Monday, March 25, 2024

Scientists explore complex pattern of tipping points in the Atlantic’s current system

New mathematical modelling of the Atlantic meridional overturning circulation – a system of ocean currents – shows greater complexity than previously thought

UNIVERSITY OF LEICESTER

An international team of scientists have warned against relying on nature providing straightforward ‘early warning’ indicators of a climate disaster, as new mathematical modelling shows new fascinating aspects of the complexity of the dynamics of climate.

It suggests that the climate system could be more unpredictable than previously thought.

By modelling the Atlantic meridional overturning circulation, one of the main ocean current systems, the team which included mathematicians from the University of Leicester have found that the stability of the system is much more complex than simple ‘on-off’ states as previously assumed. Switches between these states might lead to major changes in the regional climate of the North Atlantic region, yet a far cry from the massive impacts of a transition between the qualitatively different states.

But some of these minor transitions might eventually upscale to cause a major changeover between the qualitatively different states, with massive global climatic impacts. Early warning signals might be unable to distinguish the degree of severity of the ensuing tipping points. Like a tower of Jenga blocks, removing some blocks may affect the stability of the system, but we cannot be certain which block will bring the whole system tumbling down.

Their findings are published in Science Advances today (22 March) in a paper led by the Niels Bohr Institute at the University of Copenhagen.

The Atlantic meridional overturning circulation is one of the most important fundamental features of the climate system. It transports heat from low to high latitudes in the northern Atlantic, so it helps create positive thermal anomalies in northern and western Europe and in the North Atlantic region downwind. A slowdown of the circulation would result in a relative cooling in this region.

Predicting the behaviour of our climate, as in the Atlantic meridional overturning circulation, is challenging due to its incredible complexity. Scientists either need a model of the highest possible resolution, or try to understand its behaviour using a less resource intensive model that allows for rigorous statistical analysis.

Professor Valerio Lucarini from the University of Leicester School of Mathematical and Computer Science said: “Within each state there is a multiplicity of nearby states. Depending on where or what you are observing, you might find some indicators of nearing collapse. But it is not obvious whether this collapse will be contained to nearby states or lead to a major upheaval, because the indicators only reflect the local properties of the system.

“These states are the different ways that the Atlantic meridional overturning circulation organises itself at large scales, with key implications for the global climate and especially regionally in the North Atlantic. Under some scenarios, the circulation could reach a ‘tipping point’ where the system is no longer stable and will collapse. Early warning indicators tell us that the system might be jumping to another state, but we do not know how different it will be.

“In a separate investigation we have seen something similar occurring in paleoclimatic records: when you change your timescale of interest – just like a magnification lens - you can discover smaller and smaller scale distinct features that are indicative of competing modes of operation of the global climate. Paleoclimatic records of the last 65 million years allowed us to provide a new interpretation of the climate evolution over that time period, and reveal these multiple competing states.

“This study paves the way to looking at the climate through the lens of statistical mechanics and complexity theory. It really stimulates a new outlook of climate, in which you have to put together complex numerical simulations, observational evidence and theory in an unavoidable mixture. You have to appreciate and endorse this complexity. There is no shortcut, no free lunch in our understanding of climate, but we are learning a lot from it.”

‘Multistability and Intermediate Tipping of the Atlantic Ocean Circulation’ is published in Science Advances by Johannes Lohmann (Niels Bohr Institute, University of Copenhagen, Denmark), Henk A. Dijkstra (Utrecht University, Utrecht, the Netherlands), Markus Jochum (Niels Bohr Institute, University of Copenhagen, Denmark), Valerio Lucarini (University of Leicester) and Peter D. Ditlevsen (Niels Bohr Institute, University of Copenhagen, Denmark). More information, including a copy of the paper, can be found online at the Science Advances press package at https://www.eurekalert.org/press/vancepak/
Further background: ‘A punctuated equilibrium analysis of the climate evolution of cenozoic exhibits a hierarchy of abrupt transitions’ in Scientific Reports, DOI: 10.1038/s41598-023-38454-6, Link: https://doi.org/10.1038/s41598-023-38454-6
The project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 820970 for the project TiPES, and from Danmarks Frie Forskningsfond under grant No. 2032-00346B, and by the European Research Council through the ERC-AdG project TAOC (project 101055096).

