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Cohort Profile
Cohort profile: Early pandemic evaluation and
enhanced surveillance of COVID-19 (EAVE II)
database
Rachel H. Mulholland ,
1
Eleftheria Vasileiou,
1
* Colin R. Simpson,
1,2
Chris Robertson,
3,4
Lewis D. Ritchie,
5
Utkarsh Agrawal,
6
Mark Woolhouse,
1
Josephine L.K. Murray,
4
Helen R. Stagg,
1
Annemarie B. Docherty,
1
Colin McCowan ,
6
Rachael Wood,
1,4
Sarah J. Stock
1
and Aziz Sheikh
1
1
Usher Institute, University of Edinburgh, Edinburgh, UK,
2
School of Health, Wellington Faculty of
Health, Victoria University of Wellington, Wellington, New Zealand,
3
Department of Mathematics and
Statistics, University of Strathclyde, Glasgow, UK,
4
Public Health Scotland, Glasgow and Edinburgh,
UK,
5
Centre of Academic Primary Care, University of Aberdeen, Aberdeen, UK,
6
School of Medicine,
University of St Andrews, St Andrews, UK
*Corresponding author. Usher Institute, University of Edinburgh, NINE Edinburgh BioQuarter, Edinburgh EH16 4UX, UK.
E-mail: eleftheria.vasileiou@ed.ac.uk
Editorial decision 29 January 2021; Accepted 19 February 2021
Why was the cohort set up?
In December 2019, a novel coronavirus COVID-19
emerged from Wuhan, China, and was soon declared as
pandemic by the World Health Organization (WHO) on
the 11 March 2020.
1
The UK soon followed suit and
implemented a national lockdown on the 23 March 2020.
As of 9 December 2020, according to WHO, this highly in-
fectious virus has infected more than 67 million people and
led to over 1.5 million deaths across the world.
2
There is a
growing body of evidence on the epidemiology of the con-
dition, risk factors for poor outcomes and effects of inter-
ventions.
3–9
The rapid generation of robust data is crucial to moni-
tor, understand and mitigate the effects of COVID-19. The
Early Pandemic Evaluation and Enhanced Surveillance of
COVID-19 (EAVE II) database creates a national, real-
time prospective cohort using Scotland’s health data infra-
structure, to describe the epidemiology of COVID-19 in-
fection, patterns of healthcare use and outcomes, and
insights into the effectiveness of and safety of vaccines and
treatments for COVID-19.
10
This work builds on an established cohort for seasonal
and pandemic influenza vaccine and anti-viral assessment
in Scotland EAVE (Early Estimation of Vaccine and Anti-
Viral Effectiveness).
11,12
EAVE is a dormant pandemic
protocol that is part of the National Institute for Health
Research (NIHR) Pandemic Preparedness Research
Portfolio and a platform for previous studies on influenza
vaccine and antiviral assessment.
12–16
Who is in the cohort?
We obtained ethical approval from the National Research
Ethics Service Committee, Southeast Scotland 02.
This prospective baseline cohort study contains all 5.4
million individuals registered with a general practitioner
(GP) in Scotland from 23 February 2020 which, according
to the National Records of Scotland (NRS) 2019 mid-year
V
CThe Author(s) 2021; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association 1
IEA
International Epidemiological Association
International Journal of Epidemiology, 2021, 1–11
doi: 10.1093/ije/dyab028
Cohort Profile
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estimates, covers around 98–99% of the Scottish popula-
tion.
10,17
A map of the baseline EAVE II cohort by the
National Health Service (NHS) Health Board shows that
most of the cohort are based in the central belt of Scotland
(Figure 1).
A summary of the baseline population by sex, age group
(as of 23 February) and deprivation used the Scottish Index
of Multiple Deprivation (SIMD)
18
and Scottish
Government Urban Rural Classification.
19
SIMD is a mea-
sure of deprivation built on seven domains and is unique to
Scotland, with lower quintiles representing the most de-
prived areas.
18
These primary care records are linked to other data
sources from out-of-hours, emergency and secondary care.
