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Year : 2023  |  Volume : 21  |  Issue : 1  |  Page : 37-43

Missing the trees for the forest: A survey of sub-district-level mortality pattern in North Bihar, India

1 Department of Community Medicine, Government Medical College; Department of Community Medicine, Kotagiri Medical Fellowship Hospital, Nilgiris, Tamil Nadu, India
2 Department of Community Medicine, Government Medical College, Nilgiris, Tamil Nadu; Department of Endocrinology, Believers Church Medical College and Hospital, Thiruvalla, Kerala, India
3 Department of Community Medicine, Government Medical College, Nilgiris, Tamil Nadu; Department of General Medicine, ICMDA, New Delhi, India
4 Department of Community Medicine, Government Medical College, Nilgiris, Tamil Nadu; Department of Epidemiology and Research, Duncan Hospital, Raxaul, Bihar, India

Date of Submission20-Aug-2022
Date of Decision10-Oct-2022
Date of Acceptance20-Oct-2022
Date of Web Publication17-Jan-2023

Correspondence Address:
Dr. Sharon Cynthia
Department of Community Medicine, Government Medical College, Nilgiris - 643 001, Tamil Nadu
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/cmi.cmi_92_22

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Background and Objective: The paucity of knowledge on mortality patterns in a state such as Bihar with its population of 200 million contributes to misdirected planning and prioritization of health expenditure. This study aims to estimate the regional differences in mortality rates between a region in North Bihar and the rest of state and country. Methodology: Using a multi-stage cluster design, 4159 households were interviewed across six Community Development blocks in North Bihar, identifying deaths between the Chhath festivals of 2014 and 2015. The cause of death was assessed by verbal autopsy and coded using the International Classification of Disease 10. Proportionate and specific mortality rates were calculated. Results: Of 229 deaths, only 7% were registered. The epidemiological transition level for the region was 1.12 with an infant mortality rate of 72 per 1000 live births (95% confidence interval [CI] 55.7–88.4) and under-five mortality rate of 93.2 per 1000 live births (95% CI 74.6–111.7). These rates were double that of the state estimates. Among infant deaths, infections predominated over prematurity while in adult deaths diseases of the respiratory system exceed diseases of the circulatory system as seen in the state and country mortality rates. Conclusions: This study indicates that regional mortality patterns widely differ from state and national average estimates. Deaths due to maternal and neonatal conditions along with communicable diseases still predominate over other causes. Obtaining disaggregated information on causes of death by strengthening the vital registration system will bring these variations into focus.

Keywords: Epidemiological transition level, life table, mortality, verbal autopsy, vital statistics certification

How to cite this article:
Cynthia S, George MT, Finny P, Thomas MS, Armstrong LJ. Missing the trees for the forest: A survey of sub-district-level mortality pattern in North Bihar, India. Curr Med Issues 2023;21:37-43

How to cite this URL:
Cynthia S, George MT, Finny P, Thomas MS, Armstrong LJ. Missing the trees for the forest: A survey of sub-district-level mortality pattern in North Bihar, India. Curr Med Issues [serial online] 2023 [cited 2023 Jun 7];21:37-43. Available from: https://www.cmijournal.org/text.asp?2023/21/1/37/367867

  Introduction Top

Birth and death vital records have played a crucial role in understanding and improving public health systems.[1],[2] Reliable information regarding cause-specific mortality plays a pivotal role in evidence-based decision-making in public health.[3],[4] The major data sources for estimation of cause of mortality in India include Sample Registration System, vital registration, censuses, and large-scale national household surveys such as the National Family Health Survey and District-Level Household Survey are variable and uncertain.[5]

In 2015, Bihar, the third largest state in India, had the lowest estimated deaths registered (31.9%) with no improvement in the preceding 10 years.[6] A state-wise report on Medical Certification of Cause of Death (MCCD) by the Office of the Registrar General of India is the only available database on cause-specific mortality. However, this report is based on medically certified deaths occurring in public or private hospitals predominantly from urban areas, perpetuating the “scandal of invisibility.”[7] In 2015, 6.6% of registered deaths in Bihar had medically certified cause of death, compared to 22% of registered deaths in India.[8] This trend did not change as only 5.1% of registered deaths had a medically certified cause of death in 2019.[9]

While state-level estimation of various mortality indicators is available and useful,[9] the wide differences in disease burden within the state have gone unnoticed between the confidence limits.[4] This paucity of knowledge on mortality patterns impairs the effectiveness of health planning and prioritization reflected in the decline of Bihar's overall Health Index score as per NITI Aayog in round 1 (2014–2015) and round 4 (2019–2020).[10],[11]

The India State-Level Disease Burden Initiative Collaborators have provided a comprehensive analysis of the state-level variations in the magnitude of deaths, their causes, and risk factors where Bihar is classified in the low epidemiological transition level (ETL) group with a level of 0.74.[4],[9] The term epidemiological transition refers to the shift in cause-of-death patterns that comes with the overall decline of death rates.

