Ethical aspects of registry-based research in the Nordic countries

Figures & data

Table 1 Key features of ethics committees (ECs) in the Nordic countries

Country	URL	ECs, n*	Members	Election of members	Annual meetings, n
Denmark	http://www.cvk.sum.dk	11+1	Slightly more than half of the regional committee members are laypersons, appointed by the political system, and the other half are medical professionals and active researchers	The National Committee consists of 13 members appointed by the Minister of Health and Prevention	9–11 meetings in each committee
Finland	http://www.tukija.fi	9+1	Medical specialists, biomedical and health researchers, legal specialists, and laypersons (eg, theology, journalism, and political science professionals)	Central EC: members are assigned by the Ministry of Social Affairs and Health and are confirmed by the Finnish Government. Regional ECs: members are assigned by the board of the health care districts.	1–2 meetings/month#
Iceland	http://www.vsn.is	2+1	Individuals with expertise in biomedical sciences, research ethics, human rights, and social science	The Minister of Health and Welfare appoints seven members (and seven deputy members) for a term of 4 years. Members are nominated by the Ministers of Education (one member) and Internal Affairs (one member), the Directorate of Health (one member), the Institute of Ethics at the University of Iceland (one member), and the Faculty of Medicine at the University of Iceland (one member). Two members are appointed directly by the Minister of Health and Welfare	Every 3rd week#
Norway	http://www.etikkom.no	7+1	The National committee consists of 12 members with competence in medical and health research, ethics, and law, in addition to lay representatives The regional ECs consist of nine members, with competence in medical and health research, ethics, and law, in addition to lay representatives	The Research Council of Norway obtains nominees from relevant professional environments and institutions and suggests candidates for the National Committee. The Ministry of Education and Research appoints a chairman, vice-chairman, and members for 4 years. For the regional ECs, the Ministry of Education and Research appoints a chairman, vice-chairman, and members for 4 years	The National Committee meets 5–6 times per year The regional ECs meet 10 times a year
Sweden	http://www.epn.se	6+1	Judicial personnel, medical researchers, and lay representatives	Candidates for the regional ECs are proposed by the medical universities and faculties. The chairman, (always a senior judge) is proposed by the Ministry for Education and Research The members in the Central Review Board are proposed by the National Science Agency (Vetenskapsrådet). The final decision on the composition of the EC is taken by the Swedish Government (Regeringen). Members typically join the EC for 3 years	From once weekly to once monthly#

Notes:

* The number of ECs in each country, and when applicable, the number of central (national) ECs with a potential to overrule regional ECs (typically “+1”). In Iceland, there is a central EC and two subordinates, local ECs pertaining to the two major hospitals in the country;

# different schedules may apply in summer months/vacation.

Table 2 Content of ethics application (EA)

Country	Someone other than the principal investigator (PI) needs to sign the EA	Data key∞	Must be discussed and reported in the EA
			How to store personal data	Power calculation#	Informed consent	Relationship between the researcher and the research subject
Denmark##	No	Yes‡	No	Yes	Yes	No
Finland	No	Yes	Yes	Yes	Yes	Yes
Iceland	No	Yes	Yes	No	Yes	Yes
Norway	Yes*	Yes**	Yes	Yes	Yes	Yes
Sweden	Yes, head of department***	Yes	Yes	Yes	Yes	Yes

Notes:

* In Norway, according to the Health Research Act, medical and health research must be organized as a project under the direction of a person or body responsible for the research. Typically, this will be at an institutional level, and as such, the head of the department, division, or section needs to approve the application;

** some data owners and registries, such as the Norwegian Prescription Registry, do not allow that a key is preserved between a person’s personal identity number (PIN) and the research identifier;

*** to eliminate projects without basic resources, the head of the department must sign the EA to guarantee that the responsible researcher has access to 1) resources adequate to finish the project and 2) a physical workplace from where the project can be conducted;

# the EC requests a power calculation. This calculation ensures that the study does not waste resources (ie, is unethical) and do not waste study participants’ time without being able to answer the main research question;

## in the case of multi-center trials, the investigator should only apply for permission from the regional committee in the area, where the PI carries out the research project;

∞ key between PINs and data can be preserved;

‡ in Denmark, the researchers usually have PINs included in the delivered dataset.

