ISAT - International Student Admissions Interpreting Scientific Data Questions and Answers

Question 1

A researcher is testing the effectiveness of a new drug on reducing high blood pressure.
One group of participants receives the new drug, while a second group receives a pill that looks identical but contains no active ingredient.
What is the primary purpose of the second group?

Accepted Answer

To act as a control group, providing a baseline to measure the drug's true effect against.

Answer

To increase the total number of participants for greater statistical power.

Answer

To test the side effects of the inactive ingredients used in the pill.

Answer

To ensure that participants in the study have a positive expectation of treatment.

Question 2

A study finds a strong positive correlation between the number of hours students spend in the library per week and their final exam scores. The authors conclude that spending more time in the library causes higher exam scores. Why might this conclusion be flawed?

Accepted Answer

Correlation does not imply causation; another factor, such as a student's level of motivation, could influence both library time and exam scores.

Answer

The study should have been conducted over a longer period.

Answer

The sample size of the study was likely too small to be significant.

Answer

Final exam scores are not a reliable measure of student learning.

Question 3

The table below shows the results of a clinical trial for a new allergy medication. The data indicates the percentage of patients in different age groups who reported 'significant symptom relief'.

| Age Group | Placebo Group Relief | Medication Group Relief |
|---|---|---|
| 18-35 | 25% | 60% |
| 36-55 | 30% | 55% |
| 56+ | 28% | 45% |

Which statement is the most accurate interpretation of the data?

Accepted Answer

The medication provided the greatest benefit, compared to the placebo, for the 18-35 age group.

Answer

The medication is ineffective for patients aged 56 and older.

Answer

The placebo effect was strongest in the 18-35 age group.

Answer

The medication is less effective as patients get older.

Question 4

The provided graph shows the population of a certain species of fish in a lake over 10 years, during which a new industrial plant began operations in year 5. The graph shows a steady population from year 1 to 5, followed by a sharp decline from year 6 to 10. Which of the following statements is a valid conclusion based *only* on the data presented?

Accepted Answer

The fish population began to decrease after the industrial plant started operations.

Answer

The industrial plant is solely responsible for the decline in the fish population.

Answer

The lake's ecosystem will not recover from the pollution.

Answer

The fish species will be extinct within another 5 years if the trend continues.

Question 5

A scientist measures the boiling point of pure water at various altitudes. The results are shown in the table below.

| Altitude (meters) | Boiling Point (°C) |
|---|---|
| 0 | 100.0 |
| 1000 | 96.7 |
| 2000 | 93.4 |
| 4000 | 86.8 |

Based on the trend in the data, what is the MOST LIKELY boiling point of water at an altitude of 3,000 meters?

Accepted Answer

90.1°C

Answer

93.5°C

Answer

86.7°C

Answer

91.8°C

Question 6

To investigate the effect of soil pH on tomato plant growth, a student plants five tomato seedlings in identical pots with the same type of soil and gives them the same amount of water and sunlight. The only difference is that the soil for each plant is adjusted to a different pH level (5.0, 5.5, 6.0, 6.5, 7.0). The student measures the final height of each plant after 8 weeks. What is the independent variable in this experiment?

Accepted Answer

The pH level of the soil.

Answer

The final height of the plants.

Answer

The amount of sunlight.

Answer

The type of tomato seedling.