The present study is part of another study involving the collection and analysis of cause-of-death data to estimate the incidence of deaths due to snakebites and other causes. The snakebite-related data was published[12] earlier. The data related to other causes of death are presented in this study with the aim to estimate the cause-specific and age-proportionate mortality rates in six Community Development (CD) Blocks of East Champaran district of Bihar on the Indo-Nepal border and determine its differences with the rest of the state and the country. Though this study was done in 2015 and the COVID pandemic had most likely impacted the mortality rates, these findings will contribute to the minimal amount of scientific evidence originating from this region for the given study period.

  Methodology Top

Study design

A cross-sectional survey was conducted after ethical approval from Emmanuel Hospital Association Research and Ethics Committee (Proposal Number 119). Ethics committee approval included the cause of death data collection and analysis.


The survey was done in six out of 27 CD blocks in East Champaran district in the northern part of Bihar. The area is one of the 50 districts in India with the worst health outcomes.[13]

Study period

Data was collected regarding events over 13 months from Chhath in October 2014 to Chhat in November 2015. The region's most important festival was used as a time marker to decrease recall error.


Multi-stage cluster sampling method was used to randomly choose 13 wards from six CD Blocks.[12] A ward is an administrative unit with a population of 2000–3000 persons. All persons belonging to one ward were included and those present in the village for less than a month during the study period were excluded from the study.


Data were collected in two parts-the Household questionnaire to collect demographic information about members of the household and the Verbal Autopsy (VA) form (adapted from the Million Death Study VA form) to investigate the cause of every death in these households.[13],[14]


The primary outcome of this study was the difference in proportionate mortality rate in each age group (<15, 15–39, 40–70, and more than 70 years) between study population and Bihar.[15] Cause-specific mortality rates, demographic indicators, and life expectancy were measured as secondary outcomes. Potential confounders were deaths with an unknown cause which may have led to lower rate estimates.

Data sources

The study questionnaire containing demographic data and cause of death was designed in Hindi. After written consent was obtained from the head of the household, the questionnaire was administered in Bhojpuri by locally trained interviewers. Training was provided to the interviewers on the process of informed consent, household survey and verbal autopsy. After written consent was obtained from the head of the household, the questionnaire was administered in Bhojpuri.

All the VA reports were reviewed independently by two physicians to assign a cause of death and a third physician's opinion was sought when there was a discrepancy. The cause was coded using the International Classification of Diseases version 10 (ICD-10) and also categorized as per the groups of causes mentioned in the Global Burden of Disease report.[9]

Bias and errors

Field verification was conducted to address any issues of bias and errors in tandem with the data collection. This enabled the field interviewers to have ongoing training based on the errors identified. Data were verified for 1585 persons in 188 households and 382 errors were identified. A majority (78%) of which were about the residence status (whether or not permanently residing in the village and about the duration of stay if temporarily present). Others were persons erroneously included or excluded from the study. There were nine missed deaths and six deaths outside the study period.

Study size

This study population was expected to have 240 deaths based on crude death rate of 7.3 per 1000 population. A sample size of 225 deaths was calculated to assess the difference between two proportionate mortality rates among children <1 year (19.6% in Bihar[8] and estimated 31% among those in the study area) with 95% confidence limits and 80% power.

Statistical methods

Data were entered and analyzed using Epi Info Version 7 by Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia (US). Categorical variables were expressed in rates, ratios, and proportions with 95% confidence limits. Cause-specific mortality rate was calculated by dividing the number of deaths in each ICD 10 category by the total number of deaths. Proportionate mortality rate was calculated by dividing the number of deaths in each category according to GBD by the total population. Life table analysis was done using Microsoft Excel with the formulae given in Measure evaluation, USAID, North Carolina.[16]

  Results Top

A total of 34,814 persons were interviewed in 4159 households belonging to 13 villages. An average of 85.2% of the villagers were interviewed. Their age and sex distribution is given in [Figure 1]. The average household size was 8.4 with a range of up to 38. There were 1042 births, 229 deaths, and 25 stillbirths in the study sample which gives a crude birth rate of 29.9 per 1000 population (95% confidence interval [CI] 28.1–31.7), a crude death rate of 7.3 per 1000 population (95% CI 5.7–7.4) and general fertility rate of 127.6 births per 1000 women in reproductive age group (95% CI 119.9–135.4).[17] The life table estimates the life expectancy at birth to be 68 years for this region.
Figure 1: Population pyramid of East Champaran.

