Edited by Rupert Kisser, Claudia Körmer, Mathilde Sector
Thank you to Francesca Racioppi, Delia Alexe and Eleni Petridou for
their substantial contribution
March 2005
Content
Members
of the Task Force
| Name |
Country |
| Kisser,
Rupert (Task Force leader) |
AT |
| Antoniades,
Costas |
CY |
| Benesova,
Veronika |
CZ |
| Benyi,
Maria |
HU |
| Detogni,
Claudio |
IT |
| Karski,
Jerzy |
PL |
| Nunes,
Baltazar |
PT |
| Pace-Asciak,
Renzo |
MT |
| Petridou,
Eleni |
GR |
| Rok-Simon,
Mateja |
SI |
| Racioppi,
Francesca |
WHO
Europe |
| Schelp,
Lothar |
SE |
| Sethi,
Dinesh |
WHO
Europe |
| Wagener,
Yolande |
LU |
Mission
of the task force
The DG SANCO of the European Commission initiated a task force on road
safety in the framework of the „Working Party on Accidents
and Injuries“ in December 2003. This task force shall give
recommendations to the European Commission/DG SANCO how the issue of
road safety from a public health point of view can be supported by DG
SANCO. A list of actions shall be provided to DG SANCO to provide
technical contributions to defining the contents of the Public Health
Programme 2005 to 2008, as well as other departments of the European
Commission, the National Competent Authorities, the European parliament
and the European council.
This report is considered as a summary of road safety
strategies. Its aim is to summarize recommendations for the EU public
health sector in order to address the issue of road safety within this
sector.
Why
is road safety an important issue for the Public Health sector?
Accidents and injuries in the field of road traffic are a major public
health problem in the world and also in Europe. Road traffic injuries
account for one quarter of the global burden of injuries
1.
The World
Health Organization (WHO) estimates road injuries will rank in sixth
place among the leading causes of death and burden of disease in 20201.
The WHO Global Burden of Disease 2002 database shows that about 10% of
people dying worldwide because of a road injury are dying in Europe
1.
Almost 40.000 persons were killed and about 1,725,500 injured in 2001
in the 15 EU Member States
2.
Traffic injuries are a leading cause of
death in the age group between 15 and 29 years of age
3
and the leading
causes of death among children 5-14 years old in Europe. Older
pedestrians account for nearly half of all pedestrian fatalities in
Europe
4.
Important health disparities exist between the New Member States and
the EU-15 in road traffic injuries. There is almost a 10-fold
greater risk of dying in a road accident in Lithuania and Latvia as
compared to Sweden
4.
Also an estimated 200,000 families per year were
----affected by the death or life-long disability of a family member
4.
The European Transport Safety Council estimates the costs of road
traffic injuries to society in the EU to be 180 billion Euros per
year
5.
The direct medical costs per patient due to a road injury are
about 600 Euro in the Euro region.
Key factors for road traffic injuries and their consequences for
society are
6:
- Speeding (about one
third of the fatal and serious accidents). Limiting
excessive speed would reduce the number of people killed annually in
the EU by 11 000 and of people injured by 180 0007)
- Driving under
influence of alcohol (about 10 000 deaths annually in the
EU8).
- Under-utilization of
seat belts and child restraints (10 000 car
occupants died in an accident because they did not wear their seat belt
over the year 19969)
- Poor road designs and
roadway environment
- Unsafe vehicle design
(car fronts)
- Under-implementation
of road safety standards
- Poor enforcement of
road safety regulations
The first three factors listed above are the main causes of deaths on
the roads in Europe.
Below is a summary of the evidence-based measures to reduce road
traffic injuries on a national and international level, from the WHO
World report on road traffic injury prevention:
- Engineering: The
improvements of road safety assessments, automotive
engineering through e.g. seat belts, airbags etc. to reduce the
consequences of accidents,
- Environment: Traffic
calming, road infrastructure changes (separating
pedestrians and cyclists from motorized traffic) as well as telematics
to construct traffic environments that prevent wrong behaviours of
drivers,
- Education: Traffic
education including skills training in the road
environment and improved driving licence training to teach road users
safe behaviour in road traffic (weak evidence exists of other
educational interventions to change human behaviour),
- Enforcement:
Legislation and enforcement to govern co-operations in
traffic without conflicts as well as safety standards.
