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Base-rates, cut-points and interaction effects: the problem with dichotomized continuous variables

Published online by Cambridge University Press:  09 July 2009

H. O. F. Veiel
H. O. F. Veiel*
Affiliation:
Central Institute of Mental Health, Mannheim, West Germany
*
1Address for correspondence: Dr H. O. F. Veiel, Central Institute of Mental Health, J–5, D-6800 Mannheim 1, West Germany.
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Synopsis

On the background of the recent discussion about the appropriateness of linear difference and ratio models for testing interaction effects of social support and stress, it is argued that interaction effects are basically unstable when dichotomized continuous variables are analysed. A data set with known interrelationships of the continuous variables ‘stress’, ‘social support’, and ‘depression’ was simulated and analysed in tabular format. It is shown that the choice of cut-points for the independent variables crucially determines the size and presence of interaction effects in ratio analysis models.

Information

Type
Research Article
Information
Psychological Medicine , Volume 18 , Issue 3 , August 1988, pp. 703 - 710
Copyright
Copyright © Cambridge University Press 1988

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References

Alloway, R. & Bebbington, P. (1987). The buffer theory of social support - a review of the literature. Psychological Medicine 17, 91–108.CrossRefGoogle ScholarPubMed
Brown, G. W. (1986). Statistical interaction and the role of social factors in the aetiology of clinical depression. Sociology 20, 601–606.CrossRefGoogle Scholar
Brown, G. W. & Harris, T. (1978). Social origins of depression: a reply. Psychological Medicine 8, 577–588.CrossRefGoogle ScholarPubMed
Cleary, P. D. & Kessler, R. C. (1982). The estimation and interpretation of modifier effects. Journal of Health and Social Behavior 23, 159–169.CrossRefGoogle ScholarPubMed
Cohen, J. (1978). Partialed products are interactions; partialed powers are curve components. Psychological Bulletin 85, 858–866.CrossRefGoogle Scholar
Everitt, B. S. & Smith, A. M. R. (1979). Interactions in contingency tables. a brief discussion of alternative definitions. Psychological Medicine 9, 581–583.CrossRefGoogle ScholarPubMed
Henderson, S., Byrne, D. G. & Duncan-Jones, P. (1981). Neurosis and the Social Environment. Academic Press: London.Google Scholar
McKee, D. & Vilhjalmsson, R. (1986). Life stress, vulnerability and depression: a methodological critique of Brown el al. Sociology 20, 589–599.CrossRefGoogle Scholar
Myers, J. (1979). Fundamentals of Experimental Design (third edn). Allyn & Bacon: Boston.Google Scholar
Parry, G. & Shapiro, D. A. (1986). Social support and life events in working class women. Archives of General Psychiatry 43, 315–323.CrossRefGoogle ScholarPubMed
Reynolds, H. T. (1978). Some comments on the causal analysis of surveys with log-linear models. American Journal of Sociology 83, 127–143.CrossRefGoogle Scholar
Southwood, K. E. (1978). Substantive theory and statistical interaction: five models. American Journal of Sociology 83, 1154–1203.CrossRefGoogle Scholar
Tennant, C. & Bebbington, P. (1978). The social causation of depression: a critique of Brown and his colleagues. Psychological Medicine 8, 565–575.CrossRefGoogle Scholar