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These indicators along with other demographic indicators for this region have been compared with that of Bihar and India for the same time period in [Table 1].
Table 1: Vital statistics for East Champaran district study sample endometrial cancer Bihar state and country India[19]

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Of the 229 deaths over 1 year, 51.9% of deaths were males and one in five deaths (20.1%) occurred in a health facility. The majority of deaths occurred at home (57.4%). Death certification in the study area was 7%. The five leading causes of death according to verbal autopsies were conditions originating in the perinatal period, diseases of the respiratory system, infections and parasitic diseases, diseases of the circulatory system, and injuries and external causes. The cause-specific mortality rates are listed in [Table 2]. Conditions originating in the perinatal period were the highest cause of death followed by diseases of the respiratory system and infections.
Table 2: Cause-specific mortality rate

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Nearly half the deaths (44%, 101) were in the under-five age group, the details of which are given in [Table 3]. A hundred and one babies under the age of five died in this region in 1 year. Of these, half died in the 1st month of life, and nearly one in five died in the first 48 h after birth. Almost two-thirds died at home and one in four was reported as never being seen by any health-care provider. No report was made of receiving any home-based care by an Anganwadi worker, accredited social health activist (ASHA), or auxiliary nurse midwife (ANM).
Table 3: Death rates for the under-five age categories for East Champaran study population, state, and country

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The ETL was 1.12, with 52.7% (121, 95% CI 46.15–59.45) deaths due to Communicable, maternal, neonatal, and nutritional diseases (CMNNDs), 38.86% (89, 95% CI 32.51–45.51) due to noncommunicable diseases (NCDs), 6.11% (14, 95% CI 3.38–10.04) due to injuries, and 2.8% (5, 95% CI 0.71–5.02) was unknown.

Among all deaths, the highest proportion was 47.6% (109) between 0 and 14 years mostly due to CMNNDs and the lowest was 11.4% (26) between 15 and 39 years [Figure 2]. In [Figure 3], there is a comparison of the causes of death in East Champaran (inner ring) as compared to the low ETL regions including the state of Bihar (outer ring).
Figure 2: Proportion of deaths by ETL categories. ETL: Epidemiological transition level.

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  Discussion Top

The study results brought to attention, the sub-district-level cause-specific mortality data. The top three causes of death in East Champaran were maternal and neonatal disorders, respiratory infections, and tuberculosis (TB) followed by cardiovascular diseases. This situation was very different from low ETL regions where the top three causes were NCDs namely cardiovascular diseases, neoplasms, and chronic respiratory diseases. The study population's ETL was 1.12 compared to 0.74 for the state in 2016.[4],[9] In India, including Bihar as a whole, NCDs and injuries had become the predominant cause of death in 2003. But even after 12 years in 2015, the deaths due to CMMNDs were still way ahead of NCDs in the study population of East Champaran (EC).

The population pyramid for the region resembled that of India 50 years ago and the general fertility rate was close to double the national figure for the corresponding period. This was reflected in the broad base [Figure 1] influenced by socio economic factors like young age of marriage, illiteracy, and lack of formal employment among women which were prevalent in this region.[18] The life expectancy at birth was 68.2 and comparable to the WHO model life table system with state-specific inputs.[5]

The proportionate mortality rate in each age group in the study population was compared with that of Bihar to estimate the extent of intra-state variations [Figure 3].
Figure 3: Comparison of proportionate mortality between EC and Bihar.[4] EC: East Champaran ETL: Epidemiological transition level.

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The age group 0–14 years contributed to 47.6% in the EC study population compared to 18.6% of total deaths in Bihar. Even though an analysis of MCCD data for 2002–2014 in urban Bihar revealed a declining rate of deaths in this age group, a Niti Aayog report of Bihar reported an increase in neonatal, infant, and under-five mortality during the study period. While the state's performance showed an overall decline, the rates were far worse at a sub district level.[8],[19]The predominant factors associated with under-five mortality in this region were infections (42%) within the first 2 days of life (22%) without any health care (34%) and death occurring at home (63%) [Figure 4]. In depth interviews conducted among nurses have identified logistical (lack of supply of emergency drugs and basic equipment, distance between labor room and resuscitation area), cultural (early administration of oxytocin and delayed presentation of mothers in labor) and structural barriers (poverty, traditional clinical practices, and hierarchy) to evidence based neonatal care in Bihar.[20]
Figure 4: Sankey chart of factors associated with under five deaths in EC. EC: East Champaran.

