Uncertainty in medical decision making

By | October 21, 2019

“The failure to train doctors about clinical uncertainty has been called “the greatest deficiency of medical education throughout the twentieth century.” Djulbegovic (2004), https://www.bmj.com/content/329/7480/1419 Life is full of uncertainties. In decision making uncertainty means that it is impossible to define future outcomes. Amount of medical information continues to grow exponentially, but uncertainty is still inevitable… Read More »

No evidence of no evidence

By | October 5, 2019

In the null hypothesis significance testing framework, failure to reject the null is never evidence in support of null. However, it is extremely common that failure to reject the null, ie. getting a p-value larger 0.05 is interpreted as “no difference” or “no evidence”. As many experts have said, “absence of evidence is not evidence… Read More »

Industry based evidence synthesis

By | August 28, 2019

In 2017, me and colleagues published both a literature and registry based analysis of use of metal-on-metal hip replacements. This study, titled Lack of evidence—the anti-stepwise introduction of metal-on-metal hip replacements, was a hypothesis-driven study since at that time it seemed that the use of ASR hip replacements was not that evidence based but mainly… Read More »

Declining incidence of MoM revision surgeries

By | July 22, 2019

Our recent study investigating annual trends of revision surgeries in patients with MoM hip replacements was recently published in the Journal of Arthroplasty (www). Here is the GrAbstract of the study: This study is of great importance because it is the largest non-registry based study investigating what sort of trends the number of revision surgeries… Read More »

Post-hoc power – Alone in the universe

By | July 5, 2019

Prologue Firstly, it is important to describe what post-hoc power really means. Post-hoc power is the power of the test using effect size observed and sample size used in the study. For this reason post-hoc power is often labeled as observed power. If for any experiment the effect size, parameter estimates and sample size is… Read More »

Metal-on-metal hips on the Gartner Hype Cycle

By | May 8, 2019

This post describes an adaptation of Gartner Hype Cycle on metal-on-metal hip replacements. It is very unlikely that MoM hip replacements will achieve the “Plateau of Productivity“. Therefore two other later stages are proposed with annotations. Reference 1. Harris WH. Osteolysis and particle disease in hip replacement. A review. Acta Orthop Scand. 1994 Feb;65(1):113-23. 2.… Read More »

Increasing incidence of quadriceps tendon rupture

By | April 16, 2019

Our study about increasing incidence of surgically treated quadriceps tendon ruptures was just published in the Knee Surgery, Sports Traumatology, Arthroscopy. At this moment it is in Open Access format so full-text is freely available. Below is the grabstract, ie. graphical abstract, of our study. In our study we write “There is no evidence of… Read More »