Estimands, estimators and estimates

23 August 2021 - The primary goal of most randomised clinical trials is to draw conclusions about the effect of a ...

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Immortal time bias in observational studies

16 February 2021 - Observational studies are commonly used to evaluate the association between a risk factor or “exposure” and the ...

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Even before year end, 2020's new drug approvals match FDA's 2019 stats

7 December 2020 - The US FDA has kept its new drug approvals for 2020 on track to match or ...

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Worst-rank score methods—a non-parametric approach to informatively missing data

28 September 2020 - A previous JAMA Guide to Statistics and Methods article briefly reviewed non-parametric statistics.  ...

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Estimating risk ratios and risk differences: alternatives to odds ratios

15 September 2020 - The goal of many medical research studies is to estimate the direction and magnitude of the effect ...

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Regression discontinuity design

2 July 2020 - The method is used to study the outcomes related to an abrupt change when it is not ...

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Why test for proportional hazards?

13 March 2020 - The Cox proportional hazards model, introduced in 1972, has become the default approach for survival analysis in ...

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Using instrumental variables to address bias from unobserved confounders

2 May 2019 - Randomised clinical trials are considered the most reliable source of evidence for the effects of medical interventions, ...

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The importance of predefined rules and pre-specified statistical analyses: do not abandon significance

4 April 2019 - For decades, statisticians and clinicians have debated the meaning of statistical and clinical significance.  ...

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The stepped wedge cluster randomised trial: what it is and when it should be used

1 April 2019 - The basic premise of a stepped wedge cluster randomised trial is that all clusters start in the ...

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Marginal effects—quantifying the effect of changes in risk factors in logistic regression models

8 March 2019 - Marginal effects can be used to express how the predicted probability of a binary outcome changes ...

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Number needed to treat: conveying the likelihood of a therapeutic effect

7 February 2019 - Effectively communicating clinical trial results to patients and clinicians is a requirement for appropriate application in ...

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Using the E value to assess the potential effect of unmeasured confounding in observational studies

24 January 2019 - Randomised trials serve as the standard for comparative studies of treatment effects.  ...

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Random-effects meta-analysis: summarising evidence with caveats

22 January 2019 - Questions involving medical therapies are often studied more than once. For example, numerous clinical trials have been ...

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Challenges of non-intention-to-treat analyses

15 January 2019 - Over the past 5 decades, the randomised clinical trial has become the gold standard for evaluation ...

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