1. Traffic injuries to children and young people in Hertfordshire
Public Health Evidence and Intelligence,
Transport Planning Data Team
March 2015

2. Content Background 2 Data sources and definitions 3 Data caveats 4
Key messages
Comparison to England 7
Severity, road user type, sex, age, district and deprivation
Speed limits and time of day 26 1

3. Background
In June 2014 Public Health England (PHE) produced a report “Reducing unintentional injuries on the roads among children and young people under 25 years”. Further details along with national and upper tier local authority level data are available from:
Generally, Hertfordshire has lower rates of traffic injuries involving under 25s than England. However, in 2013 one in every 1,745 young people aged between 15 and 24 suffered a serious or fatal traffic injury in Hertfordshire.
Aim and purpose
This report is a collaboration between the Public Health Evidence and Intelligence team and Data Transport Planning, Highways using local police and hospital data to look in more detail at the picture for Hertfordshire and its districts. It was written by Claire Tiffany (Senior Public Health Analyst).
For further information, please contact 2

4. Data sources and definitions
Analysis based on local STATS 19 and SUS data held by Hertfordshire County Council.
STATS 19: Police reported road accidents, Hertfordshire only, 0-24 years.
SECONDARY USES SERVICES (SUS): Local hospital data, emergency hospital admissions only, 0-24 years, ICD10 codes V01-V89 (non-traffic injuries filtered out). Includes patients registered with NHS East and North Hertfordshire CCG and NHS Herts Valleys CCG, excludes patients registered with three GP practices in Royston. Deprivation analysis based on patients resident in either CCG.
CONFIDENCE INTERVALS: All confidence intervals in charts are 95%.
DEFINITIONS used in STATS 19: Police-reported traffic casualties are categorised in three severities. Fatal casualties sustain injuries which cause death less than 30 days after the collision. Injuries are categorised as severe when a casualty is detained in hospital as an “in-patient”, or any of the following injuries whether or not they are detained in hospital: fractures, concussion, internal injuries, crushings, burns (excluding friction burns), severe cuts, severe general shock requiring medical treatment and injuries causing death 30 or more days after the accident. Slight injuries are of a minor character such as a sprain (including neck whiplash injury), bruise or cut which are not judged to be severe, or slight shock requiring roadside attention. 3

5. Data caveats
There may be variation between hospital trusts in the way hospital admissions are coded. Often the focus is on the type of injury (e.g. fracture) and its treatment rather than the underlying cause which can create variations in whether the episode is recorded as a traffic accident. There may be differences in admission thresholds. There may be variation in data recording completeness. Young people who attend A&E but are not admitted to hospital are not included.
Not all road casualties are reported to police.
Rates are expressed as injuries/ deaths on the roads, under 25 year olds, per 100,000 residents (crude rate). Therefore, areas with low resident populations but which have high inflows of people or traffic may have artificially high rates because the at-risk resident population is not an accurate measure of exposure to transport. This is likely to affect the results for employment centres/ commuter areas and sparsely populated rural areas which have high numbers of visitors or through traffic. 4

6. Key messages (1)
Generally, Hertfordshire has lower rates of traffic injuries involving under 25s than England. However, on average, nine road users aged under 25 were killed each year in Hertfordshire, 1,094 had an injury recorded by the police of which 122 were serious.
The average yearly number of under 25 hospital admissions resulting from road traffic injuries (176) was 34% higher than the number of killed or serious injuries recorded by the police.
Young males were more likely to be involved in a traffic injury than young females, particularly the more serious the injury.
Overall, rates of under 25s killed or seriously injured (KSI) on the road or admitted to hospital as a result of a road traffic injury were higher in the older age groups (15 to 24 years old).
Rates of under 25 year old car occupants involved in traffic injuries were higher for 18 to 22 year olds, whilst for pedestrians and cyclists they were higher in 10 to 14 year olds.
The majority of under 25 year old road casualties in Hertfordshire involved car occupants. This follows the national trend, although the proportion is slightly higher in Hertfordshire than England. 5

