Discover the most talked about and latest scientific content & concepts.

Concept: Effectiveness


We explore whether the number of null results in large National Heart Lung, and Blood Institute (NHLBI) funded trials has increased over time.

Concepts: Clinical trial, Heart, Effectiveness, Avicenna,, Vein, Pulmonary artery, Null result


The effects of probiotic supplementation on fecal microbiota composition in healthy adults have not been well established. We aimed to provide a systematic review of the potential evidence for an effect of probiotic supplementation on the composition of human fecal microbiota as assessed by high-throughput molecular approaches in randomized controlled trials (RCTs) of healthy adults.

Concepts: Epidemiology, Gut flora, Evidence-based medicine, Systematic review, Randomized controlled trial, Effectiveness, Pharmaceutical industry, Meta-analysis


To determine the effectiveness of tai chi interventions compared with aerobic exercise, a current core standard treatment in patients with fibromyalgia, and to test whether the effectiveness of tai chi depends on its dosage or duration.

Concepts: Clinical trial, Randomized controlled trial, Effectiveness, Efficacy, Strength training, Exercise physiology


Reducing the number of host-vector interactions is an effective way to reduce the spread of vector-borne diseases. Repellents are widely used to protect humans from a variety of protozoans, viruses, and nematodes. DEET (N,N-Diethyl-meta-toluamide), a safe and effective repellent, was developed during World War II. Fear of possible side effects of DEET has created a large market for “natural” DEET-free repellents with a variety of active ingredients. We present a comparative study on the efficacy of eight commercially available products, two fragrances, and a vitamin B patch. The products were tested using a human hand as attractant in a Y-tube olfactometer setup with Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse), both major human disease vectors. We found that Ae. albopictus were generally less attracted to the test subject’s hand compared with Ae, aegypti. Repellents with DEET as active ingredient had a prominent repellency effect over longer times and on both species. Repellents containing p-menthane-3,8-diol produced comparable results but for shorter time periods. Some of the DEET-free products containing citronella or geraniol did not have any significant repellency effect. Interestingly, the perfume we tested had a modest repellency effect early after application, and the vitamin B patch had no effect on either species. This study shows that the different active ingredients in commercially available mosquito repellent products are not equivalent in terms of duration and strength of repellency. Our results suggest that products containing DEET or p-menthane-3,8-diol have long-lasting repellent effects and therefore provide good protection from mosquito-borne diseases.

Concepts: Effectiveness, Mosquito, Aedes aegypti, Aedes, Dengue fever, Insect repellent, Asian tiger mosquito, DEET


Case reports describe persistent erectile dysfunction (PED) associated with exposure to 5α-reductase inhibitors (5α-RIs). Clinical trial reports and the manufacturers' full prescribing information (FPI) for finasteride and dutasteride state that risk of sexual adverse effects is not increased by longer duration of 5α-RI exposure and that sexual adverse effects of 5α-RIs resolve in men who discontinue exposure.

Concepts: Clinical trial, Effectiveness,, Pharmaceutical industry, Adverse drug reaction, Erectile dysfunction, Exposure


The ActiPatch(®) (BioElectronics Corporation, MD, USA) pulsed shortwave therapy device has been shown to be clinically effective in three double-blind randomized controlled pain studies. However, the effectiveness of this device in a broader population of chronic musculoskeletal pain sufferers, affected by a variety of etiologies in different regions of the body, has not been studied.

Concepts: Medicine, Effect, Effectiveness, Pain, Cultural studies, Suffering, Chronic pain, Pain management


Misinformation can undermine a well-functioning democracy. For example, public misconceptions about climate change can lead to lowered acceptance of the reality of climate change and lowered support for mitigation policies. This study experimentally explored the impact of misinformation about climate change and tested several pre-emptive interventions designed to reduce the influence of misinformation. We found that false-balance media coverage (giving contrarian views equal voice with climate scientists) lowered perceived consensus overall, although the effect was greater among free-market supporters. Likewise, misinformation that confuses people about the level of scientific agreement regarding anthropogenic global warming (AGW) had a polarizing effect, with free-market supporters reducing their acceptance of AGW and those with low free-market support increasing their acceptance of AGW. However, we found that inoculating messages that (1) explain the flawed argumentation technique used in the misinformation or that (2) highlight the scientific consensus on climate change were effective in neutralizing those adverse effects of misinformation. We recommend that climate communication messages should take into account ways in which scientific content can be distorted, and include pre-emptive inoculation messages.