JOURNAL

Science Advances

ARTICLE TITLE

Multistability and Intermediate Tipping of the Atlantic Ocean Circulation

ARTICLE PUBLICATION DATE

22-Mar-2024

New findings shed light on finding valuable ‘green’ metals

How concentrations of metals can be transported from deep within the Earth's interior mantle by low temperature, carbon-rich melts

MACQUARIE UNIVERSITY

Research led by Macquarie University sheds new light on how concentrations of metals used in renewable energy technologies can be transported from deep within the Earth's interior mantle by low temperature, carbon-rich melts.

The findings published this week in the journal Science Advances may assist global efforts to find these valuable raw materials.

An international team led by Dr Isra Ezad, a postdoctoral research fellow from Macquarie University’s School of Natural Sciences, carried out high pressure and high temperature experiments creating small amounts of molten carbonate material at conditions similar to those around 90 kilometres depth in the mantle, below the Earth’s crust.

Their experiments showed carbonate melts can dissolve and carry a range of critical metals and compounds from surrounding rocks in the mantle – new information that will inform future metal prospecting.

“We knew that carbonate melts carried rare earth elements, but this research goes further,” says Dr Ezad.

“We show this molten rock containing carbon takes up sulfur in its oxidised form, while also dissolving precious and base metals – ‘green’ metals of the future – extracted from the mantle.”

Most of the rock that lies deep in the Earth’s crust and below in the mantle is silicate in composition, like the lava that comes out of volcanoes.

However a tiny proportion (a fraction of a percent) of these deep rocks contain small amounts of carbon and water that causes them to melt at lower temperatures than other portions of the mantle.

These carbonate melts effectively dissolve and transport base metals (including nickel, copper and cobalt), precious metals (including gold and silver), and oxidised sulfur, distilling these metals into potential deposits.

“Our findings suggest carbonate melts enriched in sulfur may be more widespread than previously thought, and can play an important role in concentrating metal deposits," says Dr Ezad.

The researchers used two natural mantle compositions: a mica pyroxenite from western Uganda and a fertile spinel lherzolite from Cameroon.

Thicker continental crust regions tend to form in older inland regions of continents, where they can act as a sponge, sucking up carbon and water, Dr Ezad says.

“Carbon-sulfur melts appear to dissolve and concentrate these metals within discrete mantle regions, moving them into shallower crustal depths, where dynamic chemical processes can lead to ore deposit formation," Dr Ezad says.

Dr Ezad says that this study indicates that tracking carbonate melts could give us a better understanding of large-scale metal redistribution and ore formation processes over Earth's history.

“As the world transitions away from fossil fuels to battery, wind and solar technology, demand for these essential metals is skyrocketing, and it’s becoming harder to find reliable sources,” says Dr Ezad.

“This new data provides us with a mineral exploration space previously not considered for base and precious metals – deposits from carbonate melts,” she says.

The multi-institution team were from Macquarie University in Sydney, the University of Western Australia in Perth, University of Oxford in the UK and Australian National University, Canberra.

END

Incipient carbonate melting drives metal and sulfur mobilization in the mantle was published in Science Advances on 22 March 2024. DOI: 10.1126/sciadv.adk5979

JOURNAL

Science Advances

DOI

10.1126/sciadv.adk5979

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

New findings shed light on finding valuable ‘green’ metals

ARTICLE PUBLICATION DATE

22-Mar-2024

COI STATEMENT

All authors declare that they have no competing interests. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOR Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Authors acknowledge the facilities, and the scientific and technical assistance of Microscopy Australia and the Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, a facility funded by the University, State and Commonwealth Governments of Australia. High-resolution SEM images were created at Macquarie University. Beamtime operations were performed on GSECARS 13-IDE. Synchrotron XRF mapping and S-XANES data were collected during beam time awarded to I.S.E. Portions of this work were performed at GeoSoilEnviroCARS (The University of Chicago, Sector 13-IDE), Advanced Photon Source (APS), Argonne National Laboratory. GeoSoilEnviroCARS is supported by the National Science Foundation – Earth Sciences (EAR-1634415).

