1.2 Prevalence of infidelity

Discussion

Depending on the way infidelity is defined and the sample, research suggests that lifetime prevalence for infidelity is between 15% and 70% (Hertlein et al., 2005) or 1.2% to 85.5% (Luo et al., 2010). A more conservative estimate, based on nationally representative random sample studies suggests a lifetime prevalence for married partners engaging in extradyadic sexual intercourse of up to 25% (Blow and Hartnett, 2005b).

However, reliable estimates of prevalence of a phenomenon rely on having a good definition and there is considerable debate in the literature about how to define infidelity. There is also debate in the counselling room, as not only may partners in a relationship differ in how they define infidelity (Hertlein et al., 2005) but also couple counsellors have different understandings of infidelity (e.g., Bagarozzi, 2008 vs. Whisman and Wagers, 2005).

The apparent confusion around definitions is important theoretically and empirically but it is also important for therapeutic practice with couples in distress (Blow and Hartnett, 2005a), something which is obviously important for this course. For this reason, it makes sense to look further at definitions next.