Health

Study Finds AI Models Fall Short in Early Medical Diagnosis

Published

3 months ago

April 14, 2026

A new study has found that artificial intelligence language models still struggle with one of the most critical aspects of medical care, raising concerns about their use without human oversight.

Researchers from Mass General Brigham reported that AI systems failed to produce an appropriate early diagnosis more than 80 per cent of the time. The findings, published in JAMA Network Open, highlight ongoing limitations in how these systems reason through complex clinical scenarios.

The study examined 21 large language models, including systems developed by OpenAI, Google and xAI. Among those tested were versions of GPT, Gemini, Claude, Grok and DeepSeek.

Researchers used a structured evaluation tool known as PrIME-LLM to assess how well the models handled different stages of clinical reasoning. These stages included forming an initial diagnosis, ordering tests, reaching a final diagnosis and planning treatment. The models were tested using 29 standardised clinical scenarios, with information introduced gradually to mirror real-life patient cases.

While the systems showed relatively strong performance when identifying a final diagnosis, their ability to generate a differential diagnosis — a key step in distinguishing between conditions with similar symptoms — remained limited. This early-stage reasoning is widely regarded as essential in medical decision-making.

Marc Succi, a co-author of the study, said current models are not ready for independent clinical use. He noted that differential diagnosis represents a core part of medical practice that AI has yet to replicate effectively.

Another researcher, Arya Rao, said the findings show that AI performs best when given complete information but struggles when cases are still developing. She explained that the models are less reliable in situations where doctors must make judgments based on limited or uncertain data.

Despite these shortcomings, the study identified a group of higher-performing systems, including advanced versions of GPT, Gemini, Claude and Grok. These models achieved final diagnosis success rates ranging from around 60 per cent to over 90 per cent when provided with detailed clinical data such as lab results and imaging.

Experts not involved in the research also stressed the importance of caution. Susana Manso García said the findings reinforce that AI should not replace professional medical judgement. She advised that patients continue to seek guidance from qualified healthcare providers when dealing with health concerns.

The study concludes that while AI has made progress, it still requires close human supervision in clinical settings. Researchers say the technology shows promise as a support tool, but its current limitations mean it cannot yet be trusted to make independent medical decisions.

Health

Study Finds Men Far More Likely Than Women to ‘Hit the Wall’ in Marathons

Published

3 days ago

July 4, 2026

Web Reporter

Men are significantly more likely than women to experience the dreaded marathon phenomenon known as “hitting the wall,” according to a large international study that analysed the performances of more than 870,000 runners over a 26-year period.

The research, published in the journal Scientific Reports, examined the results of 873,334 finishers in the Berlin Marathon between 1999 and 2025. Researchers found that although men generally complete marathons faster than women, they are much more likely to suffer a dramatic slowdown during the later stages of the race because of less consistent pacing.

According to the study, men are almost twice as likely overall to experience a sudden decline in speed during a marathon. In some performance categories, they were found to be up to six times more likely than women to “hit the wall,” a term commonly used to describe severe physical exhaustion caused by depleted energy stores.

Researchers said the findings point to differences in race strategy rather than physical ability alone. Men were more likely to begin races at an aggressive pace, increasing the risk of fatigue before reaching the finish line.

The study concluded that “men, regardless of performance level, are more prone to aggressive pacing and catastrophic deceleration.” The authors suggested that greater willingness to take risks and higher levels of confidence may encourage many male runners to start faster than they can realistically sustain over the full 42.195-kilometre distance.

Women, on the other hand, displayed more controlled pacing throughout the race. Researchers found they were better at regulating their effort from start to finish, reducing the likelihood of a significant loss of speed during the closing kilometres.

The report described women as showing “superior self-pacing abilities and greater resistance to decision-making fatigue,” characteristics that can be particularly valuable during endurance events.

Maintaining a steady pace is widely regarded as one of the most important factors in marathon performance. Running too quickly during the opening stages can rapidly consume the body’s glycogen reserves, leaving athletes without enough energy to sustain their speed in the final part of the race.

The researchers noted that pacing is “the most critical tactical determinant of performance” in marathon running, making strategic decision-making just as important as physical fitness.

The findings could influence how coaches and runners prepare for long-distance races. Rather than focusing solely on speed, the study suggests that adopting a realistic race plan and maintaining a consistent pace throughout the event may improve overall performance and reduce the chances of a late-race collapse.

With marathon participation continuing to grow worldwide, the researchers believe a better understanding of pacing strategies could help runners of all abilities achieve stronger and more consistent results.

Health

Study Links Higher Coffee Consumption to Lower Risk of Liver Disease

Published

5 days ago

July 3, 2026

Web Reporter

Regular coffee consumption may help reduce the risk of serious liver diseases, including cirrhosis, liver cancer and liver-related deaths, according to a new study published in the journal Clinical Gastroenterology and Hepatology.

