Uncertainty analyses with the mixing parameter and different distributions of the testing uptakes in the SB–RP groups (SB–RP model). Uncertainty analyses with the mixing parameter and different distributions of the testing uptakes in the SB–RP groups (SB–RP model). (a,b) The estimated chlamydia prevalence in each group for five consecutive years after the introduction of the baseline testing scenario (solid lines) and the testing scenario with differential uptake in SB–RP groups (dashed lines) for a value of the mixing parameter of zero (fully assortative mixing, a) or one (fully proportionate mixing, b). Note that the prevalence in the pessimists and low-risk realists is zero when the value of the mixing parameter is set to zero. (c) The relative difference in chlamydia prevalence between the baseline testing scenario and the testing scenario with differential uptake in SB–RP groups after 5 years is shown for different distributions of the testing uptake in the SB–RP groups, keeping an overall testing uptake of 10%. The testing uptake distribution over the SB–RP groups was explored continuously by steps of 1%, starting at uptake in low risk perception groups = 0 (0% uptake in the low-risk realists and optimists, and 100% uptake in the pessimists and high-risk realists) to uptake in low risk perception groups = 100 (100% uptake in the low-risk realists and optimists, and 0% uptake in the pessimists and high-risk realists). (d) The prevalence of chlamydia in each group and the total population, for these different distributions of testing uptake in SB–RP groups. Daphne A. van Wees et al. J. R. Soc. Interface 2018;15:20170847 © 2018 The Author(s)‏