Here is the design of a clinical trial:

Official Title: Wearables in Rugby Union: A Protocol for Multimodal Digital Sports-related Concussion Assessment

Included conditions:
- Concussion, Brain
- Sports Injury

Study Armgroups:
- {'label': 'University-level and amateur rugby players', 'description': 'University-level and amateur rugby players will be recruited and assessed (motor, visual and symptom assessment) over one season ( June 2021 to August 2022).\n\nParticipants will be stratified according to gender (males n≈100, and females n≈100). Although the number of SRC that will be observed during the season is not known, the investigators will compare a number of head injuries/SRC to the results from cohort baseline testing. Participants that do not sustain a concussion will also have follow up testing at the end of the season.'}

Interventions:

Primary Outcomes:
- {'measure': 'Step time (mean ± standard deviation)', 'description': 'Altered free-living, quality-based gait/walking patterns measured by digital intertial wearable', 'timeFrame': 'Participants diagnosed with SRC will be asked to attend a laboratory session/free living assessment at the following subsequent time frames post injury; within 72 hours post, 7-14 days post, within 30 days and 3-6 months'}
- {'measure': 'Stance time (seconds, mean ± standard deviation)', 'description': 'Altered free-living, quality-based gait/walking patterns measured by digital intertial wearable', 'timeFrame': 'Participants diagnosed with SRC will be asked to attend a laboratory session/free living assessment at the following subsequent time frames post injury; within 72 hours post, 7-14 days post, within 30 days and 3-6 months'}
- {'measure': 'Stride time (seconds, mean ± standard deviation)', 'description': 'Altered free-living, quality-based gait/walking patterns measured by digital intertial wearable', 'timeFrame': 'Participants diagnosed with SRC will be asked to attend a laboratory session/free living assessment at the following subsequent time frames post injury; within 72 hours post, 7-14 days post, within 30 days and 3-6 months'}
- {'measure': 'Swing time (seconds, mean ± standard deviation)', 'description': 'Altered free-living, quality-based gait/walking patterns measured by digital intertial wearable', 'timeFrame': 'Participants diagnosed with SRC will be asked to attend a laboratory session/free living assessment at the following subsequent time frames post injury; within 72 hours post, 7-14 days post, within 30 days and 3-6 months'}
- {'measure': 'Stride length (cm, mean ± standard deviation)', 'description': 'Altered free-living, quality-based gait/walking patterns measured by digital intertial wearable', 'timeFrame': 'Participants diagnosed with SRC will be asked to attend a laboratory session/free living assessment at the following subsequent time frames post injury; within 72 hours post, 7-14 days post, within 30 days and 3-6 months'}
- {'measure': 'Stride velocity (cms-1), mean ± standard deviation)', 'description': 'Altered free-living, quality-based gait/walking patterns measured by digital intertial wearable', 'timeFrame': 'Participants diagnosed with SRC will be asked to attend a laboratory session/free living assessment at the following subsequent time frames post injury; within 72 hours post, 7-14 days post, within 30 days and 3-6 months'}

Please estimate the sample size based on the assumption: 
Confidence level of 95% (α = 0.05, Z-value = 1.96), margin of error of 0.075 (7.5%).
Sample size calculation
        The sample size calculation is based sample sizes from previous paper examining multimodal assessment, ~200 [18,35]. To determine the appropriate sample size (SS) for estimating the proportion of players we used the following formula (Eq 1) as previously described.
        
SS=(Zâscore)2ÃproportionÃ(1âproportion)/(marginoferror)2
(1)

        For a confidence level of 95%, Î± is 0.05 and the corresponding Z-value is 1.96. The sample proportion is unknown. We chose the number 0.50 (50%) because it takes the maximum spread into account. Consensus about the margin of error was achieved by joint discussion of the research group; a margin error of 0.075 (7.5%) was accepted. For a population size of 200 and a confidence level of 95%, Î± is 0.05 and the corresponding z-value is 1.96. Therefore, in total, 200 patients will be enrolled in the study to reach the necessary sample size.