- Evaluation: evaluation
of measures concerning their effectiveness to
prevent injuries has been systematically reviewed for some of these
measures.
Added
value by the involvement of the Public Health Sector
The work of the public health sector is framed within the public health
approach of data collection, research, prevention, evaluation, policy,
services and advocacy.
Road
traffic injury risks
In Western Europe there
is a decline in road traffic-related deaths
4.
Although all types of road users are at risk of having a traffic
accident, pedestrians and two-wheeler users are at greater risk of
dying than vehicle drivers and occupants
3.
Less information exists
about non-fatal injury risks as these data are not routinely collected.
Police data in most countries in Europe provide reliable and detailed
data about accidents involving a moving vehicle, but there is
considerable under reporting of non-collision accidents, especially
those involving pedestrians and cyclists
10
. From the public health
point of view there is no adequate reporting of all road-related
injuries.
The collection of more detailed data on identifying and monitoring risk
factors (e.g. excess speeds, drinking while driving) could be
integrated within existing public health databases. Furthermore,
systematic reviews are needed to determine the effectiveness of
existing interventions to reduce these risk factors.
Focus
on vulnerable road users
Vulnerable road users are defined by the Organisation for Economic
Co-operation and Development as “those unprotected by an
outside shield, namely pedestrians and two-wheelers”
11.
This
task force would also highlight within this definition those groups
that have added risks: children, elders, and persons with a disability.
Children can not estimate speed and risks and are often too small to
see cars and their drivers early enough. Thus they are at an especially
high risk in road traffic, and are unable to cope with difficult
traffic environments till about 10 years of age. That is why they are
considered to be the most vulnerable road users
4.
Also, elderly people are considered to be vulnerable road users as they
have a gradual decreased ability to cope with complex traffic
situations, and are physically more fragile with age, thus suffering
more severe consequences in the event of an injury. That is why they
account for nearly half of all pedestrian fatalities in European OECD
countries.
Persons with disabilities refers to individuals with a physical,
sensory or mental impairment that are limited in full participation due
to environmental barriers in society, specifically for the purposes of
this report, within the road traffic environment. The Commission has
recognized that it is a basic right of persons with disabilities to
live in a barrier-free environment, and have the same protection as
that of others
12.
Thus, although cyclist, pedestrians, playing children, elderly, persons
with disabilities (blind, deaf, persons with wheelchairs) have a
greater risk of mortality than other road users, policy areas in the
prevention of road traffic injuries engage mainly in the improvement of
road traffic from the perspective of motorised road traffic users
4.
The
recent the project “Promotion of measures for vulnerable road
users –PROMISING” funded by DG transport recommends
mainly road structure improvements and enhanced vehicle design to
protect vulnerable road users
13.
Vulnerable road users have less
influential lobbies and cause little risk to other road users,
therefore they are often unheard. Also, the huge burden of falls on
public roads and other injuries have hardly been recognized. Vulnerable
road users must therefore be a special focus for the public health
sector of the European Commission
14.
Data
on external causes
Databases such as CARE
(Community database on Accidents on the Roads in
Europe) and IRTAD (International Road Traffic and Accident Database)
collect data on road traffic deaths and injuries, based on detailed
data on individual accidents as collected by Member States. Much of the
data reported from Member States to IRTAD or CARE are registered by the
police. It is known that the number of collisions without counterpart
e.g. injuries of children and seniors as pedestrians and bicyclists,
are much higher than those reported to the police10. It exceeds even
the number of people injured by motor vehicle crashes.
Another source of data is the European Injury Database (IDB) which
contains some data on injuries on public roads without counterpart, and
will register systematic information on causes, course of events and
consequences of traffic accidents in the near future.
Thus, up to now no systematic data exists on post-injury care or
resulting disability due to road traffic injuries to vulnerable road
users. Because these consequences of road traffic are not reported in
routine statistics and are therefore hardly addressed by road traffic
related policy decisions. The United Nations is supporting research on
capturing disability data systematically around the
world—hopefully this will be a source of data in the future.
Data on these topics must be promoted within the injury prevention
research community. The major existing data sources need to be analysed
in order to produce a detailed report on the burden of road traffic
injuries sustained by vulnerable road users, including trends. It is
imperative that the road traffic injury data systems be improved upon
and that each Member State makes an effort to provide high quality data
at the national level.
