Coital Agreement Definition
Our study confirms that coincident dilution is a phenomenon that should be taken into account in simulation studies on the effects of partnership savings on the spread of the HIV epidemic. However, we also note that (a) further empirical studies are needed to establish their relationship with partnership economics (our results have not always been conclusive) and (b) do not directly translate our results into the assumptions underlying the Sawers et al. simulations . First, we model coital frequency as dichotomous sex outcomes in the (last) month in primary and secondary partnerships, while cotal dilution occurs only in Sawers et al.  simulations as a reduction in the monthly rate of HIV transmission in secondary partnerships. Second, and more importantly, Sawers et al. impose a strong number of partnerships within the simulated population, as it allows for a direct comparison of partnership economy and serial monogamy scenarios (in this sense, they follow the example of Morris and Kretzschmar) [7, 16]. The addition of coincided dilution to these models therefore implies that the total number of co-eds coincidents decreases as the frequency of partnership parity increases (with the expected mitigating effects on epidemiology). In our study, we find some evidence of a reduction in cotal frequency when one of the partners in the index relationship has simultaneous partners, but we cannot make assertions about the population of the number of coitals.
The latter will depend in large part on the link between parallelism and the level of the partnership population, and it is quite possible that the assumption of a fixed number of partnerships to simulate scenarios with or without parallelism is as unrealistic as the assumption of a fixed number of coitals per partnership9. The questions unfolded in the following way. Respondents were first asked, “Did you have sex during this relationship, you and [the partner]?” If so, interviewees were asked: “During the first month, you had sex, how many times did you have sex and [partner]? Has the frequency changed during the relationship? When?“ Interviewers were ordered to repeat this investigation during the last month of the relationship. The response categories for the monthly coitale frequency measurement were 0 times, 1-4 times, 5-14 times and 15 or more times. To ensure comparability with the NSF dataset, we reduced this categorical report on cotal frequency in a dichotomy variable with a value of 0 if the respondent does not report sex per month, and 1 if the respondent reports that he had sex during the month. In a series of advanced analyses (see Tables 3, 9)9), we model the coital frequency (1-4 times vs. 5 or more times) among those who report sex per month. We use two analytical strategies to address misinformation about sexual partnerships and the number of sexual acts. First, we use the network nature of LNS data to link partners to assess the reliability of their cotal frequency reports. Appropriate couple relationships are a necessary but insufficient condition for accurate reports on coitusal frequency within a relationship .
Second, using the longitudinal nature of ULYKP relational data, we use the solid effects estimate to control non-observable characteristics within individuals and relationships that may influence bias in coverage.