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In the 15–39-year age group the top three causes of death in the EC study population were, unintentional injuries in migrant laborers (19.2%), maternal deaths (15.3%), and acute abdominal conditions requiring surgery (19.2%); whereas for the state they were Neglected Tropical Diseases and malaria (13.4%), chronic respiratory diseases (12.8%), HIV and TB (11.8%).[4] There is no evidence in scientific literature on the mortality among Bihari migrant workers due to injuries. Specific death rate of injuries and poisonings was ten times higher in the study population as compared to rural Gadchiroli in Maharashtra[21] [Table 2].

Of the verbal autopsies on the four maternal deaths, there was no mention of care given by ASHA or ANM or access to ambulance services or death registration. Half of these deaths were in teenagers reflecting the reported risk of maternal death being highest in the 13–19 year age group with an odds ratio of 3.66.[22] The teenagers were in their second trimester with features suggestive of urinary tract infection and infective gastroenteritis. Both died at home after improper management by private hospitals and local quacks over a period of 15 days to 1 month. The other two deaths were due to postpartum hemorrhage (PPH)-one on the way from a government PHC to a private hospital with no blood transfusion and no ambulance services, and the other due to secondary PPH with sepsis following a cesarean section in a private hospital.

These deaths bring to light the extent of child marriage and the lack of basic and emergency antenatal and postnatal care[9] still existing in pockets of Bihar. In a review of nine EAG states in India, inappropriate quality of care at the health facility has been the cause of maternal mortality most frequently cited.[22] The National Health Mission has been instrumental in bringing down maternal mortality in India and Bihar. However, lack of knowledge about deaths in areas such as EC will hinder further progress.

Among those aged 40–69 years, and 70 years and above, the burden of respiratory infections including TB and chronic respiratory disease was much higher than the state average (23.8 vs. 2.5 and 21.4 vs. 16.4). The TB Specific mortality rate of 54.6 in EC was higher than in rural Gadchiroli (51.5) and was attributed to a delay in diagnosis.[21] Care was sought from a minimum of three healthcare providers before a diagnosis was made, according to the VA reports. The reasons for delay in diagnosing TB are the lack of access to tests and lack of identification of high-risk cases because the diagnostic algorithm was not followed.[23]

Among NCDs, cardiovascular diseases and diabetes are emerging as the major causes of mortality in other low ETL regions within India.[4] This was different in the study population as diseases of the respiratory system were the highest among NCDs causing mortality (Specific mortality rate: 112 (95% CI 76.9–147.2) which is double the rate of rural Gadchiroli (54.2). The reason may be attributed to the indoor air pollution due to usage of solid cooking fuel like cow dung and coal. The ratio of households using solid cooking fuel like wood, cow dung, coal, or kerosene to those using liquid petroleum gas, biogas, or electricity is 2 for the country, 11 for Bihar, and 17 for the East Champaran district.[24],[25]

Four deaths due to communicable diseases warrant special attention: A 4-year-old who died of measles complicated by pneumonia, a 3-year-old who developed tetanus following a chronic ear infection, a 15-year-old who died of Kala Azar, and a 30-year-old who died of cholera in an outbreak following the Nepal earthquake. The State Health Society of Bihar's report on the Integrated Disease Surveillance Program (IDSP) which monitors the trend in communicable diseases, showed an increase in measles incidence in 2015 and 2016 compared to previous years. In 2016 alone, 78 outbreaks of measles were reported from 22 districts resulting in 8 deaths. However, the IDSP report had no presumptive or laboratory surveillance data of measles or tetanus or Kala Azar from East Champaran district.[26] The four deaths mentioned above and several more cases remained hidden and unreported, thereby highlighting the need for regional-level mortality data.

Therefore, it is evident that in each age group and in each category of diseases there are major differences between the patterns of mortality in the six CD blocks of East Champaran district and of Bihar as a whole.

A limitation of the study was that the data collectors were all male and they may have missed recording some neonatal deaths which were mostly reported only by the mothers.

  Conclusions Top

Within Bihar, there are regions with mortality patterns which vastly differ from the state and the country average estimates. In a region where death data is limited, verbal autopsies are an important tool to collect this data. This information is essential to identify priorities and allocate resources to design, monitor, and evaluate healthcare interventions.

Ethical statement

Ethical committee approval was obtained from Emmanuel Hospital Association Research and Ethics Committee (Proposal Number 119).

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

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  [Figure 1], [Figure 2], [Figure 3], [Figure 4]

  [Table 1], [Table 2], [Table 3]


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