Table 3 Government agencies involved in the management of registry-based data

Country	Name	Name in local language	Area of responsibility
Denmark	Statens Serum Institute, http://www.ssi.dk/English/HealthdataandICT.aspx	Statens Serum Institut	Runs the National Health Surveillance – which supervises many key national health registries
	Statistics Denmark, http://www.dst.dk/en.aspx	Danmarks Statistik	Runs several nationwide registries, such as most demographic databases
	The National Quality Improvement Programme, http://www.rkkp.dk/	Regionernes Kliniske Kvalitetsudviklings-Program (RKKP)	Responsible for all clinical quality registries in Denmark
Finland	National Institute for Health and Welfare, http://www.thl.fi	Terveyden ja Hyvinvoinnin Laitos (THL) Institutet för Hälsa och Välfärd	Social welfare and health care registries and statistics, eg, Medical Birth Registry, Registry of Child Welfare, Care Registry for Health Care, and statistics on morbidity, disability, primary health care services, etc
	Statistics Finland, http://www.stat.fi	Tilastokeskus (Finnish)Statistikcentralen (Swedish)	Combines collected data with its own expertise to produce statistics and information services Statistics on population structure, births and deaths, causes of death, families, education, employment, occupational accidents, etc
	The Social Insurance Institution of Finland, http://www.kela.fi	Kansaneläkelaitos (Kela) Folkpensionsanstalten (Fpa)	Statistics on the rates and incidence of benefits, and their distribution by region and population group. Statistics on occupational health care, prescription medicines and medical expenses, benefits for the families and unemployed, etc
	Population Register Center, http://www.vrk.fi	Väestörekisterikeskus (VRK) Befolkningsregistercentralen	Maintains and develops the Population Information System, a national registry that contains basic information about Finnish citizens and foreign citizens residing permanently in Finland. Personal data recorded in the system includes name, personal identity code, address, citizenship, native language, family relations, occupation, membership in a religious community, and dates of birth and death
Iceland	Directorate of Health in Iceland, http://www.landlaeknir.is/	Embætti Landlæknis	Maintains and is responsible for several national health registries, such as Causes of Death Registry, Medicines Registry, and Patient Registry. Responsible for the Cancer Registry
	Statistics Iceland, http://www.statice.is	Hagstofan	Maintains and is responsible for the Population Registry and other national population statistics
	Icelandic Cancer Registry, http://www.krabbameinsskra.is/	Krabbameinsfélagið	Maintains and runs the Cancer Registry
Norway*	Norwegian Institute of Public Health, http://www.fhi.no	Folkehelseinstituttet	Ten out of 17 national health registries: Cause of death, Medical Birth, Cardiovascular, Prescription, and Abortion Registry in addition to five registries related to infectious diseases control, immunization, and use of antibiotics
	Norwegian Directorate of Health, https://helsedirektoratet.no	Helsedirektoratet	Patient registry, information system for the nursing and care sector, and ePrescription
	The National Archives, http://www.arkivverket.no/arkivverket/Arkivverket/Riksarkivet	Riksarkivene	Health archive registry
	South-Eastern Norway Regional Health Authority, http://www.kreftregisteret.no/ and http://www.oslo-universitetssykehus.no/omoss_/avdelinger_/nyfodtscreening	Helse Sør-Øst	Cancer registry of Norway, Newborn screening programme
	Statistics Norway, http://ssb.no/	Statistisk Sentralbyrå	Registries and databases concerning population, employment, benefits, income, and education
	Regional Health Authorities, http://www.kvalitetsregistre.no	Regionale Helseforetak	National quality registries
Sweden	National Board of Health and Welfare, http://www.socialstyrelsen.se	Socialstyrelsen	Health care registries
	Statistics Sweden, http://www.scb.se	Statistiska Centralbyrån (SCB)	Registries concerning follow-up times (birth, migration, and date of death), relationships between individuals, education, etc. Also responsible for most selection of controls (reference individuals)

Note:

* Use of several of the registries and databases, or specific variables, such as diagnoses, requires approval from the Ministry of Labor and Social Affairs (NAV), National Tax Administration, or Ministry of Education and Research.

