Descriptive numerical summary
The electronic searches yielded 70,242 potentially eligible citations. After de-duplication, 63,302 citations underwent title and abstract screening, leaving 720 articles which were reviewed for eligibility. After full text review, 406 articles were retained. Bibliographic and citation searching resulted in 5 additional studies being identified, with a final number of 411 studies being included in the review. The flowchart showing the selection process from identification to final inclusion is depicted in Figure 1.
General characteristics of included studies
Of the 411 included studies, 349 were primary studies and 62 were reviews. The key characteristics of both types of studies are summarised in Tables 1 and 2.
Table 1 Key characteristics of included studies: Primary studies (n=349)
Criterion
|
Characteristic
|
Number of studies (%)
|
Study design/Publication type
|
Experimental
|
123 (35.2)
|
Observational
|
116 (33.2)
|
Descriptive
|
25 (7.1)
|
Discussion paper/report
|
58 (16.6)
|
Qualitative
|
19 (5.4)
|
Mixed-methods
|
8 (2.5)
|
Country of origin of study
|
LMIC
|
65 (18.6)
|
HIC
|
284 (81.4)
|
Intervention type
|
Primary prevention
|
249 (71.3)
|
Secondary prevention
|
57 (16.3)
|
Tertiary prevention
Multiple levels of prevention
|
40 (11.5)
3 (0.9)
|
Year of publication
|
1974-1983
|
3 (0.9)
|
1984-1993
|
24 (6.9)
|
1994-2003
|
51 (14.6)
|
2004-2013
|
114 (32.7)
|
2014-2019
|
157 (44.9)
|
Population
|
Adults only
|
68 (19.5)
|
Children only
|
72 (20.6)
|
Adults and children
|
209 (59.6)
|
Setting
|
National
|
76 (21.8)
|
State/Province
|
114 (32.7)
|
City/town/village
|
84 (24.1)
|
Neighbourhood/Home/School/Health-facility/ Workplace/Community
|
59 (16.8)
|
Not reported
|
16 (4.6)
|
Table 2 Key characteristics of included studies: Reviews (n=62)
Criterion
|
Characteristic
|
Number of studies (%)
|
Review type
|
Systematic review
|
37 (59.7)
|
Meta-analysis
|
8 (12.9)
|
Literature review
|
15 (24.2)
|
Scoping review
|
2 (3.2)
|
Country of origin of included primary studies
|
LMIC
|
5 (8.1)
|
HIC
|
42 (67.7)
|
LMIC and HIC
|
15 (24.2)
|
Intervention type
|
Primary prevention
|
41 (66.1)
|
Secondary prevention
|
3 (4.8)
|
Tertiary prevention
|
18 (29.1)
|
Year of publication
|
1974-1983
|
-
|
1984-1993
|
-
|
1994-2003
|
8 (12.9)
|
2004-2013
|
22 (35.5)
|
2014-2019
|
32 (51.6)
|
Population
|
Adults only
|
9 (14.5)
|
Children only
|
5 (8.1)
|
Adults and children
|
48 (77.4)
|
Setting
|
National
|
8 (12.9)
|
State/Province
|
1 (1.7)
|
City/town/village
|
10 (16.1)
|
Neighbourhood/Home/School/Health-facility/ Workplace/Community
|
11 (17.7)
|
Multiple
|
5 (8.1)
|
Not reported
|
27 (43.5)
|
Primary Studies
The majority of the primary studies were from HICs, with less than 20 percent of studies from LMICs. Figure 2 shows a map of the distribution of studies, where many came from three countries-United States of America (USA), United Kingdom (UK) and Australia. Most LMICs gave rise to 6 or fewer publications.
Figure 3 depicts the distribution of interventions and strategies over time in both HICs and LMICs. Most of the studies emerged after the 1990s, both in HICs and LMICs, focussing on primary prevention of neurotrauma, which accounted for nearly three-quarters of the primary studies.
Reviews
For the reviews, nearly three-quarters (72.6%) were systematic reviews and/or meta-analyses. Most reviews were published after 2000. Primary preventative interventions and strategies were reviewed in 41 papers (66.1%), 18 reviewed tertiary (29%), and only three papers reviewed secondary approaches.
