Quantitative Issues in Cancer Research Working Seminar

Jonathan Luu
Doctoral Student, Department of Biostatistics, Harvard University

“Analyzing Clustered Semi-Continuous Data Subject to Mortality”

ABSTRACT: In the nursing home setting, costs and healthcare utilization are two common outcomes of interest. However, cost data typically follows a semi-continuous distribution, with a large concentration of zero values and a right skewed distribution of positive values. First, I will discuss the logistic-lognormal two-part model commonly used to analyze this data. Furthermore, I will talk about the Bayesian semiparametric framework for the random effects we are proposing to extend this model’s flexibility. Second, metrics often used to compare semi-continuous data do not consider the that the data arise from two distinct stochastic processes: one that governs the occurrence of zeros and the other determining the observed value conditional on it being a non-zero response. I will discuss two-dimensional metrics we are developing that jointly look at performance in terms of whether more than expected people are accruing non-zero costs and whether those folks who do accrue non-zero costs are accruing more than expected such costs.