Table 4 Outline of the different actors in registry-based research, how potential problems can be overcome, and what each actor stands to gain from registry-based research

Actor	Potential harm	How to address potential harm	Benefits
Study participant/patient*	Identification of study participants Loss of control on which projects personal data are used	Researchers must take all feasible precautions to protect the integrity of patients and to use datasets without personal identifiers Researchers must only conduct research approved by the Ethics committee	Benefits may be as follows: 1) through media interviews, it is possible to inform the public (and patients) of new insights into disease etiology and the natural course of a disease; 2) improved health care; 3) as opposed to intervention studies, registry-based research is usually based on existing data and therefore involves no patient interaction
Health care	When the public hear of research data, their demand for medical testing may increase and this might drain the resources of healthcare providers	Researchers may participate in national health care meetings and may inform health care personnel of recent research findings. Although this requirement will not alleviate the burden of informing those patients who ask questions, it will help other health care personnel to give correct information	Increased knowledge and optimized health care. Registry-based research can help minimize unnecessary investigations and treatment (for example, if researchers can show that a certain investigation does not reduce the risk of a disease, health care practitioners can save time and expenses by decreasing the amount of unnecessary investigation); if researchers can identify medications that decrease the risk of a particular disease, this can save time and expense
Principal investigator (PI), collaborators, and their departments	Time and effort to carry out a project If confidentiality is breached, the breach will have a huge impact on trust and further research for the institutes and the PI	That time and effort are needed to perform a project is a negligible disadvantage, in that researchers conduct projects because they feel they are meaningful and exciting, and because they are being paid to do research Ensure safe, updated and transparent systems for data storage and handling	Increased knowledge New ideas for future research Prestige for the principal investigator and other involved researchers More publications Ability to hire PhD students, postdoctoral students, and other staff that can help with routine tasks. So that researchers can focus on specific tasks that require higher-level skills

Note:

* Also applies to controls matched to “patients” in registry-based research.

Table 5 Attachments to the EA

Research plan (and when possible, information for laypersons) (DEN;# FIN;# ISL;# NOR;# SWE#)

Curriculum vitae for the responsible researcher (DEN;# FIN;# ISL;# NOR;# SWE#)

Certificate from the head of the department that a workplace is available for the researcher (DEN;§ FIN;§ ISL;§ NOR;§ SWE#)

List of participating researchers (DEN;# FIN;# ISL;# NOR;# SWE*)

Advertising material for recruitment of study participants (DEN;# FIN;# ISL;* NOR;# SWE*)

Written study information when informed consent is relevant (DEN;# FIN;# ISL;# NOR;# SWE*)

Copy of the questionnaire or survey if used in the study (DEN;# FIN;# ISL;# NOR;# SWE*)

Description of economic compensation to study participants (DEN;# FIN;# ISL;* NOR;# SWE*)

Copy of contracts if the researcher is hired by a funder (DEN;* FIN;§ ISL;* NOR;* SWE*)

Notes:

* Documents may be submitted as part of the EA;

# documents must always be submitted as part of the EA;

§ not needed. In some Nordic countries, researchers must also submit their own evaluation of ethical dilemmas involved in the project, plus a description of the registry/registries used.

Abbreviations: DEN, Denmark; FIN, Finland; ISL, Iceland; NOR, Norway; SWE, Sweden.

