What are best practices for investigating statistical claims?

When evaluating statistical claims, it’s essential to approach them with a critical and curious mindset. Here are some strategies you can use to assess statistical information in everyday situations: 

  1. Ask questions: Start by asking yourself a few key questions about the claim. Who is making the claim? What is their objective? Are they trying to persuade or sell something? Reflecting on these questions can help you gauge the credibility of the claim.
  2. Verify sources: Check the source of the information. Is it a reliable organization or an individual with expertise in the subject? Reputable sources tend to be more accurate and trustworthy.
  3. Fact-check: Cross-reference the claim with other sources to ensure its accuracy. Look for any inconsistencies or discrepancies that may indicate a misrepresentation of the facts.
  4. Look for alternative sources: Seek out multiple perspectives on the topic. This will provide you with a broader understanding of the issue and help you identify any biases in the original claim.
  5. Verify the sample size: A larger sample size typically leads to more accurate and generalizable conclusions. For example, a survey of 1,000 people is more likely to represent the general population than a survey of 20 people.
  6. Examine the methodology: Consider how the data was collected and analyzed. Was the methodology appropriate for answering the research question? Were there any potential biases or limitations? For instance, if a study claims that a new exercise program leads to significant weight loss, but the participants self-reported their weight, the results may be less reliable due to potential inaccuracies in self-reporting.
  7. Check for statistical significance: Statistical significance helps determine if the results are likely due to chance or a genuine effect. If a study finds a statistically significant difference between two groups, it means the difference is probably not due to random chance.
  8. Understand the context: Consider the broader context of the claim. How does it fit within existing knowledge or research? Are there any relevant external factors that might influence the results? For example, a study that claims a specific diet leads to weight loss might not account for other factors like exercise, genetics, or socioeconomic status.
  9. Be cautious with correlations: Correlation does not imply causation. Just because two variables are related does not mean one causes the other. For instance, ice cream sales and drowning incidents might be correlated, but this doesn’t mean that eating ice cream causes drowning. Instead, both might be related to the fact that they happen more frequently during the summer months.
  10. Consider practical significance: Even if a result is statistically significant, it may not be practically significant. For example, a medication that reduces headache severity by 0.5% might be statistically significant but not very meaningful for those suffering from severe headaches. 

By using these strategies and maintaining a critical mindset, you’ll be better equipped to evaluate the validity of statistical claims and make informed decisions based on the information presented to you.