Public
health policy
Generally, the reduction of road traffic injuries, including injuries
in non-motorized transport, should be included in programmes of the
national and international public health sector. These efforts should
be connected to campaigns conducted by the transport and other
responsible sectors. The public health sector should support these
efforts with evidence-based arguments, and should pay special attention
to the safety needs of vulnerable road users. Duplication of work has
to be avoided, but additional value should be created.
Recommendations
for DG SANCO
An effective road safety strategy for the protection of vulnerable road
users is multi-faceted, based on the following components: advocacy,
injury surveillance; the use of injury indicators; and policy actions
(see Figure 1 on page 19 for a visual representation of the role DG
SANCO may have in road safety).
Listed below are public health recommendations for DG SANCO on the
issue of road safety in Europe:
A.
Intersectoral collaboration with DG TREN
- Convene a technical
meeting of
experts, from the health
sector and
transport sector, who would be invited to take stock from the
background provided by the task force report and advise on next steps,
taking into account the need to provide value added to activities which
are already taking place in the Region. An effort should be made to
frame the activities within international commitments: the World Health
Assembly Resolution on Road Safety and Health (WHA57.10 May 2004), the
Children’s Environment and Health Action Plan for Europe
(EUR/04/5046267/7 25 June 2004) and Declaration (EUR/04/5046267/6 25
June 2004) and European commitments: Directorate General for
Transport-research and European Road Safety Action Programme (Halving
the number of road accident victims in the European Union by 2010: A
shared responsibility, COM(2003) 311 final), and the European Traffic
Safety Council. Collaboration with DG Environment is also needed.
- Promotion of traffic
calming measures by the
health and transport
sector together for changes in road infrastructure and urban
planning (e.g. separating pedestrians and cyclists from motorized
traffic) as well as 30km/h zones, elder driver safety assessments and
re-orientation of the transport demand towards safer transport modes4.
- Promotion of alternative
modes of transportation by
the health and
transport sector by showing that public transport, cycling and walking
have positive effects to the health and should be promoted from a
public health point of view. In many environments (inner cities e.g.)
these forms of transportation provides additional physical exercise,
reduce air pollution, and reduces the risk of fatal car crashes.
Motorised road traffic carries people from the place of departure to
their destination individually, but account at the same time for
polluting the air, noise – in addition to the high numbers of
injuries. The WHO report about road safety in Europe notes the harmful
effect of physical inactivity to societies` health caused by using
motorised vehicles4. It is necessary to look at advantages and losses
for public health and reflect traffic modes accordingly4. Environmental
conditions to support the safe usage of alternative modes of transport
have to be focused on.
- Ensure that vulnerable
road users are adequately addressed in the
implementation of a European Action
Plan on
Road Safety from a public
health point of view, and harmonisation of this plan with existing DG
TREN strategies. This plan should set measurable five year targets,
should summarize actions in order to meet these goals and should
identify responsible institutions. Accompanying partnership with
experts of DG TREN should be established.
B.
EU Health Information system
The following
improvements would be necessary within the EU Health
Information System:
Injury
Surveillance System
- External causes of road
injuries: ICECI Coding for
non-fatal road
injuries is not yet documented by most of the EU-Member States. Through
an enlargement of the IDB to road traffic injuries according to ICECI,
additional information on course of events etc. will soon be made
available for road traffic injuries on a European level. This is needed
to have a more comprehensive view on injury causes and consequences.
This information should be included in European reports.
- Comprehensive view on road
injuries: To minimize the
underreporting of
road injuries a compilation of the injury data in CARE (Community Road
Accident Database)15,
IDB and Hospital Discharge Register must be
combined to give a comprehensive view on injuries of all road users,
including all injuries without counterpart, deaths, disabilities and
hospital patients.
- Harmonised data
collection: In order to
enhance harmonisation of road
injury data collection between transport and public health sectors,
regular exchange of information between CARE and IDB administration is
recommended, to link hospital data with police-based data. This will be
done with the input from the Member States.
- Easy central data access:
This compilation of data should be easily
accessible and be actively promoted at e.g. the health portal of the DG
SANCO. This will be done with the input from the Member States.
Injury
indicators
A systematic overview
about the scope of injuries, especially
disabilities and costs for Europe serves as a basis for comparing
developments of injury incidences over time, injury changes by Member
State and international comparisons according to national policies.