MSU offers first study on teacher effectiveness for students with and without disabilities

Peer-Reviewed Publication

MICHIGAN STATE UNIVERSITY

EAST LANSING, Mich. – Research has often focused on how teachers and educators can best instruct and accommodate students with disabilities. However, are the methods used to teach students with disabilities effective and inclusive for all students? Michigan State University researchers are some of the first to answer that question.

Faculty and doctoral students from across MSU, including from the College of Social Science and the College of Education, offer some of the first findings on differentiating the effectiveness of instruction for students with and without disabilities.

Their study suggests that to help schools make decisions that are best for student outcomes, policymakers may want to consider teacher quality measures that look separately at these student groups.

Published in the journal Educational Evaluation and Policy Analysis, this research presents a major breakthrough in understanding how to best measure achievement for both students with and without disabilities.

“Most students with disabilities spend most of their school day in general education classrooms, but many teachers indicate they receive insufficient training and preparedness to educate these students,” said Scott Imberman, study author and professor in the Department of Economics in the College of Social Science and the College of Education. “We thought that through the use of statistical measures of teacher quality, we could identify which teachers are more effective teachers with these students and how much general education teachers’ ability to instruct these students varies.”

It’s important that students with disabilities have access to high-quality teachers, and not all teachers receive the necessary training and skills to support those students. They also can struggle more with certain subjects, such as math. Student success outcomes are also often determined by how the entire class performs rather than how individual students perform.

When it comes to evaluating the success of all students, numerical measures known as value-added measures, or VAM, are typically used. However, these measures often do not distinguish between evaluating students with and without disabilities.

The MSU research team created a study using data from the Los Angeles Unified School District due to the large number of enrollees and students with disabilities. They created two specific value-added measures — one for evaluating the effectiveness for teachers instructing students with disabilities and the other for students without disabilities.

They found that some of the best-performing teachers for students without disabilities have lower value-added scores for students with disabilities. Similarly, they noted that top-performing teachers for students with disabilities have lower value-added scores for students without disabilities. This means that some students who may appear to be matched with a high-quality teacher could actually be better off with other teachers.

The bigger inequity, according to Imberman, is that although “some general education teachers do have specialized skills that make them more effective for students with disabilities, our case study in Los Angeles suggested disabled students are typically not matched to these teachers.”

While the results do not identify how to better match teachers with students with disabilities, they do raise the point to schools and policymakers to explore how both groups of students and, especially those with disabilities, can have better academic gains. It is also necessary that educators, especially those who have been teaching longer, receive the appropriate training to support students with disabilities.

“We hope that our methods can be used in the future to help school officials better match students with disabilities to the teachers who are best equipped to instruct them and better assess which teachers might need additional training in educating disabled students,” Imberman said.

In addition to Imberman, the research team included Katharine Strunk, dean of the University of Pennsylvania’s Graduate School of Education; Nathan Jones, associate professor in the Special Education program at Boston University Wheelock College of Education and Human Development; W. Jesse Wood, senior analyst at Abt Associates; Neil Filosa, doctoral student in the MSU Department of Economics; and Ijun Lai, researcher with Mathematica.

Read on MSUToday.

###

Michigan State University has been advancing the common good with uncommon will for more than 165 years. One of the world’s leading public research universities, MSU pushes the boundaries of discovery to make a better, safer, healthier world for all while providing life-changing opportunities to a diverse and inclusive academic community through more than 400 programs of study in 17 degree-granting colleges.

For MSU news on the web, go to MSUToday or twitter.com/MSUnews.

JOURNAL

Educational Evaluation and Policy Analysis

DOI

10.3102/01623737231214555

ARTICLE TITLE

Are Effective Teachers for Students With Disabilities Effective Teachers for All?

New classification of tuberculosis to support efforts to eliminate the disease

A new way to classify tuberculosis (TB) that aims to improve focus on the early stages of the disease has been presented by an international team involving researchers at UCL (University College London).

Peer-Reviewed Publication

UNIVERSITY COLLEGE LONDON

A new way to classify tuberculosis (TB) that aims to improve focus on the early stages of the disease has been presented by an international team involving researchers at UCL.

The new framework, published in The Lancet Respiratory Medicine, seeks to replace the approach of the last half century of defining TB as either active (i.e., causing illness and potentially infectious to others) or latent (being infected with the bacterium that causes TB [M tuberculosis] but feeling well and not infectious to others) – an approach researchers say is limiting progress in eradicating the disease.

