Trends in the Prevalence of Concussion Reported by US Adolescents, 2016-2020

Phil Veliz, PhD¹; Sean Esteban McCabe, PhD¹; James T. Eckner, MD, MS²; et alJohn E. Schulenberg, PhD³

Author Affiliations Article Information

JAMA. 2021;325(17):1789-1791. doi:10.1001/jama.2021.1538

In 2016, 19.5% of US adolescents reported at least 1 concussion during their lifetime.^1,2 While knowledge about concussion and management of these injuries within the adolescent population have increased over the past decade,³ to our knowledge, no national study has tracked whether rates of concussion have declined or increased. This study estimated trends in the lifetime prevalence of self-reported concussion among a national sample of adolescents between 2016 and 2020.

Methods

This study uses national cross-sectional data from the 2016-2020 Monitoring the Future (MTF) initiative.⁴ The MTF initiative is an annual school-based survey of 8th-, 10th-, and 12th-graders conducted between February and June each school year; surveys are administered in classrooms and completed during normal class periods. The MTF stopped data collection for the 2020 survey early on March 14, 2020, due to COVID-19 (a representative sample was still maintained). The student response rates between 2016 and 2020 ranged from 79% to 90%. The University of Michigan institutional review board approved this study. A waiver of informed consent was sent to parents providing them a means to decline their child’s participation.

A measure to assess concussion was added to the MTF in 2016, asking respondents the following: “Have you ever had a head injury that was diagnosed as a concussion?” Response options included “no,” “yes, once,” and “yes, more than once.” The measure did not change across the 5 years.

Binary regression models (using Mplus 8.1) estimated linear trends for self-reported concussion; adjusted models controlled for sex, race/ethnicity, grade level, parental education, and participation in sports. Analyses report the unadjusted prevalence ratios, adjusted prevalence ratios, and 95% CIs. Statistical significance was set at α ≤ .05 for a 2-tailed test when assessing linear trends. Full information maximum likelihood estimation was used to account for item missingness for each of the binary regression models. All analyses take into account the complex multistage sampling design, including clustering of respondents in primary sampling units⁴; weights were incorporated to provide nationally representative estimates along with adjusting for the different sample sizes for 8th-, 10th-, and 12th-graders.

Results

The sample consisted of 52 949 8th-, 10th-, and 12th-graders, of whom 50.3% were girls, and self-reported race/ethnicity was 45.0% White, 11.8% Black, 20.6% Hispanic, and 22.6% other (category included Asian American, American Indian or Alaska Native, and Native Hawaiian or other Pacific Islander) based on predefined categories. Lifetime prevalence of at least 1 self-reported concussion increased from 19.5% (95% CI, 18.5%-20.6%) in 2016 to 24.6% (95% CI, 22.5%-26.7%) in 2020 (adjusted prevalence ratio, 1.05; 95% CI, 1.03-1.08) (Table 1). The increase in lifetime prevalence of only 1 self-reported concussion (adjusted prevalence ratio, 1.05 [95% CI, 1.02-1.08]; 14.0% in 2016 vs 17.7% in 2020) and 2 or more self-reported concussions (adjusted prevalence ratio, 1.05 [95% CI, 1.01-1.11]; 5.5% in 2016 vs 6.8% in 2020) between 2016 and 2020 was statistically significant. Increases in any self-reported concussion were found across both sexes and race/ethnicity categories, among respondents whose parents had a high school diploma or less, and among respondents who participated in competitive sports during the past year (Table 2).

Discussion

Between 2016 and 2020, the estimated percentage of US 8th-, 10th-, and 12th-graders who reported at least 1 diagnosed concussion during their lifetime increased. Although lower prevalence of self-reporting concussions has been found among Hispanic, non-Hispanic other, and non-Hispanic Black adolescents compared with non-Hispanic White adolescents,⁵ these groups saw increases in self-reported concussion during this time period.

