Disease classification: measuring the effect of the Tenth Revision of the International Classification of Diseases on cause-of-death data in the United States

The purpose of this paper is to describe the statistical impact of the Tenth Revision of the International Classification of Diseases (ICD-10) on cause-of-death data for the United States. ICD-10 was implemented in the U.S. effective with deaths occurring in 1999. The paper is based on cause-of-death information from a large sample of 1996 death certificates filed in the 50 States and the District of Columbia. Cause-of-death information in the sample includes underlying cause of death classified by both ICD-9 and ICD-10. Preliminary comparability ratios by cause of death presented in this paper indicate the extent of discontinuities in cause-of-death trends from 1998 to 1999 resulting from implementing ICD-10. For some leading causes (for example, septicaemia, influenza and pneumonia, Alzheimer's disease, and nephritis, nephrotic syndrome and nephrosis) the discontinuity in trend is substantial. Results of this study, although preliminary, are essential to analysing trends in mortality statistics between ICD-9 and ICD-10. In particular, the results provide a means for interpreting changes between 1998, which is the last year in which ICD-9 was used, and 1999, the year in which ICD-10 was implemented for mortality in the United States. Published in 2003 by John Wiley & Sons, Ltd.     

Comparability between ICD-9 and ICD-10 for the leading causes of death in Spain

BACKGROUND: Implementation of a new Revision of the International Classification of Diseases can create discontinuity in mortality statistics. Revisions are nevertheless essential to ensure international comparability of health statistics. The purpose of this work was to describe the effects of the 10th Revision on mortality statistics by sex and age for leading causes of death in Spain. METHODS: A cross-sectional study of leading causes of death was carried out when the underlying cause of death was coded using both the 9th and 10th Revisions of the International Classification of Diseases in 88,044 death certificates completed in five Autonomous Communities of Spain (Andalusia, Cantabria, Murcia, Navarra, the Basque Country), and the city of Barcelona during the year 1999. Changes introduced by the 10th Revision were described by simple correspondence, percentage of change, Kappa index and comparability ratios between the 10th and the 9th Revision along with their 95% confidence intervals by sex and five-year age group, for the leading causes of death. RESULTS: Under the 10th Revision, AIDS deaths rose by 3.6% (comparability ratio (CR): 1.036; 95% confidence interval (CI):1.015-1.058), arteriosclerosis by 7.1% (CR: 1.071; 95% CI: 1.052-1.090), and drug overdose by 5.2% (CR: 1.052; 95% CI: 0.964-1.140). Mortality due to vascular and senile dementia and non specific dementia declined by 3.2% under the 10th (CR: 0.969; 95% CI: 0.950-0.988). In all the other causes of death the percentage of change regardless of direction was less than 2%. CONCLUSION: The present study found good agreement between ICD-9 and ICD-10 on the leading causes of death and premature mortality in Spain. Causes of death which present differences between Revisions were AIDS, arteriosclerosis, drug overdose and senile dementia. For these causes, the comparability ratios must be taken into account when interpreting mortality statistics.     

Deaths: final data for 1999.

OBJECTIVES: This report presents final 1999 data on U.S. deaths and death rates according to demographic and medical characteristics. Trends and patterns in general mortality, life expectancy, and infant and maternal mortality are also described. A previous report presented preliminary mortality data for 1999. METHODS: In 1999 a total of 2,391,399 deaths were reported in the United States. This report presents tabulations of information reported on the death certificates completed by funeral directors, attending physicians, medical examiners, and coroners. Original records are filed in the State registration offices. Statistical information is compiled into a national data base through the Vital Statistics Cooperative Program of the National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention. For the first time in a final mortality data report, age-adjusted death rates are based upon the year 2000 population and causes of death are processed in accordance with the Tenth Revision of the International Classification of Diseases (ICD-10). RESULTS: The 1999 age-adjusted death rate for the United States was 881.9 deaths per 100,000 standard population, a 0.7 percent increase from the 1998 rate, and life expectancy at birth remained the same at 76.7 years. For all causes of death, age-specific death rates rose for those 45-54 years, 75-84 years, and 85 years and over and declined for a number of age groups including those 5-14 years, 55-64 years, and 65-74 years. Aortic aneurysm and dissection made its debut in the list of leading causes of death and atherosclerosis exited from the list. Heart disease and cancer continued to be the leading and second leading causes of death. The age-adjusted death rate for firearm injuries decreased for the sixth consecutive year, declining 6.2 percent between 1998 and 1999. The infant mortality rate, 7.1 infant deaths per 1,000 live births, was not statistically different from the rate in 1998. CONCLUSIONS: Generally, mortality continued long-term trends. Life expectancy in 1999 was unchanged from 1998 despite a slight increase in the age-adjusted death rate from the record low achieved in 1998. Although statistically unchanged from 1998, the trend in infant mortality has been of a steady but slowing decline. Some mortality measures for women and persons 85 years and over worsened between 1998 and 1999.     