Of note, large surveys conducted in over 20 countries recently have shown than many people with infectious TB feel well.

Under the new classification, there are four disease states: clinical (with symptoms) and subclinical (without symptoms), with each of these classed as either infectious or non-infectious. The fifth state is M. tuberculosis infection that has not progressed to disease – that is, M tuberculosis may be present in the body and alive, but there are no signs of the disease that are visible to the naked eye, for example with imaging.

The researchers say they hope the International Consensus for Early TB (ICE-TB) framework, developed by a diverse group of 64 experts, will help lead to better diagnosis and treatment of the early stages of TB which have historically been overlooked in research.

TB remains the world’s most deadly infectious disease currently and has caused over one billion deaths in the last 200 years. An estimated three million cases a year are not reported to health systems and more than half of these cases will be asymptomatic.

The international team was led by researchers at UCL, London School of Hygiene & Tropical Medicine, The Walter and Eliza Hall Institute (WEHI), University of Cape Town, Imperial College London and the South African Medical Research Council.

Dr Hanif Esmail, co-lead author at the UCL Institute for Global Health and MRC Clinical Trials Unit at UCL, said: “The binary paradigm of active disease versus latent infection has resulted in a one-size-fits-all antibiotic treatment for disease, but designed for those with the most severe form of disease. This leads to potential over-treatment of individuals with subclinical TB.

“A key research priority now is to identify the best combination, dosage and duration of antibiotics to treat each TB state, as well as the benefits of treating the subclinical states.”

Professor Rein Houben (London School of Hygiene and Tropical Medicine), co-lead author of the paper, said: “While providing treatment to people who become very sick with TB has saved millions of lives we are not stopping transmission of the disease.”

“To prevent transmission of TB, we need to move away from focusing just on the very sick and look at earlier disease states, identifying people who may be infectious for months or years before they develop TB symptoms.

“Our consensus framework replaces the old binary concept of ‘active’ versus ‘latent’ TB with a more detailed classification system that we hope, if widely adopted, could help to improve treatment for those with early-stage TB and drive forward efforts to eradicate the disease.”

The framework was developed via a Delphi process designed to reach a consensus among a diverse group. The process began with a scoping review of papers and online surveys of experts and culminated in a two-day meeting in Cape Town, South Africa, of researchers from a range of disciplines as well as policymakers, clinicians, and TB survivors.

Dr Anna Coussens, co-lead author from WEHI, said: “One key finding in the consensus is moving the disease threshold and acknowledging that disease does not just start with symptoms or transmission, but when tissue is damaged.

“In time we hope our framework can contribute to TB elimination by leading to improved early diagnosis and treatment, optimising patient outcomes and minimising transmission.”

The researchers noted that the disease process was non-linear – that people may fluctuate between infectious and non-infectious states, and between the presence and absence of symptoms or signs.

They also said that better diagnostic tools were needed to identify many of the TB states. For instance, there is currently no test to detect a viable M tuberculosis infection (i.e., one where the bacteria are physiologically active), as opposed to a non-viable infection or recent infection that has cleared.

The international team involved stakeholders from 19 countries including International Union Against TB and Lung Disease, The StopTB partnership, World Health Organization, FIND, National TB Programmes, TB Proof, and researchers from a number of universities and medical research institutes.

The work was supported by Wellcome, the National Institutes of Health/RePORT RSA, the Bill and Melinda Gates Foundation, the Medical Research Council, the European Research Council, and the National Health and Medical Research Council.

JOURNAL

The Lancet Respiratory Medicine

DOI

10.1016/S2213-2600(24)00028-6

METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

International consensus classification of early tuberculosis states to guide research for improved care and prevention: A Delphi exercise

ARTICLE PUBLICATION DATE

22-Mar-2024

RaDPi-U: A fast and convenient drug screening with urine samples

Researchers develop a rapid urine test that can detect 40 drugs reliably in as little as three minutes.