Table 6 Examples of Nordic registry-based studies

Etiology	Article title
Lange et al^Citation50	Lung-function trajectories leading to chronic obstructive pulmonary disease
Larsson and Wolk^Citation51	Dietary fiber intake is inversely associated with stroke incidence in healthy Swedish adults
Bolinder et al^Citation52	Smokeless tobacco use and increased cardiovascular mortality among Swedish construction workers
Naess et al^Citation53	Cardiovascular mortality in relation to birth weight of children and grandchildren in 500,000 Norwegian families
Prognosis
Granlund et al^Citation54	Diverticular disease and the risk of colon cancer – a population-based case-control study
Cantarutti et al^Citation55	Body mass index and mortality in men with prostate cancer
Holm et al^Citation56	Pre-diagnostic alcohol consumption and breast cancer recurrence and mortality: results from a prospective cohort with a wide range of variation in alcohol intake
Kristinsson et al^Citation57	Patterns of survival in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia: a population-based study of 1,555 patients diagnosed in Sweden from 1980 to 2005
Román et al^Citation58	Postmenopausal hormone therapy and the risk of breast cancer in Norway
Therapy
Lichtenstein et al^Citation59	Medication for attention deficit-hyperactivity disorder and criminality
Madsen et al^Citation60	Geographic analysis of the variation in the incidence of attention deficit–hyperactivity disorder (ADHD) in a country with free access to healthcare: a Danish cohort study
Pasternak and Hviid^Citation61	Use of proton-pump inhibitors in early pregnancy and the risk of birth defects
Lund et al^Citation62	Prescription drug use among pregnant women in opioid maintenance treatment
Stephansson et al^Citation44	Selective serotonin reuptake inhibitors during pregnancy and risk of stillbirth and infant mortality
Quality assessment
Vestergaard et al^Citation63	Geographical variation in use of intensive care: a nationwide study
Kristiansen et al^Citation64	Off-hours admission and acute stroke care quality: a nationwide study of performance measures and case-fatality

