Thus far, genome-wide association studies (GWAS) have been disappointing in the inability of investigators to use the results of identified, statistically significant variants in complex diseases to make predictions useful for personalized medicine. Why are significant variables not leading to good prediction of outcomes? We point out that this problem is prevalent in simple as well as complex data, in the sciences as well as the social sciences. We offer a brief explanation and some statistical insights on why higher significance cannot automatically imply stronger predictivity and illustrate through simulations and a real breast cancer example. We also demonstrate that highly predictive variables do not necessarily appear as highly significant, thus evading the researcher using significance-based methods. We point out that what makes variables good for prediction versus significance depends on different properties of the underlying distributions. If prediction is the goal, we must lay aside significance as the only selection standard. We suggest that progress in prediction requires efforts toward a new research agenda of searching for a novel criterion to retrieve highly predictive variables rather than highly significant variables. We offer an alternative approach that was not designed for significance, the partition retention method, which was very effective predicting on a long-studied breast cancer data set, by reducing the classification error rate from 30% to 8%.

Understanding the mortality impact of COVID-19 requires not only counting the dead, but analyzing how premature the deaths are. We calculate years of life lost (YLL) across 81 countries due to COVID-19 attributable deaths, and also conduct an analysis based on estimated excess deaths. We find that over 20.5 million years of life have been lost to COVID-19 globally. As of January 6, 2021, YLL in heavily affected countries are 2–9 times the average seasonal influenza; three quarters of the YLL result from deaths in ages below 75 and almost a third from deaths below 55; and men have lost 45% more life years than women. The results confirm the large mortality impact of COVID-19 among the elderly. They also call for heightened awareness in devising policies that protect vulnerable demographics losing the largest number of life-years.

Social scientists have shown how easily individuals are moved to exclude outgroup members. Can we foster inclusion instead? This study leverages one of the most significant humanitarian crises of our time to test whether, and under what conditions, American citizens adopt more inclusionary behavior toward Syrian refugees. We conduct a nationally representative survey of over 5,000 American citizens in the weeks leading up to the 2016 presidential election and experimentally test whether a perspective-taking exercise increases inclusionary behavior in the form of an anonymous letter supportive of refugees to be sent to the 45th President of the United States. Our results indicate that the perspective-taking message increases the likelihood of writing such a positive letter by two to five percentage points. By contrast, an informational message had no significant effect on letter writing. The effect of the perspective-taking exercise occurs in the short run only, manifests as a behavioral rather than an attitudinal response, and is strongest among Democrats. However, this effect also appears in the subset of Republican respondents, suggesting that efforts to promote perspective taking may move to action a wide cross-section of individuals.

What types of refugees do Americans prefer for admission into the United States? Scholars have explored the immigrant characteristics that appeal to Americans and the characteristics that Europeans prioritize in asylum-seekers, but we currently do not know which refugee characteristics Americans prefer. We conduct a conjoint experiment on a representative sample of 1800 US adults, manipulating refugee attributes in pairs of Syrian refugee profiles, and ask respondents to rate each refugee’s appeal. Our focus on Syrian refugees in a 2016 survey experiment allows us to speak to the concurrent refugee crisis on the eve of a polarizing election, while also identifying religious discrimination, holding constant the refugee’s national origin. We find that Americans prefer Syrian refugees who are female, high-skilled, English-speaking, and Christian, suggesting they prioritize refugee integration into the U.S. labor and cultural markets. We find that the preference for female refugees is not driven by the desire to exclude Muslim male refugees, casting doubt that American preferences at the time were motivated by security concerns. Finally, we find that anti-Muslim bias in refugee preferences varies in magnitude across key subgroups, though it prevails across all sample demographics.

Scrub typhus, a potentially fatal infection caused by the pathogen Orientia tsutsugamushi, has a wide geographical distribution. This systematic review analyses the evidence from prospective controlled clinical studies for the efficacy of antibiotics in the treatment of scrub typhus. PubMed, Embase, Scopus, Cochrane Library, CINAHL and clinical trial registries in China, India and Sri Lanka were searched for controlled prospective clinical trials (randomized, quasi-randomized or non-randomized) enrolling patients with confirmed scrub typhus for treatment with antibiotics. The PROSPERO registration number for this review is CRD42017071374. Eleven studies (from Southeast Asia and China) that enrolled 957 patients into 28 study groups met the inclusion criteria. Doxycycline was the most frequent comparator with other antibiotics. Chloramphenicol, tetracycline and azithromycin (limited evidence for roxithromycin, telithromycin, levofloxacin and rifampicin) had equal efficacy to doxycycline in achieving clinical cure. The cure rates in all studies varied from 64 to 100%. Of the antibiotics frequently used in current practice, azithromycin had the best evidence compared with doxycycline for equal efficacy in clinical cure (three trials, 280 participants, moderate quality evidence) with fewer gastrointestinal adverse events. The preferred choice of antibiotics for each patient depends on the adverse effect profile, personal circumstances (e.g., age, pregnancy), cost and local prescription guidelines.