Suppose you have some big data files to analyse, and you would like to know roughly how long it takes to run the analysis. This is so that in future, if you had to re-run the analysis, you could gauge that it will take long enough to go get a coffee or work on another job while you wait for
Read more
Researchers are increasingly encouraged to implement reproducible research practices in their work. These practices include describing the data collected and used for analysis in detail, clearly reporting the analysis method and results, and sharing the dataset and statistical or analysis code. To determine how well reproducible research practices are implemented, Page and colleagues (2017) investigated their implementation in systematic reviews
Read more
Every day, we are confronted by claims about effects of treatments, many of which are not supported by evidence and are misleading. It is easy to overestimate the benefits of treatments and to underestimate their potential risks, without knowing how to accurately assess claims about treatments. To address these problems, Castle and colleagues developed the Critical thinking and Appraisal Resource
Read more
When a p value that fails to reach a threshold is reported, investigators sometimes imply there is a “trend towards statistical significance”. This interpretation expresses the view that if more subjects had been tested, the p value would have become more significant. Epidemiologists Wood and colleagues examined the probability of how the p value of a treatment effect changes when
Read more
Most sample size calculations for independent or paired samples are performed based on power to detect an effect of a certain size, assuming there’s no effect. Instead, Cumming and Calin-Jageman recommend that readers plan studies to detect precise effects. The 95% confidence interval (CI) indicates precision about effects. Therefore, it is possible to plan studies to detect narrow 95% CIs
Read more
Many studies take repeated observations on subjects. For example, clinical trials record outcomes from subjects before and after treatments, and laboratory studies might record physiological outcomes from the same subjects over time. In a dataframe, when observations from each subject are written on one row and repeated observations are stored as different column variables, we say the data are in
Read more
Scientifically Sound 