Title: Physical Activity, Exercise, and Sports Medicine
Dr. Éanna Falvey
Summary of main findings 3
3.1 General Considerations 4
3.2 Population 5
3.3 Data Collection 5
3.4 Study Design 6
3.5 Validity of Results 7
The 5th Consensus
Statement on Concussion in Sport first defines sport related concussion broadly
as, “…representing the immediate and transient symptoms of traumatic brain
injury.1 It is further defined as “…a traumatic brain injury
induced by biomechanical forces.”1 Concussion results in an
impairment of neurological function with a range of clinical symptoms that may
or may not include loss of consciousness.1
Awareness of concussion has increased, however the nuances of the injury
are poorly understood.2 Estimates show that those affected by
concussion in the U.S. range from 1.6 to 3.8 million annually.2 Concussion
is a very topical area that has garnered much media attention of late.34
It is unsurprising as it is linked to chronic traumatic encephalopathy,
neurodegenerative disease and long-term cognitive deficits.5 6 78
Rugby is a high intensity sport that is linked to head injury, with concussion
“…commonly reported during match play.”9 It is imperative that
those involved in the game; players, coaches, referees, and medical staff have
a comprehensive knowledge of concussion injury so that concussion can be
prevented, recognised and managed.
Pitch side assessment is
a “key component” in evaluating concussion injury.1 The Sport Concussion
Assessment Tool (SCAT-5) has been developed, informed by evidence based
research, for recognising concussion symptoms, assessing players, and for
return to play guidelines.1 There has been research into player’s
knowledge and attitudes as well as coaches, parents, and referees.101112
Research has focused on knowledge of rugby coaches and referees in the
professional game, rather than the amateur game.13 The aim of this
critical review is to assess a study which measures concussion knowledge in
coaches and referees involved in the amateur game in Welsh Rugby Union (WRU) .14
2. Summary of main
cross-sectional study gathered information from 333 coaches and 283 referees
involved in amateur WRU, in both youth and adult clubs. Its main findings show
that there is a high standard of knowledge among coaches and referees with
regards concussion symptom recognition. The mean score for concussion symptom
recognition was 18.6 out of 21 (95% CI 18.4 to 18.7). The mean score for return
to play guidelines and consequences of concussion knowledge were 11 out of 16
(95% CI 11.5 to 11.8) and 1 out of 6 (95% CI 0.9 to 1.1) respectively. There
are clear discrepancies in knowledge regarding the prevention of concussion and
the return to play guidelines. Knowledge in these areas were considered poor. Further,
67% of participants held an incorrect belief that headgear protects against
concussion. There were no significant differences of knowledge between the two
groups, coaches and referees.13
authors outline that concussion management within the amateur game in Wales
must be improved upon and suggest a “multi-faceted educational intervention.”
The article is clearly outlined and discussion and arguments in favour of
further education well-structured. The authors take a balanced approach,
outlining the strengths and limitations of their study throughout. I will further
discuss these strengths and limitations below.14
This study has a clear
aim in assessing knowledge and experience of concussion among WRU coaches and
referees involved in the amateur game. The authors outline clearly the
necessity for such a study by highlighting the “steadily increasing” incidence
of concussion within rugby over the last decade.14 There has been
evidence of under-reporting of concussion injury by athletes.1516
Therefore the recognition by referees, coaches and medical staff is imperative
as “…diagnosis currently hinges on the subjective identification of the
clinical signs and symptoms.”14
The authors outline that
only two previous studies have looked at concussion knowledge in referees.1718
Rule 23 of the World Rugby Union Laws state that if a player has a suspected
concussion, the player “…must be immediately and permanently removed from the
playing area.”19 The referee may decide under rule 21 and 22 that
the player is injured and must leave the field to be medically examined.19
As an impartial arbiter on the pitch, the referees’ knowledge and
management of concussion needs to be of a high standard. Assessing the
knowledge of referees in this study will contribute significantly to the body
of knowledge on concussion.
The findings of this
study will help inform guidelines and education with regard concussion.
Further, highlighting of these issues and raising awareness of concussion will
contribute to the prevention, recognition, and management of head injury in
sport. Increasing the knowledge of key participants in sport will aid the
medical profession in providing rapid recognition and management of symptoms.