Deaths: leading causes for 1999.

OBJECTIVES: This report presents final 1999 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics and responds to an increasing volume of requests by data users for leading-cause tables with more age and race detail than previously published. METHODS: Data in this report are based on information from all death certificates filed in the 50 States and the District of Columbia in 1999. Causes of death classified by the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. Age categories used to present leading causes of death in this report represent a substantial expansion from the age categories previously used to present leading-cause data in the annual report of final mortality statistics. RESULTS: In 1999 the 10 leading causes of death were (in rank order) Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents; Diabetes mellitus; Influenza and pneumonia; Alzheimer's disease; Nephritis, nephrotic syndrome, and nephrosis; and Septicemia and accounted for nearly 80 percent of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 1999 were (in rank order) Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birthweight, not elsewhere classified; Sudden infant death syndrome; newborn affected by maternal complications of pregnancy; Respiratory distress of newborn; Newborn affected by complications of placenta, cord, and membranes; Accidents; Bacterial sepsis of newborn; Diseases of the circulatory system; and Atelectasis. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.     

Converting ICD-9 to ICD-10

Implementing the International Classification of Diseases, Ninth Revision (ICD-9) to International Classification of Diseases, Tenth Revision (ICD-10) conversion on October 1, 2015, in the United States has been a long-term goal. While most countries in the world converted more than 10 years ago, the United States was still using ICD-9. Many countries in the world have a single-payer healthcare system, while there are thousands of different healthcare organizations (providers and payers) that presently exist in the United States. With so many different software platforms for healthcare providers and payers, the conversion had become that much more complicated and capital intensive for all healthcare organizations in the country. A few of the present delay reasons to the ICD-10 conversion in past years were the concurrent timelines for meeting meaningful use requirements for the electronic health record, testing with external payers and upgrades from vendors which added complexities and extra costs. The authors examine the reasoning behind the conversion as well as the delays, before making the conversion on October 1, 2015, and review the question regarding whether the government's decision to push the date back a year would have been helpful.     

Deaths: leading causes for 2002.

OBJECTIVES: This report presents final 2002 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics. METHODS: Data in this report are based on information from all death certificates filed in the 50 States and the District of Columbia in 2002. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. RESULTS: In 2002, the 10 leading causes of death were (in rank order) Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents (unintentional injuries); Diabetes mellitus; Influenza and pneumonia; Alzheimer's disease; Nephritis, nephrotic syndrome and nephrosis; and Septicemia and accounted for about 79 percent of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2002 were (in rank order) Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birthweight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Newborn affected by complications of placenta, cord and membranes; Accidents (unintentional injuries); Respiratory distress of newborn; Bacterial sepsis of newborn; Diseases of the circulatory system; and Intrauterine hypoxia and birth asphyxia. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.     

Deaths: leading causes for 2000.

OBJECTIVES: This report presents final 2000 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics. METHODS: Data in this report are based on information from all death certificates filed in the 50 States and the District of Columbia in 2000. Causes of death classified by the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. RESULTS: In 2000 the 10 leading causes of death were (in rank order) Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents (unintentional injuries); Diabetes mellitus; Influenza and pneumonia; Alzheimer's disease; Nephritis, nephrotic syndrome and nephrosis; and Septicemia and accounted for nearly 80 percent of all deaths occurring in the United States. Differences in the rankings are evidently by age, sex, race, and Hispanic origin. Leading causes of infant death for 2000 were (in rank order) Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birthweight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Newborn affected by complications of placenta, cord and membranes; Respiratory distress of newborn; Accidents (unintentional injuries); Bacterial sepsis of newborn; Diseases of the circulatory system; and Intrauterine hypoxia and birth asphyxia. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.     

Deaths: leading causes for 2003.

OBJECTIVES: This report presents final 2003 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics. METHODS: Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2003. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. RESULTS: In 2003, the 10 leading causes of death were (in rank order): Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents (unintentional injuries); Diabetes mellitus; Influenza and pneumonia; Alzheimer's disease; Nephritis, nephrotic syndrome and nephrosis; and Septicemia and accounted for about 78 percent of all deaths occurring in the United States. Differences in the ranking are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2003 were (in rank order): Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Newborn affected by complications of placenta, cord and membranes; Accidents (unintentional injuries); Respiratory distress of newborn; Bacterial sepsis of newborn; Neonatal hemorrhage; and Diseases of the circulatory system. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.     

Infant Mortality: Development of a Proposed Update to the Dollfus Classification of Infant Deaths

Objective

Identifying infant deaths with common underlying causes and potential intervention points is critical to infant mortality surveillance and the development of prevention strategies. We constructed an International Classification of Diseases 10th Revision (ICD-10) parallel to the Dollfus cause-of-death classification scheme first published in 1990, which organized infant deaths by etiology and their amenability to prevention efforts.

