Critical thinking

Look for the Missing Comparison

Claims about improvement, speed, quality, and effectiveness need meaningful baselines.

Claims about improvement, speed, quality, and effectiveness need meaningful baselines. An impressive result may answer a different question from the decision you face. Identifying the comparison helps you interpret evidence and design better trials in your own learning.

Find the implied baseline

Underline words such as better, faster, and more effective. Ask better than what? A course may report improvement after instruction, while improvement could also follow independent practice, another course, or repeated test exposure. The result can remain informative while answering a narrower question than a comparison among methods. Write that narrower question explicitly before adopting the broader promotional interpretation of what the course has demonstrated.

Check fairness

Compare starting skill, task difficulty, time, and measurement. Your hardest practice set this week cannot be directly compared with the easiest set last week to isolate growth. At work, notice changing tools, staffing, and workload. Imperfect comparisons can guide choices if limits are explicit. Pretending relevant conditions were controlled produces false confidence and obscures why later results differ from expectations. Identify the differences most likely to influence the outcome.

Use a realistic alternative

Compare an intervention with what you would otherwise do. When choosing a course, that alternative matters more than doing absolutely nothing if inaction is not realistic. Beginners can add a baseline question beside comparative claims. Advanced readers can ask whether the comparison was chosen before results were known and whether another reasonable baseline changes interpretation. A good baseline clarifies options instead of merely making one proposal appear impressive.

Put it into practice

Put it into practice

  1. Choose an improvement claim.
  2. Identify stated and implied comparisons.
  3. Design a fairer baseline for your actual decision, naming one factor to keep similar and one remaining difference that would still limit the resulting conclusion.
Take this with youAn improvement claim is useful when its baseline matches the question and the alternatives actually available.

Sources & further reading

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