National Statistical Institute 

"Health and Justice Statistics" Department

National Statistical Institute
2, P. Volov Str.; 1038 Sofia, Bulgaria

Data on causes of death (CoD) provide information on mortality patterns and form a major element of public health information.

CoD data refer to the underlying cause which - according to the World Health Organisation (WHO) - is "the disease or injury which initiated the train of morbid events leading directly to death, or the circumstances of the accident or violence which produced the fatal injury".

CoD data are derived from death certificates. The information provided in the medical certificate of cause of death is mapped to the International Statistical Classification of Diseases and Related Health Problems (ICD).

Eurostat's CoD statistics build on standards set out by the World Health Organisation (WHO) in the International Statistical Classification of Diseases and Related Health Problems (ICD)

The regional breakdown is based on the Nomenclature of Territorial Units for Statistics (NUTS 2).

Classification and updates applied by years

Public Health

Concepts and definitions are described in the Commission regulation (EU) No 328/2011 in articles 2 and 3.

Main category used in the current demographic statistics is ‘resident population’. This category includes people, who live permanently in the country and have not left it officially as of 31.12. of the respective year for a period more than one year. 

Since 2009 according to Decree No 32 from 30.12.2008 of the Ministry of health, the following definitions about the born children’s status have been applied:

A stillborn child is the one who has not shown signs of life and its weight is 600 and more grams at the completion of pregnancy and/or the pregnancy has continued at least 22 weeks.

According to Decree No 12 from 21.07.2014 on adoption of a medical standard “Midwifery and gynaecology” the following definitions about the born children’s status are applied:

"Birth” is a complete expulsion or extraction from the mother of a foetus, irrespective alive or dead, that meet the following criteria: not

a) body weight at birth of 800 grams and over and / or 26 weeks of gestation;

b) body weight at birth of less than 800 grams and / or less than 26 weeks of gestation - provided that the foetus was born alive and has lived at least 3 days.

"Alive" is a foetus who shows signs of blood circulation. In absence of such signs, the foetus is considered “dead” (foetus mortuus).

Since 2021, according to Decree No 9 from 27.04.2021 г of the Ministry of health, on adoption of a medical standard “Midwifery and gynaecology” the following new  criteria are applied:

"Birth" is a complete expulsion or extraction from the mother of a foetus, irrespective alive or dead, that meet the following criteria:

a) 25 weeks of gestation and/or body weight at birth of 700 grams and over;

b) less than 25 weeks of gestation and /or body weight at birth of less than 700  - provided that the foetus was born alive and has lived at least 72 hours (3 days).

Information on weight, gestational age, and length of the foetus is collected.

The statistical units are the deceased persons and the stillborns, respectively.

Main category used in the current demographic statistics is ‘resident population’. This category includes people, who live permanently in the country and have not left it officially as of 31.12. of the respective year for a period more than one year.

Neonates of non-resident mothers are not included in the national statistics.

According to the requirements set in the Commission regulation n°328/2011, the data on non-residents who died in the country are transmitted to the European Commission.

Non-residents are not included in the national statistics. The main category used in the demographic and COD statistics is ‘resident population’.

Residents dying abroad are included in the national statistics.

The territory of the country.

Time series available from 1995 onwards.

Note that due to the fact that 2011 data is the first data collection with a legal basis (and few changes in the requested variables and breakdowns), the data before and after 2011 are not always comparable (In part due to the different groupings of causes of deaths). Moreover time series for data on stillbirths starts in 2011 and no information on previous data is available.

Not applicable.

The unit is number.

Data refer to the calendar year (i.e. all deaths occurring during the year). 

CoD data was submitted to Eurostat on the basis of a gentleman's agreement established in the framework Eurostat's Working Group on "Public Health Statistics" until data with reference year 2010.

A Regulation on Community statistics on public health and health and safety at work (EC) No 1338/2008 was signed by the European Parliament and the Council on 16 December 2008. This Regulation is the framework of the data collection on the domain.

Within the context of this framework Regulation, a Regulation on Community statistics on public health and health and safety at work, as regards statistics on causes of death (EU) No 328/2011 was signed by the European Parliament and the Council on 5 April 2011. 

CoD data according to this regulation is submitted to Eurostat since reference year 2011.

Law on statistics

Amendment and supplement of Ordinance № 14/2004 of the Ministry of Health on medical criteria and procedures for the establishment of death, publ., SG 41 of 21.05.2019
Ordinance on amendment and supplement of Ordinance 42/2004 of the Ministry of Health on implementation of International Statistical Classification of Diseases and problems related to health - X revision, publ., SG 76 of 23.09.2022.

