.
"He sent the daughters to spring break in Mexico a year ago," King said, referring to President Obama. "That was at our expense, too. And now to the Bahamas at one of the most expensive places there. That is the wrong image to be coming out of the White House."
The Obamas pay for family vacations themselves. However critics complain that those costs do not include security measures.
King, who is mulling a Senate bid in 2014, has been an outspoken critic of President Obama for years. During the 2008 presidential campaign, King predicted that should Obama beat John McCain, "then the radical Islamists, the al-Qaida, the radical Islamists and their supporters, will be dancing in the streets in greater numbers than they did on September 11."
This isn't quite the BlackBerry earnings story you're waiting for -- after all, the US figures covering the success (or otherwise) of the Z10 won't arrive until the next quarter. Instead, we're looking at the company's results from the end of the fiscal year to March 2nd, which shows that the smartphone maker made $94 million in GAAP income on revenues of $2.7 billion -- in contrast with the $125 million net loss it made in the same quarter last year. More importantly, however, it shipped out almost one million BlackBerry 10 devices during the three weeks of the quarter that they were available. In addition, it managed to push five million of its older smartphones and 370,000 PlayBook tablets out of the door, but saw user numbers fall from 79 million last quarter to 76 million now.
As revenue has remained relatively flat, the surge in profits can only be attributed to Thorstein Heins' aggressive cost-cutting measures, with the CEO remarking that the "numerous changes" he has implemented at the company have "resulted in [BlackBerry] returning to profitability." At the same time, Mike Lazaridis has announced that he'll retire from his position as vice-chair and director of the outfit he founded the better part of three decades ago. He'll exit the business on May 1st so that he can concentrate on his new enterprise, Quantum Valley Investments.
Update: During the conference call, Thorsten Heins has revealed that around two-thirds or three-quarters of the one million BB10 devices shipped have been sold.
As Secretary of State John Kerry met with President Hamid Karzai and oversaw the symbolic handoff of a major military prison on a surprise visit to Afghanistan this week, a suicide bombing killed five police officers in the eastern city of Jalalabad Tuesday.
The Taliban quickly claimed responsibility for today?s attack, which also injured at least five Afghans at the police headquarters in the provincial capital, according to the Associated Press. In a separate incident today a car bomb blast injured at least 10 British troops on a patrol base in Helmand Province, according to the Guardian.
The timing of the violence highlights the major security challenges that remain as the United States attempts to wind down a decade of intensive military presence in the country and hand control to the Afghans.
RECOMMENDED: How well do you know Afghanistan? Take our quiz.
The attacks came just hours after Secretary Kerry and President Karzai held a rosy news conference in Kabul on the state of US-Afghan relations, which have undergone particular strain in recent weeks after Karzai accused the US of working with the Taliban to deliberately keep the country weak.
(For more on the costs of the US war effort, read about the $610 million late fee Washington is currently paying on shipping containers it rented to ship home military equipment.)
But during his trip, Kerry was glowing in his appraisal of Karzai, declaring that he and the president were ?on the same page? when it came to Afghan security and reconciliation.
"I am confident the president [Karzai] does not believe the US has any interest except to see the Taliban come to the table to make peace and that we are completely cooperative with the government of Afghanistan with respect to the protection of their efforts and their people," Kerry told reporters.
Monday?s meeting was a pivot from the prickly interaction between Karzai and Defense Secretary Chuck Hagel on Mr. Hagel?s own trip to the country earlier this month. During that visit, Hagel and Karzai abruptly called off a joint press conference after tense closed-door negotiations failed to yield progress on key diplomatic questions, including the transfer of a key US-controlled prison to Afghan hands.
The American military formally ceded control of all but a ?small number? of prisoners in that facility, known as Bagram Prison, to the Afghans during Kerry?s visit Monday.
This marks the formal completion of a transfer of 4,000 Bagram prisoners that began a year ago, but hit several snags over perceived security threats. The US military, however, will continue to hold in its custody around 50 high-level foreign prisoners considered ?enduring security threats,? along with hundreds of Afghans arrested since the initial transfer deal was authorized last March, reports Russia Today.
