DOI: 10.5061/dryad.2ngf1vhjn
title: Predicting the impact of patient and private provider behaviour on diagnostic delay for pulmonary tuberculosis patients in India: A simulation modelling approach

description: Background TB incidence in India continues to be high due, in large part,
 to long delays experienced by patients before successful diagnosis and
 treatment initiation, especially in the private sector. This diagnostic
 delay is driven by patients’ inclination to switch between different type
 of providers and providers’ inclination to delay ordering of accurate
 diagnostic tests relevant to TB. Our objective is to quantify the impact
 of changes in these behavioural characteristics of providers and patients
 on diagnostic delay experienced by pulmonary TB patients. Methods/Findings
 We develop a discrete event simulation model of patients’ diagnostic
 pathways that captures key behavioural characteristics of providers (time
 to order a test) and patients (time to switch to another provider). We
 use Expectation-Maximization algorithm to estimate the
 parameters underlying these behavioural characteristics with quantitative
 data encoded from detailed interviews of 76 and 64 pulmonary TB patients
 in two Indian cities of Mumbai and Patna, respectively, which were
 conducted in 2014. We employ the estimated model to simulate different
 counterfactual scenarios of diagnostic pathways under altered behavioural
 characteristics of providers and patients to predict their potential
 impact on the diagnostic delay. Private healthcare providers including
 chemists are the first point of contact for majority of TB patients in
 Mumbai (70%) and Patna (94%). In Mumbai, 44.6% TB patients first approach
 less-than-fully qualified providers (LTFQs), who take 29 days on average
 for diagnosis. Consequently, about 60.7% of the patients switch to other
 providers without a diagnosis. Immediate testing for tuberculosis by LTFQs
 at the first visit (at the current level of diagnostic accuracy) could
 reduce the average diagnostic delay by 17 days (47.3% reduction). In
 Patna, 61% TB patients first approach fully qualified providers (FQs), who
 take 10 days on average for diagnosis. Similarly, immediate testing by FQs
 at the first visit (at the current level of diagnostic accuracy) could
 reduce the average diagnostic delay by 12 days (52.3% reduction).
 Improving diagnostic accuracy of providers, per se, without reducing the
 time to testing, is not predicted to lead to any reductions in diagnostic
 delay. Our study was limited because of its restricted geographic scope,
 small sample size, and possible recall bias, which are typically
 associated with study of patient pathways using patient interviews.
 Conclusions Encouraging private providers to order definitive TB
 diagnostic tests earlier during patient consultation may have greater
 impact on reducing diagnostic delay in these urban Indian settings. These
 results should be combined with disease transmission models to predict the
 impact of changes in provider behaviour on TB incidence.
description: Dataset was collected by conducting detailed patient interviews
 about the pathways followed by the patients until they received the
 correct tuberculosis diagnosis followed by quantitative codificaiton
 of their responses. The data collection was done in two cities - Mumbai
 and Patna. This particular dataset refers only to Patna. The data from
 Mumbai can be found at https://datadryad.org/stash/dataset/doi:10.5061/dryad.bt36t.
description: Each row in the the dataset corresponds to one patient and the
 columns correspond to the demographic details of the patients, followed by
 initial healthcare seeking behavior and finally, details of their each
 stage of consultation with a different provider. More details are
 available in the accompnied attachment "Pathways
 Data_Read_Me.txt".