Methods

Infant death records for 1996, dual-coded to the ICD Ninth Revision (ICD-9) and ICD-10, were obtained from the CDC public-use multiple-cause-of-death file on comparability between ICD-9 and ICD-10. We used the underlying cause of death to group 27,821 infant deaths into the nine categories of the ICD-9-based update to Dollfus'' original coding scheme, published by Sowards in 1999. Comparability ratios were computed to measure concordance between ICD versions.

Results

The Dollfus classification system updated with ICD-10 codes had limited agreement with the 1999 modified classification system. Although prematurity, congenital malformations, Sudden Infant Death Syndrome, and obstetric conditions were the first through fourth most common causes of infant death under both systems, most comparability ratios were significantly different from one system to the other.

Conclusion

The Dollfus classification system can be adapted for use with ICD-10 codes to create a comprehensive, etiology-based profile of infant deaths. The potential benefits of using Dollfus logic to guide perinatal mortality reduction strategies, particularly to maternal and child health programs and other initiatives focused on improving infant health, warrant further examination of this method''s use in perinatal mortality surveillance.The International Classification of Diseases (ICD), published by the World Health Organization (WHO), serves as the standard for morbidity and mortality classification. Volume two of the ICD 10th revision (ICD-10) provides the structure used to collect, classify, process, and present mortality statistics over time and across geographic regions,^1,2 using a taxonomy that classifies deaths by general disease and affected organ or site. To ensure consistency in the presentation of mortality data across nations, WHO statisticians and medical officers create special tabulation lists with each revision of the ICD. These lists, modified for use in the United States by the Centers for Disease Control and Prevention (CDC), National Center for Health Statistics (NCHS), aggregate thousands of single underlying cause-of-death codes into meaningful categories that take into consideration the cause group''s amenability to public health interventions. In the United States, NCHS''s List of 130 Selected Causes of Infant Death is the longstanding method for aggregating cause codes for infant mortality surveillance.³ One challenge of adapting this list to the statistical study of infant mortality is that contiguous code blocks do not necessarily reflect common etiologies.^4–6Alternative classification schemes for infant mortality have been proposed to improve the utility of the ICD underlying cause-of-death code groups for targeted public health efforts. Isolation of prematurity-related deaths, for example, has been a particular challenge for infant mortality surveillance.^6–9 To more accurately reflect deaths caused directly or indirectly by prematurity, NCHS has begun tracking preterm-related mortality using selected cause codes originally identified through a clinical and literature review of 20 leading causes of infant death.^5,10,11 Although this measure is specific to the impact of prematurity on infant mortality, by combining conditions from different sections of the ICD into one with a common set of health determinants, it is an example of the kind of causal grouping critical to health assessment and prevention efforts.The Dollfus classification system, published in 1990 by researchers from the University of North Carolina at Chapel Hill and the North Carolina Center for Health Statistics, aggregates infant deaths based on common etiology and their amenability to prevention strategies⁴ into eight mutually exclusive groups: prematurity and related conditions, congenital anomalies, Sudden Infant Death Syndrome (SIDS), obstetric conditions, birth asphyxia, perinatal infections, other infections, and external causes. In 2013, the State Infant Mortality Toolkit, developed through a collaboration among CDC, the Association of Maternal and Child Health Programs, the March of Dimes, and state and national experts in maternal and infant health, emphasized the importance of infant cause-of-death grouping, including Dollfus classification, to assess infant mortality.¹² This toolkit provides an analytical framework that is useful for Collaborative Improvement and Innovation Network (CoIIN) efforts directed toward infant mortality reduction,¹³ Health Resources and Services Administration''s Title V Maternal and Child Health program needs assessment,¹⁴ and other initiatives to improve birth outcomes.¹⁵ The toolkit examined comparability of Dollfus classification using published data aggregated into 130 rankable causes of infant death under ICD Ninth Revision (ICD-9) and ICD-10, cautioning that classification systems are limited by the quality of underlying cause-of-death data. Our method builds upon that earlier work, employing a statistical frequency-based approach applied to individual bridge-coded death records coded under both ICD versions.The most recent update to the original Dollfus classification was published in 1999, when Sowards updated the system to facilitate its use with national data,¹⁶ presenting a modified Dollfus classification built according to cause-of-death coding published in ICD-9. To date, a validated ICD-10 equivalent to the original logic employed by Dollfus et al. has yet to be published. We describe a mapping of Sowards'' 1999 Modified Dollfus Classification Scheme for Causes of Infant Death (hereinafter, 1999 Modified Dollfus Scheme)¹⁷ from ICD-9 to ICD-10 codes.     

Deaths: leading causes for 2004.