Most of the primary papers in the reviews came from HICs (67.7%) with only 5 reviews from LMICs alone. Fifteen reviews (24.1%) included papers from both HICs and LMICs. The majority of the reviews described interventions targeting adults and children, and did not report the setting.
Strategies and interventions
PRIMARY STUDIES
A total of 349 papers were included in this review. The individual strategies and interventions in each category for primary and secondary prevention with the accompanying publication information can be found in Additional file 4.
Primary prevention
252 papers described primary preventative strategies and interventions. All these are categorised and summarised in Table 3. Some studies are included more than once within the results as they discussed more than one strategy or intervention.
[insert Table 3]
Personal safety/protective equipment
Fifty-eight papers explored the use of various personal safety or protective equipment against neurotrauma or road traffic collisions. Three-quarters of the studies came from HICs. Most of the papers were on helmet use and were from both HICs and LMICs. Although most of the studies discussed helmets in relation to road safety, some examined its use in sports, combat and for work safety. All these non-road safety papers on helmet use were from HICs.
Similarly, seat belt use, child car restraints and conspicuity equipment (e.g. high visibility jackets or tapes) were also described in both HIC and LMIC papers. One HIC study discussed other protective sports equipment aside from helmets [45].
The setting for this strategy ranged from cities or rural areas to state and nationwide.
Education/training/awareness-raising
This was described in 48 papers, majority of which were from HICs. The most common type was road safety education or training for various road users. This included driver or motorcycle rider education or training, and pedestrian safety education. One study from an LMIC described a peer educational programme where workers were educated on road safety to be road safety ambassadors in industrial and community settings [46]. Two HIC studies described education of parents on issues surrounding child safety seat use [47,48]. As for other causes of neurotrauma, five HIC studies explored education of parents and nurses on abusive head trauma in infants and young children[49-53].
For sports injuries, two studies, one from an LMIC and the other from a HIC, discussed training and education of athletes and coaches to reduce neurotrauma from rugby and football respectively [54,55].
Materials and methods used for education or training included lectures, demonstrations, videos/DVDs, simulation, quizzes, mobile applications, manuals and worksheets. Another common approach, found predominantly in HICs was campaigns. Most of these campaigns involved media activities to raise awareness about road safety. Two of these were organised at a school-level, both from HICs. Three studies from HICs also discussed campaigns to raise awareness on abusive head trauma in infants.
Most of the interventions took place within the community, both for HICs and LMICs, except for media campaigns which were usually carried out at a National or State level.
Legislation/policy
There were 96 papers which studied different legislation and policies for the prevention of RTCs and neurotrauma. Over 80 percent of papers were from HICs, where more than half discussed Graduated driver licensing system (GDLS) and helmet laws or policies (GDLS is a system designed to allow new drivers to develop their driving skills and experience in well-defined stages [56]). Although the majority of the LMIC studies were also on the helmet laws, only two looked at GDLS [56, 57]. Other policies and legislation found in both LMICs and HICs were on seatbelt and child passenger safety, drink-driving, speeding, cell-phone or texting bans and general road safety.
HIC studies assessed policies and legislation surrounding vehicle roadworthiness, road safety at work, road safety audit, fitness to drive and licensing restrictions, congestion charging schemes, traffic signs or symbols, crossing guards, vehicle and road user conspicuity, and rewards for safe driving or reporting unsafe driving.
Most of these strategies were implemented either at a national or state-wide level, although some were carried out at the workplace.
Enforcement
Thirty-five references examined enforcement strategies and interventions, with only 9 from LMICs. These LMIC studies focussed on traffic policing or patrolling and enforcement of traffic laws, as well as on penalty systems for errant road users. Similar interventions were described in studies from HICs, but the majority described photo enforcement programmes through speed cameras and red light running cameras. One study looked at a school bus stop-arm camera, which cited drivers who would illegally pass a stopped school bus [58]. Both HIC and LMIC studies also discussed enforcement of drink and drug driving and enforcement of laws on the use of helmets, seat belts and child car safety seats.
Given the nature of the interventions or strategies, most were carried out at national or state-level, or within cities or towns.