The research found that people who consumed higher amounts of coffee, including decaffeinated varieties, were less likely to develop chronic liver conditions than those who drank little or no coffee. The findings add to growing evidence that coffee may play a role in supporting long-term liver health, although researchers stressed that the results do not prove a direct cause-and-effect relationship.

The study examined data from more than 350,000 participants enrolled in the UK Biobank, one of the world’s largest long-term health research projects. None of the participants had cirrhosis or liver cancer at the beginning of the study. Researchers monitored their health over a period of 13 years to assess how coffee consumption affected liver-related outcomes.

According to the findings, participants who drank five or more cups of coffee each day had a 32 percent lower risk of developing cirrhosis than those who consumed little or no coffee. They also recorded a 47 percent lower risk of liver cancer and a 42 percent reduction in deaths linked to liver disease.

Researchers found additional indicators of improved liver health among regular coffee drinkers. Participants with higher coffee intake showed lower levels of liver fat, liver iron, fibrosis and inflammation. Blood tests also revealed increased levels of proteins associated with healthy liver function, while markers linked to liver scarring and inflammation were generally lower.

The findings come as liver disease continues to pose a major global health challenge. A separate study published in 2023 estimated that liver disease causes around two million deaths each year, accounting for about four percent of all deaths worldwide. Men account for nearly two-thirds of those fatalities.

Despite the encouraging results, the researchers urged caution in interpreting the findings. Senior study author Ju Dong Yang said moderate coffee consumption appears to be beneficial for people who already enjoy drinking coffee and tolerate it well.

“Our findings support moderate coffee consumption for people who already enjoy and tolerate it well,” Yang said.

He added that the study does not provide sufficient evidence to recommend that people who do not currently drink coffee should begin doing so solely to reduce their risk of liver disease.

Health experts continue to advise that maintaining a healthy weight, limiting alcohol consumption, eating a balanced diet and managing conditions such as obesity and diabetes remain the most effective ways to reduce the risk of chronic liver disease. Researchers said additional studies are needed to better understand which compounds in coffee may contribute to its potential protective effects.

Health

Lancet Review Finds mRNA Vaccines Safe and Highly Effective, Calls for Wider Global Access

Published

6 days ago

July 1, 2026

Web Reporter

A comprehensive review of data covering billions of administered doses of mRNA vaccines has concluded that the technology remains both safe and highly effective in preventing infectious diseases, with researchers urging governments and health organisations to focus on expanding global access.

The review, published in The Lancet, examined evidence gathered since mRNA vaccines were first deployed on a large scale during the COVID-19 pandemic. Researchers found that the vaccines continue to provide strong protection against severe illness while serious side effects remain uncommon.

Unlike conventional vaccines, mRNA vaccines work by delivering genetic instructions that enable the body’s cells to produce a harmless viral protein. This process trains the immune system to recognise and respond to future infections without altering a person’s DNA.

According to the review, mRNA vaccines were 87% effective in preventing confirmed SARS-CoV-2 infections within 14 to 42 days after vaccination. The vaccines also demonstrated 93% effectiveness in preventing hospital admissions and 94% effectiveness in preventing deaths related to COVID-19 during the same period.

Researchers noted that immunity declines over time, but booster doses restore a significant portion of the lost protection.

The review also assessed vaccine safety across billions of administered doses. It found that serious adverse events, including myocarditis, pericarditis and anaphylaxis, occurred very rarely. Most reported reactions, such as pain at the injection site, fatigue and fever, were mild to moderate and typically resolved within a few days.

“Across billions of administered doses, serious adverse events have been rare, well characterised, and consistently outweighed by the substantial protection conferred against severe disease, hospitalisation, and death,” the researchers wrote.

The review concluded that the vaccines have proven effective across a broad range of populations, including children, older adults, pregnant women and people with weakened immune systems.

Researchers also highlighted the growing potential of mRNA technology beyond infectious diseases. They said ongoing research could lead to personalised cancer vaccines designed to match an individual patient’s tumour characteristics, opening new possibilities for targeted treatment.

Co-author Manish Sadarangani of the University of British Columbia and BC Children’s Hospital Research Institute said mRNA vaccines have already changed how the world responds to emerging infectious diseases and could continue to play an important role in preventive medicine and cancer care.

The review also noted that improvements in vaccine storage, including higher-temperature storage methods and freeze-drying technologies, could simplify transportation, reduce waste and improve access in remote regions.

Despite these advances, the researchers stressed that manufacturing capacity and equitable distribution remain major challenges. They called for greater investment in local production, technology transfer and stronger regulatory systems, particularly in low- and middle-income countries.

Co-author Robin Shattock of Imperial College London said expanding manufacturing networks and strengthening regional production capabilities would shorten supply chains, lower costs and help ensure countries have faster access to vaccines during future global health emergencies.