Table of Contents
When reporting the results of a correlation using Pearson’s r in APA format, report the correlation coefficient (r), the significance level (p), the sample size (n) and the effect size (r2). Include the key results in the text of the paper and provide the full results in the appendix. For example, “The Pearson correlation coefficient, r = .57, was significant, p < .001, n = 123, r2 = .33, indicating that there was a moderate, positive relationship between the two variables.”
A Pearson Correlation Coefficient, often denoted r, measures the linear association between two variables.
It always takes on a value between -1 and 1 where:
- -1 indicates a perfectly negative linear correlation between two variables
- 0 indicates no linear correlation between two variables
- 1 indicates a perfectly positive linear correlation between two variables
We use the following general structure to report a Pearson’s r in APA format:
A Pearson correlation coefficient was computed to assess the linear relationship between [variable 1] and [variable 2].
There was a [negative or positive] correlation between the two variables, r(df) = [r value], p = [p-value].
Keep in mind the following when reporting Pearson’s r in APA format:
- Round the p-value to three decimal places.
- Round the value for r to two decimal places.
- Drop the leading 0 for the p-value and r (e.g. use .77, not 0.77)
- The degrees of freedom (df) is calculated as N – 2.
The following examples show how to report Pearson’s r in APA format in various scenarios.
Example 1: Hours Studied vs. Exam Score Received
A professor collected data for the number of hours studied and the exam score received for 40 students in his class. He found the Pearson correlation coefficient between the two variables to be 0.48 with a corresponding p-value of 0.002.
Here is how to report Pearson’s r in APA format:
A Pearson correlation coefficient was computed to assess the linear relationship between hours studied and exam score.
There was a positive correlation between the two variables, r(38) = .48, p = .002.
Example 2: Time Spent Running vs. Body Fat
A doctor collected data for the number of hours spent running per week and body fat percentage for 35 patients. He found the Pearson correlation coefficient between the two variables to be -0.37 with a corresponding p-value of 0.029.
Here is how to report Pearson’s r in APA format:
A Pearson correlation coefficient was computed to assess the linear relationship between hours spent running and body fat percentage.
There was a negative correlation between the two variables, r(33) = -.37, p = .029.
Example 3: Ad Spend vs. Revenue Generated
Here is how to report Pearson’s r in APA format:
A Pearson correlation coefficient was computed to assess the linear relationship between advertising spend and total revenue.
There was a positive correlation between the two variables, r(13) = .71, p = .003.
The following tutorials explain how to report other statistical tests and procedures in APA format: