Paper: Peasant C, Sullivan TP, Weiss NH, Martinez I, Meyer JP. Beyond the Syndemic: Condom Negotiation and Use among Women Experiencing Partner Violence. AIDS Care. 2017. April. 29(4): 516-523.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5291821/pdf/nihms781142.pdf
Primary discipline of authors: AIDS research, preventive medicine and community research, psychiatry, school of medicine, epidemiology
DAG:
Indirect Effect (a x b) = -6.41*
Syndemic Severity--------> Condom Use
\ c= -1.22 ^
a=-8.33* \ / b=0.77***
\ /
v /
Condom Negotiation
Exposure of Interest: Syndemic Severity of Intimate Partner Violence (scale 0-4) comprised of problematic drug use, hazardous drinking, depression, and posttraumatic stress disorder
Outcome of Interest: Condom Use – percentage of total sexual episodes in which a condom was worn.
Mediator of Interest (how measured): Condom Negotiation was defined as the percentage of instances of sexual intercourse in which the woman asked their partner to wear a condom.
Modeling approach (total, direct and indirect effects): They used PROCESS, ordinary least squares regression and bootstrapping to estimate the direct, indirect effects of the hypothesized associations AFTER they controlled for the covariates and the confounder of fear of condom negotiation. Total effect was -7.63. (SE=2.33, 95% CI: ), Indirect effect was -6.41 (SE = 2.13, 95% CI: -10.71, -2.31) and the Direct effect was -1.22, SE = 2.11, 95% CI: -5.40, 2.99)
Potential for measurement error in mediator: The mediator is being self-reported instances of negotiating condom use, and this is highly susceptible to reporting bias. It is likely socially desirable to report that you attempted to negotiate condom use and to blame the partner for failing to use condoms. Alternatively, women might be hesitant to admit that they asked, but failed to receive consensus on condom use as exemplary of their own lack of agency. It may well be that condom negotiation is under/over reported, but it is not clear in what direction, but it would likely bias the results towards the null as long as they are non-differentially misclassified.
Unmeasured confounders of the mediator-outcome association: They did include fear of condom negotiation, which was my primary thought for confounders of the condom negotiation-condom use association. Other factors might be having the condoms available, so if you know they aren’t available the women probably wouldn’t even ask to begin with.