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The reliability of a two-item scale: Pearson, Cronbach, or Spearman-Brown?

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International Journal of Public Health

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The authors are grateful to William Revelle and an anonymous reviewer for helpful comments on a previous version of this manuscript and suggestions for improvements.

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Correspondence to Rob Eisinga.

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Eisinga, R., Grotenhuis, M.t. & Pelzer, B. The reliability of a two-item scale: Pearson, Cronbach, or Spearman-Brown?. Int J Public Health 58, 637–642 (2013).

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