Neonatal mortality is the death of a live-born baby within the first 28 days of birth. For the se... more Neonatal mortality is the death of a live-born baby within the first 28 days of birth. For the selected households, neonatal mortality was collected from children aged 0–28 days and women aged 15–49. The neonatal period is a significant 4-week period in human life because it carries a greater mortality risk. To identify the determinant factors of neonatal mortality in Ethiopia based on EDHS 2016 data with the application of count regression models. In this study, all neonates in Ethiopia were born within the 5 years preceding EDHS 2016 of the source population in the selected EAs from September to December 2015. Count regression models were used to analyze the data. A total of 10,641 live-born neonates within the previous 5 years of EDHS 2016 had neonatal mortality of women aged 15–49, which was considered in the study to be 7193. The data were found to have excess zeros (96.6%), and the variance (0.052) was higher than its mean (0.04). The count regression model (ZINB) was best fit...
Student attrition is a challenge for higher education institutions across the world. The purpose ... more Student attrition is a challenge for higher education institutions across the world. The purpose of this study was to examine the application of joint model using students' commutative grade point average and attrition status. A total of 258 college student samples were used in this study. A mixed effect model for students' grade point average and a Cox hazard model for students' attrition status were modeled independently, and both submodels were modeled jointly by linking random effects through a shared parameter model. This study focused on gender issues, academic background, peer support, and residence. From the finding of this study, 26.4% were attrition, and 73.6% were retained. The estimated trend of commutative grade point average was found to be negatively associated with attrition status. The major factors that encounter students' attritions were academic background and institutional factors.
Background Currently, about 165 million children are categorized under malnutrition and 51.5 mill... more Background Currently, about 165 million children are categorized under malnutrition and 51.5 million suffering from acute malnutrition in world wide. Hence, the objective of current study was to assess the recovery time and its predictors of children under five from severe acute malnutrition admitted to Therapeutic Feeding Unit at Dubti Referral Hospital, Afar region, Eastern Ethiopia. Methods Institutional based retrospective cohort study was conducted on 650 inpatient children with SAM admitted for therapeutic feeding unit whose treatment was from March to April/2017. Results The result in current investigation indicates that the average recovery time from SAM was found to be 21 days (95% CI; 21.23–25.77), p-value = 0.035). A Cox proportional hazard regression model revealed that Weight of a child at birth, gestational age of a child, working status of a child at admission birth order of a child, mother’s BMI, mother’s level of education, mother’s stature, mother’s occupation, mot...
Background : Glaucoma is a neurodegenerative condition that affects the eye and is associated wit... more Background : Glaucoma is a neurodegenerative condition that affects the eye and is associated with increased intraocular pressure. Intraocular pressure is the fluid pressure inside the eye and its disturbance often is implicated in the development of pathologies such as glaucoma, uveitis and retinal detachment. The aim of the present study was to identify factors that affect the longitudinal intraocular pressure of glaucoma patients attending the ophthalmology clinic at Felege Hiwot Comprehensive Specialized Hospital, Bahir Dar, Ethiopia, using a Bayesian linear mixed model analysis. Methods: In a longitudinal study with data obtained from glaucoma patients admitted to Felege Hiwot Hospital, the measurement of intraocular pressure change was applied. The study subjects were enrolled in the period between 1 st January 2016 and 1 st January 2020 and a total of 328 patients were selected for the study. Data were explored using descriptive statistics and individual and mean profile plots throughout study time. A Bayesian linear mixed model for the longitudinal data was used along with their model comparison, model estimation, model diagnosis and missing data analysis. Results: The analysis included 328 individuals with 9 for maximum and 2 for minimum repeated measurements of intraocular pressure change, including the baseline. From the Bayesian linear mixed model variables, observation time, age, place of residence, gender, the cup-disk ratio of patients, type of medication (like Pilocarpin, Timolol with Pilocarpin, Timolol with Diamox with Pilocarpin), and blood pressure of the glaucoma patients significantly affected the intraocular pressure changes over time. However, the type of medication (Diamox and Timolol with Diamox) did not affect the intraocular pressure changes over time. Conclusion: Based on the Bayesian linear mixed model analysis, we found that the predictor variables of age, blood pressure, family history, residence, gender, diabetic disease, treatment duration, stages of glaucoma, type of medication and cup-disk ratio significantly affected the average intraocular pressure and had a positive association with the responses of intraocular pressure of glaucoma patients. Furthermore, the type of medication was statistically significant and negatively associated with the responses to intraocular pressure. Recommendation: We recommend the health professionals to give more attention to the type of medication especially Timolol with Pilocarpin, Timolol with Diamox and Timolol with Diamox with Pilocarpine. And taking the combination with the other type of medication minimizes the risk of blindness and intraocular pressure.