- Public health oriented
road injury indicators: Road
injury indicators
for the revised road injury definition (including also non-motorized
mobility and public transport) should be included in the list of
European Community Health Indicators (ECHI) of DG SANCO.
- Revised road traffic
indicators: By using
additional IDB data on road
traffic injuries underreporting by the police could be amended in order
to obtain a more realistic indicator for road injuries.
- Disability indicators:
As the disability rate due to road traffic
injuries is especially high compared with other injuries road injury
disability indicators should be developed on the basis of routine
health data for regular reporting and benchmarking (similar to the AIS
- Abbreviated Injury Severity Scale based on ICD diagnosis). (In
addition to the indicators already used in epidemiology such as: DALYs
- Disability adjusted Life Years, YLD - Years Lost due to Disability)16.
- Injury risk indicators:
In order to obtain injury risk indicators based
on exposure data on frequency of transport modes (private and public
transport) and overall mobility should be included in the ECHI list of
indicators as well.
- Quality of life:
Quality of life measures (e.g. perception of health,
satisfaction with life etc.) of persons having suffered a road traffic
crash are important to use because they capture various domains of a
persons functioning, physical domain, psychosocial, adaptive etc.
Studies in this field show that significant psychological distress
following road traffic crashes is common4. Respective qualitative data
using health related quality of life tools should be collected
regularly by each EU Member State.
- The cost effectiveness of
prevention measures should be
taken into
account as already stated in the report “Costs-Benefit
Analysis of Road Safety Improvements”17.
In the SWOV report
“Economic evaluation of road safety measures” two
evaluation methods called “monetary methods” are
described: the cost benefit analysis (CBA) and the cost-effectiveness
analysis (CEA). Direct and indirect effects of measures such as
increased safety feeling of people or air pollution as well as running
and maintenance costs have to be also considered in the evaluation of
road safety measures18.
The report “Costs-Benefit Analysis of
Road Safety Improvements” is analysing measures such as
speeding, drunk driving and non-use of seat belts by value of lives
saved, injuries avoided, property damage costs etc. Implementation of
the proposed measures would not only safe lives, but also add to the
productivity of society17.
Models for comprehensive cost-effective
decision making for road traffic-related injuries are also needed.
- Research and innovation:
Support research and innovation for best
practise strategies to reduce morbidity and mortality due to road
traffic.
C.
DG SANCO Policy Making
Actions by DG SANCO should concentrate on activities which are not the
responsibility of other European institutions, which cannot be taken on
national level, and which provide an additional European value.
Generally, such actions are: facilitation of actions on national level
(e.g. by information clearing on good practices available,
dissemination of this information, support of network building,
standardisation of programmes, providing specific tools for
administrations and other stakeholder, additional European campaigns on
certain issues to highlight their relevance). In particular, the
following European public health actions on road safety should be
considered:
- Identification of stake
holders: The key stake
holder groups and their
focal points in Europe should be identified, also their specific
opportunities and responsibilities, as well as their information needs
regarding road safety for vulnerable road users. This would facilitate
actions of concerned governmental sectors (health administration,
social security sector, communities etc.) but also of influential
non-governmental interest groups (child protection groups, senior
citizens organisations, bicyclists interest groups, health promotion
agencies, and particularly victims organisations etc.).
- Advocacy Tools:
Development and distribution of advocacy documents in
order to provide convincing arguments for the inclusion of traffic
safety issues for vulnerable road users in public health policy and
programmes, as well as for transport and other sectors, in order to
intensify the inclusion of vulnerable road users in road safety
programmes. These documents should provide public health arguments,
which are not yet well established, e.g. epidemiological aspects and
health indicators.
- Inventories of good
practice: review existing
systematic reviews of the
effectiveness of different intervention strategies (behavioural,
environmental, etc.) and identify interventions which have not yet been
reviewed and assess their effectiveness, including case
studies. These findings would serve as the content of a policy-oriented
manual that is current and evidence-based. This tool shall be developed
within the Work package 5 “Initiatives for interventions of
the Public Health Sector to prevent accidents among vulnerable road
users” part of the “APOLLO: Strategies and Best
Practices for the Reduction of Injuries” project submitted to
the EC according to the Public Health Work Plan 2004. The aim is to
assist the European Commission in guiding Member Sates to implement
evidence-based strategies.