This article has contributed to my own knowledge of concussion. The article has
also highlighted to me some key gaps in knowledge of coaches and referees which
will be worth considering when participating in sports as well as when dealing
with those involved in sport in my future career.
I will now critically
assess this paper in the four following areas; population, data collection,
study design and validity of results.
Inclusion and exclusion
criteria are not explicitly defined but the population is defined as all known
qualified rugby union coaches (n=1,843) and referees defined as ‘all eligible
participants’ (n=420). While it is likely that referees are registered with the
WRU, ‘all eligible participants’ could be construed as ambiguous and a clear
inclusion or exclusion criteria is preferable. A possible issue with each population
is that in the amateur set-up, there may be some unregistered participants
involved. A way around this could be to contact clubs to get contact details of
all those involved in coaching and refereeing. The number of registered rugby
players in Wales is 83,120.20 The ratio of 45:1, players:coaches
appears to be a reasonable size.
A difficulty encountered
by the authors of this research was the response rate. A total of 621
questionnaires were returned. 19% response rate from coaches (n=337) and 68%
response rate from referees (n=284). The authors acknowledged that the poor
response rate from coaches hindered the validity of the data. However it is
worth noting that compared to similar studies, this is the largest sample size
of rugby coaches surveyed with respect to concussion knowledge and experience.
Previous studies have had samples of 12 and 267 coaches respectively.1318
Future studies should aim to improve the sample size by introducing measures to
improve response rates.
The authors’ methods of
data collection involved accessing emails from governing bodies, the WRU
coaching development department for coaches and the WRU’s National Match
Official’s Manager. Emails were sent out with a hyperlink to access the
questionnaire. Consent was required from all responders and those who did not
consent were not able to engage in the survey. There have been concerns about
reduced response rate to email questionnaires.21 However as the
population becomes more ‘internet savvy’ studies suggest that it is the more
effective mode of data collection compared to postal survey.22 Some
considerations may be that not all people check their emails regularly, or many
people will disregard an email based survey due to lack of time. To improve
email response the authors could consider offering an incentive for completion or
offer paper-based questionnaires delivered through club management.
The authors categorised
the questionnaire as confidential rather than anonymous. This could be a
further reason for low response rates from coaches. While the authors state
that it was made clear that the responses were not traceable, it is possible
that coaches are afraid that their responses could traceable back to them
through personal postcode. There also is an issue of selection bias regarding responders.
The responders to the survey may be those who are more likely to engage in safe
practice and conscious of improving their education with regards to concussion.
This was a cross-sectional
study of rugby coaches and referees in the amateur welsh rugby union. Ethical
approval was obtained from the Cardiff School of Sport’s research ethics
committee. Some of the benefits of a cross-sectional study include that it is easy
to complete, cheap and fast. It can also measure multiple factors
simultaneously. For this topic, it is the appropriate means of gathering
information. Several other studies assessing concussion experience and
knowledge have also used cross-sectional study design.1011121314
Some limitations of this design is that it is susceptible non-response bias and
the sample size needs to be sufficiently large to determine prevalence. These limitations
have been outlined above.
The self-reported nature
of the study is one of its primary limitations. There may be selection bias in
terms of those who responded but also recall bias in terms of how the questions
were answered. Recall bias may be evident regarding results on removing a
player with suspected concussion from play. 93% of coaches reported they would
remove a player with suspected concussion from play immediately as per guidelines.1
However 40% of coaches reported witnessing another coach pressure a potentially
concussed player to stay on the pitch. 28% of coaches reported witnessing
medical staff being pressured into allowing a potentially concussed player stay
on the pitch. It is also possible that the 81% of non-responding coaches could
be less compliant with concussion measures and these non-responders may provide
an explanation for the discrepancy in results.
The questionnaire was
based on a paper-based survey and adapted for an email-based survey. The
questionnaire instrument was not validated. This was acknowledged, and a pilot
study was conducted to test the instrument. Each questionnaire was adapted with
specific questions relevant to coaches and referees but questions on recognising
symptoms of concussion, consequences of concussion, return to play guidelines,
and headgear usage were identical. The questionnaire was included in the study
and a reference to the original questionnaire it was based on also provided.
These factors help in ensuring the study is repeatable.