Additional file 1. Questionnaire developed to assess house characteristics of study participants.... more Additional file 1. Questionnaire developed to assess house characteristics of study participants. Questionnaire developed to assess characteristics of the household members.
This paper studies the effect of mosquito abundance and malaria incidence in the last 3 weeks, an... more This paper studies the effect of mosquito abundance and malaria incidence in the last 3 weeks, and their interaction, on the hazard of time to malaria in a previously studied cohort of children in Ethiopia. We model the mosquito abundance and time to malaria data jointly in a Bayesian framework. We found that the interaction of mosquito abundance and incidence plays a prominent role on malaria risk. We quantify and compare relative risks of various factors, and determine the predominant role of the interaction between incidence and mosquito abundance in describing malaria risk. Seasonal rain patterns, distance to a water source of the households, temperature and relative humidity are all significant in explaining mosquito abundance, and through this affect malaria risk. Analyzing jointly the time to malaria data and the mosquito abundance allows a precise comparison of factors affecting the spread of malaria. The effect of the interaction between mosquito abundances and local presen...
Background: Leukemia is a type of cancers that start in the bone marrow and produce a serious num... more Background: Leukemia is a type of cancers that start in the bone marrow and produce a serious number of abnormal white blood cells. Bleeding and bruising problems, fatigue, fever, and an increased risk of infection are among symptoms of the disease. The main objective of this study is to identify the determinant of the progression rate of white blood cells among patients with chronic lymphocytic leukemia at Felege Hiwot Referral Hospital (FHRH), Bahir Dar, Ethiopia. Methods: A retrospective study design was conducted on 312 patients with chronic lymphocytic leukemia at FHRH, Bahir Dar, Ethiopia under treatment from 1 January 2017 to 31 December 2019. A linear mixed-effects model was considered for the progression of the white blood cell data. Results: The estimated coefficient of the fixed effect intercept was 84.68, indicating that the average white blood cell (WBC) count of the patients was 84.68 at baseline time by excluding all covariates in the model ( P-value
In this work we present a spatial approach to model and investigate mortality data referenced ove... more In this work we present a spatial approach to model and investigate mortality data referenced over a Lexis structure. We decompose the force of mortality into two interpretable components: a Markov random field, smooth with respect to time, age and cohort which explains the main pattern of mortality; and a secondary component of independent shocks, accounting for additional non-smooth mortality. Inference is based on a hierarchical Bayesian approach with Markov chain Monte Carlo computations. We present an extensive application to data from the Human Mortality Database about 37 countries. For each country the primary smooth surface and the secondary surface of additional mortality are estimated. The importance of each component is evaluated by the estimated value of the respective precision parameter. For several countries we discovered a band of extra mortality in the secondary surface across the time domain, in the age interval between 60 and 90 years, with a slightly positive slo...
Background. Heart failure is a progressive condition marked by worsening symptoms such as shortne... more Background. Heart failure is a progressive condition marked by worsening symptoms such as shortness of breath, coughing, exhaustion and lethargy, fluid retention with swelling of the legs and abdomen, and a reduced ability to exercise. As a result, this study aims to use a joint model application to determine the joint risk factors of longitudinal change in pulse rate and time to death of congestive heart failure patients and their association admitted to a hospital. Methods. A retrospective study was undertaken on congestive heart failure patients admitted to the Debre Tabor Referral Hospital from January 2016 to December 2019. A statistical joint modeling strategy was employed to match the repeated biomarker pulse rate and a survival outcome at the same time. A total of 271 patients with congestive heart failure were chosen. Data were analyzed with R statistical software via joineRML. Results. According to the findings, the association between longitudinal changes in pulse rate an...