Engineering
Out of the 51 papers in this category, more than three-quarters came from HICs, and discussed two approaches: road engineering and vehicle engineering. Most of the studies on road engineering from both HICs and LMICs described various road modifications including installation of roundabouts, changing road curvature, speed modification and other traffic calming measures. Both HIC and LMIC papers also described other interventions such as traffic and pedestrian countdown signals and exclusive lanes for bicycles, motorcycles and buses. Only HIC studies discussed audio tactile lane markings and street lighting. One LMIC study explored the use of pedestrian footbridges [59].
Vehicle engineering approaches were examined in mostly HIC studies. These included vehicle design, in-vehicle technologies such as seat belt reminders and air bags, as well as crash avoidance technologies such as anti-lock braking systems, alcohol ignition interlocks, intelligent speed adaptation, blind spot monitoring and lane departure warning systems. The three LMIC studies in this category discussed crash avoidance measures through anti-lock braking systems, break checks for bicycles, and motorcycle roadworthiness with installation of horns and other warning devices [56, 60, 61].
The settings for these interventions varied, although these were largely implemented in cities or towns, as well as at a national level.
Multi-component
Four studies discussed interventions or strategies with multiple components where three of the papers came from HICs. Each strategy had different combinations of the various approaches described above, with a unified focus on education and legislation or policies. The HIC strategies were carried out either in the community or in cities, whereas the LMIC strategy was implemented nationally.
Secondary prevention
Secondary preventative strategies and interventions were discussed in 60 papers. The individual approaches are categorised and summarised in Table 4.
The majority of the papers came from HICs and explored various forms of pre-hospital care, most of which were on pre-hospital airway management through intubation and ventilation. Other HIC papers looked at pre-hospital triage including one which described the use of a mobile stroke unit for imaging in neurotrauma, and pre-hospital fluid resuscitation [62, 63]. Another HIC paper was on the direct transport of victims to neurosurgical centres or operating theatres, bypassing nearby hospitals or health facilities [64].
Interventions reported in both LMICs and HICs included Emergency medical services (EMS). The HIC papers mostly described Air EMS where either a helicopter or aircraft was used in the transport of RTC or neurotrauma victims. The other HIC papers discussed a physician-led or physician-staffed EMS where a trained physician would attend the scene of trauma either together with or separate from other EMS staff. Most LMIC papers were on ground EMS or ambulance services.
Three papers, all from HICs, described different forms of crash notification and response systems that enable the occurrence of a crash or trauma to be reported or identified swiftly, and allow for EMS to arrive rapidly at the scene [65, 66, 67].
Organised trauma systems were explored in four papers, 2 from HICs, and 2 from LMICs. The LMIC systems focussed on life support (Basic Life Support by first responders and Advanced Life
[insert Table 4]
Support by paramedics), whereas the HIC systems included triage, transport, and a multidisciplinary pre-hospital management of patients [68, 69, 70, 71].
Out of the 7 papers on pre-hospital care training, the majority were from LMICs, where training was not only for healthcare staff, but also for lay responders, namely the police and public transport providers. There were also two papers describing the role of lay responders in providing first aid to RTC or neurotrauma victims, where the HIC paper discussed the role of police, and the LMIC paper, taxi drivers [73, 73].
Three papers were on multiple interventions, which described a combination of pre-hospital services, triage and resuscitation. All papers were from HICs.
The majority of the interventions or strategies were carried out at a State or Province-wide level. Some were implemented nationally, while others occurred in cities or towns.
Tertiary prevention
Forty papers dealt with various rehabilitative strategies and interventions for neurotrauma patients, and are summarised in Table 5. The description of these interventions can be found in Additional file 6.
More than 90 percent of the papers were from HICs where the majority discussed rehabilitation of cognitive function through various approaches including the use of video or computer games, virtual reality systems, music therapy, and electronic devices including mobile phones. Two studies investigated the role of mindfulness in improving cognitive functioning, where one also assessed physical and emotional functioning post-therapy [74, 75]. These we
re also examined in yet another study on mindfulness, which included yoga as a co-intervention [76]. All these papers were from HICs.