There are additional linkages to other datasets such as lab-
oratory testing data, registration and mortality data, self-
reported data and enhanced surveillance data such as the
COVID-19 Clinical Information Network (CO-CIN). This
is done using the Community Health Index (CHI), the
unique identifier provided by NHS Scotland. It is allocated
to all residents in Scotland registered with a GP and to all
patients who receive care in Scotland, even if they are non-
Scottish residents.
10
Summaries of these data sources are
given in Table 2, with a data flow diagram on how they
are linked together in Figure 2.
This cohort therefore consists of specific groups of in-
terest that are used in EAVE II sub-studies such as the
COVID-19 in Pregnancy in Scotland (COPS)
37
and for in-
vestigating ethnic and social inequalities in COVID-19.
How often have they been followed up?
The baseline GP records will be updated on a biannual to
3-monthly basis, if possible. The first update in early 2021
will contain COVID-19-specific GP codes that were cre-
ated during the pandemic and were therefore missed in the
initial extract. This will capture information on COVID-
19 related appointments, vaccinations, therapies and
vaccination-induced adverse effects. Information on influ-
enza will also be included to facilitate analyses on the
effectiveness of and safety of COVID-19-specific and pre-
existing vaccines, therapies and treatments. To facilitate
Figure 1 Baseline Early Pandemic Evaluation and Enhanced
Surveillance of COVID-19 (EAVE II) cohort population by National
Health Service (NHS) Health Board. (1 ¼NHS Ayrshire and Arran;
2¼NHS Borders; 3 ¼NHS Dumfries and Galloway; 4 ¼NHS Forth
Valley; 5 ¼NH S Grampian; 6 ¼NHS Highland; 7 ¼NHS Lothian; 8 ¼NHS
Orkney; 9 ¼NHS Shetland; 10 ¼NHS Western Isles; 11 ¼NHS Fife;
12 ¼NHS Tayside; 13 ¼NHS Greater Glasgow and Clyde; 14 ¼NHS
Lanarkshire ordered by Health board code).
Table 1 Baseline characteristics of the population in the Early
Pandemic Evaluation and Enhanced Surveillance of COVID-
19 (EAVE II) cohort study (n¼5 431 034). Update: 23 February
2020
Characteristics Total number of
individuals (% of total)
Sex
Female 2733477 (50.3)
Male 2697557 (49.7)
Age group (years)
0–4 245423 (4.5)
5–14 574389 (10.6)
15–24 624070 (11.5)
25–44 1479594 (27.2)
45–64 1503617 (27.7)
65–74 563605 (10.4)
75–84 323812 (6.0)
>85 116524 (2.1)
Deprivation quintile
a
1: most deprived 1100521 (20.3)
2 1074842 (19.8)
3 1050369 (19.3)
4 1079282 (19.9)
5: least deprived 1080775 (19.9)
Urban/rural score
b
1: large urban areas 1920932 (35.4)
2: other urban areas 1959281 (36.1)
3: accessible small towns 501557 (9.2)
4: remote small towns 257264 (4.7)
5: accessible rural 486665 (9.0)
6: remote rural 260090 (4.8)
Missing values (%) as below.
a
Deprivation score not available for 45 245 (0.8%) individuals. Score cal-
culated via the Scottish Index of Multiple Deprivation (SIMD).
b
Urban/rural score not available for 45 245 (0.8%) individuals.
c
NHS Health Board not available for 45 245 (0.8%) individuals.
