Sample Size, Sample Characteristics, and Measurement Practices in Jump and Sprint Performance Research in Sports Science

This research has a number of aims; first, we aim to describe the typical sample sizes used in experimental research, using within- and between-subjects designs, assessing sprint and jump performance across gender, competitive level, and year of publication. Second, we aim to determine if year of publication or gender of sample participants affect the observed samples sizes. Third, we aim to describe the type of sample size justifications provided, and whether the inclusion of a justification has changed over time. Fourth, we aim to describe the typical levels of attrition in experimental studies and whether attrition is considered within a sample size justification. Fifth, we aim to describe how often small sample sizes, low statistical power, and poor precision are identified as issues or limitations within the published research. Further, we aim to determine how often precision estimates are reported around effect sizes and the most common type of precision estimates. Finally, we aim to identify the most common sprint and jump tests and test outcomes used within experimental research, as well as the most common practices around the number of trials used and how they are reduced.