Testing Theoretical Explanations -------------------------------- Having already tested the primary hypotheses regarding the relationships between concordant solitary pornography use and relationship and sexual satisfaction we are left with a couple of options to examine underlying theoretical mechanisms that may explain these associations. Within this dataset, we have again found clear evidence that solitary pornography use is only negatively related to sexual and relationship satisfaction in couples characterized by high discordance in solitary pornography use. Similar effects have been partially reproduced when analyzing sexual satisfaction and dissatisfaction, but they may be limited to the prediction of sexual satisfaction and dissatisfaction over time using measures of pornography use that were collected at the first of wave of data collection after baseline (T1). Similarity - Dissimilarity -------------------------- One hypothesis is that concordance-discordance effects of solitary pornography use simply reflect what is already known about the role of partner similarity-dissimilarity in sexual attitudes and erotophilia-erotophobia in relationship functioning. Lending weight to this idea, we have found that similarity-dissimilarity in personal attitudes towards own pornography use produce similar patterns of results with respect to sexual satisfaction. To gauge whether or not the effects of concordance-discordance in pornography use are readily explained by more general sexual similarity-dissimilarity, we have also previously tested for concordance-discordance while controlling for similarity-dissimilarity in sexual preferences and erotophilia-erotophobia. The concordance-discordance effect still emerged indicating, at the very least, that it is not entirely redundant with similarity-dissimilarity in these variables. The current dataset provides two further opportunities to examine the similarity-dissimilarity argument. First, attitudes towards a partners' pornography use were measured with a single item during baseline data collection. Second, sex drive was measured with 4 items at baseline data collection. Similarity-dissimilarity in either or both dimensions may explain the concordance-discordance effects, and so we will further further scrutinize significant effects that have emerged while controlling for similarity-dissimilarity in these measures at baseline. Violation of Partner's Expectations of Non-Use ---------------------------------------------- It is also possible that the concordance-discordance effect of solitary pornography use is better represented as the outcome of a partner's violations of sexual expectations within a relationship. Although, pornography use is commonly described as an act of infidelity by sources of popular media (Montgomery-Graham et al., 2015), existent literature suggests that only a minority of people actually feel this way about it (Whitty, 2003). Even if this is not a common perception, violations of an expectation of strict Carteresque (i.e. lust in the heart) monogamy may still be problematic for some couples. To examine this possibility, we will further scrutinize significant concordance-discordance effects by controlling for interactions between one's own solitary pornography use and their partner's attitudes towards pornography, in addition to one's partner's pornography use and one's own attitudes towards pornography.