Table S1 Selected national registries in the Nordic countries

National health registries	Establishment details: year and type of registry	Responsible organization	Information available from registry
Denmark
Danish National Patient Registry (DNPR)^Citation65	1977; outpatient visits at hospitals and emergency room visits have been included since 1995	Statens Serum Institute (SSI)	All admissions to somatic hospitals. Variables include civil registration number, dates of admission and discharge, type of admission, diagnosis codes, procedures, and some types of treatment
The Registry of Medicinal Product Statistics	1994, with complete data from 1995	SSI	All prescribed drugs dispensed by pharmacies in Denmark. Data include civil registration number, product code (Nordic article number), encoding name, form, strength, and pack size, Anatomical Therapeutic Chemical Classification System (ATC) (http://www.whocc.no/atc_ddd_index/), defined daily dose (DDD), and dispensing date
The Danish Medical Birth Registry^Citation66	1973	SSI	For all pregnancies ending in a live or stillbirth: civil registration numbers of the mother and the newborn. Data on the newborn: sex, date of birth multiplicity, birth weight, length, fetal presentation, gestational age, and Apgar score Maternal data: parity and smoking during pregnancy
The Danish Cancer Registry^Citation67,Citation68	1943	SSI	Civil registration number, diagnosis, date of diagnosis, topographical and morphological data, stage, and treatment given within the first 4 months of diagnosis
The Danish Registry of Causes of Death	1970	SSI	Data from the death certificates are completed for all Danish decedents, including civil registration number, causes of death coded as one underlying cause of death, and up to three additional immediate causes (ICD codes), other diseases, and autopsy findings
Danish Psychiatric Central Research Register^Citation69	1969/1995	SSI	Civil registration number, admission and discharge dates, dates of outpatient visits, hospital code, mode of admission (voluntary or compulsory), and all diagnoses Outpatient and emergency room visits at psychiatric hospitals have been included since 1995
Iceland
Cause of Death Registry	1911/1971 (electronic since 2014)	Directorate of Health in Iceland	All deaths are reported by physicians through a death certificate containing cause(s) of death, date of death, age, sex, and residency of deceased; ICD-10 codes (http://www.who.int/classifications/icd/en/) have been included since 1996
Icelandic Medical Birth Register	1972/1981 (electronic since 2014)	Directorate of Health in Iceland	For all pregnancies resulting in stillbirth or live birth after gestational week 22: maternal demographic characteristics and health during pregnancy, complications during and after pregnancy/birth, medicine use in pregnancy, diagnoses, and malformations in child (based on ICD-10 codes and Nordic Medico-Statistical Committee [NOMESCO] Classification of Surgical Procedures) (http://www.nordclass.se/ncsp_e.htm). Information about the father’s occupation and cohabitation with mother, as well as the mother’s occupation
Icelandic Medicines Registry	2003	Directorate of Health in Iceland	Prescription drugs dispensed by pharmacies (including nursing homes/institutions but not hospitals). DDD, package size, ATC codes, Nordic package number, specialty of prescriber, age, sex, and residency of patient, and location of drug dispensing
Cancer Registry of Iceland	1955	Directorate of Health in Iceland, maintained by the Icelandic Cancer Society	Types and morphology of cancers in Iceland. Date of diagnosis (ICD-7, ICD-9, ICD-10, ICD-O3) (http://www.who.int/classifications/icd/en/); patient demographic characteristics; date of cancer-related deaths
Icelandic Patient Registry	1999	Directorate of Health in Iceland	Institution codes, dates of admission and discharge (inpatient only), ICD-10 diagnoses, and procedure codes. Type of admissions, patient demographic characteristics, etc
Finland
Causes of Death Registry	1936	Statistics Finland	The statistics on causes of death are compiled from data obtained from death certificates, which are supplemented with data from the population information system of the Population Registry Center The statistics contain data on deaths and mortality by cause of death, age, sex, marital status, and other demographic variables. The statistics also contain data on the circumstances of death, as well as on perinatal, neonatal, and infant mortality. The annual statistics are compiled by the statistical underlying cause of death. ICD-10 codes since 1996
Medical Birth Registry	1987	National Institute for Health and Welfare (THL)	The registry includes data on live births and stillbirths of fetuses with a birth weight of at least 500 g or with a gestational age of at least 22 weeks, as well as data on the mothers Data sources are maternity hospitals, Population Information System of the Population Registry Center, and Causes of Death Registry Data about the mother, including demographic characteristics, previous pregnancies and deliveries, weight and height before pregnancy, smoking habits, check-ups, diseases, and hospital care during pregnancy and delivery (duration, method of delivery, pain relief, mother’s diagnoses, gestational age, length of stay in hospital) Data about the child, including date and time of birth, sex, weight and length at birth, head circumference, Apgar scores at 1 minute and 5 minutes, pH of umbilical blood, diagnoses, and care interventions by the age of 7 days; there are additional data on small preterm infants