7. Key messages (2)
Vulnerable road users such as cyclists and pedestrians make up a greater proportion of emergency hospital admissions than casualties recorded by the police.
Hertsmere had the highest rate of under 25 year old road casualties recorded by the police, whilst St Albans had the highest number. Differences between districts are influenced by many factors such as whether it is predominantly rural or urban, types and lengths of roads, levels of traffic, travel behaviour, deprivation and population density.
Rates of under 25 year old road casualties and KSIs are lowest in the least deprived areas. There is no clear gradient in the more deprived areas.
The majority of under 25 year old pedestrian KSIs occur in rush hour before and after school.
Overall, the majority of KSIs occur in 30mph zones, although those involving car occupants are more likely to occur in 60 or 70 mph zones.
With the exception of 2012 the overall rate for KSIs in under 25s has fallen steadily over the last five years. 6

8. Comparison to England 7

9. Summary of Hertfordshire under 25 year old traffic injuries compared to England
Indicators lower (better) than England
Emergency admission rates* - all road user types
Killed or Seriously Injured (KSI) rates* - all age groups
Motorcyclist KSI rates - age and 20-24
Car occupant KSI rates - age and 20-24
Indicators higher (worse) than England
Pedestrian KSI rates age (10.2 per 100,000 population compared to 9.8)
Pedal cyclist KSI rates age (8.4 per 100,000 population compared to 6.5)
Speed limit
Lower percentage of KSIs in 30 mph zones in Hertfordshire compared to England - all road user types
* Emergency admissions from 2008/09 to 2012/13, KSIs from 2008 to 2012
Source: Reducing unintentional injuries on the roads among children and young people under 25 years, Hertfordshire, Public Health England: 8

10. Traffic injuries by severity, road user type, sex, age, district and deprivation9

11. Road casualties and emergency hospital admissions, 0-24 years, Hertfordshire* by sex, average number per year, (STATS19) and 2011/12 to 2013/14 (SUS)
On average 1,225 road users per year under 25 years old had an injury recorded by the police of which 10% (122) were serious and 1% (9) were fatal, similar to nationally
On average there were 176 emergency hospital admissions to under 25s as a result of a road traffic injury each year
- Young males were more likely be involved in a traffic injury, particularly the more serious injuries
Data Source
Severity
Males (per year)
Females (per year)
Total (per year)
Male to female ratio
STATS19
Killed 7 2 9
3.2 to 1
Seriously injured 88 34
122
2.6 to 1
Slightly injured
607
487
1,094
1.2 to 1
SUS
All admissions
104 72
176
1.4 to 1
Source: Hertfordshire County Council
SUS data based on GP registered population (excludes 3 practices in Royston) 10

12. Killed or seriously injured (KSI) All severities (per year)
Road casualties, 0 to 24 yrs, Hertfordshire, by road user type, average per year
Road User Type
Fatal
(per year)
Killed or seriously injured (KSI)
All severities (per year)
% of all severities
Car occupants 6 53
812
66.3%
Pedestrians 2 30
154
12.5%
Motorcycle riders 1
128
10.5%
Pedal cyclists 15 91
7.4%
Minibus/ bus/ coach 7
0.6%
Taxi
Other users 26
2.1%
Total 9
131
1,225
100.0%
The highest proportion of road casualties (66%) involved car occupants, higher than England (59% in )
The majority of fatalities (67%) were car occupants, higher than England (58% in )
Pedal cyclists made up 7% of road casualties and 11% of KSIs (this compares to 9% and 11% for England in )
Source: STATS 19, Hertfordshire County Council 11

