In some quantitative studies the terms quot;external validityquot; and quot;generalizabilityquot; are portrayed as synonymous.

In some quantitative studies the terms "external validity" and "generalizability" are portrayed as synonymous. In contrast, Reichardt (2011) makes the claim that external validity and generalizability should be considered distinct concepts. What is external validity? What are the merits of distinguishing between external validity and generalizability of quantitative results?

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