Similarly, other HIC studies discussed the role of various interventions or strategies in improving different aspects of functioning in neurotrauma patients. These ranged from art therapy, music therapy, rhythmic exercises with auditory cues and qigong. Two studies looked at
[insert Table 5]
multidisciplinary rehabilitation programmes which involved various healthcare workers with different expertise including physiotherapy and speech therapy [77, 78].
Strategies and interventions that addressed only emotional rehabilitation were described in three HIC studies, and included cognitive behavioural therapy, telephone counselling and a form of psychotherapy carried out by lay workers [79, 80, 81]. Physical rehabilitation was discussed in two HIC studies using exercise therapy and a home-based circuitry training [82, 83].
Occupational rehabilitation was explored in two papers, one using real-life activities as part of rehabilitation. Both papers were from HICs [84, 85].
Only three papers came from LMICs and described computerised cognitive rehabilitation, cognitive music therapy and occupational therapy [86, 87, 88].
Most of the interventions were carried out in rehabilitation centres, hospitals or medical centres. A few were carried out in schools, where the target population were children, and some in community centres or patient’s homes.
REVIEWS
Sixty-two reviews were included. The strategies and interventions together with the publication information have been categorised and can be found in Additional file 5. The description of the reviewed tertiary interventions is also found in Additional file 6.
Primary Prevention
This was explored in 41 reviews where most included primary papers from HICs, and assessed single interventions. The strategies and interventions that were most studied related to enforcement and legislation or policy. The three reviews that had primary papers only from LMICs evaluated multiple strategies and interventions.
Secondary Prevention
Only three reviews discussed secondary prevention. Two included HIC papers, which looked at pre-hospital tracheal intubation and direct transport to a neurotrauma centre, and one included LMIC papers, which assessed trauma systems [89, 90, 91].
Tertiary Prevention
Eighteen papers evaluated different rehabilitative interventions and strategies. The majority of reviews included primary papers from HICs or a combination of HICs and LMICs. Only one review, on the use of Acupuncture, included primary papers from China alone [92].
CONTEXTUAL FACTORS
This was discussed in 58 of the primary studies and four of the reviews, and varied depending on the studied intervention or strategy. These are summarised based on the interventions described, and are given below.
Primary prevention
Personal safety/protective equipment
Twenty-two papers looked into contextual issues relating to personal safety or protective equipment. Thirteen were on helmets, four on seatbelts, four on child safety seats and one on both helmets and seatbelts.
Use was influenced by attitude and knowledge of the protective effects as well as awareness of laws or campaigns promoting use. Relating to that, existence of laws or enforcement determined whether such equipment were used or otherwise, especially for short distance travel [93]. External pressure played a role, especially in children, where peers and family influenced if an individual would own or use such equipment. Likewise, promotional activities by healthcare professionals or the media also seemed to affect individual use. The history of an accident or head injury was found to increase use, where the danger of non-use had been real to the individual or their loved ones. All these were seen in both HIC and LMIC papers.
Cost and availability also affected whether safety equipment was utilised, especially in LMICs. In the HIC studies on helmets, the type and fit was also linked not only to use but whether the helmet was effective in protecting against head injury. In one LMIC study on child car seats, the make of the car was sometimes a barrier to use due to a poor fit [94].
Education/training/awareness raising
Contextual issues about education and awareness were discussed in nine studies. Four studies were on campaigns, all from HICs, where factors affecting implementation were linked to the methods used. Successful campaigns were those which were largely interactive, offered simple explanations and used multiple channels to deliver the message. Location of campaigns also played a role, where success was greater when it was carried out in areas with the highest risk.
Resource also affects success of educational ventures, where inexpensive methods are likely to be adopted by others and are more sustainable, and those requiring less manpower would have the capacity to cover a larger target population.
However, personal and environmental factors can result in lack of change in attitude or behaviour despite the acquisition of knowledge. For example in a study on a driving course for mature drivers, perceptions that it is just a ‘refresher’ or attending just to please family members resulted in lack of change in driving behaviour [95]. Similarly, a Graduated Driving programme designed to promote safe driving among teenagers could not ameliorate risky driving due to peer influence [96].