13. % of all traffic injuries age 0-24 years
Emergency hospital admissions, 0 to 24 yrs, Hertfordshire*, by road user type, by sex, average per year 2011/12 to 2013/14
The highest proportion of emergency hospital admissions as a result of traffic injuries involved car occupants (32.5%)
Pedal cyclists made up 19% of emergency hospital admissions (this compares to 11% of KSIs)
Overall, hospital admissions were made up of 1.5 times more males than females, with 15 times more male than female motorcycle riders and 4.5 times more male than female pedestrians
Road User Type
Male (per year)
Female (per year)
Total (per year)
Male to female ratio
% of all traffic injuries age 0-24 years
Car occupants 29 57
1.0 to 1
32.5%
Pedal cyclists 20 14 34
1.5 to 1
19.3%
Pedestrians 27 6 33
4.5 to 1
18.7%
Motorcycle riders 25 2 26
14.8 to 1
14.9%
Other users 3 22
0.1 to 1
14.6%
Total
104 72
176
1.4 to 1
100.0%
Source: SUS, Hertfordshire County Council 12

14. Killed or seriously injured, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by age band 2009 to 2013
With the exception of 2012 the overall rate of under 25s killed or seriously injured (KSI) has fallen steadily over the last five years from 45 per 100,000 population in 2009 to 29 per 100,000 in 2013
There were 656 under 25 KSIs in the five year period – an average of 131 per year
Rates were considerably higher for 15 to 24 year olds with the majority of KSIs (77%) in this age group
Note: Rates based on numbers less than 5 are excluded
Source: STATS19, Hertfordshire County Council; ONS MYE 13

15. Emergency hospital admissions, rate per 100,000 population, 0 to 24 yrs, Hertfordshire*, by age band 2011/12 to 2013/14
Rates of emergency hospital admissions resulting from road traffic injuries decreased slightly in 2013/14 to 44 per 100,000 population
There were 529 under 25 year old emergency admissions for road traffic injuries in the three year period – an average of 176 per year
Rates are highest for 15 to 24 year olds with the majority of admissions (63%) in this age group
Note: Rates based on numbers less than 5 are excluded
Source: SUS, Hertfordshire County Council; GP population, NHS area team
* GP registered population (excludes 3 practices in Royston) 14

16. Road casualties, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by district 2009 to 2013
Hertfordshire had an under 25 road casualty rate of 357 per 100,000 population, equivalent to 1,224 casualties per year
Hertsmere had the highest rate (457 per 100,000 equivalent to 141 casualties per year) followed by St Albans (393 per 100,000 equivalent to 167 casualties)
The lowest rates were in East Hertfordshire (295 per 100,000 equivalent to 120 casualties per year) and Dacorum (317 per 100,000 equivalent to 138 casualties)
Source: STATS19, Hertfordshire County Council; ONS MYE 15

17. Killed or seriously injured, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by district 2009 to 2013
Hertfordshire had an under 25 killed or seriously injured (KSI) rate of 38 per 100,000, equivalent to 131 KSIs per year
Rates of under 25 KSIs did not differ significantly across the districts ranging from 30 per 100,000 population in Watford to 44 per 100,000 in North Hertfordshire
Source: STATS19, Hertfordshire County Council; ONS MYE 16

18. Road casualties, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by deprivation quintile 2009 to 2013
The least deprived quintile had the lowest rate of under 25 road casualties at 197 per 100,000 population (equivalent to 123 casualties per year)
The third most deprived quintile had the highest rate at 449 per 100,000 population (equivalent to 313 casualties per year)
Source: STATS19, Hertfordshire County Council; IMD 2010; ONS MYE 17

19. Killed or seriously injured, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by deprivation quintile 2009 to 2013
Under 25 Killed or Seriously Injured (KSI) rates followed a similar pattern to road casualties with the least deprived quintile experiencing the lowest rate (22 per 100,000 population equivalent to 14 KSIs per year) and the third most deprived experiencing the highest rate (53 per 100,000 population equivalent to 37 KSIs per year)
Source: STATS19, Hertfordshire County Council; IMD 2010; ONS MYE 18

20. Emergency hospital admissions, rate per 100,000 population, 0 to 24 yrs, Hertfordshire*, by deprivation quintile 2013/14
Details of where patients live (area of residence) are only available from local hospital data from 2013/14 onwards
Numbers are not large enough to distinguish differences by deprivation quintile and become even smaller at district level
Source: SUS, Hertfordshire County Council; IMD 2010; GP population, NHS area team
* Resident GP registered population (excludes 3 practices in Royston) 19