Peer-Reviewed Publication

KINDAI UNIVERSITY

Breakthrough advancement in urine drug screening. — IMAGE:
THE RADPI-U TECHNIQUE IS EXTREMELY SIMPLE TO PERFORM AND PRODUCES RELIABLE DRUG SCREENING RESULTS IN LESS THAN THREE MINUTES. WITH MANY ADVANTAGES COMPARED TO CONVENTIONAL SCREENING METHODS, IT IS POISED TO BECOME A POWERFUL TOOL FOR FORENSIC INVESTIGATORS.
view more
CREDIT: DR. ISSEY TAKAHASHI FROM NAGOYA UNIVERSITY

Drugs, both legal and illegal, cause millions of cases of severe intoxication every year, leading to health complications and even fatalities. Often, they are also implicated in violent and sexual harassment crimes, as well as accidents. Obtaining detailed information about the drugs consumed by a criminal or victim is often challenging. Forensic professionals rely on drug screening techniques performed on biological samples, such as blood or saliva, to gather crucial evidence.

Today, various types of practical drug screening methods exist, each with their own unique advantages and drawbacks. For example, immunological drug screening tests can provide results quickly, but are limited to very specific drugs and often show false positives. In contrast, techniques based on mass spectrometry (MS), which analyze the mass-to-charge ratio of captured ions, tend to be more accurate. However, conventional MS approaches require careful sample preparation steps, which makes them somewhat tedious and difficult to use for non-experts.

Against this background, a research team from Japan has developed a promising drug screening technique dubbed “RaDPi-U” that can rapidly detect the presence of 40 forensically relevant drugs from urine samples. Their study, detailing the performance of their approach in preliminary tests, was published in the journal Analytical and Bioanalytical Chemistry on March 25, 2024. Members of this research team included Professor Kei Zaitsu from Kindai University, Dr. Kazuaki Hisatsune of the Forensic Science Laboratory at Aichi Prefectural Police Headquarters, Dr. Akira Iguchi of the Research Laboratory on Environmentally-conscious Developments and Technologies (E-code), National Institute of Advanced Industrial Science and Technology (AIST), Dr. Masaru Taniguchi of Nagoya City Public Health Research Institute, and Dr. Tomomi Asano of Kinjo Gakuin University.

The proposed technique is based on a combination of probe electrospray ionization and tandem mass spectrometry (PESI-MS/MS). Simply put, PESI involves capturing molecules to be analyzed using a thin metal probe, which induces a strong electric field that ionizes compounds adsorbed onto the surface of the probe. These captured molecules, or “analytes,” are transferred to a series of mass spectrometers, which determine the mass-to-charge ratio and additional structural information to determine the concentration of specific compounds (drugs).

The procedure for RaDPi-U is extremely simple, requiring only a few steps. First, 10 microliters of urine are collected from the screened individual and mixed with a substance predetermined as an internal standard, and ethanol. Then, after thoroughly mixing the sample using a vortex mixer (pre-treatment: 1.5 minutes), the same is pipetted and laid onto a sample plate for PESI. Finally, the plate is set into the PESI-MS/MS (analysis time: 1.5 minutes), which produces results in less than three minutes and automatically reports them using a built-in software.

The researchers carefully investigated the reliability and accuracy of the results for multiple concentrations of each of the 40 screened drugs. Compared to established methods, the proposed technique exhibited an equal or better lower limit of detection for all drugs, meaning that it can detect drug concentrations as minuscule as fractions of a nanogram per microliter for several compounds. Moreover, the measurements were highly repeatable, demonstrating the reliability of RaDPi-U. This was further proved through tests with postmortem urine samples. To top things off, this method requires only one single substance as an internal standard rather than a specific compound for each screened drug, which means setting up the device is straightforward.

Overall, the team has high hopes that RaDPi-U will prove to be a powerful tool for forensic departments everywhere. “Our method boasts simplicity and user-friendliness, enabling even non-professionals to conduct drug analysis with ease,” remarks Prof. Zaitsu. “In essence, our research streamlines drug analysis to unprecedented levels, thereby fostering long-term efforts to curb drug-related crimes.” He also notes that RaDPi-U has potential not only in forensic fields but also in tasks related to clinical toxicology.