- Usage of formal
distribution channels: Formal
dissemination of advocacy
tools and information to the member state administrations and European
Parliament about the European public health actions on traffic safety
and the policy recommendations, via conferences, expert meetings, web
board, newsletters, etc.
- Promote national road
safety plans: The transport
and public health
sector should work together to promote national policy actions. But
also actions by other relevant sectors (law enforcement, education,
welfare, economy) should be aligned in order to achieve reductions of
road injury risk. The WHO recommends in their European road safety
report to identify a lead agency in government to guide and prepare a
national road safety strategy and plan for action, allocate resources,
implement specific actions and support the development of national
capacity and international co-operation4.
D.
Prevention Actions
- Focus on Vulnerable Road
Users: a European
multi-faced intervention to
target pedestrians and bicyclists in the road environment is needed,
with a special focus on children and elders. The key message is for all
of those in and around the roads to keep children and elders mobile,
but safe.
- Capacity building:
The public health sector should implement basic
knowledge on injury prevention in general and traffic safety in
particular in its professional training, of medical doctors, nurses,
public health advisors etc. The content of basic knowledge should be
defined at the European level. An interdisciplinary approach is needed
for this, with collaboration with other working parties of the
Commission.
- Inclusion in health
promotion: Mainstream road
safety objectives should
be integrated into the public health agenda, also in the member states.
Road injury prevention – like injury prevention in general
– should be included in health promotion programmes. For the
time being, there are numerous activities all over Europe on health
promotion but – in spite of the fact that injuries are a
major health problem – injuries are usually excluded. The
inclusion of injury prevention on a national level can be done by
national health administrations, which frequently set guidelines (or
legislation) for financing health promoting activities, in order to
change attitudes and behaviours regarding risky road behaviours and at
the same time promoting road safety.
- Delivery of health care:
Relevant public health services are key
stakeholders in prevention and treatment of road traffic injuries. A
review is needed of the role of pre-hospital care and practices in
order to identify good practices in this area, specifically time to
hospital and quality of care at the crash site. Additionally, medical
and psychological assessments on a person’s ability to drive
should be performed to a greater extent, especially for the safety of
older persons. The health sector plays an integral part in
disseminating health information to patients. Hospitals are a unique
location for health promotion. Discussion with the health sector is
needed to establish guidelines on how health structures can promote
road safety for their employees and clients.
- Evaluation of programmes: For
a continuing improvement of the road
traffic situation the implemented measures should be evaluated
regarding effectiveness and sustainability using available health
indicators. The health sector can take a leading role in the
formulation of health objectives and controlling of changes by using
health indicators. This gives a strong voice to the health sector.
Appendix
Figure 1. Role of DG SANCO in Road Safety
Key
documents of the European Commission/DG Transport
- White book, European
Transport policy for 2010, Time to decide,
European Commission, Luxembourg 2001
- Saving 20.000 lives on
our roads, A shared responsibility, European
Road Safety Action Programme, European Commission, Belgium 2003
- Road Safety, Results
from the transport research programme, European
Commission, Belgium 2001
- Costs-Benefit Analysis
of Road Safety Improvements . Final Report, 12
June 2003 by the ICF Consulting and the Imperial College Centre for
Transport Studies, UK.
- SARTRE -
Social Attitudes to Road Traffic Risks in Europe
project. Survey results that focus on the attitudes of European
citizens to the three main causes of road fatalities: speed limits,
wearing seat belts, and alcohol use.
- Information gathering
on speeding, drink driving and seat belt use in
the member states. Final Report, Part I and II, May 2003 by Clifford
Chance.