21. Car occupant KSI, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by age 2009 to 2013
There were 266 under 25 year old car occupants killed or seriously injured (KSI) in the 5 year period – an average of 53 per year
18 to 20 year olds had the highest rates, peaking at 19 (67 per 100,000 equivalent to 8 KSIs per year)
31 KSIs (12%) involved under 16 year olds (numbers are too low to report by single year of age)
Source: STATS19, Hertfordshire County Council; ONS MYE 20

22. Car occupant emergency hospital admissions, rate per 100,000 population, 0 to 24 yrs, Hertfordshire*, by age 2011/12 to 2013/14
There were 172 traffic injuries involving car occupants aged under 25 in the 3 year period – an average of 57 per year
18 to 22 year olds had the highest rates, peaking at 21 (70 per 100,000 equivalent to 9 admissions per year)
26 (15%) were aged under 16 (numbers are too low to report by single year of age)
Source: SUS, Hertfordshire County Council; GP population, NHS area team
* GP registered population (excludes 3 practices in Royston) 21

23. Pedestrian KSI, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by age 2009 to 2013
There were 149 under 25 year old pedestrians killed or seriously injured (KSI) in the 5 year period - an average of 30 per year
10 to 14 year olds had the highest rate (14 per 100,000 population equivalent to 9 KSIs per year)
Source: STATS19, Hertfordshire County Council; ONS MYE 22

24. Pedestrian emergency hospital admissions, rate per 100,000 population, 0 to 24 yrs, Hertfordshire*, by age 2011/12 to 2013/14
There were 102 emergency hospital admissions involving pedestrians under 25 in the 3 year period – an average of 34 per year
10 to 14 year olds had the highest rate (14 per 100,000 population equivalent to 10 admissions per year)
Source: SUS, Hertfordshire County Council; GP population, NHS area team
* GP registered population (excludes 3 practices in Royston) 23

25. Cyclist KSI, rate per 100,000 population, 0 to 24 yrs, Hertfordshire, by age 2009 to 2013
There were 76 under 25 year old cyclists killed or seriously injured (KSI) in the 5 year period - an average of 15 per year
10 to 14 year olds had the highest rate (10 per 100,000 population equivalent to 7 KSIs per year)
Less than 5 KSIs involved under 10 year olds
Source: STATS19, Hertfordshire County Council; ONS MYE 24

26. Cyclist emergency hospital admissions, rate per 100,000 population, 0 to 24 yrs, Hertfordshire*, by age 2011/12 to 2013/14
There were 99 emergency hospital admissions involving cyclists under 25 in the 3 year period – an average of 33 per year
10 to 14 year olds had the highest rate (21 per 100,000 population equivalent to 15 admissions per year)
10 admissions (10%) were to under 10 year olds
Source: SUS, Hertfordshire County Council; GP population, NHS area team
* GP registered population (excludes 3 practices in Royston) 25

27. Speed limits and time of day26

28. Pedestrian KSI, 0 to 16 yrs, Hertfordshire, by hour of the day 2009 to 2013
There were 98 pedestrian KSIs over 5 yrs
The majority (73%) occurred during rush hour (8-9am and 3-7pm)
The evening peak is extended for several hours after school reflecting the range of activities children are involved.
Note: Numbers less than 5 are excluded
Source: STATS19, Hertfordshire County Council 27

29. KSIs, 0 to 24 yrs, Hertfordshire, by road user type and speed limit of the road 2009 to 2013
The majority (52%) of the 639 under 25 year olds killed or seriously injured (KSI) over the 5 years occurred in 30 mph zones - this holds true for pedestrians (83%), cyclists (74%), motorcyclists (57%), but not for car occupants (26%)
The majority (57%) of KSIs involving car occupants occurred in 60 mph (27%) or 70 mph (30%) zones
Less than 5 KSIs were in 20mph zones
Note: Numbers less than 5 are excluded (includes all road user types for 20 mph speed limit)
Source: STATS19, Hertfordshire County Council 28