Despite its limitations, however, the transfer has potent symbolic value for Afghanistan, writes The New York Times.
Bagram Prison was the most flagrant symbol of Mr. Karzai?s lack of control. Americans detained several thousand Afghans there, and Mr. Karzai had no power to release them. His effort to wrest the prison from the Americans began in earnest more than year ago, and nearly succeeded at least twice, most recently two weeks ago, a day before Mr. Hagel?s first visit.
Each time, American military commanders backed out because of worries that the Afghans might release Taliban prisoners, who would return to the battlefield and endanger American soldiers. This time, despite those concerns, the transfer went forward.
?It?s about a shift that?s going on in how the U.S. is looking at what?s important,? said one American official knowledgeable about detention issues. ?We have to look at the larger picture: What?s the U.S. strategic interest here??
Kerry rounded out his visit Tuesday by meeting with democracy activists and female entrepreneurs at the American Embassy in Kabul. There, he traded headers with the captain of the Afghan women?s national soccer team and lauded civic leaders preparing for the 2014 elections, according to the Associated Press.
"You're engaged in a remarkable effort and the whole world is watching," Kerry said.
RECOMMENDED: How well do you know Afghanistan? Take our quiz.
A paradox for young docs: New work-hour restrictions may increase, not decrease, errorsPublic release date: 25-Mar-2013 [ | E-mail | Share ]
Contact: Kara Gavin kegavin@umich.edu 734-764-2220 University of Michigan Health System
U-M-led study of 2,300 1st-year residents questions impact of 2011 duty rules
ANN ARBOR, Mich. At hospitals around the country, young doctors fresh out of medical school help care for patients of all kinds and work intense, long hours as part of their residency training.
Traditionally, residents were allowed to work more than 24 hours without a break. In 2011, new rules cut back the number of hours they can work consecutively to 16, in the name of protecting patients from errors by sleepy physicians.
But a new study of more than 2,300 doctors in their first year of residency at over a dozen hospital systems across the country raises questions about how well the rules are protecting both patients and new doctors.
While work hours went down after new rules took effect in 2011, sleep hours didn't go up significantly and risk of depression symptoms in the doctors stayed the same, according to a new paper published online in JAMA Internal Medicine by a team led by University of Michigan Medical School researchers.
Most concerning: the percentage of residents reporting that they had committed medical errors that harmed patients went up after the new rules took effect.
The results, especially the increase in errors, surprised Srijan Sen, M.D., Ph.D., the U-M psychiatrist who is the report's first author.
"In the year before the new duty hour rules took effect, 19.9 percent of the interns reported committing an error that harmed a patient, but this percentage went up to 23.3 percent after the new rules went into effect," he says. "That's a 15 to 20 percent increase in errors -- a pretty dramatic uptick, especially when you consider that part of the reason these work-hour rules were put into place was to reduce errors."
The findings echo anecdotal reports about the impact of the 2011 duty hour rules.
Co-author Sudha Amarnath, M.D., a resident in the radiation oncology program at the University of Washington, says, "Many interns entering after the new work hour restrictions took effect felt that they were expected to do the same amount of work as in previous years, but in a more limited amount of time, leading to more harried and tiring work schedules despite working fewer hours. Overall, they felt that there was less 'down time' during the work day compared to pre-2011 work schedules, which may partially explain some of the unexpected findings."
Breck Nichols, M.D., MPH, the program director of the combined Internal Medicine and Pediatrics residency program at the University of Southern California, and another co-author on the paper, concurs.
"In 2000 a typical call day lasted 36 hours. We have very specifically reduced that for interns from 36 hours to 30 hours in 2003, and now with the latest 2011 work hours change it has been reduced even further to 16 hours," he says. "For most programs the significant reduction in work hours has not been accompanied by any increase in funding to offload the work. As a result, though many programs have made some attempts to account for this lost work in other ways, the end result is that current interns have about 20 less hours each week to complete the same or only slightly less work. If we know that timed tests result in more errors than untimed ones, we should not be surprised that giving interns less time to complete the same amount of work would increase their errors as well."