Validity of results
The results were clearly
outlined in the results section. A graph outlined the results of coaches versus
referees in recognising the true symptoms of concussion. Knowledge of return to
play guidelines would have been well illustrated in a graph but were not provided.
The conclusions drawn by the authors reflect the analysis carried out and unequivocally
state limitations experienced. The primary concern with regards validity of
results is the poor response rate from the coaches’ population (19%). The
authors of this study highlight that this is a concern and acknowledge that the
results of the study with regards coaches may be compromised as a result. As discussed
above, subsequent studies should develop measures to increase the response rate.
The authors outline the
need for further research. It is recommended that the same questions on
recognition of symptoms, prevention and return to play knowledge should be applied
to other groups – medics and physios involved with teams, players, and parents
of youth players. Validation of the survey instrument would provide further strength
to the validity of results.
The overall validity of
this study based on the EBL Critical Appraisal checklist is 86%.23
As this is greater than 75%, I can state that the study is valid. Overall this
article presented a clear and structured presentation of this research and a
balanced and informed discussion of their results. The primary weakness of the
study is the poor response rate of coaches. The population score was 67%
according to the EBL guidelines. A score of less than 75% indicates that the
reliability of data relating to this area is poor. The authors were aware of
these weaknesses and highlighted their concerns regarding these results.
Understandably there are
concerns regarding the long term effects of concussion, particularly in the
wake of the much reported experience of NFL players and long term effects of concussion.242526
A protocol for assessing long term effects of concussion in retired rugby union
players has been established in the UK.27 Further studies
confirming long term effects will undoubtedly support the importance of
preventing, recognising, and managing concussion in rugby.
By completing this study,
the authors have contributed to raising awareness of concussion in sport. This
study provides evidence that further education in concussion is required for
coaches and referees in rugby. The authors provide a clear framework for the
study to be repeated in other regions and across other sports where concussion
is a concern.
1 McCrory P, Meeuwisse
W, Dvorak J, Aubry M, Bailes J, Broglio S, Cantu RC, Cassidy D, Echemendia RJ,
Castellani RJ, Davis GA. Consensus statement on concussion in sport—the 5th
international conference on concussion in sport held in Berlin, October 2016.
Br J Sports Med. 2017 Apr 26:bjsports-2017.
M. Traumatic brain injury in 2017: exploring the secrets of concussion. The
Lancet Neurology. 2018 Jan 31;17(1):13-5.
in sport: 72 children attend Dublin hospital with head injuries from sport in
just six months, Irish Independent, 7th July 2017 accessed at https://www.independent.ie/irish-news/concussion-in-sport-72-children-attend-dublin-hospital-with-head-injuries-from-sport-in-just-six-months-35999695.html
in sport: Five sports gather to discuss head-injury prevention, BBC News, 20th
July 2017 accessed at http://www.bbc.com/sport/rugby-union/40675605
5 Broglio SP, Moore RD,
Hillman CH. A history of sport-related concussion on event-related brain
potential correlates of cognition. International Journal of Psychophysiology.
2011 Oct 1;82(1):16-23.
6 Tagge CA, Fisher AM,
Minaeva OV, Gaudreau-Balderrama A, Moncaster JA, Zhang XL, Wojnarowicz MW,
Casey N, Lu H, Kokiko-Cochran ON, Saman S. Concussion, microvascular injury,
and early tauopathy in young athletes after impact head injury and an impact
concussion mouse model. Brain. 2018 Jan 18.
7 Stein TD, Alvarez VE,
McKee AC. Concussion in chronic traumatic encephalopathy. Current pain and
headache reports. 2015 Oct 1;19(10):47.
8 Lehman EJ, Hein MJ,
Baron SL, Gersic CM. Neurodegenerative causes of death among retired National
Football League players. Neurology. 2012 Nov 6;79(19):1970-4.
9 Gardner AJ, Iverson
GL, Williams WH, Baker S, Stanwell P. A systematic review and meta-analysis of
concussion in rugby union. Sports medicine. 2014 Dec 1;44(12):1717-31.
10 Cusimano MD, Zhang
S, Topolovec-Vranic J, Hutchison MG, Jing R. Factors affecting the concussion
knowledge of athletes, parents, coaches, and medical professionals. SAGE open
medicine. 2017 Mar 3;5:2050312117694794.