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Table 2 Details of data sources within the different settings for the Early Pandemic Evaluation and Enhanced Surveillance of
COVID-19 (EAVE II) cohort
Setting Data sources Description
Primary care General practice (GP) data
a
Data from all patients registered with GP. GP data (demographic,
consultation data—categorized into risk groups, prescribing and
categorized measurements) will be extracted using the Enhanced
Services Contract Reporting Options (ESCRO) system by the
trusted third party Albasoft Ltd
10
Prescribing Information System
(PIS)
a
Information on all prescribing relating to all prescriptions dispensed
in the community. Prescriptions written in hospitals which are dis-
pensed in the community are also included
20
Out-of-hours (OOH)
b
Data on the services a patient receives for primary care when their reg-
istered GP practice is closed
21
Scottish Morbidity Record 00
(SMR00)
a
Relates to all outpatients (new and follow-up) in specialties other than
Accident & Emergency (A&E), and Genito-urinary Medicine
22
Telephone consultation National Health Service (NHS)
24
a
Delivers telephone and online services across Scotland for initial
assessments, which are then passed on to the appropriate services if
required
10
COVID-19 Community Hubs and
Assessment Centres
b
A network established by NHS Health Boards in Scotland to provide
a direct and rapid route of people with COVID-19
10
. Data from
these centres will derive from National Health Service (NHS) 24
and the COVID-19 Enhanced Surveillance dataset
10
.
Secondary care Scottish Morbidity Record (SMR)
including:
SMR01
a
SMR02
a
SMR01: Episode-based patient record for all inpatients and day cases
discharged from non-obstetric and non-psychiatric specialties in
Scotland. This includes Accident & Emergency (A&E)
attendances
10
SMR02: Episode-based patient record for all inpatients and day cases
discharged from obstetric specialties in Scotland
10
Scottish Hospital Electronic
Prescribing and Medicines
Administration (HEMPA)
system
a
Data on prescription and administration of medicines for inpatients
from a subgroup of hospitals with HEPMA systems
10
Scottish Ambulance Service (SAS)
a
Scottish database for all patients requiring emergency ambulance serv-
ices or needing support to reach their health care appointments due
to their medical and mobility needs
23
Scottish Intensive Care Society
Audit Group (SICSAG)
a
Scottish database for adult patients admitted to all general intensive
care units (ICU) and combined ICU/high dependency units (HDU)
10
COVID19 Clinical Information
Network/International Severe
Acute Respiratory and emerging
Infection Consortium
(CO-CIN/ISARIC)
p
Data of the clinical characteristics of patients admitted to hospital
with COVID-19 infection in Scotland recruited to CO-CIN/
ISARIC.
24
As of 22 June 2020 this comprised 65% of the hospital-
ized patients in Scotland
Rapid Preliminary Inpatient Data
(RAPID)
b
Contains hospital inpatient admission data which have been used to
predict emergency admissions and bed occupancy
25
Mortality data National Records of Scotland
(NRS) deaths
a
Data on Scottish death certificates and the cause of death
26
Laboratory and
serology data
Electronic Communication of
Surveillance in Scotland
(ECOSS)
a
Surveillance data on laboratory results from microorganisms, infec-
tions and microbial intoxications. Contains all reverse transcriptase
polymerase chain reaction (RT-PCR) tests carried out in Scotland
10
Serology data
a
All serology data will be provided by the ‘Seroprevalence’ work car-
ried out and commissioned by the COVID-19 Enhanced
Surveillance cell of Public Health Scotland (PHS)
10
Genome sequencing data
b
Positive laboratory RT-PCR swab samples for COVID-19 will also be
sent to national sequencing centres where 500 COVID-19 genome
sequences will be performed
10
(Continued)
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UK-wide research, QCOVID groups will also be added to
allow validation of the QCOVID ‘living’ risk prediction
model on the Scottish population.
38
Information on
shielded risk groups will also be included to assess the im-
pact of COVID-19 on those most at risk for severe illness
where a 12-month self-isolation was recommended by the
UK government on 23 March 2020.
39
Regular updates on a number of linked datasets and the
underlying GP data will be undertaken on a daily, weekly
or monthly basis, as available and necessary (see Table 3).
Those who have transferred GPs within Scotland will stay
in the cohort. Participants who die or permanently leave
Scotland (and deregister from general practices) will drop
out of the cohort. Characteristics of individuals lost to
follow-up compared with those remaining in the cohort
will also be provided in the study. Missing data will also be
reported for each variable.
What has been measured?
Combining these rich data sources together provides a
wealth of information on the natural history of the condi-
tion and patients’ journeys across Scotland’s NHS. We
provide a high-level summary of key available data in
Table 4.
What has it found?