The study also found that trends in self-reporting concussion among adolescents who participate in competitive sports increased during this time period, in contrast with emergency department data that showed a decrease in sports/recreation-related traumatic brain injuries among adolescents and children between 2012 and 2018.⁶

The increase in reporting of concussion could be due to an increased incidence or greater recognition of symptoms associated with these injuries. Given greater effort to educate the US population regarding the risks associated with head injuries, more adolescents may be seeking care for these injuries, including care from health care professionals outside the emergency department who have appropriate diagnosis and management skills.³

Limitations of the study include the use of self-reported measures of concussion and the use of cross-sectional data. Continued efforts to monitor and prevent concussion are needed.

Section Editor: Jody W. Zylke, MD, Deputy Editor.

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Article Information

Corresponding Author: Phil Veliz, PhD, School of Nursing, Center for the Study of Alcohol, Smoking and Health, University of Michigan, Ann Arbor, MI 48109 (ptveliz@umich.edu).

Accepted for Publication: January 31, 2021.

Author Contributions: Dr Veliz had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: All authors.

Acquisition, analysis, or interpretation of data: Veliz, McCabe, Schulenberg.

Drafting of the manuscript: Veliz, McCabe.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Veliz.

Obtained funding: McCabe, Schulenberg.

Administrative, technical, or material support: Schulenberg.

Supervision: McCabe.

Other (contribution of concussion-specific content expertise): Eckner.

Conflict of Interest Disclosures: None reported.

Funding/Support: This work was supported by research grants R01DA001411 and R01DA031160 from the National Institute on Drug Abuse. The Monitoring the Future data were collected under grant R01DA001411.

Role of the Funder/Sponsor: The National Institute on Drug Abuse had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Disclaimer: The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Drug Abuse.

References

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Veliz  P.  Variation in national survey estimates and youth traumatic brain injury-where does the truth lie?   JAMA Pediatr. 2019;173(4):399. doi:10.1001/jamapediatrics.2019.0001
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Veliz  P, McCabe  SE, Eckner  JT, Schulenberg  JE.  Prevalence of concussion among US adolescents and correlated factors.   JAMA. 2017;318(12):1180-1182. doi:10.1001/jama.2017.9087
ArticlePubMedGoogle ScholarCrossref

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Halstead  ME, Walter  KD, Moffatt  K; Council on Sports Medicine and Fitness.  Sport-related concussion in children and adolescents.   Pediatrics. 2018;142(6):e20183074. doi:10.1542/peds.2018-3074PubMedGoogle Scholar

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Miech  RA, Johnston  LD, O’Malley  PM, Bachman  JG, Schulenberg  JE, Patrick  ME,. Secondary school students. In:  Monitoring the Future: National Survey Results on Drug Use, 1975-2018. Vol 1. Institute for Social Research, University of Michigan; 2020.

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Haarbauer-Krupa  J, Lebrun-Harris  LA, Black  LI,  et al.  Comparing prevalence estimates of concussion/head injury in US children and adolescents in national surveys.   Ann Epidemiol. 2021;54:11-20. doi:10.1016/j.annepidem.2020.11.006PubMedGoogle ScholarCrossref

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Waltzman  D, Womack  LS, Thomas  KE, Sarmiento  K.  Trends in emergency department visits for contact sports-related traumatic brain injuries among children—United States, 2001-2018.   MMWR Morb Mortal Wkly Rep.  2020;69(27):870-874. doi:10.15585/mmwr.mm6927a4PubMedGoogle ScholarCrossref

There is no evidence that associations between adolescents' digital technology engagement and mental health problems have increased

ASSOCIATION FOR PSYCHOLOGICAL SCIENCE

Research News

 

With the explosion in digital entertainment options over the past several decades and the more recent restrictions on outdoor and in-person social activities, parents may worry that excessive engagement with digital technology could have long-term effects on their children's mental health.

