Continuous Inclusion of Other in the Self (IOS)

FREE for use with an Inquisit Lab or Inquisit Web license.

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Continous Inclusion of Other in Self (Continuous IOS)

A measure of actual and desired relationship closeness developed by Le et al (2007)
Duration: 3 minutes
(Requires Inquisit Lab)
(Run with Inquisit Web)
Last Updated


Google ScholarSearch Google Scholar for peer-reviewed, published research using the Inquisit Continuous Inclusion of Other in the Self (IOS).

Aron, Arthur, Aron, Elaine N, & Smollan, Danny. (1992). Inclusion of Other in the Self Scale and the Structure of Interpersonal Closeness. Journal of Personality and Social Psychology, 63(4), 596-612.

Le, B., Moss, W. B., & Mashek, D. (2007). Assessing Relationship Closeness Online: Moving From an Interval-Scaled to Continuous Measure of Including Others in the Self. Social Science Computer Review, 25(3), 405–409.

Woosnam, Kyle M. (2010). The inclusion of other in the self (ios) scale. Annals of Tourism Research, 37(3), 857-860.

Helgeson, Vicki S, & Van Vleet, Meredith. (2019). Short report: Inclusion of other in the self scale: An adaptation and exploration in a diverse community sample. Journal of Social and Personal Relationships, 36(11-12), 4048-4056.