Background Understanding the behaviour of local malaria vectors is essential as effectiveness of ... more Background Understanding the behaviour of local malaria vectors is essential as effectiveness of the commonly used vector-targeted malaria control tools heavily relies on behaviour of the major malaria vectors. This study was conducted to determine species composition, biting behaviour, host preference and infectivity of anopheline mosquitoes, and assess utilization of insecticide-treated nets (ITNs) in a low transmission setting in Southwest Ethiopia. Methods Adult anopheline mosquitoes were collected using human landing catches (HLCs), Centers for Disease Control and Prevention (CDC) light traps (LTs) and Pyrethrum Spray Catches (PSCs) from June 2016 to May 2018 in Kishe, Jimma Zone, Southwest Ethiopia. The anopheline mosquitoes were morphologically identified. Moreover, sub-sample of An. gambiae s.l. was identified to species using polymerase chain reaction (PCR). Circum-sporozoite proteins (CSPs) and blood meal sources of the anopheline mosquitoes were tested using enzyme-linked...
Perinatal mortality is the death of a fetus after the age of viability until the 7 day of life. P... more Perinatal mortality is the death of a fetus after the age of viability until the 7 day of life. Perinatal mortality is estimated by the addition of stillbirths plus the early neonatal mortality, which represents deaths occurring during the first 7 days after delivery. Perinatal mortality remains a great burden in Ethiopia. The purpose of this study was to assess and compare the demographic and socio-economic determinant factors of perinatal mortality in Ethiopia using the 2011 and 2016 Ethiopian Demographic Health Surveys (EDHS). For data analysis, the Bayesian multilevel Model was used in this study. The study revealed that there is a regional variation in perinatal mortality and this variation was high in 2011 EDHS than in 2016 EDHS data. Factors like sex of the child, age of mother, wealth index, family size, birth order, source of drinking water, place of residence, place of delivery, and child twin were found to be the determinant factors of perinatal mortality in both 2011 and...
Background Both short and long birth intervals are associated with many risk factors and about 29... more Background Both short and long birth intervals are associated with many risk factors and about 29% of births are short birth intervals in Ethiopia. The purpose of this study is to model the birth intervals of adult women aged 15–49 years using accelerated failure time and shared frailty models in order to analyze the birth intervals of Ethiopian women. Methods The data was obtained from the 2016 Ethiopian Demographic and Health Survey (EDHS). Accelerated failure time with different baseline and shared frailty models are used for the analysis to identify important demographic and socio-economic factors affecting the length of birth intervals and correlates of the birth intervals respectively. Results The data consists of 9147 women, of which about 7842 (85.5%) are closed interval and the rest of 1323(14.5%) are open interval. Accelerated failure time (AFT) result revealed that women education level, husbands education level, age at first birth, marital status, religion and family wea...
Background: Malnutrition is associated with both under nutrition and over nutrition which causes ... more Background: Malnutrition is associated with both under nutrition and over nutrition which causes the body to get improp- er amount of nutrients to maintain tissues and organ function. Under nutrition is the result of insufficient intake of food, poor utilization of nutrients due to illnesses, or a combination of these factors. The purpose of this study was to identify associated risk factors and assess the variation of underweight among under-five children of different regions in Ethiopia. Methods: Ethiopian Demography and Health Survey (EDHS-2016) weight-to-age data for under-five children is used. In order to achieve the objective of this study; descriptive, single level and multilevel ordinal logistic regression analysis were used. Results: From a total of 8935 children about 8.1% were severely underweight, 17.1% were moderately underweight and 74.8% were normal. The test of heterogeneity suggested that underweight varies among region and multilevel ordinal model fit data better ...
Background: Personalised or stratified medicine has played an increasingly important role in impr... more Background: Personalised or stratified medicine has played an increasingly important role in improving bio-medical care in recent years. A Bayesian joint modelling approach to dynamic prediction of HIV progression and mortality allows such individualised predictions to be made for HIV patients, based on monitoring of their CD4 counts. This study aims to provide predictions of patient-specific trajectories of HIV disease progression and survival.Methods: Longitudinal data on 254 HIV/AIDS patients who received ART between 2009 and 2014, and who had at least one CD4 count observed, were employed in a Bayesian joint model of disease progression, as measured by CD4 counts, and survival, to obtain individualised dynamic predictions of both processes that were updated at each visit time in the follow-up period. Different forms of association structure that relate the longitudinal CD4 biomarker and time to death were assessed; and predictions were averaged over the different models using Ba...
