This observational study aims to investigate the association between brain type, determined by the second-to-fourth digit (2D:4D) ratio, playing position, and mental toughness among amateur soccer players. A total of 270 licensed amateur soccer players participated in the study. Mental toughness was assessed using the Sports Mental Toughness Questionnaire (SMTQ), while brain type was determined by measuring the 2D:4D digit ratio. The study examines whether mental toughness differs according to brain type and playing position, providing insight into the neuropsychological characteristics of soccer players and their potential relationship with psychological performance.
Who can participate
Age range
16 Years – 40 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Licensed amateur soccer player.
* Aged between 16 and 40 years.
* Currently participating in regular soccer training and competitions.
* Able to understand and complete the Sports Mental Toughness Questionnaire (SMTQ).
* Provided written informed consent prior to participation.
Exclusion Criteria:
* Professional soccer players.
* History of neurological or psychiatric disorders that could affect psychological assessment.
* Upper extremity deformity or injury preventing accurate 2D:4D measurement.
* Incomplete questionnaire or missing study data.
* Declined or withdrew informed consent.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Sports Mental Toughness Questionnaire (SMTQ) Total Score