Tim T Morris

TL;DR: The challenge of interpreting observational evidence from non-representative samples used to identify risk factors for infection with SARS-CoV-2 and COVID-19 disease outcomes is highlighted.

TL;DR: The challenge of interpreting observational evidence from samples of the population, which may be affected by collider bias, is highlighted using data from the UK Biobank in which individuals tested for COVID-19 are highly selected for a wide range of genetic, behavioural, cardiovascular, demographic, and anthropometric traits.

TL;DR: Methods for within-family Mendelian randomization analyses are described and simulation studies are used to show that family-based analyses can reduce such biases in Mendelians randomization through within- family studies.

TL;DR: It is demonstrated that both heritability and genetic correlation may be biased estimates of the causal contribution of genotype, and use of these methods in combination with family-based designs may offer researchers greater opportunities to explore the mechanisms driving genotype-phenotype associations.

TL;DR: In this paper , the authors combined data from 178,086 siblings from 19 cohorts to generate population (between-family) and within-sibship (within family) estimates for 25 phenotypes.