Permissions to link these datasets were received in May
2020 and the flow of linked data began in June 2020. The
initial GP data extract contained the baseline cohort and
the EAVE II risk groups, which were based on the risk
groups for seasonal influenza, as research at the time of ex-
tract did not know exact risk groups for COVID-19. This
includes comorbidities and household characteristics, for
Table 2 Continued
Setting Data sources Description
Self-reported data Test and Protect data
b
A service which identifies positive cases of COVID-19 and who they
have had close, recent contact with
27
Surveys
b
Surveys on how people have been affected by COVID-19 in Scotland
Census 2011 data
b
Residents in Scotland are asked to fill in a census questionnaire every
10 years and provide information on their demographic (e.g. ethnic-
ity), socioeconomic, health and other circumstances. NRS will pro-
vide data from the latest Scottish Census in 2011
28
Derived data COVID-19 shielding patient list
b
Uses a combination of primary and secondary care held in Public
Health Scotland to derive groups considered to be at high risk if
they contract COVID-19
29
Births and pregnancy-
related data
Scottish Birth Record (SBR)
b
The SBR is a web-based system developed on the NHSNet to ensure
that every baby born in Scotland will have one record which will
act as the foundation for future information collection. The system
has been implemented to varying degrees in all Scottish hospitals
providing midwifery and/or neonatal care
30
NHS live birth notifications
b
Notification of live births from NHS Board maternity units to child
health administration departments
31
NRS births
b
Record of statutory registration of a live birth (live-born baby at any
gestation)
32
NRS statutory stillbirth
registrationsb
Record of statutory registration of a stillbirth (baby born at 24
weeks, showing no signs of life)
33
NHS antenatal care notifications
b
Public Health Scotland (PHS) has developed a new national data re-
turn as part of the response to the COVID-19 pandemic, providing
information on women booking for antenatal care with NHS ma-
ternity services: for identification of women with ongoing pregnan-
cies in near real-time
Abortion Act Scotland (AAS)
Notifications
b
Record of statutory notification of all terminations of pregnancy in
Scotland
34
Vaccine treatment Child Health Systems
Programme—School (CHSP-S)
a
Facilitates the call/recall of both primary and secondary school pupils
for screening, review and immunization
35
Scottish Immunisation Recall
System (SIRS)
b
Data on recorded immunization in children when scheduled for a vac-
cination, including children of pre-school age
36
HEPMA, Hospital Electronic Prescribing and Medicines Administration.
a
Data sources approved as of May 2020.
b
Data sources pursuing.
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example an indicator of living in a care home. This EAVE
II risk group dataset contained more individuals than the
baseline cohort, with over-representation in certain popu-
lations. This is likely to have resulted in residents being
registered at multiple GP practices, people who have left
Scotland or visitors. To overcome this, weights were calcu-
lated by comparing the age and sex profile in the EAVE II
cohort with the age and sex profile for the 2019 NRS mid-
year population estimates in Scotland.
17
A summary of the
number of EAVE II risk groups using these weights is
shown in the Supplementary material, along with the indi-
vidual risk groups (Supplementary Table S1, available as
Supplementary data at IJE online). The following analyses
were performed using these weights.
Initial explorations showed that as age increased, lower
levels of deprivation using SIMD quintiles slightly
Figure 2 Flow diagram for the Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) cohort. Primary care consultations (SMR;
Scottish Morbidity Record; OOH: Out-of-hours); Hospital Admission (SICSAG: Scottish Intensive Care Society Audit Group; CO-CIN: COVID19 Clinical
Information Network; RAPID: Rapid Preliminary Inpatient Data; SAS: Scottish Ambulan ce Service); Prescribing (PIS: Prescribing Information System;
HEMPA: Hospital Electronic Prescribing and Medicines Administration); Laboratory (ECOSS: Electronic Communication of Surveillance in Scotland;
RT-PCR: Reverse transcription polymerase chain reaction); Vaccine Treatment (CHSP-S: Child Health Systems Programme School; SIRS: Scottish
Immunisation Recall System); Birth and Pregnancy (SBR: Scottish Birth Record; NRS: National Records of Scotland; AAS: Abortion Act Scotland).