Statistics on reimbursements for prescription medicines	1995	The Social Insurance Institution of Finland (Kela)	The statistics consist of reimbursement data on prescription medicines analyzed statistically according to the date of purchase. All permanent residents of Finland are covered under the Finnish National Health Insurance (NHI) system. All are eligible for reimbursement for the cost of reimbursable medicines prescribed by a doctor or dentist. Only outpatient medication costs are covered. Medication administered in public hospitals is not reimbursable Data content: prescription, purchase of medicine, medicine expenses and reimbursement for medicine expenses, and recipient of a reimbursement with respect to a purchase of medicine Classifications used: ATC classification of medicines, reimbursement category of medicines, diseases conferring an entitlement to a special rate of reimbursement or to medicines with limited reimbursability, physician specialization, general regional classifications, and general demographic classifications
Finnish Cancer Registry	1953	THL	All persons residing in Finland who have developed cancer are registered in the Cancer Registry, as well as the data of those people who form the target population for mass screenings The registry includes personal data (including demographic characteristics), cancer data (primary site of tumor, time of detection, stage, histologic type, primary treatment), and death certificate data of patients, as well as data on mass screenings for breast and cervical cancer (results of screening, results of further examinations, final diagnosis after further examinations)
Care Register for Health Care	1994 (from 1969 to 1993 it was called the Hospital Discharge Registry and only included data on patients discharged from hospitals)	THL	The registry includes data on inpatient care in health centers, hospitals, and other institutions, day surgeries and specialized outpatient care, providers of those services, patients, admission and discharge, diagnoses, and treatments provided. Primary health care is not included here, but these data are kept in the Registry of Primary Health Care Visits Data on start of care (referring party, date of admission, etc), data on treatment (reason for seeking care, diagnoses, type of accident, procedures and interventions, decisions on long-term care, etc), data on discharge (date and further treatment), and some additional data on heart and psychiatric patients (complications and medication, etc)
Norway
Cause of Death Registry (DÅR)	1925/1951	Norwegian Institute of Public Health (NIPH)	All deaths are reported by doctors through a death certificate containing cause(s) of death, date of death, and location of death
Medical Birth Registry of Norway (MBRN)	1967	NIPH	For all pregnancies ending after gestational week 12: maternal health before and during pregnancy, complications during and after pregnancy/birth, medicine use in pregnancy, assisted conceptions, and diagnoses and malformations in child. Information about the father’s occupation and smoking habits, as well as the mother’s occupation and smoking and alcohol habits. Body mass index of mother
Norwegian Prescription Database (NorPD)	2004	NIPH	Prescription drugs dispensed by pharmacies (not hospitals/nursing homes/institutions). Reimbursement codes (ICD-10 codes), prescribed dose, DDD, package size, and ATC codes
Cancer Registry of Norway	1952	South-Eastern Norway Regional Health Authority (Helse Sør-Øst)	Types, stages, and morphology of cancers in Norway. Date of diagnosis (ICD-10). Date of cancer-related deaths
Norwegian Patient Registry (NPR)	1997/2007	Norwegian Directorate of Health	Norwegian specialist health care services (somatic and mental health care, in- and outpatients) with linkable data from 2008 onward. ICD-10 diagnoses and procedure codes. Type of admissions (elective/acute, outpatient/inpatient), etc
Sweden
Swedish Medical	1973	National Board of	The medical birth registry contains antenatal and perinatal data on >98% of all births in Sweden since
Birth Registry		Health and Welfare	1973. Data collection starts at registration for antenatal care, which occurs by the 12th week of gestation in more than 90% of the pregnancies. Since 1982, data are collected prospectively on standardized forms starting at the first prenatal health visit, and variables include smoking
Swedish Patient Registry^Citation70	1964	National Board of Health and Welfare	Complete coverage since 1987. Variables on psychiatric disease were added in 1973. In 1997, data on “day surgery” were added, and in 2001 hospital-based outpatient care was added. Primary health care is not included.
Cause of Death Registry^Citation71,Citation72	1952/1961 (complete since 1961)	National Board of Health and Welfare	Annual mortality reports have been published in Sweden throughout the 20th Century. The National Board of Health and Welfare receives death certificates on >99% of all deaths. Since 1997, the Cause of Death Registry is also matched with the Total Population Registry to ensure that all deaths are recorded. In some (0.5%) of the deaths, no underlying cause of death is reported to the Board; in such cases, the patient is assigned the ICD code R99.9
Cancer Register^Citation73,Citation74	1958	National Board of Health and Welfare	The Cancer Registry started in 1958. Approximately 99% of all cancers are morphologically verified, and approximately 96% are reported to the Cancer Registry. More than 50,000 cancer cases are reported to the Cancer Registry each year. Physicians reporting to the Cancer Registry today report the ICD-10 code, the type and the location of the malignancy in plain text, as well as data on morphology according to the ICD for Oncology (3rd Edition, ICD-O-3)^Citation76 from the pathologist. The Cancer Registry then centrally supplements these data with the corresponding ICD-7 code
Prescribed Drug Register^Citation75	2005	National Board of Health and Welfare	The Prescribed Drug Registry started in 2005 and contains data on expenditures of prescribed drugs. Over-the-counter drugs are not included

Note: A civil registration number is the same as a personal identity number (PIN).

Abbreviations: DDD, defined daily dose; ICD, International Classification of Diseases.

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