Spearman Rank Coefficient (\(\rho\))

Authors

Affiliations

Nate Yomogida, PT, DPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, PT, DPT

Doctor of Physical Therapy

B.A. in Neuroscience

Abbreviations & other names:

• \(\rho\)
• r_s

Comparison to other tests

See Spearman Rank coefficient (\(\rho\)) vs pearson product-moment correlation (r) vs linear regression

Purpose

• Similar to Pearson Correlation Coefficient¹
• Ordinal data¹
• Not restricted to Continuous variables¹
• Ranking converts nonlinear data into a linear relationship¹

Measure: Strength of relationship between the ranks of the values of 2 variables¹

Range

-1 to +1¹

Interpretation

Observed correlation does NOT assume causation only Association¹

References

1.

Schober P, Boer C, Schwarte LA. Correlation Coefficients: Appropriate Use and Interpretation. Anesthesia and Analgesia. 2018;126(5):1763-1768. doi:10.1213/ANE.0000000000002864