Further
key documents/commitments in this field
- DG SANCO established
the Strategy Paper “Actions for a safer
Europe” (2004)
- The UN General
Assembly established the Global Road Safety Crisis
Report
- WHO-Geneva summarised
traffic injury events and their prevention
measures within the „World Report on road traffic injury
prevention (2004)“
- WHO-Europe focused
within the report „Preventing road traffic
injury: a public health perspective for Europe“ on road
traffic injuries in the European region (2004)
- OECD established a
report and policy brief “Keeping children
safe in traffic” recommending countries to implement a series
of measures to address this issue (2004) http://www.oecd.org/dataoecd/27/25/31859113.pdf
- OECD report
“Safety of vulnerable road users”
presents a review of the current safety situation of vulnerable road
users in OECD Member countries (2001)
- Resolution on road
safety and health of the World Health Assembly to
address the lack of safety on the world's roads (2004)
References
Actions for a safer Europe, Strategy Paper established by DG SANCO,
Luxembourg 2004
Costs-Benefit Analysis of Road Safety Improvements, Final Report, ICF
Consulting, Ltd. & Imperial College Centre for Transport
Studies. London, June 2003
Economic evaluation of road safety measures, SWOV Institute for Road
Safety Research, Paul Wesemann, Leidschendam, 2000
IPP Report: A surveillance based assessment of medical costs of injury
in Europe: Phase 2, Final Report, co-ordinated by Consumer Safety
Institute for DG SANCO, Amsterdam, 2004
IPP Report: Comprehensive View on European (HLA) Injury Data,
co-ordinated by Institute “Sicher Leben” for DG
SANCO, Vienna 2003
The injury chart book, a graphical overview of the global burden of
injuries, Department of Injuries and Violence prevention, WHO Geneva,
2002
Transport Safety Performance in the EU: A Statistical Overview,
European Transport Safety Council, Brussels, 2003
Preventing road traffic injury: a public health perspective for Europe,
WHO/Europe, Copenhagen 2004
Priorities for child safety, agenda for action, European Child Safety
Alliance, ECOSA, Amsterdam, 2004
PROMISING, Promotion of Measures for Vulnerable Road Users, SWOV,
funded by EC/DG Transport, Netherlands 2001
Road Traffic Injuries, Fact sheet, WHO, Geneva
Unfallstatistik 2003, Kuratorium für Verkehrssicherheit, Heft
36, Wien, März 2004
Weissbuch, Die europäische Verkehrspolitik bis 2010,
Weichenstellungen für die Zukunft, Luxembourg 2001
World report on road traffic injury prevention, WHO, Geneva 2004
EC Care database:
http://europa.eu.int/comm/transport/care/
WHO, Burden of Injuries project:
http://www3.who.int/whosis/menu.cfm?path=evidence,burden,burden_estimates&language=english
Footnotes
3
World
report on road traffic injury prevention, WHO, Geneva 2004.
4
Preventing
road traffic injury: a public health perspective for Europe,
WHO/Europe, Copenhagen 2004.
5
Transport
Safety Performance in the EU: A Statistical Overview, European
Transport Safety Council, Brussels, 2003, page 7
6
Road
Traffic Injuries, Fact sheet, WHO, Geneva, 2004.
7
ETSC
report ‘Reducing traffic injuries resulting from excess and
inappropriate speed’, Jan.1995, saying that an average speed
reduction of 5 km/h should result in a reduction of over 11.000 fatal
casualties annually in the EU (based on IRTAD, 1994).
8
Commission
Recommendation of
17.01.2001
(OJ C 48/2), paragraph 1.2.2.
9
ETSC
report on police enforcement,
May 1999.
10
Hvoslef
H.
Under-Reporting of road traffic accidents recorded by the police, at
the international level. Operational Committee
of IRTAD and
Norwegian Public Roads Administration, Oslo. Norway, 1994.
11
Scientific Expert Group on the Safety of Vulnerable Road Users
(RS7-98). Safety of Vulnerable Road Users, OECD, 1998.
12
Equal Opportunities For People With Disabilities: A European Action
Plan, Com(2003) 650 Final, Brussels, 30.10.2003.
13
PROMISING, Promotion of Measures for Vulnerable Road Users, SWOV,
funded by EC/DG Transport, Netherlands 2001
14
Actions
for a safer Europe, Strategy
Paper established by DG SANCO, Luxembourg 2004.
15
The database CARE was built to quantify road safety problems and
provides compared to other road injury databases a high level of
disaggregation:
http://europa.eu.int/comm/transport/care/
16
http://www3.who.int/whosis/menu.cfm?path=evidence,burden,burden_estimates&language=english
17
Costs-Benefit Analysis of Road Safety Improvements, Final Report, ICF
Consulting, Ltd. & Imperial College Centre for Transport
Studies. London, June 2003
18
Economic evaluation of road safety measures, SWOV Institute for Road
Safety Research, Paul Wesemann, Leidschendam, 2000, page 17ff