Table 3 Details on frequency of data linkages
Daily or weekly
linkages
Weekly or
monthly linkages
Monthly
linkages
ECOSS SMR01 SBR
NHS 24 SMR02 NRS births
SAS PIS NRS stillbirths
Serology data NRS deaths NHS antenatal care
SICSAG CO-CIN AAS
RAPID OOH
AAS, Abortion Act Scotland; CO-CIN, COVID-19 Clinical Information
Network; ECOSS, Electronic Communication of Surveillance in Scotland;
NHS, National Health Service; NRS, National Records of Scotland; OOH,
Out-of-hours; PIS, Prescribing Information System; RAPID, Rapid
Preliminary Inpatient Data; SAS, Scottish Ambulance Service; SBR, Scottish
Birth Record; SICSAG, Scottish Intensive Care Society Audit Group; SMR;
Scottish Morbidity Record.
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Table 4 Variables captured and their relevant data sources
Category Variable group Specific variables Source(s)
COVID-19 outcomes Testing Tested; date of positive/negative test; test results; type
of test; antibody tests (if available)
COVID-19 Community Hubs
and Assessment Centres;
ECOSS; serology data; genome
sequencing data; Test and
Protect data
Severity Severity; symptoms; hospital admission; admitted to
ICU; treatment in ICU
NHS 24; COVID-19 Community
Hubs and Assessment Centres;
SMR; SAS; SICSAG; CO-CIN;
RAPID; Test and Protect data;
Surveys; SMR01; SMR00
Mortality Death; cause of death NRS deaths; SMR
Treatment Type of vaccination; date of vaccination GP data; ECOSS;
CHSP-S; SIRS
Potential risk factors Sociodemographic Age; sex; ethnicity; country of birth; BMI; smoking;
employment status; occupation; country of birth;
religion; tenure
GP data; 2011 Census
Geographical Data zone; socioeconomic status (SES) through
Scottish Multiple Deprivation Index (SIMD)
18
;
Urban Rural Index
19
; pollution exposure
40
; popu-
lation density
GP data (use postcode to link to
relevant datasets)
Clinical Comorbidities including chronic respiratory disease
(with chronic obstructive pulmonary disease and
asthma as subsets); chronic heart disease; chronic
liver disease; chronic kidney disease; chronic neuro-
logical disease; diabetes types 1 and 2; conditions
or medications causing impaired immune function;
pregnancy; asplenia or dysfunction of spleen; obe-
sity; hypertension (subsets controlled/uncontrolled
hypertension); tuberculosis; multimorbidity;
Charlson Comorbidity Index
GP data; SMR
Medications Prescription drugs including asthma (including GINA
management steps and oral steroids) and COPD-re-
lated prescriptions; regular inhalers; COVID/pan-
demic acute therapies and chronic therapy for long-
term sequelae; statins; rhinitis therapy; immuno-
therapy; diabetes therapy; cardiovascular disease
therapy; antihypertensives; antibiotics; NSAIDs;
Cox2; paracetamol; antiviral prescriptions; drugs
for previous primary care consultations; polyphar-
macy; high-risk prescribing
GP data; PIS; HEPMA
Pregnancy and babies Pregnancy indicator; miscarriage, ectopic pregnancy,
pregnancy termination (incl. date, gestation,
grounds); stillbirth (incl. date, gestation, cause of
death); live birth (incl. date, gestation, sex of baby);
congenital anomaly flag; neonatal outcomes fol-
lowing maternal infection
GP data; SMR; SICSAG; CO-
CIN; SBR; NHS live birth;
NRS births; NRS stillbirths;
NHS antenatal care; AAS
AAS, Abortion Act Scotland; CO-CIN, COVID-19 Clinical Information Network; ECOSS, Electronic Communication of Surveillance in Scotland; ICU, iten-
sive care unit; NHS, National Health Service; NRS, National Records of Scotland; OOH, Out-of-hours; PIS, Prescribing Information System; RAPID, Rapid
Preliminary Inpatient Data; SAS, Scottish Ambulance Service; SBR, Scottish Birth Record; SICSAG, Scottish Intensive Care Society Audit Group; SMR, Scottish
Morbidity Record; NSAID, non-steroidal anti-inflammatory drug; incl., including; HEPMA, Hospital Electronic Prescribing and Medicines Administration.
