
ABSTRACTThe results of randomized clinical trials (RCTs) are frequently assessed with the fragility index (FI). Although the information provided by FI may supplement the p value, this indicator presents intrinsic weaknesses and shortcomings. In this article, we establish an analysis of fragility within a broader framework so that it can reliably complement the information provided by the p value. This perspective is named the analysis of strength. We first propose a new strength index (SI), which can be adopted in normal distribution settings. This measure can be obtained for both significance and nonsignificance and is straightforward to calculate, thus presenting compelling advantages over FI, starting from the presence of a threshold. The case of time‐to‐event outcomes is also addressed. Then, beyond the p value, we develop the analysis of strength using likelihood ratios from Royall's statistical evidence viewpoint. A new R package is provided for performing strength calculations, and a simulation study is conducted to explore the behavior of SI and the likelihood‐based indicator empirically across different settings. The newly proposed analysis of strength is applied in the assessment of the results of three recent trials involving the treatment of COVID‐19.
Likelihood Functions, Models, Statistical, SARS-CoV-2, COVID-19, COVID-19 Drug Treatment, Research Design, Data Interpretation, Statistical, fragility index; likelihood ratio; randomized clinical trial; strength index, Main Paper, Humans, Computer Simulation, fragility index; likelihood ratio; randomized clinical trial; strength index;, Randomized Controlled Trials as Topic
Likelihood Functions, Models, Statistical, SARS-CoV-2, COVID-19, COVID-19 Drug Treatment, Research Design, Data Interpretation, Statistical, fragility index; likelihood ratio; randomized clinical trial; strength index, Main Paper, Humans, Computer Simulation, fragility index; likelihood ratio; randomized clinical trial; strength index;, Randomized Controlled Trials as Topic
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 2 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Top 10% | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