11 O’Connell E, Molloy
MG. Concussion in rugby: knowledge and attitudes of players. Irish Journal of
Medical Science (1971-). 2016 May 1;185(2):521-8.
12 Delahunty SE,
Delahunt E, Condon B, Toomey D, Blake C. Prevalence of and attitudes about
concussion in Irish schools’ rugby union players. Journal of school health.
2015 Jan 1;85(1):17-26.
13 Fraas MR, Coughlan
GF, Hart EC, McCarthy C. Concussion knowledge and management practices among
coaches and medical staff in Irish professional rugby teams. Irish Journal of
Medical Science (1971-). 2015 Jun 1;184(2):425-30.
14 Griffin SA, Ranson
C, Moore I, Mathema P. Concussion knowledge and experience among Welsh amateur
rugby union coaches and referees. BMJ open sport & exercise medicine. 2017
15 Conway FN, Domingues
M, Monaco R, Lesnewich LM, Ray AE, Alderman BL, Todaro SM, Buckman JF.
Concussion Symptom Underreporting Among Incoming National Collegiate Athletic
Association Division I College Athletes. Clinical journal of sport medicine:
official journal of the Canadian Academy of Sport Medicine. 2018 Jan.
16 Meier TB, Brummel
BJ, Singh R, Nerio CJ, Polanski DW, Bellgowan PS. The underreporting of
self-reported symptoms following sports-related concussion. Journal of science
and medicine in sport. 2015 Sep 1;18(5):507-11.
17 King D, Hume P,
Clark T. First-aid and concussion knowledge of rugby league team management,
administrators and officials in New Zealand. NZJ Sports Med. 2010
18 White PE, Newton JD,
Makdissi M, Sullivan SJ, Davis G, McCrory P, Donaldson A, Ewing MT, Finch CF.
Knowledge about sports-related concussion: is the message getting through to
coaches and trainers?. Br J Sports Med. 2013 Sep 14:bjsports-2013.
19 Laws of the Game,
Rugby Union, accessed at http://laws.worldrugby.org/?law=3=EN
20 World Rugby Website
accessed at https://www.worldrugby.org/development/player-numbers?lang=en
21 Sebo P, Maisonneuve
H, Cerutti B, Fournier JP, Senn N, Haller DM. Rates, delays, and completeness
of general practitioners’ responses to a postal versus web-based survey: a
randomized trial. Journal of medical Internet research. 2017 Mar;19(3).
22 McMaster HS,
LeardMann CA, Speigle S, Dillman DA. An experimental comparison of web-push vs.
paper-only survey procedures for conducting an in-depth health survey of
military spouses. BMC medical research methodology. 2017 Dec;17(1):73.
23 Glynn L. A critical
appraisal tool for library and information research. Library Hi Tech. 2006 Jul
24 Mez J, Daneshvar DH,
Kiernan PT, Abdolmohammadi B, Alvarez VE, Huber BR, Alosco ML, Solomon TM,
Nowinski CJ, McHale L, Cormier KA. Clinicopathological evaluation of chronic
traumatic encephalopathy in players of American football. Jama. 2017 Jul
25 Alosco ML, Tripodis
Y, Jarnagin J, Baugh CM, Martin B, Chaisson CE, Estochen N, Song L, Cantu RC,
Jeromin A, Stern RA. Repetitive head impact exposure and later-life plasma
total tau in former National Football League players. Alzheimer’s &
Dementia: Diagnosis, Assessment & Disease Monitoring. 2017 Jan 1;7:33-40.
26 Amen DG, Willeumier
K, Omalu B, Newberg A, Raghavendra C, Raji CA. Perfusion neuroimaging
abnormalities alone distinguish National Football League players from a healthy
population. Journal of Alzheimer’s Disease. 2016 Jan 1;53(1):237-41
27 Gallo V, McElvenny
D, Hobbs C, Davoren D, Morris H, Crutch S, Zetterberg H, Fox NC, Kemp S, Cross
M, Arden NK. BRain health and healthy AgeINg in retired rugby union players,
the BRAIN Study: study protocol for an observational study in the UK. BMJ open.
2017 Dec 1;7(12):e017990.