Evaluate Scientific
Conclusions

Learn to judge whether a conclusion is truly supported by the evidence — a core skill for the GED Science test.

GED Science

What Is a Conclusion?

A conclusion is a statement that explains what the data means. It is the interpretation a scientist draws after collecting and analyzing evidence (the data, measurements, and observations).

Evidence Supports the Claim

Why This Skill Matters

On the GED Test

Many questions ask if a conclusion is supported, partly supported, or contradicted by a passage or graph.

In Daily Life

Headlines and ads make claims. Knowing if evidence backs them up protects you from being misled.

In Science

Good science separates what the data shows from what we wish it showed.

The Core Rule

Think of it as a balance. The conclusion can only "weigh" as much as the evidence holds up. If the claim says more than the data shows, it is not supported.

Supported vs Unsupported

Suppose a study finds that plants given fertilizer grew taller than plants without it.

✓ Supported

"Fertilizer increased plant height in this experiment." (Matches the data exactly.)

✕ Unsupported

"Fertilizer makes all living things grow." (Goes far beyond the evidence.)

Correlation vs Causation

Two things changing together (correlation) does not prove one causes the other (causation). A conclusion claiming cause needs a controlled experiment.

A 4-Step Method

1

Find the conclusion. Identify exactly what claim is being made.

2

Find the evidence. List the data, results, or observations given.

3

Compare. Does each part of the claim match the evidence?

4

Judge. Decide: fully supported, partly supported, or unsupported.

Worked Example 1

Data: In a survey, students who slept 8+ hours scored an average of 85% on a test, while those sleeping under 6 hours averaged 72%.

Worked Example 2

Using the same survey data, a student writes a new conclusion. Let us evaluate it.

The survey only shows a correlation. It did not control other factors (study habits, diet, stress). It also measures test scores, not "smartness." The claim overreaches on both counts.

Worked Example 3

Experiment: 100 identical seedlings were split into two groups. One got 6 hours of light daily, the other got 12. After 3 weeks, the 12-hour group was taller. All else was kept equal.

Common Mistakes

✕ Overreaching

Claiming more than the data shows ("all," "always," "proves").

✕ Cause from Correlation

Saying one thing causes another based only on them changing together.

✕ Ignoring Evidence

Accepting a conclusion that contradicts the actual data given.

✕ Adding Outside Beliefs

Using personal opinion instead of the evidence in the passage.

Quick Reference

	Supported	Unsupported
Matches data?	Yes, exactly	No, goes beyond
Claim strength	Cautious words	"All," "proves"
Cause claims	Only from experiments	From mere correlation
Outside opinion	None added	Relies on belief

Before You Practice

1

A conclusion must be directly backed by the evidence.

2

Beware overreaching words: all, always, proves, never.

3

Correlation is not causation — cause needs a controlled experiment.

Question 1 of 5

A study found that people who drink coffee daily also tend to exercise more. Which conclusion is best supported?

The study only shows the two behaviors occur together (correlation). It cannot prove cause in either direction, and "everyone" overreaches.

Question 2 of 5

An experiment showed a new fertilizer increased tomato yield by 15% compared to a control group, with all else equal. Which conclusion is unsupported?

The experiment only tested tomatoes. Claiming it works for "every crop on Earth" goes far beyond the evidence — it overreaches.

Question 3 of 5

A graph shows ice cream sales and shark attacks both peak in July. What is the most accurate conclusion?

A third factor — warm weather — drives both. The data only shows they move together, so only a correlation can be claimed.

Question 4 of 5

A researcher gave 200 identical plants the same water, soil, and light. Half received Music Type A played for 4 hours daily; the other half received silence. After 6 weeks, the music group was 2 cm taller on average. All other conditions were kept the same throughout the study.

▼ Tap to read passage

Which conclusion does the evidence best support?

This was a controlled experiment, so the supported conclusion describes exactly what was measured: the music group grew taller in this study. The others add feelings, "all/forever," or untested comparisons.

Question 5 of 5

A passage reports: "Of 50 patients given the medicine, 30 felt better." There was no control group. Which conclusion is best?

Without a control group, patients might have improved on their own. The supported conclusion notes the result honestly while flagging that cause cannot be confirmed.

Evaluate ScientificConclusions

What Is a Conclusion?

Evidence Supports the Claim

Why This Skill Matters

The Core Rule

Supported vs Unsupported

Correlation vs Causation

A 4-Step Method

Worked Example 1

Worked Example 2

Worked Example 3

Common Mistakes

Quick Reference

Before You Practice

Question 1 of 5

Question 2 of 5

Question 3 of 5

Question 4 of 5

Question 5 of 5

You Can Now Evaluate Conclusions

Evaluate Scientific
Conclusions