A new study published in the journal Clinical Psychological Science, however, found little evidence for an increased association between adolescents' technology engagement and mental health problems over the past 30 years. The data did not consistently support the suggestion that the technologies we worry about most (e.g., smartphones) are becoming more harmful.

The new study, which included 430,000 U.K. and U.S. adolescents, investigated the links between social media use and depression, emotional problems, and conduct problems. It also examined the associations between television viewing and suicidality, depression, emotional problems, and conduct problems. Finally, the study explored the association between digital device use and suicidality.

Of the eight associations examined in this research, only three showed some change over time. Social media use and television viewing became less strongly associated with depression. In contrast, social media's association with emotional problems did increase, although only slightly. The study found no consistent changes in technology engagement's associations with conduct problems or suicidality.

"If we want to understand the relationship between tech and well-being today, we need to first go back and look at historic data--as far back as when parents were concerned too much TV would give their kids square eyes--in order to bring the contemporary concerns we have about newer technologies into focus," said Matti Vuorre, a postdoctoral researcher at the Oxford Internet Institute and lead author on the paper.

The study also highlighted key factors preventing scientists from conclusively determining how technology use relates to mental health.

"As?more data accumulates on adolescents' use of emerging technologies, our knowledge of them?and their effects on mental health will become more precise," said Andy Przybylski, director of research at Oxford Internet Institute and senior author on the study. "So,?it's too soon to?draw?firm conclusions about the increasing, or declining, associations between social media and?adolescent mental health, and it is certainly way too soon to be making policy or regulation on this basis."?

"We need more transparent and credible collaborations between scientists and technology companies to unlock the answers. The data exists within the tech industry; scientists just need to be able to access it for neutral and independent investigation," Przybylski said.

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Reference: Vuorre, M., Orben, A., & Przybylski, A. (2021). There is no evidence that associations between adolescents' digital technology engagement and mental health problems have increased. Clinical Psychological Science. Advance online publication. https://doi.org/10.1177/2167702621994549

Chronic exposure to low levels of blast may be associated with neurotrauma

Exposure during occupational training is linked to biomarkers of brain damage

REMEMBER TRUMP DISMISSING THE BOMBING OF US TROOPS BY IRAN AFTER THE ASSISSINATION OF THE LEADER OF THE REVOLUTIONARY GUARDS

WALTER REED ARMY INSTITUTE OF RESEARCH

Research News

 

Scientists at the Walter Reed Army Institute for Research demonstrated that biomarkers associated with traumatic brain injury were elevated among law enforcement and military personnel, particularly in active duty participants with longer duration of service. Most notably, these elevated biomarker levels were observed in individuals without a diagnosed brain injury or concussion.

Some law enforcement and military personnel are regularly exposed to low levels of blast, particularly during training, due to the use of explosive charges and high caliber weapons. Understanding effects from these occupational exposures is a military health care priority to improve diagnosis and mitigation of ill effects.

While repeated exposure to low level blast is not known to result in clinically diagnosed traumatic brain injury, exposures have been linked to a series of reported symptoms such as headaches, fatigue, dizziness, memory difficulties, and tinnitus (ringing in the ears) -- collectively referred to as "breacher's brain" among members of affected communities.

This study, published in the Journal of the American Medical Association, measured neurotrauma biomarker concentrations in blood samples from 106 military and law enforcement personnel who were not actively engaged in training or physical activity at the time of blood collection and compared those concentrations with commercially available samples from individuals who were similar in sex and age but unlikely to have been exposed to blast.

"We found that five biomarkers previously associated with TBI and brain diseases were elevated among personnel when compared to controls," said Dr. Angela Boutte, lead author on the paper and a researcher at the WRAIR Brain Trauma Neuroprotection branch. "Given the difficulty of identifying and evaluating injury associated with repeated low level blast exposure, we hope these data are the first step in our collective goal to identify objective biomarkers as clinically relevant diagnostic tools."

