One simple vitamin can reduce your risk of heart disease.
“一种简单的维生素 即可降低患心脏病的风险”,
Eating chocolate reduces stress in students.
“吃巧克力可为学生减压”,
New drug prolongs lives of patients with rare disease.
“新药延长了罕见病患者寿命”,
Health headlines like these are published every day, sometimes making opposite claims from each other. There can be a disconnect between broad, attention-grabbing headlines and the often specific, incremental results of the medical research they cover. So how can you avoid being misled by grabby headlines?
类似的健康标题每天都在发表, 有时提出相互矛盾的主张。 宽泛且引人注目的头条新闻, 与涵盖的具体医学研究结果之间 可能存在脱节。 那么,如何避免被“标题党”误导呢?
The best way to assess a headline’s credibility is to look at the original research it reports on. We’ve come up with a hypothetical research scenario for each of these three headlines.
评估标题可信度的最佳方式 是查看原始研究报告。 我们为每一个头条新闻 构思了假设的研究场景,
Keep watching for the explanation of the first example; then pause at the headline to answer the question. These are simplified scenarios. A real study would detail many more factors and how it accounted for them, but for the purposes of this exercise, assume all the information you need is included.
先查看第一个例子的解释, 然后在标题处暂停,回答问题。 这是简化的流程, 真正的研究会详细说明 多种因素及其影响。 但就本练习而言, 假设已包含需要的所有信息。
Let’s start by considering the cardiovascular effects of a certain vitamin, Healthium. The study finds that participants taking Healthium had a higher level of healthy cholesterol than those taking a placebo. Their levels became similar to those of people with naturally high levels of this kind of cholesterol. Previous research has shown that people with naturally high levels of healthy cholesterol have lower rates of heart disease.
让我们首先思考 一种维生素 Healthium 对心血管的影响。 该研究发现, 服用 Healthium 的参与者 相较于服用安慰剂的人 健康胆固醇指标更高。 他们的该项指标 与天生健康胆固醇高的人 指标一样。 以前的研究表明, 健康胆固醇水平高的人 患心脏病的几率较低。
So what makes this headline misleading: "Healthium reduces risk of heart disease."
“Healthium 可降低患心脏病的风险”, 此标题产生误导的根源是什么呢?
The problem with this headline is that the research didn’t actually investigate whether Healthium reduces heart disease. It only measured Healthium’s impact on levels of a particular kind of cholesterol. The fact that people with naturally high levels of that cholesterol have lower risk of heart attacks doesn’t mean that the same will be true of people who elevate their cholesterol levels using Healthium.
此标题的问题在于, 该研究实际上没有调查 Healthium 是否可降低心脏病。 它只测量了 Healthium 对某种胆固醇水平的影响。 该胆固醇天生水平高的人 心脏病发作的风险较低, 并不意味着 用 Healthium 提高胆固醇水平的人也如此。
Now that you’ve cracked the case of Healthium, try your hand at a particularly alluring mystery: the relationship between eating chocolate and stress. This hypothetical study recruits ten students. Half begin consuming a daily dose of chocolate, while half abstain. As classmates, they all follow the same schedule. By the end of the study, the chocolate eaters are less stressed than their chocolate-free counterparts.
现在你已经破解了 Healthium 的案例, 试着破解一个特别诱人的谜题吧: “吃巧克力和压力之间的关系”。 这项假设的研究招募了十名学生。 一半人开始每天吃一定量的巧克力, 而另一半没有吃。 他们同班,所以时间表也相同。 研究结束时,巧克力食用者 相较于未食用者压力较小。
What’s wrong with this headline: "Eating chocolate reduces stress in students"
“吃巧克力可减少学生压力”, 此标题的问题是什么呢?
It’s a stretch to draw a conclusion about students in general from a sample of ten. That’s because the fewer participants are in a random sample, the less likely it is that the sample will closely represent the target population as a whole. For example, if the broader population of students is half male and half female, the chance of drawing a sample of 10 that’s skewed 70% male and 30% is about 12%. In a sample of 100 that would be less than a .0025% chance, and for a sample of 1000, the odds are less than 6 x 10^-36.
从十个样本中得出关于一般 学生的结论是牵强附会的。 因为随机选取样本的人数越少, 样本就越不能代表 整体的目标人群。 例如,更广泛的学生群体 是一半男生一半女生, 抽 10 人的样本, 其中 70% 男生 30% 女生 概率约为 12%。 100 人的样本中, 则概率小于 0.0025%, 对于 1000 的样本, 其概率小于 6 x 10 ^ -36。
Similarly, with fewer participants, each individual’s outcome has a larger impact on the overall results— and can therefore skew big-picture trends. Still, there are a lot of good reasons for scientists to run small studies. By starting with a small sample, they can evaluate whether the results are promising enough to run a more comprehensive, expensive study. And some research requires very specific participants that may be impossible to recruit in large numbers. The key is reproducibility— if an article draws a conclusion from one small study, that conclusion may be suspect— but if it’s based on many studies that have found similar results, it’s more credible.
同样,由于参与者较少, 个人结果对整体结果影响较大—— 因此会扭曲大局趋势。 不过,仍有很多好的理由 支持科学家们进行小型研究。 以小样本开始, 他们能评估结果是否有希望 进行更全面、昂贵的研究。 有些研究需要特殊参与者, 可能无法大量招募。 关键在于可重复性—— 如果一篇文章从一项 小型研究中得出结论, 结论也许是可疑的—— 但如果它从许多研究中 都得到类似结论, 结论便更可信。
We’ve still got one more puzzle. In this scenario, a study tests a new drug for a rare, fatal disease. In a sample of 2,000 patients, the ones who start taking the drug upon diagnosis live longer than those who take the placebo.
我们还剩一个难题, 此案例中,一项研究测试了一种 治疗罕见致命疾病的新药。 2000 名患者的样本中, 被诊断患病并开始服用该药的人 比服用安慰剂的人活得久。
This time, the question is slightly different. What’s one more thing you’d like to know before deciding if the headline, "New drug prolongs lives of patients with rare disease", is justified?
这一次,问题略有不同。 在判断标题“新药延长了罕见疾病 患者的生命”是否恰当之前, 你还要再清楚一件什么事呢?
Before making this call, you’d want to know how much the drug prolonged the patients’ lives. Sometimes, a study can have results that, while scientifically valid, don’t have much bearing on real world outcomes. For example, one real-life clinical trial of a pancreatic cancer drug found an increase in life expectancy— of ten days.
做这个决定之前, 你想知道用药 对病人生命药延长多久。 有时,一项研究结果 虽然科学上讲是有效的, 但对现实世界的结果影响不大。 例如,一项胰腺癌药物的 现实临床试验发现, 预期寿命增加了 10 天。
The next time you see a surprising medical headline, take a look at the science it’s reporting on. Even when full papers aren’t available without a fee, you can often find summaries of experimental design and results in freely available abstracts, or even within the text of a news article. It’s exciting to see scientific research covered in the news, and important to understand the studies’ findings.
当你下次看到令人惊讶的医学标题, 看看它报道的科学性。 即使没有免费提供完整的论文, 也可以在免费摘要中 找到实验设计概要和实验结果, 甚至在新闻文本中也能找到。 看到新闻报道的科学研究令人兴奋, 但理解研究结果也很重要。