Background: Dental caries are a significant public health problem. It is a disease with multifact... more Background: Dental caries are a significant public health problem. It is a disease with multifactorial causes. In Sub-Sahara Africa, Ethiopia is one of the countries with a high record of dental caries. This study was to determine the risk factors affecting dental caries using both Bayesian and classical approaches. Methods: The study design was a retrospective cohort study in the period of March 2009 to March 2013 dental caries patients Hawassa Haik Poly Higher Clinic. The Bayesian logistic regression procedure was adapted to make inference about the parameters of a logistic regression model. The purpose of this method was generating the posterior distribution of the unknown parameters given both the data and some prior density for the unknown parameters. Results: From this study the prevalence of natural dental caries was 87% and non-natural dental caries were 13%. The age group of 18-25 was higher prevalence of dental caries than the other age groups. From Bayesian logistic regression, we found out that rural patients, do not clean their teeth, patients from SNNPR and age group 18-25 are statistically significant. The finding from the Bayesian statistics approach is getting popular in data analysis than classical statistics because the technique is more robust and precise. Conclusions: Bayesian approach was found to be better than classical method as the value of the standard errors in Bayesian approaches is smaller than that of classical logistic regression. The Bayesian credible interval is smaller than the length of the confidence interval for all significant risk factors. Age, sex, place of residence, region and habit of cleaning teeth was found to have a significant effect on dental caries patients.
Background: Dental caries are a significant public health problem. It is a disease with multifact... more Background: Dental caries are a significant public health problem. It is a disease with multifactorial causes. In Sub-Sahara Africa, Ethiopia is one of the countries with a high record of dental caries. This study was to determine the risk factors affecting dental caries using both Bayesian and classical approaches. Methods: The study design was a retrospective cohort study in the period of March 2009 to March 2013 dental caries patients Hawassa Haik Poly Higher Clinic. The Bayesian logistic regression procedure was adapted to make inference about the parameters of a logistic regression model. The purpose of this method was generating the posterior distribution of the unknown parameters given both the data and some prior density for the unknown parameters. Results: From this study the prevalence of natural dental caries was 87% and non-natural dental caries were 13%. The age group of 18-25 was higher prevalence of dental caries than the other age groups. From Bayesian logistic regression, we found out that rural patients, do not clean their teeth, patients from SNNPR and age group 18-25 are statistically significant. The finding from the Bayesian statistics approach is getting popular in data analysis than classical statistics because the technique is more robust and precise. Conclusions: Bayesian approach was found to be better than classical method as the value of the standard errors in Bayesian approaches is smaller than that of classical logistic regression. The Bayesian credible interval is smaller than the length of the confidence interval for all significant risk factors. Age, sex, place of residence, region and habit of cleaning teeth was found to have a significant effect on dental caries patients.
Background: This paper studies the effect of mosquito abundance and malaria incidence in the last... more Background: This paper studies the effect of mosquito abundance and malaria incidence in the last 3 weeks, and their interaction, on the hazard of time to malaria in a previously studied cohort of children in Ethiopia. Methods: We model the mosquito abundance and time to malaria data jointly in a Bayesian framework. Results: We found that the interaction of mosquito abundance and incidence plays a prominent role on malaria risk. We quantify and compare relative risks of various factors, and determine the predominant role of the interaction between incidence and mosquito abundance in describing malaria risk. Seasonal rain patterns, distance to a water source of the households, temperature and relative humidity are all significant in explaining mosquito abundance, and through this affect malaria risk. Conclusion: Analyzing jointly the time to malaria data and the mosquito abundance allows a precise comparison of factors affecting the spread of malaria. The effect of the interaction between mosquito abundances and local presence of malaria parasites has an important effect on the hazard of time to malaria, beyond abundance alone. Each additional one km away from the dam gives an average reduction of malaria relative risk of 5.7%. The importance of the interaction between abundance and incidence leads to the hypothesis that preventive intervention could advantageously target the infectious population, in addition to mosquito control, which is the typical intervention today.
Neonatal mortality is the death of a live-born baby within the first 28 days of birth. For the se... more Neonatal mortality is the death of a live-born baby within the first 28 days of birth. For the selected households, neonatal mortality was collected from children aged 0–28 days and women aged 15–49. The neonatal period is a significant 4-week period in human life because it carries a greater mortality risk. To identify the determinant factors of neonatal mortality in Ethiopia based on EDHS 2016 data with the application of count regression models. In this study, all neonates in Ethiopia were born within the 5 years preceding EDHS 2016 of the source population in the selected EAs from September to December 2015. Count regression models were used to analyze the data. A total of 10,641 live-born neonates within the previous 5 years of EDHS 2016 had neonatal mortality of women aged 15–49, which was considered in the study to be 7193. The data were found to have excess zeros (96.6%), and the variance (0.052) was higher than its mean (0.04). The count regression model (ZINB) was best fit...
Student attrition is a challenge for higher education institutions across the world. The purpose ... more Student attrition is a challenge for higher education institutions across the world. The purpose of this study was to examine the application of joint model using students' commutative grade point average and attrition status. A total of 258 college student samples were used in this study. A mixed effect model for students' grade point average and a Cox hazard model for students' attrition status were modeled independently, and both submodels were modeled jointly by linking random effects through a shared parameter model. This study focused on gender issues, academic background, peer support, and residence. From the finding of this study, 26.4% were attrition, and 73.6% were retained. The estimated trend of commutative grade point average was found to be negatively associated with attrition status. The major factors that encounter students' attritions were academic background and institutional factors.
Background Currently, about 165 million children are categorized under malnutrition and 51.5 mill... more Background Currently, about 165 million children are categorized under malnutrition and 51.5 million suffering from acute malnutrition in world wide. Hence, the objective of current study was to assess the recovery time and its predictors of children under five from severe acute malnutrition admitted to Therapeutic Feeding Unit at Dubti Referral Hospital, Afar region, Eastern Ethiopia. Methods Institutional based retrospective cohort study was conducted on 650 inpatient children with SAM admitted for therapeutic feeding unit whose treatment was from March to April/2017. Results The result in current investigation indicates that the average recovery time from SAM was found to be 21 days (95% CI; 21.23–25.77), p-value = 0.035). A Cox proportional hazard regression model revealed that Weight of a child at birth, gestational age of a child, working status of a child at admission birth order of a child, mother’s BMI, mother’s level of education, mother’s stature, mother’s occupation, mot...
Background : Glaucoma is a neurodegenerative condition that affects the eye and is associated wit... more Background : Glaucoma is a neurodegenerative condition that affects the eye and is associated with increased intraocular pressure. Intraocular pressure is the fluid pressure inside the eye and its disturbance often is implicated in the development of pathologies such as glaucoma, uveitis and retinal detachment. The aim of the present study was to identify factors that affect the longitudinal intraocular pressure of glaucoma patients attending the ophthalmology clinic at Felege Hiwot Comprehensive Specialized Hospital, Bahir Dar, Ethiopia, using a Bayesian linear mixed model analysis. Methods: In a longitudinal study with data obtained from glaucoma patients admitted to Felege Hiwot Hospital, the measurement of intraocular pressure change was applied. The study subjects were enrolled in the period between 1 st January 2016 and 1 st January 2020 and a total of 328 patients were selected for the study. Data were explored using descriptive statistics and individual and mean profile plots throughout study time. A Bayesian linear mixed model for the longitudinal data was used along with their model comparison, model estimation, model diagnosis and missing data analysis. Results: The analysis included 328 individuals with 9 for maximum and 2 for minimum repeated measurements of intraocular pressure change, including the baseline. From the Bayesian linear mixed model variables, observation time, age, place of residence, gender, the cup-disk ratio of patients, type of medication (like Pilocarpin, Timolol with Pilocarpin, Timolol with Diamox with Pilocarpin), and blood pressure of the glaucoma patients significantly affected the intraocular pressure changes over time. However, the type of medication (Diamox and Timolol with Diamox) did not affect the intraocular pressure changes over time. Conclusion: Based on the Bayesian linear mixed model analysis, we found that the predictor variables of age, blood pressure, family history, residence, gender, diabetic disease, treatment duration, stages of glaucoma, type of medication and cup-disk ratio significantly affected the average intraocular pressure and had a positive association with the responses of intraocular pressure of glaucoma patients. Furthermore, the type of medication was statistically significant and negatively associated with the responses to intraocular pressure. Recommendation: We recommend the health professionals to give more attention to the type of medication especially Timolol with Pilocarpin, Timolol with Diamox and Timolol with Diamox with Pilocarpine. And taking the combination with the other type of medication minimizes the risk of blindness and intraocular pressure.
Additional file 1. Questionnaire developed to assess house characteristics of study participants.... more Additional file 1. Questionnaire developed to assess house characteristics of study participants. Questionnaire developed to assess characteristics of the household members.
This paper studies the effect of mosquito abundance and malaria incidence in the last 3 weeks, an... more This paper studies the effect of mosquito abundance and malaria incidence in the last 3 weeks, and their interaction, on the hazard of time to malaria in a previously studied cohort of children in Ethiopia. We model the mosquito abundance and time to malaria data jointly in a Bayesian framework. We found that the interaction of mosquito abundance and incidence plays a prominent role on malaria risk. We quantify and compare relative risks of various factors, and determine the predominant role of the interaction between incidence and mosquito abundance in describing malaria risk. Seasonal rain patterns, distance to a water source of the households, temperature and relative humidity are all significant in explaining mosquito abundance, and through this affect malaria risk. Analyzing jointly the time to malaria data and the mosquito abundance allows a precise comparison of factors affecting the spread of malaria. The effect of the interaction between mosquito abundances and local presen...
Background: Leukemia is a type of cancers that start in the bone marrow and produce a serious num... more Background: Leukemia is a type of cancers that start in the bone marrow and produce a serious number of abnormal white blood cells. Bleeding and bruising problems, fatigue, fever, and an increased risk of infection are among symptoms of the disease. The main objective of this study is to identify the determinant of the progression rate of white blood cells among patients with chronic lymphocytic leukemia at Felege Hiwot Referral Hospital (FHRH), Bahir Dar, Ethiopia. Methods: A retrospective study design was conducted on 312 patients with chronic lymphocytic leukemia at FHRH, Bahir Dar, Ethiopia under treatment from 1 January 2017 to 31 December 2019. A linear mixed-effects model was considered for the progression of the white blood cell data. Results: The estimated coefficient of the fixed effect intercept was 84.68, indicating that the average white blood cell (WBC) count of the patients was 84.68 at baseline time by excluding all covariates in the model ( P-value
In this work we present a spatial approach to model and investigate mortality data referenced ove... more In this work we present a spatial approach to model and investigate mortality data referenced over a Lexis structure. We decompose the force of mortality into two interpretable components: a Markov random field, smooth with respect to time, age and cohort which explains the main pattern of mortality; and a secondary component of independent shocks, accounting for additional non-smooth mortality. Inference is based on a hierarchical Bayesian approach with Markov chain Monte Carlo computations. We present an extensive application to data from the Human Mortality Database about 37 countries. For each country the primary smooth surface and the secondary surface of additional mortality are estimated. The importance of each component is evaluated by the estimated value of the respective precision parameter. For several countries we discovered a band of extra mortality in the secondary surface across the time domain, in the age interval between 60 and 90 years, with a slightly positive slo...
Background. Heart failure is a progressive condition marked by worsening symptoms such as shortne... more Background. Heart failure is a progressive condition marked by worsening symptoms such as shortness of breath, coughing, exhaustion and lethargy, fluid retention with swelling of the legs and abdomen, and a reduced ability to exercise. As a result, this study aims to use a joint model application to determine the joint risk factors of longitudinal change in pulse rate and time to death of congestive heart failure patients and their association admitted to a hospital. Methods. A retrospective study was undertaken on congestive heart failure patients admitted to the Debre Tabor Referral Hospital from January 2016 to December 2019. A statistical joint modeling strategy was employed to match the repeated biomarker pulse rate and a survival outcome at the same time. A total of 271 patients with congestive heart failure were chosen. Data were analyzed with R statistical software via joineRML. Results. According to the findings, the association between longitudinal changes in pulse rate an...
