Citation
Keil, Alexander P. & Edwards, Jessie K. (2018). A Review of Time Scale Fundamentals in the G-Formula and Insidious Selection Bias. Current Epidemiology Reports, 5(3), 205-213. PMCID: PMC6289285Abstract
PURPOSE OF REVIEW: We review recent examples of data analysis with the g-formula, a powerful tool for analyzing longitudinal data and survival analysis. Specifically, we focus on the common choices of time scale and review inferential issues that may arise.RECENT FINDINGS: Researchers are increasingly engaged with questions that require time scales subject to left-truncation and right-censoring. The assumptions necessary for allowing right-censoring are well defined in the literature, whereas similar assumptions for left-truncation are not well defined. Policy and biologic considerations sometimes dictate that observational data must be analyzed on time scales that are subject to left-truncation, such as age.
SUMMARY: Further consideration of left-truncation is needed, especially when biologic or policy considerations dictate that age is the relevant time scale of interest. Methodologic development is needed to reduce potential for bias when left-truncation may occur.
URL
http://dx.doi.org/10.1007/s40471-018-0153-0Reference Type
Journal ArticleYear Published
2018Journal Title
Current Epidemiology ReportsAuthor(s)
Keil, Alexander P.Edwards, Jessie K.