6International Journal of Epidemiology, 2021, Vol. 00, No. 00
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increased and the number of risk groups increased (Figure
3). These did not differ substantially between sexes (Figure
3).
Since the first follow-up of COVID-19 outcomes from 1
March to 10 November, there have been a total of 835
803 (15.4%) tested, 57 416 (1.1%) with a positive test
(out of the total cohort), 9847 (0.2%) hospitalized with
COVID-19, 5350 (0.1%) admitted to an intensive care
unit (ICU) or died with COVID-19 on the death certificate
and 4726 (0.1%) who have died with COVID-19 on the
death certificate within the EAVE II cohort. The propor-
tions of these outcomes split by age and sex for the same
time period show that more elderly residents have been
tested with a resulting positive test (Figure 4). Elderly resi-
dents, particularly males, are also more represented in the
more severe outcomes (Figure 4).
These age profiles were repeated for deprivation levels
(using SIMD quintiles), the number of risk groups and the
20 most frequent individual risk groups within the EAVE
II study (Supplementary material). This showed that there
were higher proportions of positive tests and more severe
outcomes in more deprived areas, residents belonging to
multiple risk groups and those who had comorbidities
Figure 3 Baseline Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) cohort population by National Health Service (NHS)
Health Board. (1¼NHS Ayrshire and Arran; 2 ¼NHS Borders; 3 ¼NHS Dumfries and Galloway; 4 ¼NH S Forth Valley; 5 ¼NHS Grampian; 6 ¼NHS
Highland; 7 ¼NHS Lothian; 8 ¼NHS Orkney; 9 ¼NHS Shetland; 10 ¼NHS Western Isles; 11 ¼NHS Fife; 12 ¼NHS Tayside; 13 ¼NHS Greater Glasgow
and Clyde; 14 ¼NHS Lanarkshire ordered by Health board code).
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(Supplementary material, available as Supplementary data
at IJE online).
The map of the proportion of these outcomes by NHS
Health Board demonstrated that despite high rates of test-
ing in more rural areas in the northern and southern parts
of Scotland, positive tests were low (Figure 5). The central
belt had a higher proportion of positive tests out of the to-
tal baseline population and higher rates of more severe
COVID-19 outcomes (Figure 5).
All relevant R code scripts for the summary tables and
figures will be made available on the EAVE II GitHub page
[https://github.com/EAVE-II]. This will also contain a data
dictionary for the entire EAVE cohort which will be
updated when new updates and data linkages are made.
We are currently working on the development of a
national risk prediction algorithm to identify risk factors
for poor outcomes i.e. hospitalisation and death from
COVID-19,
10
and the validation of the QCOVID-19
algorithm.
38
Figure 4 Baseline Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) cohort population by National Health Service (NHS)
Health Board. (1 ¼NHS Ayrshire and Arran; 2 ¼NHS Borders; 3 ¼NHS Dumfries and Galloway; 4 ¼NHS Forth Valley; 5 ¼NHS Grampian; 6 ¼NHS
Highland; 7 ¼NHS Lothian; 8 ¼NHS Orkney; 9 ¼NHS Shetland; 10 ¼NHS Western Isles; 11 ¼NHS Fife; 12 ¼NHS Tayside; 13 ¼NHS Greater Glasgow
and Clyde; 14 ¼NHS Lanarkshire ordered by Health board code).
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What are the main strengths and
weaknesses?
The EAVE II cohort will be widely generalizable to the
Scottish population as it contains all individuals registered
within GP practices in Scotland, with exception of home-
less, itinerant or travelling groups, those in prison, those
who are institutionalized due to mental health reasons and
other reasons. Regularly updating and monitoring this co-
hort over a long period of time will also be quick and cost
effective as the underlying data sources are mainly rou-
tinely collected, quality assured and easily linkable using
unique CHI numbers. This in turn means insights can be
kept up to date with the rapidly evolving pandemic situa-
tion. The completeness and coverage, in terms of both pop-
ulation and breadth of data, are also a major strength.