All the interns assessed in this study were working under the duty hour restrictions that went into effect in 2003 limiting residents to no more than 80 hours of work in a week, and other restrictions. Some studies have suggested that these rule changes, recommended by the Accreditation Council for Graduate Medical Education, did result in better safety for patients cared for by residents. But in an effort to achieve even greater safety, the ACGME recommended further changes that were implemented in 2011.
Each year, Sen and colleagues send out surveys to students entering residency programs around the U.S. The research team then surveys these interns every three months throughout that first year, asking questions that gauge mental health, overall well-being, sleep habits, work hours and performance on the job.
By comparing the interns serving before the new ACGME rules (called the 2009 and 2010 cohorts) with the interns serving after the new rules were implemented (the 2011 cohort), the research team assessed the effects of the new duty hour rules.
In addition to the increase in self-reported medical errors, 20 percent of the residents screened positive for depression.
Sen was an intern in 2006, and in the years since has studied depression among medical students and residents, said he had been in favor of the adjusting duty hour rules in principle. "It was obvious that after working for 24 hours, we were not functioning at our best, and this was not optimal for us or the patients we were treating," he explains. But in practice, he says, the new rules may have had unintended consequences that ran counter to the goals of new guidelines.
In addition to "work compression", he says, residents now hand off responsibility for a long list of patients more frequently than in the past. Communication between the intern who is ending a shift, and the one beginning a shift, may not cover all patients in detail, he suggests, and this gap in communication may not become apparent until an urgent situation arises with one of the patients.
He also said the increase in errors may come back down with time. "The 2011 changes were a pretty radical shift," he notes. "Doctors have worked 30-hour shifts for decades, and it may just take time for all parts of the health care system to get used to the new rules and adjust."
But, he cautions, the new data don't definitively support any one of these theories as the culprit in the rise in error rates or the lack of progress in sleep hours and well-being among young doctors. Further study is needed to assess what's happening and determine how to better support young doctors in during their stressful training and keep the patients that they treat as safe as possible.
###
The Intern Health Study, from which the new results are drawn, is funded by the National Institutes of Health (grants UL1RR024986, MH095109 and AA013736) with additional support from the American Foundation for Suicide Prevention. In addition to Sen, Amarnath and Nichols, the paper's authors include Joseph Kolars, M.D., senior associate dean for education and global at the U-M Medical School, Gregory Dalack, M.D., chair of the U-M Department of Psychiatry, Henry R. Kranzler, M.D., from the University of Pennsylvania; Aashish K. Didwania, M.D., from Northwestern University; Ann C. Schwartz, M.D., from Emory University; and Constance Guille, M.D. from the Medical University of South Carolina. REFERENCE: JAMA Internal Medicine, March 25, 2013
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AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
A paradox for young docs: New work-hour restrictions may increase, not decrease, errorsPublic release date: 25-Mar-2013 [ | E-mail | Share ]
Contact: Kara Gavin kegavin@umich.edu 734-764-2220 University of Michigan Health System
U-M-led study of 2,300 1st-year residents questions impact of 2011 duty rules
ANN ARBOR, Mich. At hospitals around the country, young doctors fresh out of medical school help care for patients of all kinds and work intense, long hours as part of their residency training.
Traditionally, residents were allowed to work more than 24 hours without a break. In 2011, new rules cut back the number of hours they can work consecutively to 16, in the name of protecting patients from errors by sleepy physicians.
But a new study of more than 2,300 doctors in their first year of residency at over a dozen hospital systems across the country raises questions about how well the rules are protecting both patients and new doctors.
While work hours went down after new rules took effect in 2011, sleep hours didn't go up significantly and risk of depression symptoms in the doctors stayed the same, according to a new paper published online in JAMA Internal Medicine by a team led by University of Michigan Medical School researchers.
Most concerning: the percentage of residents reporting that they had committed medical errors that harmed patients went up after the new rules took effect.
The results, especially the increase in errors, surprised Srijan Sen, M.D., Ph.D., the U-M psychiatrist who is the report's first author.
"In the year before the new duty hour rules took effect, 19.9 percent of the interns reported committing an error that harmed a patient, but this percentage went up to 23.3 percent after the new rules went into effect," he says. "That's a 15 to 20 percent increase in errors -- a pretty dramatic uptick, especially when you consider that part of the reason these work-hour rules were put into place was to reduce errors."
