Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evaluation of adaptive treatment strategies in an observational study
  where time-varying covariates are not monitored systematically   In studies based on electronic health records (EHR), the frequency of
covariate monitoring can vary by covariate type, across patients, and over
time. This can lead to major challenges: first, the difference in monitoring
protocols may invalidate the extrapolation of study results obtained in one
population to the other, and second, monitoring can act as a time-varying
confounder of the causal effect of a time-varying treatment on the outcomes of
interest. This paper demonstrates how to account for non-systematic covariate
monitoring when evaluating dynamic treatment interventions, and how to evaluate
joint dynamic treatment-censoring and static monitoring interventions, in a
real world, EHR-based, comparative effectiveness research (CER) study of
patients with type II diabetes mellitus. First, we show that the effects of
dynamic treatment-censoring regimes can be identified by including indicators
of monitoring events in the adjustment set. Second, we demonstrate the poor
performance of the standard inverse probability weighting (IPW) estimator of
the effects of joint treatment-censoring-monitoring interventions, due to a
large decrease in data support resulting in a large increase in standard errors
and concerns over finite-sample bias from near-violations of the positivity
assumption for the monitoring process. Finally, we detail an alternate IPW
estimator of the effects of these interventions using the No Direct Effect
assumption. We demonstrate that this estimator can result in improved
efficiency but at the cost of increased bias concerns over structural
near-violations of the positivity assumption for the treatment process. To
conclude, this paper develops and illustrates new tools that researchers can
exploit to appropriately account for non-systematic covariate monitoring in
CER, and to ask new causal questions about the joint effects of treatment and
monitoring interventions.

32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph