Problems in all-cause revision analyses in total joint replacement research?

I had a chance to collaborate with Nordic Arthroplasty Register Association in a study published in the Acta Orthopaedica last year. Study was titled “The effect of fixation type on the survivorship of contemporary total knee arthroplasty in patients younger than 65 years of age: a register-based study of 115,177 knees in the Nordic Arthroplasty […]

What sort of improvement we need in our research?

This is not a new study but I came across to this study by Brophy et al. titled “Update on the Methodological Quality of Research Published in The American Journal of Sports Medicine“. They concluded: Despite a dramatic increase in the number of published articles, the research published in AJSM shifted toward more prospective, randomized, […]

Do we have bigger problems than possible lowering the threshold of statistical significance

Evans et al. published following study in the Arthroscopy Journal “The Potential Effect of Lowering the Threshold of Statistical Significance From P < .05 to P < .005 in Orthopaedic Sports Medicine”. This caught my attention since these authors published similar article in another journal in 2019 titled “Effects of a proposal to alter the statistical significance threshold on […]

Larger sample sizes in orthopaedics?

My recent research efforts have concerned metaresearch on orthopaedic RCTs. We have argued many aspects in those studies and in their quality. One major aspect is the sample size which still remains very small. In our recent paper we investigated orthopaedic RCTs published in 2016 and 2017 and we reported: The median numbers of patients […]

Exploratory or confirming study?

Methodology is hard. And making valid inferences is very hard. With regard to these topics, orthopaedic research is not very different to other field in medicine. It means that misconceptions, misunderstandings and flawed approaches are prevalent also in our field. American Journal of Sports Medicine published recently two papers which both made a quite common, […]

No evidence of no evidence

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 […]