Concepts: Carbon dioxide, Effectiveness, Climate change, Theory, Communication, Solar variation, Global warming, Scientific opinion on climate change


Vacant and blighted urban land is a widespread and potentially risky environmental condition encountered by millions of people on a daily basis. About 15% of the land in US cities is deemed vacant or abandoned, an area roughly the size of Switzerland. In a citywide cluster randomized controlled trial, we investigated the effects of standardized, reproducible interventions that restore vacant land on the commission of violence, crime, and the perceptions of fear and safety. Quantitative and ethnographic analyses were included in a mixed-methods approach to more fully test and explicate our findings. A total of 541 randomly sampled vacant lots were randomly assigned into treatment and control study arms; outcomes from police and 445 randomly sampled participants were analyzed over a 38-month study period. Participants living near treated vacant lots reported significantly reduced perceptions of crime (-36.8%,P< 0.05), vandalism (-39.3%,P< 0.05), and safety concerns when going outside their homes (-57.8%,P< 0.05), as well as significantly increased use of outside spaces for relaxing and socializing (75.7%,P< 0.01). Significant reductions in crime overall (-13.3%,P< 0.01), gun violence (-29.1%,P< 0.001), burglary (-21.9%,P< 0.001), and nuisances (-30.3%,P< 0.05) were also found after the treatment of vacant lots in neighborhoods below the poverty line. Blighted and vacant urban land affects people's perceptions of safety, and their actual, physical safety. Restoration of this land can be an effective and scalable infrastructure intervention for gun violence, crime, and fear in urban neighborhoods.

Concepts: Epidemiology, Poverty, Randomized controlled trial, Effectiveness, Sociology, Pharmaceutical industry, Efficacy, Crime


Agitation is a common, challenging symptom affecting large numbers of people with dementia and impacting on quality of life (QoL). There is an urgent need for evidence-based, cost-effective psychosocial interventions to improve these outcomes, particularly in the absence of safe, effective pharmacological therapies. This study aimed to evaluate the efficacy of a person-centred care and psychosocial intervention incorporating an antipsychotic review, WHELD, on QoL, agitation, and antipsychotic use in people with dementia living in nursing homes, and to determine its cost.

Concepts: Life, The Canon of Medicine, Randomized controlled trial, Effectiveness, Quality, Quality of life, Intervention, Impact event


Background A candidate tetravalent dengue vaccine is being assessed in three clinical trials involving more than 35,000 children between the ages of 2 and 16 years in Asian-Pacific and Latin American countries. We report the results of long-term follow-up interim analyses and integrated efficacy analyses. Methods We are assessing the incidence of hospitalization for virologically confirmed dengue as a surrogate safety end point during follow-up in years 3 to 6 of two phase 3 trials, CYD14 and CYD15, and a phase 2b trial, CYD23/57. We estimated vaccine efficacy using pooled data from the first 25 months of CYD14 and CYD15. Results Follow-up data were available for 10,165 of 10,275 participants (99%) in CYD14 and 19,898 of 20,869 participants (95%) in CYD15. Data were available for 3203 of the 4002 participants (80%) in the CYD23 trial included in CYD57. During year 3 in the CYD14, CYD15, and CYD57 trials combined, hospitalization for virologically confirmed dengue occurred in 65 of 22,177 participants in the vaccine group and 39 of 11,089 participants in the control group. Pooled relative risks of hospitalization for dengue were 0.84 (95% confidence interval [CI], 0.56 to 1.24) among all participants, 1.58 (95% CI, 0.83 to 3.02) among those under the age of 9 years, and 0.50 (95% CI, 0.29 to 0.86) among those 9 years of age or older. During year 3, hospitalization for severe dengue, as defined by the independent data monitoring committee criteria, occurred in 18 of 22,177 participants in the vaccine group and 6 of 11,089 participants in the control group. Pooled rates of efficacy for symptomatic dengue during the first 25 months were 60.3% (95% CI, 55.7 to 64.5) for all participants, 65.6% (95% CI, 60.7 to 69.9) for those 9 years of age or older, and 44.6% (95% CI, 31.6 to 55.0) for those younger than 9 years of age. Conclusions Although the unexplained higher incidence of hospitalization for dengue in year 3 among children younger than 9 years of age needs to be carefully monitored during long-term follow-up, the risk among children 2 to 16 years of age was lower in the vaccine group than in the control group. (Funded by Sanofi Pasteur; numbers, NCT00842530 , NCT01983553 , NCT01373281 , and NCT01374516 .).

Concepts: Epidemiology, Clinical trial, Malaria, Medical statistics, Vaccine, Effectiveness,, The Age