MATERIALS.METHODS.VALIDATION.

Match exposure and practical use.

A 2026 synthesis reported 10.98 concussions per 1,000 rugby-union match-player-hours and 0.34 per 1,000 training-player-hours. The pooled estimates combine studies with different populations, rugby-union formats and clinical or protocol-based assessment methods. Match-player-hours sum exposure across players; the rate is not an individual player’s probability. De Sousa-De Sousa et al. (2026)

A UK online survey recorded regular match headgear use in 195 of 545 respondents (36%) in March–June 2016. Respondents in this self-selected UK sample described discomfort, heat and restricted senses as barriers. Barnes et al. (2017)

Three findings behind the design brief.

The RFU’s 2018–19 professional surveillance report states that 21% of players sustained at least one match concussion. The programme monitored 763 registered squad players across all 12 Premiership clubs, including first-team academy players. The report does not give the unique-player count behind the 21% statement. Its 166 match concussions are injury events; its 20.4 per 1,000 match hours is an incidence rate. RFU season report / 2018–19, pp. xii and xxxii

In Barnes and colleagues’ UK survey, 124 of 185 previous but non-regular headgear wearers (67%, rounded) said they had tried headgear but did not like wearing it. This is a subgroup of the 545-person survey conducted in March–June 2016, not all respondents or all rugby players. Barnes et al. (2017), Headgear use and injury

Knight and colleagues surveyed parents and guardians of under-16 and under-18 female rugby players in England in March–August 2024. Among 285 eligible respondents, Table 2 reports 76% selecting “Never” for their child’s scrum-cap use. The study contacted 1,062 parents/guardians and reports a 27% response rate; most respondents’ children played at regional level. These are parent/guardian reports in a selected sample, rather than direct observation or a national wearing rate. This finding does not establish the reasons for non-use. Knight et al. (2026), Table 2

World Rugby’s 2026–31 Strategic Plan reports more than 2.2 million women and girls playing worldwide. The figure covers participation across the sport, including non-contact formats.

Mechanical performance and injury outcomes

Laboratory testing measures how protective structures respond to impacts, including linear and rotational head acceleration. Clinical research is required to establish whether mechanical differences translate into changes in diagnosed injury rates. Concussion can follow forces transmitted from head, neck or body contact. Amsterdam concussion consensus (2023)

Instrumented-mouthguard research in elite men’s and women’s rugby examines both linear and angular head acceleration. Thresholds, event definitions and populations affect interpretation; acceleration alone does not diagnose concussion. Instrumented mouthguard tackle study (2024)

Concussion in professional training.

In a study of men’s English Premiership training across the 2016/17–2023/24 seasons, the reported concussion incidence was 0.23 per 1,000 training player-hours (95% confidence interval 0.22–0.29). The mean time absent per training concussion was 18 days (95% confidence interval 15–21). These are professional men’s training data, not match, youth or women’s rates. Training concussion surveillance (2026)

Clinical studies of padded headgear.

A youth rugby trial did not demonstrate concussion reduction with the tested padded headgear; low wearing adherence limits interpretation. Youth rugby headgear trial (2009) A later professional men’s cohort also found no protective association for suspected head injury assessments. Its observational design cannot establish causation, and suspected assessments are not all confirmed concussions. Professional men’s headgear cohort (2025/26)

Controlled headform testing

Stitt and colleagues tested selected soft headgear on a Hybrid III headform and neck, varying impact speed, orientation and surface angle. They measured linear and rotational acceleration, finding differences between the tested products. The measured differences concern those products under the specified laboratory conditions. Stitt et al. (2022)

Repeated exposure and long-term health.

Repetitive head impacts warrant investigation. The Amsterdam consensus distinguishes postmortem CTE neuropathology from clinical diagnoses and identifies uncertainty around prevalence, causation and individual risk. It does not support deriving CTE risk from a single impact measure. Amsterdam concussion consensus (2023)

D03 has not demonstrated prevention of concussion, brain injury or CTE. Product development and safety information ↗