Dr. Bharani Thangavelu and Dr. Walter Carr, WRAIR brain health researchers and co-authors, emphasized the potential impact of blast exposure experienced by military personnel stating, "Low level blast exposure in routine military training should not be expected to result in acute, gross behavioral deficits for the majority of personnel. However, repeated exposure across years does correlate with symptomology, especially when a history of chronic exposure is exacerbated by new, large magnitude exposures."

Efforts to identify and quantify the impact of blast and traumatic brain injury on Service Members have increased dramatically in recent years, including initiatives in response to Congressional mandates. Biomarkers of blast effects on brain health will be a useful tool in this effort, especially as tools that augment decision-making based on symptoms reported by personnel.

###

About the Walter Reed Army Institute of Research

Headquartered in Silver Spring, Maryland, the Walter Reed Army Institute of Research is the oldest and most mission-diverse biomedical research laboratory in the Department of Defense. WRAIR provides unique research capabilities and innovative solutions to a range of force health and readiness challenges currently facing U.S. Service Members, along with threats anticipated during future operations. With research units in the state of Washington, Africa, Asia and the Caucasus region, WRAIR houses three centers, the Center for Infectious Disease Research, the Center for Military Psychiatry and Neuroscience and the Center for Enabling Capabilities. For more information, visit https://www.wrair.army.mil.

The WRAIR Brain Trauma Neuroprotection and Blast Induced Neurotrauma Branches develop ground-breaking preventive, diagnostic, and therapeutic solutions to mitigate the effects of TBI at the point of injury to reduce morbidity and mortality.

Help for serious shopaholics

When does excessive buying become a disorder?

POST MODERN CAPITALISM IS CONSUMPTION NOT PRODUCTION

FLINDERS UNIVERSITY

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IMAGE: FLINDERS UNIVERSITY PROFESSOR OF PSYCHOLOGY MIKE KYRIOS view more 

CREDIT: FLINDERS UNIVERSITY

For the first time, international experts in psychology have built a framework to diagnose Compulsive Buying-Shopping Disorder - promising help for people struggling to manage their spending behaviour and mental wellbeing.

The new guidelines, published in the Journal of Behavioral Addictions, confirms that excessive buying and shopping can be so serious as to constitute a disorder, giving researchers and clinicians new powers to develop more targeted interventions for this debilitating condition.

The international collaboration, led by Professor Mike Kyrios from Flinders University's Órama Institute for Mental Health and Wellbeing and Professor Astrid Müller from the Hannover Medical School in Germany, say evidence-based criteria for Compulsive Buying-Shopping Disorder (CBSD) are long overdue.

The phenomenon of excessive or uncontrolled buying or shopping has been described in a clinical setting for more than a century. Surprisingly, to date there is no formally accepted diagnosis for the disorder, despite being a highly prevalent, disabling and growing problem that contributes to overconsumption and debt.

Professor Kyrios describes the findings as a "game-changer" for research in the area of excessive buying, providing a springboard for much-needed treatments and better diagnostic processes in the future.

"In over 20 years, since I started investigating excessive buying, there has been an absence of commonly agreed diagnostic criteria which has hampered the perceived seriousness of the problem, as well as research efforts and consequently the development of evidence-based treatments," Professor Kyrios says.

This will now be possible with the world's leading experts agreeing on diagnostic criteria for the disorder, he says.

In the study, 138 international experts (researchers and clinicians) from 35 countries were evaluated to develop a consensus about proposed diagnostic criteria.

A key feature of the new diagnostic criteria is "excessive purchasing of items without utilising them for their intended purposes", with excessiveness described as "diminished control over buying/shopping". Another characteristic of the disorder is that "buying/shopping is used to regulate internal states, e.g., generating positive emotions or relieving negative mood".