The key limitations are the possibility of some selection
biases because of excluded patients, although this is
estimated to be under 2% of the Scottish population, and
the risk of residual confounding in the context of analytical
epidemiological studies. Considerable care will need to be
taken when making inferences about the effectiveness of
interventions, because of non-randomized comparisons.
Can I get hold of the data? Where can I find
out more?
Data can be accessed by contacting the corresponding au-
thor. For more information on the cohort, refer to the pub-
lished EAVE II protocol.
10
The study findings will be
presented at international conferences and published in
peer-reviewed journals.
Supplementary Data
Supplementary data are available at IJE online.
Figure 5 Baseline Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) cohort population by National Health Service (NHS)
Health Board. (1 ¼NHS Ayrshire and Arran; 2 ¼NHS Borders; 3 ¼NHS Dumfries and Galloway; 4 ¼NHS Forth Valley; 5 ¼NHS Grampian; 6 ¼NHS
Highland; 7 ¼NHS Lothian; 8 ¼NHS Orkney; 9 ¼NHS Shetland; 10 ¼NHS Western Isles; 11 ¼NHS Fife; 12 ¼NHS Tayside; 13 ¼NHS Greater Glasgow
and Clyde; 14 ¼NHS Lanarkshire ordered by Health board code).
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Author Contributions
A.S. initiated the manuscript. R.H.M. and E.V. led the
writing of the manuscript, and R.H.M. and C.R. led the
analysis. All co-authors reviewed and contributed to the
writing of the manuscript.
Funding
The original EAVE project was funded by the National Institute for
Health Research Health Technology Assessment Programme (proj-
ect number 13/34/14). EAVE II is funded by the Medical Research
Council [MR/R008345/1] and supported by the Scottish
Government. This work is supported by BREATHE—The Health
Data Research Hub for Respiratory Health [MC_PC_19004].
BREATHE is funded through 10 the UK Research and Innovation
Industrial Strategy Challenge Fund and delivered through Health
Data Research UK.
Conflict of interest
Details on competing interests are included in the study’s
protocol [http://dx.doi.org/10.1136/bmjopen-2020-039097].
Remaining co-authors (R.H.M., C.M., U.A., R.W., A.B.D.,
S.J.S.) do not report conflict of interest. A.D. and S.J.S. are
also funded by Wellcome Trust Clinical Career
Development. H.R.S. is supported by the Medical Research
Council (MR/R008345/1).
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Profile in a nutshell
•The Early Pandemic Evaluation and Enhanced
Surveillance of COVID-19 (EAVE II) database creates
a national, real-time prospective cohort using
Scotland’s health data infrastructure, to describe the
epidemiology of COVID-19, patterns of health care
use and outcomes, and insights into the
effectiveness and safety of vaccines and treatments
for COVID-19. As far as we are aware, EAVE II is the
first national end-to-end clinical surveillance platform
for COVID-19 predominantly using routinely available
data.
•This study contains all 5.4 million individuals
registered with a GP in Scotland from 23 February
2020, covering 98–99% of the Scottish population.
These primary care records are linked to other data
sources from out-of-hours, community, emergency
and secondary care, in addition to data on
registrations and mortality, laboratory testing, self-
report and enhanced surveillance.
•These data will be updated throughout the course of
the pandemic. Participants who die or permanently
leave Scotland (and deregister from general
practices) will drop out of the cohort.
•Combining these rich data sources together provides
a wealth of information on the natural history of the
condition and patients’ journeys across Scotland’s
National Health Service (NHS).
•Data will be hosted in Scotland’s National Safe
Haven within the electronic Data Research and
Innovation Service (eDRIS) of Public Health Scotland
(PHS). Applicants must submit an enquiry to the
corresponding author.
10 International Journal of Epidemiology, 2021, Vol. 00, No. 00
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