Additional efforts are already underway to make the proposed method even more useful. “While this study is preliminary and the number of currently detectable drugs is limited to 40, we are actively expanding the range of targeted substances, aiming to enhance both the speed and scope of detection,” comments Dr. Hisatsune. The researchers are also developing a similar method for blood samples, called RaDPi-B, which will be essential when urine samples are unavailable or in case of drugs for which urine-based testing is not applicable.

Let us hope these promising techniques will serve as a stepping stone toward a world free from the scourge of drug abuse.

JOURNAL

Analytical and Bioanalytical Chemistry

DOI

10.1007/s00216-024-05215-x

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Human tissue samples

ARTICLE TITLE

Development of a rapid-fire drug screening method by probe electrospray ionization tandem mass spectrometry for human urine (RaDPi-U)

ARTICLE PUBLICATION DATE

24-Mar-2024

Physician work hours, especially for male doctors, have declined since 1987

CANADIAN MEDICAL ASSOCIATION JOURNAL

Physicians in Canada, especially male physicians, are working fewer hours than they did 3 decades ago, and these long-term trends must be considered in workforce planning, according to new research in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.231166.

"Canadian physicians' work hours, crucial for health care access and planning, have seen a long-term decline, especially among male and married physicians, suggesting a shift towards better work–life balance," said Dr. Boris Kralj, Department of Economics, Centre for Health Economics & Policy Analysis, McMaster University, Hamilton, Ontario.

Using Statistics Canada's Labour Force Survey, researchers from McMaster University conducted a study on long-term trends in physician work hours, with data from 1987 to 2021. They hope that the findings will help governments make smart health care policy decisions, inform physician work force planning, and foster gender equity.

Highlights:

Compared with the general population, physicians worked more hours per week, about 20% more hours in 2021
Weekly physician hours decreased 13.5% from 52.7 hours per week in 1987 to 45.6 in 2019
Average hours worked by male physicians declined markedly beginning around 1997
No differences in declines in hours among urban versus rural settings, incorporated versus unincorporated physicians, physicians younger or older than 45 years, or those with or without children under age 5 years, were apparent
Hours worked varied by province, but these differences declined over time

The early part of the COVID-19 pandemic was associated with a 15% decline in working hours, with an 11% decline among male physicians and a 20% decline in hours worked by female physicians in the second quarter of 2020. However, by the end of 2020, hours worked reverted to prepandemic levels.

The study's authors suggest that a desire for better work–life balance may be driving these long-term trends. For a long time, doctors have been expected to work very long hours and be available all the time. This has led to unhealthy workplaces.

"[W]e propose that a shift in male physicians' preferences toward achieving better work–life balance is an important contributing factor. The question of whether these trends are related to physician burnout is relevant. Characterized by emotional exhaustion, depersonalization, detachment from work, and reduced personal accomplishment, burnout can lead to negative effects on health, lower productivity, reduced work hours, and even exiting medical practice," write the authors.

They found no evidence that higher payments contributed to physicians working fewer hours. The observed decrease in hours persisted during periods of both rising and stable payment levels.

These trends highlight the need for Canada to have enough doctors to meet its population's evolving needs. It is important for policy-makers to consider not just how many doctors there are, but also how many hours they work.

"The way forward will likely involve policy-makers increasing the size of the medical workforce — including physicians and other occupations involved in interdisciplinary care — faster than population growth to accommodate historical and potential future hour reductions (and increasing demand from an aging population)," write the authors.

JOURNAL

Canadian Medical Association Journal

DOI

10.1503/cmaj.231166

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Long-term trends in the work hours of physicians in Canada

ARTICLE PUBLICATION DATE

25-Mar-2024

Sweeping review reveals latest evidence on the diagnosis, treatment, and monitoring of ADHD

A comprehensive literature review from USC researchers summarizes the most robust findings on addressing ADHD in children and adolescents, which will inform updated clinical practice guidelines from the American Academy of Pediatrics

KECK SCHOOL OF MEDICINE OF USC

Hundreds of studies are published each year on attention deficit hyperactivity disorder (ADHD), but more work is needed to ensure those findings improve lives.

With input from expert stakeholders across the field, researchers at the Southern California Evidence Review Center, part of the Keck School of Medicine of USC, have synthesized the latest insights so that they can ultimately inform clinical practice. Broadly, they found that both medications and psychosocial treatments work for treating ADHD and that children with the condition can and do get better.

