A factor analysis of the Klein sexual orientation Grid in two disparate samples

Many researchers interested in sexual orientation can be separated into two camps: The “lumpers,” who try to reduce sexual classifications to as small a number of categories as possible, and the “splitters,” who try to show differences among groups and individuals that make classification schemes increasingly difficult and/or intricate. We report factor analyses of the Klein Grid (a questionnaire with 21 sexual orientation items) to see how many factors emerge in two samples of strikingly different origins. In both samples, the first factor to emerge loaded substantially on all of the Klein Grid's 21 items. This factor accounted for a majority of the variance. In both samples, a second, correlated factor emerged which indexed a separation between most of the items and those having to do with social and/or emotional preferences. In both samples, a third correlated factor also emerged, but this factor differed between the two populations: one refined the social/emotional distinction and the other distinguished ideal behavior from past and current behavior. We conclude on the basis of our analysis that both the lumpers and the splitters are correct.

Authors and Affiliations

1. HIV Neurobehavioral Research Center, University of California, San Diego, 2760 Fifth Avenue #200, 92103, San Diego, California, USA

   James D. Weinrich Ph.D., Igor Grant M.D., Denise L. Jacobson M.P.H., S. Renée Robinson R.N., M.A., M.F.C.C. & J. Allen McCutchan M.D.

2. Department of Psychiatry, Hillside Hospital—Research, Long Island Jewish Medical Center, P.O. Box 38, 11004, Glen Oaks, NY, USA

   Peter J. Snyder Ph.D.

3. Department of Psychiatry, Boston University School of Medicine, 85 E. Newton Street M-905, 02118, Boston, Massachusetts, USA

   Richard C. Pillard M.D.

Supported by NIMH grants IP50 MH 45294 and R01 MH 43298.

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