Improving social harm indices with a modulated Hawkes process

Communities are affected adversely by a range of social harm events, such as crime, traffic crashes, medical emergencies, and drug use. The police, fire, health and social service departments are tasked with mitigating such social harm through various types of interventions. While various different social harm indices have been proposed for allocating resources to spatially fixed hotspots, the risk of social harm events is dynamic, and new algorithms and software systems that are capable of quickly identifying risks and triggering appropriate public safety responses are needed. We propose a novel modulated Hawkes process for this purpose that offers flexible approaches to both (i) the incorporation of spatial covariates and leading indicators for variance reduction in the case of rarer event categories, and (ii) the capture of dynamic hotspot formation through self-excitation. We present an efficient l1-penalized EM algorithm for estimating the model that performs feature selection for the spatial covariates of each incident type simultaneously. We provide simulation results using data from the Indianapolis Metropolitan Police Department in order to illustrate the advantages of the modulated Hawkes process model of social harm over various recently introduced social harm indices and property crime Hawkes processes.     

A cost-effectiveness analysis of denosumab for the prevention of skeletal-related events in patients with multiple myeloma in the United States of America

Objective: A large, pivotal, phase 3 trial in patients with newly diagnosed multiple myeloma (MM) demonstrated that denosumab, compared with zoledronic acid, was non-inferior for the prevention of skeletal-related events (SREs), extended the observed median progression-free survival (PFS) by 10.7 months, and showed significantly less renal toxicity. The cost-effectiveness of denosumab vs zoledronic acid in MM in the US was assessed from societal and payer perspectives.

Methods: The XGEVA Global Economic Model was developed by integrating data from the phase 3 trial comparing the efficacy of denosumab with zoledronic acid for the prevention of SREs in MM. SRE rates were adjusted to reflect the real-world incidence. The model included utility decrements for SREs, administration, serious adverse events (SAEs), and disease progression. Drug, administration, SRE management, SAEs, and anti-MM treatment costs were based on data from published studies. For the societal perspective, the model additionally included SRE-related direct non-medical costs and indirect costs. The net monetary benefit (NMB) was calculated using a willingness-to-pay threshold of US$150,000. One-way deterministic and probabilistic sensitivity analyses were conducted.

Results: From a societal perspective, compared with zoledronic acid, the use of denosumab resulted in an incremental cost of US$26,329 and an incremental quality-adjusted life-year (QALY) of 0.2439, translating into a cost per QALY gained of US$107,939 and a NMB of US$10,259 in favor of denosumab. Results were sensitive to SRE rates and PFS parameters.

Limitations: Costs were estimated from multiple sources, which varied by tumor type, patient population, country, and other parameters. PFS and overall survival were extrapolated beyond the follow-up of the primary analysis using fitted parametric curves.

Conclusion: Denosumab’s efficacy in delaying or preventing SREs, potential to improve PFS, and lack of renal toxicity make it a cost-effective option for the prevention of SREs in MM compared with zoledronic acid.