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Event Probabilities Risks and Regression Methods
The occurrence of an event over time is often summarized by the incidence rate, defined as the average number of events per person-time. This type of rate applies to events that may occur repeatedly over time, such as headaches and infections. We developed nonparametric methods for obtaining incidence risks and regression methods for modeling the probability of events that can occur only once, such as death or first onset of a disease.
Papers
Bottai M. A regression method for modelling geometric rates. Stat Methods Med Res. 2017, 26(6): 2700-2707 (first published 2015).

Discacciati A, Bottai M. Instantaneous geometric rates via generalized linear models. Stata J. 2017, 17(2): 358-371.

Bottai M, Discacciati A, Santoni G. Defining and modeling the probability of occurrence of events. Working Paper 2020.

Bottai M, Discacciati A, Santoni G. Modeling the probability of occurrence of events. Stat Methods Med Res. 2021 Aug;30(8):1976-1987.

Bottai M. Estimating the risk of events with stprisk. Stata Journal, 22(4): 969-974, 2022


Software
Download the stprisk command in Stata:

net install stprisk, from(http://www.imm.ki.se/biostatistics/stata) replace

Download the stpreg command in Stata:

net install stpreg, from(http://www.imm.ki.se/biostatistics/stata) replace

Download the GLM links in Stata:

net install st0478.pkg, from(http://www.stata-journal.com/software/sj17-2/)

Worked-out example in Stata: Survival in metastatic renal carcinoma

Download the GLM links for R

Worked-out example in R: Survival in metastatic renal carcinoma 		Applications
Santoni G, Lagergren J, Bottai M. ASO Authors Reflections: Patient Age and Survival After Surgery for Esophageal Cancer. Ann Surg Oncol. 2020 May 29. doi: 10.1245/s10434-020-08661-w.

Lagergren J, Bottai M, Santoni G. Patient Age and Survival After Surgery for Esophageal Cancer. Ann Surg Oncol. 2020 May 28. doi: 10.1245/s10434-020-08653-w.


Presentations
August 30, 2019
Instantaneous geometric rates via generalized linear models
2017 Nordic and Baltic Stata Users Group Meeting, Stockholm, Sweden

September 1, 2017
Modeling the probability of occurrence of events with the new stpreg command
2019 Nordic and Baltic Stata Users Group Meeting, Stockholm, Sweden

July 15, 2016
Regression modeling of geometric rates
Workshop on Recent Advances in Quantile and M-quantile Regression, Pisa, Italy

September 4, 2015
The grreg command for estimating geometric rate regression
2015 Nordic and Baltic Stata Users Group Meeting, Stockholm, Sweden

March 16, 2015
Modeling geometric rates with quantile regression
Swedish Statistical Society Annual Meeting, Stockholm, Sweden

January 15, 2015
Modeling geometric rates with quantile regression
Dep. Mathematics, University of Cagliari, Italy

Unit of Biostatistics, Nobels väg 13, Karolinska Institutet, 17177 Stockholm, Sweden