In studies of medical treatments, individuals often experience post-treatment events that predict their future outcomes. In this work, we study how to use initial observations of a recurrent event - a type of post-treatment event - to offer updated treatme ...
Point identification of causal effects requires strong assumptions that are unreasonable in many practical settings. However, bounds on these effects can often be derived under plausible assumptions. Even when these bounds are wide or cover null effects, t ...
Birth rates in Canada and the United States declined sharply in March 2020 and deviated from historical trends. This decline was absent in similarly developed European countries. We argue that the selective decline was driven by incoming individuals, who w ...
Avoiding harm is an uncontroversial aim of personalized medicine and other epidemiologic initiatives. However, the precise mathematical translation of "harm"is disputable. Here, we use a formal causal language to study common, but distinct, definitions of ...
Young age is associated with increased risk of recurrence in hormone receptor (HR)–positive early-stage breast cancer (eBC). Lack of adherence to endocrine therapy (ET) is a potential reason for the lower survival proportions observed in younger patients, ...
Pathogens usually exist in heterogeneous variants, like subtypes and strains. Quantifying treatment effects on the different variants is important for guiding prevention policies and vaccine development. Here, we ground analyses of variant-specific effects ...
Risk ratios are one of the most commonly used effect measures in epidemiology. Yet their properties and transportability across different populations remain debated. In this article, we show that the causal risk ratio is stable to selection based on immune ...
Hazard ratios are routinely reported as effect measures in clinical trials and observational studies. However, many methodological works have raised concerns about the interpretation of hazard ratios as causal effects. These concerns are often related to t ...
We recently questioned the utility of testing for proportional hazards in survival analysis. Here, we expand on why the proportional hazards assumption is both implausible and unnecessary in most medical studies, particularly in randomized trials. We concl ...
Comparing different medications is complicated when adherence to these medications differs. We can overcome the adherence issue by assessing effectiveness under sustained use, as in usual causal "per-protocol" estimands. However, when sustained use is chal ...
In our original article, we examine twin definitions of "harm" in personalized medicine: a first based on predictions of individuals' unmeasurable response types (counterfactual harm), and a second based solely on the observations of experiments (intervent ...
In survival studies, all participants are rarely followed until they die. Methods for lifetime analysis are designed to handle such incompletely observed lifetimes. We call these lifetimes censored. The standard method for lifetime analysis assumes that th ...
The interpretation of vaccine efficacy estimands is subtle, even in randomized trials designed to quantify the immunologic effects of vaccination. In this article, we introduce terminology to distinguish between different vaccine efficacy estimands and cla ...
Cardiovascular (CV) risk factors for rheumatoid arthritis (RA) are conventionally classified as 'traditional' and 'novel'. We argue that this classification is obsolete and potentially counterproductive. Further, we discuss problems with the common practic ...
We consider optimal regimes for algorithm-assisted human decision-making. Such regimes are decision functions of measured pre-treatment variables and, by leveraging natural treatment values, enjoy a superoptimality property whereby they are guaranteed to o ...
Sometimes treatment effects are absent in a subgroup of the population. For example, penicillin has no effect on severe symptoms in individuals infected by resistant Staphylococcus aureus, and codeine has no effect on pain in individuals with certain polym ...
Knowing whether vaccine protection wanes over time is important for health policy and drug development. However, quantifying waning effects is difficult. A simple contrast of vaccine efficacy at two different times compares different populations of individ ...
Many research questions concern treatment effects on outcomes that can recur several times in the same individual. For example, medical researchers are interested in treatment effects on hospitalizations in heart failure patients and sports injuries in ath ...
