Abstract
BACKGROUND: ‘How much change in training load is too much before injury is sustained, among different athletes?’ is a key question in sports medicine and sports science. To address this question the investigator/practitioner must analyse exposure variables that change over time, such as change in training load. Very few studies have included time-varying exposures (eg, training load) and time-varying effect-measure modifiers (eg, previous injury, biomechanics, sleep/stress) when studying sports injury aetiology.
AIM: To discuss advanced statistical methods suitable for the complex analysis of time-varying exposures such as changes in training load and injury-related outcomes.
CONTENT: Time-varying exposures and time-varying effect-measure modifiers can be used in time-to-event models to investigate sport injury aetiology. We address four key-questions (i) Does time-to-event modelling allow change in training load to be included as a time-varying exposure for sport injury development? (ii) Why is time-to-event analysis superior to other analytical concepts when analysing training-load related data that changes status over time? (iii) How can researchers include change in training load in a time-to-event analysis? and, (iv) Are researchers able to include other time-varying variables into time-to-event analyses? We emphasise that cleaning datasets, setting up the data, performing analyses with time-varying variables and interpreting the results is time-consuming, and requires dedication. It may need you to ask for assistance from methodological peers as the analytical approaches presented this paper require specialist knowledge and well-honed statistical skills.
CONCLUSION: To increase knowledge about the association between changes in training load and injury, we encourage sports injury researchers to collaborate with statisticians and/or methodological epidemiologists to carefully consider applying time-to-event models to prospective sports injury data. This will ensure appropriate interpretation of time-to-event data.
Keywords
Athletic Injuries, Biomedical Research, Humans, Models, Statistical, Physical Conditioning, Human, Research Design, Sports Medicine, Time Factors
Document Type
Journal Article
Date of Publication
1-1-2019
ISSN
1473-0480
Volume
53
Issue
1
PubMed ID
30413422
Publication Title
British Journal of Sports Medicine
Publisher
BMJ Publishing Group
School
School of Medical and Health Sciences / Australian Centre for Research into Injury in Sport and its Prevention (ACRISP)
RAS ID
28825
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
First Page
61
Last Page
68
Comments
Nielsen, R. O., Bertelsen, M. L., Ramskov, D., Møller, M., Hulme, A., Theisen, D., ... & Parner, E. T. (2019). Time-to-event analysis for sports injury research part 1: time-varying exposures. British Journal of Sports Medicine, 53(1), 61-68.
Available here.