OBJECTIVES: This report presents final 2004 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics. METHODS: Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2004. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. RESULTS: In 2004, the 10 leading causes of death were (in rank order) Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents (unintentional injuries); Diabetes mellitus; Alzheimer's disease; Influenza and pneumonia; Nephritis, nephrotic syndrome and nephrosis; and Septicemia and accounted for about 78 percent of all deaths occurring in the United States. Differences in the ranking are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2004 were (in rank order) Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Accidents (unintentional injuries); Newborn affected by complications of placenta, cord and membranes; Respiratory distress of newborn; Bacterial sepsis of newborn; Neonatal hemorrhage; and Diseases of the circulatory system. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.     

Deaths: injuries, 2002.

OBJECTIVES: This report presents injury mortality data for 2002 using the external-cause-of-injury mortality matrix for the International Classification of Diseases, Tenth Revision (ICD-10). The external cause matrix is a detailed and comprehensive framework for tabulating and presenting injury deaths by mechanism and intent of death. Data are presented by age, sex, race, Hispanic origin, and State. In addition, trend data are shown for 1999-2002 by age, sex, and mechanism and intent of injury. This report also introduces the injury mortality diagnosis matrix. This latter is another framework that categorizes the nearly 1,200 injury diagnosis codes from ICD-10's chapter 19 according to body region and nature of the injury diagnosis information captured in the multiple-cause-of-death fields of the national mortality file. This report supplements the annual report of final mortality statistics. METHODS: Data in this report are based on information from all death certificates filed in the 50 States and the District of Columbia in 2002. Causes of death and nature of injury are processed and coded in accordance with the ICD-10. RESULTS: In 2002, 161,269 resident deaths occurred as the result of injuries. Of these injury deaths, 66.2 percent were classified as unintentional, 19.6 percent were suicides, 10.9 percent were homicides, 3.0 percent were of undetermined intent, and 0.3 percent involved legal intervention or operations of war. The five leading mechanisms of injury death were motor vehicle traffic, firearm, poisoning, falls, and suffocation, accounting for 81 percent of all injury deaths. The rate of poisoning deaths increased by 17.9 percent between 2001 and 2002, but the reader is advised to interpret these numbers cautiously as a portion of this increase is due to stricter procedures concerning data processing that were implemented in 2002. Thirty percent of injuries resulting in death were to the head and neck region with the vast majority of these classified as traumatic brain injury. Injuries involving the whole body system accounted for 28 percent of all injuries mentioned (17 percent were poisoning and 7 percent were other effects of external causes, such as submersion or asphyxiation). CONCLUSIONS: Injury mortality data presented in this report using the external cause-of-injury mortality matrix for ICD-10 provide detail on the mechanism of death needed for research and other activities related to injury prevention. This report highlights the importance of multiple causes-of-death data when analyzing injury mortality--special attention is given to the issue of accuracy and completeness of information as it pertains to these data. The Centers for Disease Control and Prevention's (CDC) National Center for Health Statistics (NCHS) is involved in several ongoing projects related to the study of injury and injury mortality.     

2001-2010年上海市卢湾区居民心脑血管疾病死亡动态分析

目的 分析上海市卢湾区居民心脑血管疾病死亡变化及趋势,为进一步制定心脑血管疾病防治策略提供科学依据.方法 统计分析2001-2010年卢湾区户籍人口心脑血管疾病死亡及人口监测资料.2001年的死因分类按国际疾病分类法ICD-9,2002-2010年按国际疾病分类法ICD-10标准进行分类.用2000年全国人口构成进行标化率计算,进一步计算心脑血管疾病潜在减寿年数.结果 2001-2010年,上海市卢湾区户籍人口心脑血管疾病死亡率总体呈波动性下降趋势,其中脑血管疾病死亡率下降趋势较为明显,但随年龄增长呈几何级数增高.10年间,心脑血管疾病一直占据全人群死因顺位的第1位,死因减寿顺位的第2、3位.结论 心脑血管疾病已成为上海市卢湾区居民的主要死亡原因,全社会必须重视这类慢性病的预防.同时,应重点加强对60岁以上这部分年龄组人群心脑血管疾病的控制和预防.     

Implications of the ICD-10 definitions related to death in pregnancy, childbirth or the puerperium

The Tenth Revision of the International Classification of Diseases (ICD-10) will include two new definitions concerning death related to pregnancy: --Late maternal death--the death of a woman from direct or indirect obstetric causes more than 42 days but less than one year after termination of pregnancy. --Pregnancy-related death--the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the cause of death. This article discusses the rationale underlying these definitions and their implications for public health statistics. The introduction of these definitions is a step, albeit a timid one, towards an increased acceptance of epidemiology in determining the relationships which affect death related to pregnancy. It is to be hoped that the trend thus initiated can be encouraged.