Juanjuan Fan

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Assessing treatment effects in observational studies is a multifaceted problem that not only involves heterogeneous mechanisms of how the treatment or cause is exposed to subjects, known as propensity , but also differential causal effects across sub-populations. We introduce a concept termed the facilitating score to account for both the confounding and(More)
PURPOSE To test the hypothesis that specific locations and patterns of threshold findings within the visual field have predictive value for progressive glaucomatous optic neuropathy (pGON). METHODS Age-adjusted standard automated perimetry thresholds, along with other clinical variables gathered at the initial examination of 168 individuals with high-risk(More)
This paper is concerned with developing rules for assignment of tooth prognosis based on actual tooth loss in the VA Dental Longitudinal Study. It is also of interest to rank the relative importance of various clinical factors for tooth loss. A multivariate survival tree procedure is proposed. The procedure is built on a parametric exponential frailty(More)
PURPOSE To evaluate whether baseline visual field data and asymmetries between eyes predict the onset of primary open-angle glaucoma (POAG) in Ocular Hypertension Treatment Study (OHTS) participants. METHODS A new index, mean prognosis (MP), was designed for optimal combination of visual field thresholds, to discriminate between eyes that developed POAG(More)
Greedy search or exhaustive search plays a critical role in recursive partitioning and their extensions. We examine an alternative method by replacing the indicator threshold function involved in recursive partitioning with a smooth sigmoid surrogate (SSS) function. In many scenarios, it is important to formulate the problem appropriately, which can change(More)
Despite modern combination antiretroviral therapy, distal neuropathic pain (DNP) continues to affect many individuals with HIV infection. We evaluated risk factors for new-onset DNP in the CNS Antiretroviral Therapy Effects Research (CHARTER) study, an observational cohort. Standardized, semiannual clinical evaluations were administered at 6 US sites.(More)
Studies of ocular disease and analyses of time to disease onset are complicated by the correlation expected between the two eyes from a single patient. We overcome these statistical modeling challenges through a nonparametric Bayesian frailty model. While this model suggests itself as a natural one for such complex data structures, model fitting routines(More)