Common specifications with the World Health Organisation (WHO) were used in the data collection up to 2010; in addition, Eurostat asks for NUTS level 2. From 2011 onwards, Eurostat changed the specifications to take into account the data collected through the Regulation No 328/2011.

Regulation (EC) No 223/2009 on European statistics (recital 24 and Article 20(4)) of 11 March 2009 (OJ L 87, p. 164), stipulates the need to establish common principles and guidelines ensuring the confidentiality of data used for the production of European statistics and the access to those confidential data with due account for technical developments and the requirements of users in a democratic society.

Law on Statistics

Law on Personal Data Protection

The level of detailing of the causes of death as well as the preparation of statistical tables are in accordance with the recommendations of the World Health Organization.

The date of the statistical information release is shown in the Release Calendar presenting the results of the statistical surveys carried out by the Bulgarian National Statistical Institute. Usually the COD data are disseminated 6 months after the end of the reference year.

The calendar is available on the BNSI website: http://www.nsi.bg/en/node/480.

Data on Deaths by causes and mortality by causes is published on the BNSI website, section Health in accordance with the Law on Statistics and the European Statistics Code of Practice respecting the professional independence and aimed at objectivity, transparency and equal treatment of all consumers.

Annually.

Not applicable.

Data on Deaths by causes are published annually in the following national publications:

• Health Services;
• Statistical yearbook;
• Population and Demographic Processes.

CoD data are available to all users of the BNSI website under the heading Health - Deaths by causes and mortality by causes: http://www.nsi.bg/en/node/5614;

INFOSTAT - Information System for online requests for statistical information: https://infostat.nsi.bg/infostat/pages/module.jsf?x_2=61

Information not available. 

Anonymised individual data can be provide for scientific and research purposes according to the Rules for Provision of Anonymised Individual Data for Scientific and Research Purposes of the BNSI.

Information service on request can be provide according to the Rules for Dissemination of Statistical Products and Services of the NSI.

Information not available.

Methodological notes are available at http://www.nsi.bg/sites/default/files/files/metadata/Zdr_6_Methodology_EN.pdf;

International Statistical Classification of Diseases and Related Health Problems (ICD) - X rev.

100%

The quality of information on deaths by causes and mortality by causes are mainly determined by:

• the information filled in by the physician - certifier;
• implementation of the rules for selection and coding of the underlying cause of death;
• strict application of all validation rules during the process of statistical information production.

In the performance of its functions, the NSI organizes joint trainings of experts from Regional Health Inspections and Regional Statistical Offices, who work in the field of COD statistics in order to improve the quality of data.

Integrated quality and security management system has been implemented in accordance with the requirements of BDS EN ISO 9001: 2015 and BDS EN ISO 27001: 2017. The certificate fully meets all international requirements and guarantees the quality of the processes and information security of the entire statistical and information infrastructure of the NSI, both at national and regional levels.

Strict implementation of the WHO requirements and the rules and instructions for certification and coding according to ICD - X rev., annual logical control of data in accordance with ICD - X rev. and implementation of the Eurostat recommendations are a prerequisite for a high data quality.

Integrated quality and security management system has been implemented in accordance with the requirements of BDS EN ISO 9001: 2015 and BDS EN ISO 27001: 2017. The certificate fully meets all international requirements and guarantees the quality of the processes and information security of the entire statistical and information infrastructure of the NSI, both at national and regional levels.

Data on causes of death are provided annually to Eurostat and World Health Organization (WHO) in strict compliance with the prescribed terms and forms of presentation of the data. In the framework of regular annual questionnaires data are also provided to other European and international organizations - UNESCO, UNICEF, etc. Users of health information at national and regional level are the National Assembly of the Republic of Bulgaria, the executive and local authorities, National Health Insurance Fund. The data are provided annually to the National Centre for Public Health and Analysis at the Ministry of Health, Ministry of Health and its territorial units - Regional Health Inspections, whose functions are to implement and organize the government health policy at national and regional level.

Upon request data is provided to research institutes, universities, NGOs and other users.

Not available.

All the requirements set out in the Regulation on Community statistics on public health and health and safety at work as regards statistics on causes of death (EU) No 328/2011 are fulfilled.

1. For mandatory variables:

 100% - All variables required by the Commission regulation n°328/2011 are transmitted to the European Commission.

2. For voluntary variables:

 All voluntary variables required by the Commission regulation n°328/2011 are transmitted to the European Commission except Region of occurrence (NUTS 2) for residents dying abroad. In these cases the eligible information is only for the country of occurrence of death. In 2020, 1.5% of the deceased BG residents died abroad.

