Evolution in the Use of Statistical Testing in the Field of Orthopedics From 1993 to 2023

Statistical tests are important tools in research as they provide a systematic and objective approach to analyzing data, testing hypotheses, and drawing conclusions. We investigated the application of statistical tests used in articles published in the Journal of Bone and Joint Surgery (JBJS) over the last 30 years. We searched PubMed for JBJS articles published from 1993 to 2023 and randomly sampled 5% of articles from each year. Our inclusion criteria identified a selection of articles for review, and we collected and analyzed variables, including statements of significance, significance level, power calculations, usage of statistical tests and methods, power analysis, and orthopedic subspecialties. Articles were grouped into three 10-year periods, and then analysis of variance, Tukey's honestly significant difference, and chi-square tests were conducted to investigate the changes between decade intervals. Our 5% stratified random sample of JBJS publications yielded 593 unique articles, of which 559 were accessible as full-text articles. Common statistical tests included t-test, chi-squared, and ANOVA. The average number of statistical tests per paper increased from 1993-2002 (n = 0.64) to 2013-2023 (n = 1.25) (p value = 0.0009). Among the articles stating alpha levels (n = 156), 0.05 was most prevalent (94%), with 0.01 and 0.1 less commonly used (3.2% and 1.2%, respectively). Article types varied, with "commentary, editor, forum" being the most common (n = 124), followed by retrospective cohort studies (n = 105). The most frequent power goals were 80% and 90%. In studies reporting power calculations, 34% declared adequate power, 14% admitted insufficient power, and 52% did not disclose adequacy. Statistical test and publication trends varied greatly between orthopedic subspecialties. With the increasing usage of statistical tests in orthopedic research, it is increasingly important for readers to have a strong understanding of statistical analysis. This foundational knowledge will enable critical engagement with literature and aid in the growth of the orthopedic field.