“We have more research than ever on ADHD, but we need to summarize it in a reliable and valid way,” said Susanne Hempel, PhD, a professor of clinical population and public health sciences at the Keck School of Medicine and director of the Southern California Evidence Review Center, who oversaw the work.

The team, which included researchers from the Southern California Evidence-based Practice Center, the Keck School of Medicine’s division of child psychiatry and the Children’s Hospital Los Angeles Behavioral Health Institute, reviewed more than 23,000 publications on ADHD. Their work was commissioned by the Agency for Healthcare Research and Quality and funded by the Patient-Centered Outcomes Research Institute.

The results, just published in two companion papers in the journal Pediatrics, answer big questions about what works to effectively diagnose and treat ADHD, and point to ongoing gaps in the research, including how best to monitor the condition’s progression over time. Clinicians selected by the American Academy of Pediatrics (AAP) will now use the evidence review to create updated clinical guidelines that inform best practices in ADHD care across the nation.

“Parents, teachers and providers need evidence-based information about ADHD,” Hempel said. “We included only the most robust studies in our review, which enables us to make strong evidence statements.”

New findings on diagnosis and treatment

Before beginning the literature review, the research team developed their questions and protocols in collaboration with ADHD experts across the field to ensure they were asking and answering questions that could directly benefit patients, families and providers. During the process, the researchers also posted their preliminary findings and welcomed feedback during a 45-day public comment period.

The team conducted an extensive search that was not restricted to diagnostic tools or treatment approaches already known to be effective. From more than 23,000 publications, the researchers selected 550 studies for the final analysis. Studies were selected if they met the team’s rigorous inclusion criteria, which prioritized rigorous study designs such as randomized controlled trials.

For diagnosis of ADHD, many tools are available, including parent and teacher rating scales, patient self-reports, neuropsychological tests, EEG approaches, imaging, biomarkers, activity monitoring and observation. For several approaches, the researchers found a substantial variation in results, with some studies indicating a given method was highly effective and others indicating that it performed poorly. “We’re getting better at diagnosing ADHD, but research is still characterized by a lot of variation,” Hempel said.

Many treatments for ADHD have been rigorously tested, building a strong evidence base for medications (including both stimulants and non-stimulants), as well as psychosocial approaches, such as behavior modification. Other non-drug treatments the team analyzed include cognitive training, neurofeedback, physical exercise, nutrition and supplements, parent support, and school interventions.

“Medications have the strongest evidence for improving not only ADHD symptoms, but also other problems that often accompany ADHD, such as oppositional and disruptive behaviors,” said Bradley Peterson, MD, director of the Institute for the Developing Mind at Children's Hospital Los Angeles (CHLA) and the lead author of the review.

Monitoring ADHD over time

In addition to reviewing the evidence on diagnosis and treatment, the researchers explored what is known about ongoing monitoring of ADHD: How can providers assess whether a child or adolescent needs to continue treatment for the condition? Experts across the field agreed that the question is a critical one, but few studies have explored the question. The evidence review team concluded that more research is needed on monitoring ADHD over time.

The publications will now be used to support an update of the AAP’s clinical practice guidelines for ADHD, providing up-to-date advice for how best to diagnose, evaluate and treat the condition.

“The overarching takeaway: ADHD is treatable. There are lots of studies that can show us that children absolutely can get better,” Hempel said.

About this research

In addition to Drs. Peterson and Hempel, the study’s other authors are Joey Trampush, Morah Brown, Margaret Maglione, Maria Bolshakova, Mary Rozelle, Jeremy Miles, Sheila Pakdaman and Aneesa Motala among others from the Southern California Evidence Review Center, Keck School of Medicine, University of Southern California.

This work is supported by the Agency for Healthcare Research and Quality [Contract No. 75Q80120D00009] and the Patient-Centered Outcomes Research Institute [Publication No. 2023-SR-03]. More information about AHRQ’s Effective Health Care program, which funds this work, may be found at: https://effectivehealthcare.ahrq.gov/about.

JOURNAL

PEDIATRICS

DOI

10.1542/peds.2024-065787

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Treatments for ADHD in Children and Adolescents: A Systematic Review

ARTICLE PUBLICATION DATE

25-Mar-2024