3. For additional variables:

• External CoD

For all reported external causes of death the specific injury and poisoning ICD code (Chapter XIX, S-T codes) is provided.

• Place of occurrence for external CoD

Not applicable. ICD-X without updates is used.

• Activity for external CoD

Not applicable. ICD-X without updates is used.

Exhaustive survey. No reasons for any unreliability of the data. 

Not applicable. Data collection is from administrative sources.

Not applicable.

Not applicable.

Administrative data source is used for production of official statistics. Computer data files are provided to NSI from the Unified System for Civil registration and Administrative Service of Population with information on all demographic events. The use of administrative sources for carrying out the CoD statistics garantees the full coverage.

Not applicable.

Not applicable. Data collection is from administrative sources.

Data validation is performed - criteria for doubling, correctness, validation rules for each record’s characteristic incl. potential inconsistency in the death certificate or error due to mistake when filling the deaths certificates are applied. In case of inconsistencies or errors, the physician who codes and/ or certifier should be contacted.

An estimation is not available.

There is no cases of unit non-response.

Item non-response: In 2021 the country of occurance is unknown for 0.2% of all residents who died abroad and the residency region is unknown for 100% of non-residents who died in the country.

No cases.

Unknown country of occurance for residents who died abroud  (%)

2021 - 0.2% of all residents who died abroud;

2020 – 0.1% of all residents who died abroud;

2019 - no cases;

2018 – 0.3% of all residents who died abroud;

2017 – 0.4% of all residents who died abroud;

2016 – no cases;

2015 – 0.1% of all residents who died abroud;

2014 – 0.4% of all residents who died abroud.

Unknown region for non-residents who died in the country (%)

2021 - 100% unknown residency region for non-residents who died in the country;

2020 - 100% unknown residency region for non-residents who died in the country;

2019 - 100% unknown residency region for non-residents who died in the country;

2018 – 100% unknown residency region for non-residents who died in the country;

2017 – 100% unknown residency region for non-residents who died in the country;

2016 - 100% unknown residency region for non-residents who died in the country;

2015 - 100% unknown residency region for non-residents who died in the country;

2014 - 100% unknown residency region for non-residents who died in the country.

Data validation is performed - criteria for doubling, correctness, validation rules for each record’s characteristic incl. potential inconsistency in the death certificate are applied. In case of inconsistencies or errors, the physician who codes and/ or certifier should be contacted.

An estimation is not available.

Not applicable.

Not applicable.

Not applicable.

From data collection with reference year 2011 onwards, Eurostat asks for the submission of final data at national and regional level and related metadata for the year N at N+24 months, according to the Implementing Regulation (EC) No. 328/2011, Article 4.

At national level the data are comparable for all territorial regions in the country. The process of collecting, coding and transmission of the data is the same for all regions.

In accordance with the WHO guidelines, codes I46.0 Cardiac arrest with successful resuscitation and I46.9 Cardiac arrest unspecified should not be used as underlying cause of death, and this change come into force on 1 January 2019. Since 2020 reference year, Eurostat recoded the both codes automatically to R99 xxx in order data comparability to be achieved.

In Bulgaria I46.0 and I46.9 had been used as underlying cause of death up to 31.12.2020. For this reason, there is a discrepancy between the 2020 data disseminated by Eurostat and BNSI in respect to chapters IX Diseases of the circulatory system and XVIII Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified.

Not applicable.

The data are comparable. Procedures for data collection, coding of cause of death and production of statistical data are the same for the whole period. 

2011-2021

At national level full coherence is enshured.

The total number of deaths by causes is equal to the number of deaths (stillbirths) in the demographic statistics.

Eurostat dessimination practice

The total number of deaths by causes and stillbirths disseminated by Eurostat (health) is not equal to the number of deaths (stillbirths) in the demographic statistics as well as the national COD data.

The main category used in the demographic and COD statistics is ‘resident population’. The total number of deaths includes all deceased residents of BG during the respective year (incl. residents dying abroad all over the world). Non-residents are not included.

The discrepancies with the demographic mortality tables are due to the different methodology used:

• inclusion of non-residents deaths into Eurostat health tables 'All deaths reported in the country'  
• inclusion of deaths occured at EU territory only, but not outside EU, reported by separate countries.

Not applicable, only annual data are available.

Not applicable.

At national level full coherence is enshured.

There are no inconsistencies between the neonates information provided in the General mortality dataset and in the Stillbirths and neonates dataset.

The cost and burden of the data collection is reduced by using validation and dissemination IT tools.

Revision of published data is possible after validation procedure in accordance with the Regulation (EU) 328/2011 requirements. In addition, revision is possible due to change in statistical regions (NUTS 2). 

There is no systematic revision of previous year data. 

Not applicable.

Data source for all demographic events is a National civil registration system.

The events are registered by following document:

· Death Certificate - for deaths;

· Birth Certificate - for stillbirths.

Events information is obtained as an electronic file. Causes of death and stillbirth are coded on a paper document by physicians, working in Regional Health Inspections, specially trained for that. Copies of these paper documents are supplied to the Regional Statistical Offices where codes are entered into Information System "Demography".

Annual.

1. Certification

Data source on causes of death statistics is the medical certificate of death. The form and content of the document are determined by the Ordinance № 42 of 8 December 2004 the Minister of Health, as the part of the causes of death and other medical information is standardized in accordance with the recommendations of the World Health Organization (WHO).

The death certificate is filled in by the physician who recognized the death in accordance with the Amendment and supplement of Ordinance № 14/2004 of the Ministry of Health on medical criteria and procedures for the identifying death, publ., SG 41 of 21.05.2019. The national legislation determines in details all the procedures and medical criteria needed in order to identify the person as deceased 

Supervision and control of the certification process is carried out by experts in Regional health inspections occasionally or ad hoc on a specific issue.

The training in certification is part of the medical education.

2. Coding

Automated coding is not used, manual selection of underlying cause is applied. Only information on the underlying cause is stored in the national COD database.

Table on certification (Percentage)

¹ Percentage of certificates filled in by pathologist. 

Data source for stillbirths is the certificate of birth. The certificate is filled in in health establishment and in case of stillbirth one copy is submitted to the Regional health inspections. Coding of causes of stillbirths (as well as deaths) is performed by doctors working in Regional health inspections, specially trained for this purpose.

The neonatal deaths are coded as all other deaths.

Data validation is performed at three stages:

• At data transmission – preliminary checking and processing, the proper application of the criterion for length of stay of 12 months.
• At the data processing stage - criteria for doubling, correctness, validation rules for each record’s characteristic.
• Before data release - checking the frequencies of separate variables, consistency of table and cross-tabulations.

Administrative data source is used for validation of the coverage. Data source for all demographic events is the National civil registration system.

Description of coding procedure (central level, distributed among other bodies, etc.):

The coding of underlying cause of death is carried out by physicians working in Regional Health Inspections, specially trained to implement the requirements of the International Classification of Diseases - X revision. The Regional Health Inspections implement and organize the government health policy within the territory of administrative regions. There are 28 Regional Healthcare Inspections in the country.

After coding the documents are submitted to the Regional Statistical Offices for entering the information. The data is processed and stored in IS "Demography".

Description of the procedures to detect errors (i.e. errors such as potential inconsistency in the death certificate or error due to mistake when filling the deaths certificates):

At stage of coding - physician who codes the cause of death must review the medical information in the death certificate, and in cases it is not filled in correctly, he/she is obliged to contact the physician, who has issued a death certificate for further specifications.

At data transmission – preliminary checking and processing, the proper application of the criterion for length of stay of 12 months.

At the data processing stage - criteria for doubling, correctness, validation rules for each record’s characteristic incl. potential inconsistency in the death certificate or error due to mistake when filling the deaths certificates. In case of inconsistencies or errors, the physician who codes and/ or certifier should be contacted.

Description of the measures taken in order to solve detected errors:

In case of inconsistencies or errors, the certifier/ physician who codes should be contacted.

Coding performed by a certifier:

The coding is not performed by a certifier. The coding of underlying cause of death is carried out by physicians working in Regional Health Inspections, specially trained to implement the requirements of the International Classification of Diseases - X revision.

Estimation of the percentage of autopsy from which information is available for coding:

Non available

Description of double coding exercises and rate of codification errors for underlying cause of death:

There are no double coding exercises performed.

ICD codes for the underlying cause (% of the Total)

Unknown country/region (%) for residents and non-residents who died in the country

Administrative data sources are used for validation of the coverage Data source for all demographic events is the National civil registration system. Events information is obtained as an electronic file. Causes of death and stillbirth are coded on a paper documents, a copy of which is also obtained. In case of stillbirth as well as death of a child up to 168 hours of his/her birth a certificate for perinatal death is filled in and send to the Regional health inspections. The last is used to verify data on perinatal mortality.

Not applicable.

Not applicable.

Not applicable.

Not applicable.