"Clients who show excessive buying behaviour commonly have difficulties in regulating their emotions, so buying or shopping is then used to feel better. Paradoxically, if someone with Compulsive Buying-Shopping Disorder goes on a shopping trip, this will briefly improve their negative feelings, but will soon lead to strong feelings of shame, guilt and embarrassment."

The Delphi research method was used to reach consensus from the panel of experts on a very complex psychological disorder.

"The Delphi technique is an ideal method to integrate diverse perspectives from international and interdisciplinary experts in the field of Compulsive Buying-Shopping Disorder," says co-investigator Dr Dan Fassnacht, Senior Lecturer in Psychology at Flinders University.

"This helped us to developed diagnostic criteria featuring large agreement among experts in the field, and is an important milestone to better understand and treat this behaviour."

Dr Kathina Ali, Research Fellow at Flinders University and co-investigator of the study adds: "Previously, it was difficult to compare studies without agreed criteria. Now for the first time, we can start examining Compulsive Buying-Shopping Disorder more precisely which should help us the improve our treatments for this disabling condition."

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The study was an international collaboration with researchers from the Hannover Medical School at the University of Duisburg-Essen and University of Dresden in Germany funded by the German Academic Exchange Service and Universities Australia.

The paper 'Proposed diagnostic criteria for compulsive buying-shopping disorder: A Delphi expert consensus study' (2021) by Astrid Müller, Nora M. Laskowski, Patrick Trotzke, Kathina Ali, Daniel B Fassnacht, Martina de Zwaan, Matthias Brand, Michael Häder and Michael Kyrios has been published in the Journal of Behavioral Addictions, DOI: 10.1556/2006.2021.00013

Polarization and mobilization on social media affect infection figures

Model calculations reveal a link between political dissemination of information and Corona infections in the USA

MAX PLANCK INSTITUTE FOR HUMAN DEVELOPMENT

Research News

 

Measures to contain the Corona pandemic are the subject of politically charged debate and tend to polarize segments of the population. Those who support the measures motivate their acquaintances to follow the rules, while those who oppose them call for resistance in social media. But how exactly do politicization and social mobilization affect the incidence of infection? Researchers at the Max Planck Institute for Human Development have examined this question using the USA as an example. Their findings were published in Applied Network Science.

Limit crowds, keep a safe distance, and wear masks. Such non-pharmaceutical interventions, which should be implemented by everyone if possible in order to contain the incidence of infection, have played a central role since the beginning of the Corona pandemic. These measures have been disseminated via not only traditional media such as newspapers, radio, and television but also social media to a large extent. We can see that the appeals, recommendations, and regulations of governments are not only met with approval and understanding but also stimulate politically charged discussions, polarization, conspiracy narratives, and mobilization against the measures - often mixed with personal opinions.

But what does the rejection of Corona measures depend on? And is there a connection between the politicization of Corona topics in social networks and the development of the infection figures? Researchers at the Max Planck Institute for Human Development have investigated this using a mobilization model based on the example of Facebook in the USA. The subject of the study was a hypothetical political campaign in which the Democratic Party recommends non-pharmaceutical measures to combat the spread of Corona virus.

The results of the model calculations show that the hypothetical Democratic campaign would have spread to Democratic states three times faster than to Republican states. No matter in which direction, this political polarization makes it difficult to reach most segments of the population equally. "Accordingly, the acceptance and further dissemination of measures depends on whether the sender and receiver are politically like-minded," says Inho Hong, lead author of the study and a research grant holder in the Center for Humans and Machines at the Max Planck Institute for Human Development.

The researchers then examined the relationship between social mobilization and the actual spread of COVID-19 cases in the USA. They found that, on one hand, mobilization can have a positive effect on pandemic response when large numbers of people join together online to support the regulations by disseminating them quickly and early. On the other hand, there are indications that the political charge and resulting actions may have exacerbated the incidence of infection in some geographies. For example, infection rates spiked starting in mid-April 2020 after Republicans demonstrated against the first lockdown and did not consistently comply with the specified hygiene rules. This means that political regulations such as lockdowns can have the opposite effect after they are reinterpreted by politically polarized opponents - and even exacerbate the situation.

