Authors
Rasmus Oestergaard Nielsen
Michael Lejbach Bertelsen
Daniel Ramskov
Merete Møller
Adam Hulme
Daniel Theisen
Caroline F. Finch, Edith Cowan UniversityFollow
Lauren Victoria Fortington, Edith Cowan UniversityFollow
Mohammad Ali Mansournia
Erik Thorlund Parner
Document Type
Journal Article
Publication Title
British Journal of Sports Medicine
Medical Subject Headings
Athletic Injuries; Biomedical Research; Humans; Models, Statistical; Physical Conditioning, Human; Research Design; Sports Medicine; Time Factors
ISSN
1473-0480
Volume
53
Issue
1
First Page
61
Last Page
68
PubMed ID
30413422
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
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.
DOI
10.1136/bjsports-2018-099408
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
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.