CSCS Data Analysis & Reporting 2 — Questions and Answers
Question 1: A strength coach calculates a Pearson correlation of r = 0.82 between vertical jump height and 40-yard dash time in athletes. How should this be interpreted?
- Strong positive relationship — faster athletes also jump higher
- Strong negative relationship — faster athletes tend to jump higher (Correct answer)
- Weak relationship indicating no practical significance
- Moderate positive relationship requiring further investigation
Correct answer: Strong negative relationship — faster athletes tend to jump higher
r = 0.82 is a strong negative relationship (if expressed as negative), but since sprint time is inverse to speed, faster 40-yard times (lower numbers) correlate strongly with greater jump height.
Question 2: When reporting athlete performance data, the coefficient of variation (CV) is best used to:
- Determine the statistical significance of group differences
- Assess relative variability between measurements with different units (Correct answer)
- Calculate the minimum detectable change in performance
- Establish normative percentile rankings for a population
Correct answer: Assess relative variability between measurements with different units
CV expresses standard deviation as a percentage of the mean, allowing relative variability comparison across measures with different scales or units.
Question 3: A coach uses a repeated-sprint protocol and finds the intraclass correlation coefficient (ICC) = 0.95. What does this indicate?
- The test has poor test-retest reliability
- The test shows excellent reliability between repeated measurements (Correct answer)
- The measurements are not valid for assessing power
- There is significant systematic bias between test sessions
Correct answer: The test shows excellent reliability between repeated measurements
An ICC ≥ 0.90 is generally considered excellent reliability, indicating highly consistent results across repeated administrations.
Question 4: Which statistical measure represents the smallest change in a performance variable that exceeds measurement error and can be attributed to a true change?
- Standard error of the mean (SEM)
- Minimal detectable change (MDC) (Correct answer)
- Cohen's d effect size
- 95% confidence interval width
Correct answer: Minimal detectable change (MDC)
The minimal detectable change (MDC) is derived from measurement error and defines the threshold above which a change is considered real rather than noise.
Question 5: An athlete's 1RM squat improves from 200 lb to 215 lb. What type of data representation best communicates this change to a non-technical audience?
- A scatter plot with regression line
- A percentage change calculation (7.5% increase) (Correct answer)
- A z-score relative to population norms
- An ANOVA table with F-statistic
Correct answer: A percentage change calculation (7.5% increase)
Percentage change is intuitive for non-technical audiences and clearly conveys magnitude of improvement in practical terms.
Question 6: When comparing strength gains between a trained group and a control group, which statistical test is most appropriate if both groups show normally distributed data?
- Pearson correlation coefficient
- Chi-square test of independence
- Independent samples t-test (Correct answer)
- Spearman rank-order correlation
Correct answer: Independent samples t-test
An independent samples t-test compares means between two unrelated groups when data are normally distributed and measured on a continuous scale.
Question 7: A CSCS practitioner reports Cohen's d = 1.2 for a training intervention. According to conventional benchmarks, how should this effect size be classified?
- Small effect
- Medium effect
- Large effect (Correct answer)
- Trivial effect
Correct answer: Large effect
Cohen's d ≥ 0.8 is classified as a large effect size, with d = 1.2 indicating a very large practical difference between conditions.
CSCS Data Analysis & Reporting 2
A strength coach calculates a Pearson correlation of r = 0.82 between vertical jump height and 40-yard dash time in athletes.
How should this be interpreted?