Background Understanding the behaviour of local malaria vectors is essential as effectiveness of ... more Background Understanding the behaviour of local malaria vectors is essential as effectiveness of the commonly used vector-targeted malaria control tools heavily relies on behaviour of the major malaria vectors. This study was conducted to determine species composition, biting behaviour, host preference and infectivity of anopheline mosquitoes, and assess utilization of insecticide-treated nets (ITNs) in a low transmission setting in Southwest Ethiopia. Methods Adult anopheline mosquitoes were collected using human landing catches (HLCs), Centers for Disease Control and Prevention (CDC) light traps (LTs) and Pyrethrum Spray Catches (PSCs) from June 2016 to May 2018 in Kishe, Jimma Zone, Southwest Ethiopia. The anopheline mosquitoes were morphologically identified. Moreover, sub-sample of An. gambiae s.l. was identified to species using polymerase chain reaction (PCR). Circum-sporozoite proteins (CSPs) and blood meal sources of the anopheline mosquitoes were tested using enzyme-linked...
Perinatal mortality is the death of a fetus after the age of viability until the 7 day of life. P... more Perinatal mortality is the death of a fetus after the age of viability until the 7 day of life. Perinatal mortality is estimated by the addition of stillbirths plus the early neonatal mortality, which represents deaths occurring during the first 7 days after delivery. Perinatal mortality remains a great burden in Ethiopia. The purpose of this study was to assess and compare the demographic and socio-economic determinant factors of perinatal mortality in Ethiopia using the 2011 and 2016 Ethiopian Demographic Health Surveys (EDHS). For data analysis, the Bayesian multilevel Model was used in this study. The study revealed that there is a regional variation in perinatal mortality and this variation was high in 2011 EDHS than in 2016 EDHS data. Factors like sex of the child, age of mother, wealth index, family size, birth order, source of drinking water, place of residence, place of delivery, and child twin were found to be the determinant factors of perinatal mortality in both 2011 and...
Background Both short and long birth intervals are associated with many risk factors and about 29... more Background Both short and long birth intervals are associated with many risk factors and about 29% of births are short birth intervals in Ethiopia. The purpose of this study is to model the birth intervals of adult women aged 15–49 years using accelerated failure time and shared frailty models in order to analyze the birth intervals of Ethiopian women. Methods The data was obtained from the 2016 Ethiopian Demographic and Health Survey (EDHS). Accelerated failure time with different baseline and shared frailty models are used for the analysis to identify important demographic and socio-economic factors affecting the length of birth intervals and correlates of the birth intervals respectively. Results The data consists of 9147 women, of which about 7842 (85.5%) are closed interval and the rest of 1323(14.5%) are open interval. Accelerated failure time (AFT) result revealed that women education level, husbands education level, age at first birth, marital status, religion and family wea...
Background: Malnutrition is associated with both under nutrition and over nutrition which causes ... more Background: Malnutrition is associated with both under nutrition and over nutrition which causes the body to get improp- er amount of nutrients to maintain tissues and organ function. Under nutrition is the result of insufficient intake of food, poor utilization of nutrients due to illnesses, or a combination of these factors. The purpose of this study was to identify associated risk factors and assess the variation of underweight among under-five children of different regions in Ethiopia. Methods: Ethiopian Demography and Health Survey (EDHS-2016) weight-to-age data for under-five children is used. In order to achieve the objective of this study; descriptive, single level and multilevel ordinal logistic regression analysis were used. Results: From a total of 8935 children about 8.1% were severely underweight, 17.1% were moderately underweight and 74.8% were normal. The test of heterogeneity suggested that underweight varies among region and multilevel ordinal model fit data better ...
Background: Personalised or stratified medicine has played an increasingly important role in impr... more Background: Personalised or stratified medicine has played an increasingly important role in improving bio-medical care in recent years. A Bayesian joint modelling approach to dynamic prediction of HIV progression and mortality allows such individualised predictions to be made for HIV patients, based on monitoring of their CD4 counts. This study aims to provide predictions of patient-specific trajectories of HIV disease progression and survival.Methods: Longitudinal data on 254 HIV/AIDS patients who received ART between 2009 and 2014, and who had at least one CD4 count observed, were employed in a Bayesian joint model of disease progression, as measured by CD4 counts, and survival, to obtain individualised dynamic predictions of both processes that were updated at each visit time in the follow-up period. Different forms of association structure that relate the longitudinal CD4 biomarker and time to death were assessed; and predictions were averaged over the different models using Ba...
