02371nas a2200229   4500000000100000008004100001260001200042653001400054100001600068700001500084700001300099700001400112700001600126700001300142700001600155245014300171856009900314300001300413490000700426520169400433022001402127       2021                            d  c01/202110aAdherence1 aHardwick RJ1 aTruscott J1 aOswald W1 aWerkman M1 aHalliday KE1 aPullan R1 aAnderson RM00aIndividual adherence to mass drug administration in neglected tropical disease control: A probability model conditional on past behaviour.  uhttps://journals.plos.org/plosntds/article/file?id=10.1371/journal.pntd.0009112&type=printable  ae00091120 v153 a<p>We present a general framework which describes the systematic (binary) scenario of individuals either taking treatment or not for any reason, over the course of mass drug administration (MDA)-which we refer to as 'adherence' and 'non-adherence'. The probability models developed can be informed by observed adherence behaviour as well as employed to explore how different patterns influence the impact of MDA programmes, by the use of mathematical models of transmission and control. We demonstrate the interpretative value of the developed probability model employing a dataset collected in the TUMIKIA project, a randomised trial of deworming strategies to control soil-transmitted helminths (STH) by MDA conducted in coastal Kenya. We stratify our analysis by age and sex, although the framework which we introduce here may be readily adapted to accommodate other stratifications. Our findings include the detection of specific patterns of non-adherence in all age groups to varying extents. This is particularly apparent in men of ages 30+. We then demonstrate the use of the probability model in stochastic individual-based simulations by running two example forecasts for the elimination of STH transmission employing MDA within the TUMIKIA trial setting with different adherence patterns. This suggested a substantial reduction in the probability of elimination (between 23-43%) when comparing observed adherence patterns with an assumption of independence, with important implications for programmes. The results here demonstrate the considerable impact and utility of considering non-adherence on the success of MDA programmes to control neglected tropical diseases (NTDs).</p>  a1935-2735