INFIDELITY IN COMMITTED RELATIONSHIPS I: A METHODOLOGICAL REVIEW

Journal of Marital and Family Therapy, Apr 2005 by Blow, Adrian J, Hartnett, Kelley

The Retrospective, Cross-Sectional Nature of Infidelity Studies

Two major weaknesses of infidelity research are that studies are mostly cross-sectional, and the data are gathered retrospectively (i.e., after the fact of the infidelity). This is a very important consideration, given that many of the studies attempt to ascertain what predicts infidelities after they have already occurred. Atkins et al. (2001) report that the retrospective dilemma "makes it impossible to know about the temporal order of our predictors" (p. 747).

As such, infidelity research becomes a chicken-or-the-egg paradox: Does marital dissatisfaction predict infidelity, or does infidelity predict marital dissatisfaction? The retrospective analysis of a relationship after a significant relational injury quite likely leads to inaccurate reports of these important variables. For example, in cross-sectional studies that measure relationship satisfaction (e.g., Atkins et al., 2001), the variable of relationship satisfaction is measured after the infidelity, making it impossible to control for the effects of the infidelity on the relationship satisfaction. This speaks to the limitations of cross-sectional studies in this kind of research, as well as to the clear need for longitudinal studies on relationships and the role of infidelity in these relationships. Beach et al. (1985) suggest that:

Longitudinal work examining the impact of extramarital sexual activity on marital relationships in the general community [as opposed to clinical populations] is called for to begin the task of better understanding the impact of extramarital sexual activity and the factors differentiating persons seeking therapy from those not seeking therapy. (p. 107)

Longitudinal studies would also help to capture important differences between individuals who have the same vulnerabilities concerning infidelity. For example, if two individuals have the same opportunity to engage in infidelity, why does one succumb and the other resist? The research does not answer this question, and it is difficult to answer given the current limitations in research designs.

Amato and Rogers (1997) offer an example of a longitudinal study that captures the nature of infidelity, yet still has some weaknesses. The authors define infidelity in terms of a sexual relationship with someone else, and they ask questions of only one of the partners in the relationship. This study highlights the difficulty of collecting accurate data even in longitudinal studies. For longitudinal studies to be more accurate, on-going data need to be collected that specifically address all aspects of infidelity (e.g., emotional, sexual, and the like) and from both partners in the relationship. It would be highly useful if data were collected on individuals and relationships in the midst of infidelity. Admittedly, such studies are complex, sensitive, labor intensive, and expensive to carry out.

The Lack of Random Sampling in Many Studies

Some studies analyzed data from large, national samples (Amato & Rogers, 1997; Atkins et al., 2001; Laumann et al., 1994). In large part, these studies were designed to gather general data on relationships, not necessarily to focus directly on the subject of infidelity. As you may notice (Appendix), most studies that gathered data specifically about infidelity used nonrandom samples, and several studies based their findings on clinical samples (e.g., Beach et al., 1985; Schneider, Corley, & Irons, 1998).