APA REPORTING GUIDE
How to report a correlation in APA style
An APA-style correlation report names the coefficient (Pearson r, Spearman rₛ, or Kendall τ), gives the degrees of freedom (N − 2) in brackets, the coefficient without a leading zero, the exact p value, and ideally a 95% confidence interval, along with the direction and strength of the relationship.Explore research statistics & data analysis →FORMULA OR CORE IDEA
r(N − 2) = .XX, p = .XXX, 95% CI [.XX, .XX]WORKED EXAMPLE
A Pearson correlation showed a strong positive relationship between weekly study hours and exam score, r(10) = .97, p < .001, 95% CI [.89, .99]. Students who studied more tended to score higher.QUICK REFERENCE
APA correlation templates
Italicise r, p, N, and rₛ in your final document; Greek letters such as τ are not italicised.| Situation | Template | Notes |
|---|---|---|
| Pearson, significant | r(48) = .45, p = .001, 95% CI [.20, .65] | df = N − 2 |
| Pearson, negative | r(48) = −.32, p = .023 | Keep the minus sign |
| Pearson, non-significant | r(48) = .12, p = .406 | Report the exact p |
| Spearman | rₛ(28) = .58, p < .001 | Use for Likert items or skewed data |
| Kendall tau-b | τb = .41, p = .002, N = 30 | Give N instead of df |
| Several correlations | rs ranged from .21 to .64, all ps < .05 | Point to the correlation matrix table |
STEP BY STEP
Name the correlation you used
Pearson's r for two numeric, roughly normal variables with a linear relationship; Spearman's rank-order correlation (rₛ) for ordinal or skewed data; Kendall's tau-b (τb) for small samples or many ties.
Give the degrees of freedom
For Pearson and Spearman, df = N − 2 and goes in brackets: r(48) for 50 participants. Some journals give N instead: r(N = 50). Kendall's tau is usually reported without df.
Write the coefficient without a leading zero
Because a correlation cannot be larger than 1, APA drops the zero: r = .45, not r = 0.45. Keep the minus sign for negative correlations: r = −.32.
Report the exact p value and the confidence interval
Use p = .012 rather than p < .05 (write p < .001 only when it is smaller than .001). Adding the 95% CI shows how precisely r was estimated.
Describe direction and strength in words
Say whether the relationship was positive or negative and weak, moderate, or strong. A common guide: .10 weak, .30 moderate, .50 strong (Cohen, 1988).
Use a correlation matrix for several variables
Put the variables in rows and numbered columns, show r values in the lower triangle, add means and SDs, and mark significance with asterisks explained in a table note.
COMMON QUESTIONS
Frequently asked questions
How do you write a Pearson correlation in APA format?
Write r(df) = .XX, p = .XXX, where df = N − 2. For example: r(28) = .52, p = .003, 95% CI [.20, .74].
How do I report Spearman's correlation in APA?
Use rₛ (r with a subscript s) or ρ: "There was a moderate positive correlation between satisfaction and loyalty, rₛ(58) = .41, p = .001."
Is a correlation of .3 strong?
By Cohen's (1988) benchmarks, .30 is a moderate (medium) correlation. Around .10 is weak (small) and .50 or more is strong (large). In practice, interpret strength relative to similar studies in your field.
Should I report r squared for a correlation?
It is optional but helpful. r² is the proportion of variance the two variables share: r = .50 means r² = .25, or 25% shared variance.
Can I say one variable caused the other?
No. A correlation only shows that two variables are related. Use wording such as "was associated with" or "was related to", not "caused" or "led to".