The researchers used a mobilization model to simulate the processes of social mobilization. The data for this came from two sources: The "Facebook Social Connectedness Index", a measure for calculating social connections between people from different regions, and demographic information and data sets from election protocols of the New York Times. Based on this data, the researchers calculated how the Democratic campaign would have spread via Facebook and whether it would have led to political actions such as demonstrations.

In previous studies, researchers have used this mobilization model to examine how political actions have formed and spread on social networks in the USA. "The model has allowed us to show a link between the social divide in the USA, the spread of information via Facebook, and the evolution of the incidence of infection," says Alex Rutherford, senior research scientist and principal investigator with the Center for Humans and Machines at the Max Planck Institute for Human Development and co-author of the study.

The study results show that a political charging of the measures to combat the pandemic can have a counterproductive effect and even fuel the incidence of infection. "On social media, the mask was quickly re-interpreted as a political statement and used to polarize the population. Governments should therefore consider to whom and through which channels they disseminate information and whether they want to target mobilization," says Manuel Cebrian, Leader of the Digital Mobilization Research Group at the Center for Humans and Machines at the Max Planck Institute for Human Development and co-author of the study.

The focus of the study was on political attitudes of US citizens. Other possibly decisive social factors such as occupation, income, gender, and origin would have to be investigated in further studies. These could provide information for planning the communication of future measures - for example, government vaccination strategies.

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Max Planck Institute for Human Development

The Max Planck Institute for Human Development in Berlin was founded in 1963. It is an interdisciplinary research institution dedicated to the study of human development and education. The Institute belongs to the Max Planck Society for the Advancement of Science, one of the leading organizations for basic research in Europe.

Original investigation: When drug companies raise list prices, out-of-pocket costs for patients

When drug manufacturers raise the list price for brand-name prescription drugs, do patients' out-of-pocket costs rise too?

BRIGHAM AND WOMEN'S HOSPITAL

Research News

 

WHO Benjamin Rome, MD, Instructor of Medicine at Harvard Medical School and researcher in the Program On Regulation, Therapeutics, And Law (PORTAL) in the Division of Pharmacoepidemiology and Pharmacoeconomics, Brigham and Women's Hospital; corresponding author of a paper published in JAMA Network Open.

WHAT When drug manufacturers raise the list price for brand-name prescription drugs, do patients' out-of-pocket costs rise too? A new study published in JAMA Network Open by Dr. Benjamin Rome and colleagues in the Brigham's Division of Pharmacoepidemiology and Pharmacoeconomics finds that more than half of patients may experience increases in out-of-pocket spending when drug prices increase.

Rome and co-authors studied 79 brand-name drugs and found that the "list price" charged by drug manufacturers increased 16.7 percent, the "net price" (after manufacturer rebates) by 5.4 percent, and average out-of-pocket costs by 3.5 percent from 2015 to 2017. Some commercially insured patients who pay only prescription drug copayments were insulated from the increase in drug's list prices, but patients with coinsurance or deductibles experienced out-of-pocket spending increases of 15 percent over this time, corresponding with the changes in prices. Among these patients, researchers found no evidence that manufacturer rebates offset out-of-pocket expenses.

"The exorbitant and unregulated prices set by drug manufacturers affect how much patients pay," said Rome. "Pharmaceutical companies often argue that the high list prices for their medicines are not important, but we found that many patients are responsible for coinsurance or deductibles, which exposes them to the annual price hikes that are common practice by many pharmaceutical companies."

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POST-SCARCITY ANARCHISM

BEFORE ECO SOCIALISM OR ECO MARXISM THERE WAS BOOKCHIN'S SOCIAL ECOLOGY

https://libcom.org/files/Bookchin-Murray-Post-Scarcity-Anarchism-1986.pdf

 

MARXISM AND ECOLOGICAL ECONOMICS

TOWARD A RED AND GREEN POLITICAL ECONOMY

PAUL BURKETT

HISTORICAL MATERIALISM #11 

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 https://www.academia.edu/32106183/_Paul_Burkett_Marxism_and_Ecological_Economics_T_BookZZ_org_

KARL MARX ON TECHNOLOGY AND ALIENATION BOOK PDF

 https://www.academia.edu/35611406/Karl_Marx_on_Technology_and_Alienation_pdf

 

Cellphone converts into powerful chemical detector

With only $50 worth of components, an ordinary cellphone transforms into a sophisticated scientific instrument, capable of identifying chemicals, drugs, and pathogens

AMERICAN INSTITUTE OF PHYSICS

Research News

 

IMAGE: PHOTO SHOWING RELATIVE SIZE OF SPECTROMETER (LEFT) AND CELLPHONE (RIGHT AND AT THE LOWER END OF THE SPECTROMETER). view more 

CREDIT: PETER RENTZEPIS

WASHINGTON, May 4, 2021 -- Scientists from Texas A&M have developed an extension to an ordinary cellphone that turns it into an instrument capable of detecting chemicals, drugs, biological molecules, and pathogens. The advance is reported in Reviews of Scientific Instruments, by AIP Publishing.

Modern cellphones include high-quality cameras capable of detecting low levels of light and eliminating digital noise through software processing of the captured images. Recent work has taken advantage of this sensitivity to produce cellphone cameras that can be used as portable microscopes and heart rate detectors.

The current advance is based on two types of spectroscopy. One type, known as fluorescence spectroscopy, measures the fluorescent light emitted by a sample. Another, known as Raman spectroscopy, is useful for detecting molecules, such as DNA and RNA, that do not fluoresce or emit light at very low intensities. Both types were used to develop this cellphone detector.

The system includes an inexpensive diode laser as a light source, oriented at right angles to the line connecting the sample and the cellphone camera. The right-angle arrangement prevents back reflected light from entering the camera.

"In addition, this right-angle excitation geometry has the advantage of being easier to use for the analysis of samples where a bulk property is to be measured," said author Peter Rentzepis.

The investigators studied a variety of samples using their constructed cellphone detector, including common solvents such as ethanol, acetone, isopropyl alcohol, and methanol. They recorded the Raman spectra of solid objects, including a carrot and a pellet of bacteria.

Carrots were chosen for this study because they contain the pigment carotene. The laser light used in their system has a wavelength that is easily absorbed by this orange pigment and by pigments in the bacteria.

The investigators compared the sensitivity of their system to the most sensitive industrial Raman spectrometers available. The ratio of signal to noise for the commercial instrument was about 10 times higher than the cellphone system.

The sensitivity of the cellphone detector could, however, be doubled by using a single RGB channel for analysis. The system has a rather limited dynamic range, but the investigators note that this problem can be easily overcome through several HDR, or High Dynamic Range, applications that combine images from multiple exposures.

The additional components, including the laser, add a cost of only about $50 to the price of a typical cellphone, making this system an inexpensive but accurate tool for detecting chemicals and pathogens in the field.

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The article "Cell-phone camera Raman spectrometer" is authored by Dinesh Dhankhar, Anushka Nagpal, and Peter M. Rentzepis. The article will appear in Review of Scientific Instruments on May 4, 2021 (DOI: 10.1063/5.0046281). After that date, it can be accessed at https://aip.scitation.org/doi/10.1063/5.0046281.

ABOUT THE JOURNAL

Review of Scientific Instruments publishes novel advancements in scientific instrumentation, apparatuses, techniques of experimental measurement, and related mathematical analysis. Its content includes publication on instruments covering all areas of science including physics, chemistry, materials science, and biology. See https://aip.scitation.org/journal/rsi.