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David H. Solomon, MD
Torrance, Calif

JAMA. 1970;212(10):1706.

	Since this article does not have an abstract, we have provided the first 150 words of the full text PDF and any section headings.

To the Editor.—

The paper by Drs. Geller et al (210:1421-1427, 1969), contains a rather gross statistical error, affecting the interpretation of the entire study. On page 1424, the authors state that chi-square test was highly significant (P< 0.005) based on six of ten good results in the treated group vs two of ten good results in the controls. The calculation must have gone awry, since chi-square for these data is 3.33 without correction and even lower, 1.875, employing Yates correction for continuity, which should be employed for small samples like those in this study. Neither of these chi-squares, with one degree of freedom, allows a conclusion of a significant result. In fact, P for chi-square of 3.33 is >0.05 and for 1.875 is >0.10.

The reason I checked the chisquare calculation was that instinct tells one that ten cases in each group is simply not enough to . . . [Full Text PDF of this Article]

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