Local contexts are also important for the success of any educational programmes, where this should be in carried out in the language most familiar to participants, and take into account local conditions and programmes, as discussed in one LMIC paper [46].
Legislation and enforcement
Six studies discussed contextual issues concerning enforcement and legislation. In many LMICs, legislation with inconsistent and inadequate enforcement was found to be a barrier to success of the strategy or intervention. Also, manpower and resource management are important factors that allow for enforcement to be carried out efficiently and successfully, as described in both HIC and LMIC papers.
Two HIC studies examined traffic signs, where factors influencing their successful implementation were linked to design, visibility, knowledge and universal standardisation [97, 98].
Public knowledge of and attitude towards legislation and enforcement also play a role in the success of such strategies and interventions, for example, perceiving road laws as coercive, non-beneficial or for instilling fear can be a barrier to road safety, as explored in one LMIC study [99].
Engineering
Contextual factors pertaining to engineering strategies and interventions were explored in nine studies. Most studies discussed issues surrounding road engineering. Despite road engineering programmes, poor design resulted in the structure or facility being non-protective and inconveniencing road users, especially pedestrians. In an LMIC study on pedestrian foot bridges, good locations promoted use, although physical and psychological barriers resulted in non-use for some [59].
Another LMIC study on exclusive motorcycle lanes found this was highly accepted by motorcyclists as it facilitated riding and reduced commute time, in addition to promoting safety on the road [100].
A further three studies from HICs looked at vehicle engineering. One study from Spain showed that the better car designs encouraged speeding [101]. Additionally, vehicle technologies, while helpful and promote safety, could also lead to a false sense of security, especially among novice drivers. Conversely, not all cars could be fitted with such technologies, or even with seatbelts, due to their age and make, which is an issue commonly seen in LMICs.
Secondary prevention
Ground and Air EMS
In the five studies discussing contextual factors on ambulance services, issues such as cost, access and awareness of services affected the implementation of this strategy, especially in LMICs. Response time was also discussed where the presence of heavy traffic and lack of dedicated ambulance lanes resulted in delay in scene arrival. This resulted in a preference for private transport, which was considered more convenient.
Success of the ambulance service also relied on the resources available, not only in terms of numbers of vehicles for dispatch, but number of dedicated and trained staff who would be able to resuscitate and monitor patients, so the ambulance was not simply a transport medium. Again, this was described in the LMIC papers, where such resources were often lacking.
In the four HIC studies on air EMS, cost was also a factor that affected the success of this intervention. Unlike ground EMS, response time was swift for air EMS, as well as the ability to access remote areas. However, issues with street landing, especially when there is congestion, and space restriction within the helicopter made it difficult to carry out en-route resuscitation. Relating to that, the use of a larger aircraft, such as a Fokker 50, mitigated problems of space, noise and vibration.
Lay responders and pre-hospital care training
Three studies described contextual factors in relation to lay responders and pre-hospital training. Two LMIC studies looked at first aid training of taxi drivers, where attitudes influenced the implementation of this intervention. One study showed a positive attitude among drivers where they found the training increased their confidence, whereas in the other study, drivers felt that it was not necessary as their role is only for transport [73, 102]. Likewise in the HIC study on lay responders, police were trained in basic life support, but they also felt their role is policing and not to respond to medical emergencies [72].
Physician-staffed/physician-led EMS
The HIC study discussed the Rendezvous system, where an Emergency Doctor is also alerted and dispatched to the incident site, in addition to an ambulance with medical personnel [103]. In this system, the doctor is involved in pre-hospital care, but is able to work independently from the EMS and not have to go back-and-forth to the hospital, allowing them to respond quickly to emergencies and deal with more incidents.
Tertiary prevention
There were six studies exploring contextual issues for various different strategies and interventions, all from HICs.
Success of various approaches was very much dependent upon patient acceptability, where interventions that were engaging, easy to learn or use, and related to real-life activities were preferred. Involvement of different healthcare professionals and family members in rehabilitation also ensured patients received holistic care, and were better adjusted when returning home or to work. Success was also influenced by the timing of the intervention or strategy where outcomes were better with rehabilitation being carried out not long after the injury.