The findings echo anecdotal reports about the impact of the 2011 duty hour rules.
Co-author Sudha Amarnath, M.D., a resident in the radiation oncology program at the University of Washington, says, "Many interns entering after the new work hour restrictions took effect felt that they were expected to do the same amount of work as in previous years, but in a more limited amount of time, leading to more harried and tiring work schedules despite working fewer hours. Overall, they felt that there was less 'down time' during the work day compared to pre-2011 work schedules, which may partially explain some of the unexpected findings."
Breck Nichols, M.D., MPH, the program director of the combined Internal Medicine and Pediatrics residency program at the University of Southern California, and another co-author on the paper, concurs.
"In 2000 a typical call day lasted 36 hours. We have very specifically reduced that for interns from 36 hours to 30 hours in 2003, and now with the latest 2011 work hours change it has been reduced even further to 16 hours," he says. "For most programs the significant reduction in work hours has not been accompanied by any increase in funding to offload the work. As a result, though many programs have made some attempts to account for this lost work in other ways, the end result is that current interns have about 20 less hours each week to complete the same or only slightly less work. If we know that timed tests result in more errors than untimed ones, we should not be surprised that giving interns less time to complete the same amount of work would increase their errors as well."
All the interns assessed in this study were working under the duty hour restrictions that went into effect in 2003 limiting residents to no more than 80 hours of work in a week, and other restrictions. Some studies have suggested that these rule changes, recommended by the Accreditation Council for Graduate Medical Education, did result in better safety for patients cared for by residents. But in an effort to achieve even greater safety, the ACGME recommended further changes that were implemented in 2011.
Each year, Sen and colleagues send out surveys to students entering residency programs around the U.S. The research team then surveys these interns every three months throughout that first year, asking questions that gauge mental health, overall well-being, sleep habits, work hours and performance on the job.
By comparing the interns serving before the new ACGME rules (called the 2009 and 2010 cohorts) with the interns serving after the new rules were implemented (the 2011 cohort), the research team assessed the effects of the new duty hour rules.
In addition to the increase in self-reported medical errors, 20 percent of the residents screened positive for depression.
Sen was an intern in 2006, and in the years since has studied depression among medical students and residents, said he had been in favor of the adjusting duty hour rules in principle. "It was obvious that after working for 24 hours, we were not functioning at our best, and this was not optimal for us or the patients we were treating," he explains. But in practice, he says, the new rules may have had unintended consequences that ran counter to the goals of new guidelines.
In addition to "work compression", he says, residents now hand off responsibility for a long list of patients more frequently than in the past. Communication between the intern who is ending a shift, and the one beginning a shift, may not cover all patients in detail, he suggests, and this gap in communication may not become apparent until an urgent situation arises with one of the patients.
He also said the increase in errors may come back down with time. "The 2011 changes were a pretty radical shift," he notes. "Doctors have worked 30-hour shifts for decades, and it may just take time for all parts of the health care system to get used to the new rules and adjust."
But, he cautions, the new data don't definitively support any one of these theories as the culprit in the rise in error rates or the lack of progress in sleep hours and well-being among young doctors. Further study is needed to assess what's happening and determine how to better support young doctors in during their stressful training and keep the patients that they treat as safe as possible.
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The Intern Health Study, from which the new results are drawn, is funded by the National Institutes of Health (grants UL1RR024986, MH095109 and AA013736) with additional support from the American Foundation for Suicide Prevention. In addition to Sen, Amarnath and Nichols, the paper's authors include Joseph Kolars, M.D., senior associate dean for education and global at the U-M Medical School, Gregory Dalack, M.D., chair of the U-M Department of Psychiatry, Henry R. Kranzler, M.D., from the University of Pennsylvania; Aashish K. Didwania, M.D., from Northwestern University; Ann C. Schwartz, M.D., from Emory University; and Constance Guille, M.D. from the Medical University of South Carolina. REFERENCE: JAMA Internal Medicine, March 25, 2013
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Public release date: 28-Mar-2013
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