Background: Dental caries are a significant public health problem. It is a disease with multifact... more Background: Dental caries are a significant public health problem. It is a disease with multifactorial causes. In Sub-Sahara Africa, Ethiopia is one of the countries with a high record of dental caries. This study was to determine the risk factors affecting dental caries using both Bayesian and classical approaches. Methods: The study design was a retrospective cohort study in the period of March 2009 to March 2013 dental caries patients Hawassa Haik Poly Higher Clinic. The Bayesian logistic regression procedure was adapted to make inference about the parameters of a logistic regression model. The purpose of this method was generating the posterior distribution of the unknown parameters given both the data and some prior density for the unknown parameters. Results: From this study the prevalence of natural dental caries was 87% and non-natural dental caries were 13%. The age group of 18-25 was higher prevalence of dental caries than the other age groups. From Bayesian logistic regression, we found out that rural patients, do not clean their teeth, patients from SNNPR and age group 18-25 are statistically significant. The finding from the Bayesian statistics approach is getting popular in data analysis than classical statistics because the technique is more robust and precise. Conclusions: Bayesian approach was found to be better than classical method as the value of the standard errors in Bayesian approaches is smaller than that of classical logistic regression. The Bayesian credible interval is smaller than the length of the confidence interval for all significant risk factors. Age, sex, place of residence, region and habit of cleaning teeth was found to have a significant effect on dental caries patients.
Background: Dental caries are a significant public health problem. It is a disease with multifact... more Background: Dental caries are a significant public health problem. It is a disease with multifactorial causes. In Sub-Sahara Africa, Ethiopia is one of the countries with a high record of dental caries. This study was to determine the risk factors affecting dental caries using both Bayesian and classical approaches. Methods: The study design was a retrospective cohort study in the period of March 2009 to March 2013 dental caries patients Hawassa Haik Poly Higher Clinic. The Bayesian logistic regression procedure was adapted to make inference about the parameters of a logistic regression model. The purpose of this method was generating the posterior distribution of the unknown parameters given both the data and some prior density for the unknown parameters. Results: From this study the prevalence of natural dental caries was 87% and non-natural dental caries were 13%. The age group of 18-25 was higher prevalence of dental caries than the other age groups. From Bayesian logistic regression, we found out that rural patients, do not clean their teeth, patients from SNNPR and age group 18-25 are statistically significant. The finding from the Bayesian statistics approach is getting popular in data analysis than classical statistics because the technique is more robust and precise. Conclusions: Bayesian approach was found to be better than classical method as the value of the standard errors in Bayesian approaches is smaller than that of classical logistic regression. The Bayesian credible interval is smaller than the length of the confidence interval for all significant risk factors. Age, sex, place of residence, region and habit of cleaning teeth was found to have a significant effect on dental caries patients.
Background: This paper studies the effect of mosquito abundance and malaria incidence in the last... more Background: This paper studies the effect of mosquito abundance and malaria incidence in the last 3 weeks, and their interaction, on the hazard of time to malaria in a previously studied cohort of children in Ethiopia. Methods: We model the mosquito abundance and time to malaria data jointly in a Bayesian framework. Results: We found that the interaction of mosquito abundance and incidence plays a prominent role on malaria risk. We quantify and compare relative risks of various factors, and determine the predominant role of the interaction between incidence and mosquito abundance in describing malaria risk. Seasonal rain patterns, distance to a water source of the households, temperature and relative humidity are all significant in explaining mosquito abundance, and through this affect malaria risk. Conclusion: Analyzing jointly the time to malaria data and the mosquito abundance allows a precise comparison of factors affecting the spread of malaria. The effect of the interaction between mosquito abundances and local presence of malaria parasites has an important effect on the hazard of time to malaria, beyond abundance alone. Each additional one km away from the dam gives an average reduction of malaria relative risk of 5.7%. The importance of the interaction between abundance and incidence leads to the hypothesis that preventive intervention could advantageously target the infectious population, in addition to mosquito control, which is the typical intervention today.
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Papers by Denekew Belay