Collagen and elastic fibers assessment of the human heart valves for age estimation in Thais using image analysis.

The study investigated the relationship between the histological compositions of the tricuspid, pulmonary, mitral, and aortic valves, and age. All 85 fresh human hearts were obtained with an age range between 20 and 90 years. The central area of the valves was conducted to analyze the density of collagen and elastic fibers by using an image analysis program. Neural network function in MATLAB was used for classification data and accuracy test of the age predictive model. Overall, a gradual increase in the density of collagen and elastic fibers was demonstrated with age in all valve types. The pulmonary valve cusps had the least density of collagen and elastic contents, whereas the most dense of collagen was found in the mitral leaflets. A similarity was noted for the elastic fibers in the tricuspid, mitral, and aortic valves. The highest correlation between the collagen (r = 0.629) and elastic fibers (r = 0.713) and age was found in the noncoronary cusp of the aortic valve. The established predictive equations using collagen and elastic fibers in the noncoronary cusp provided the standard error of ± 14.0 and 12.5 years, respectively. A 60.9% of accuracy was found in all age groups using collagen, while accuracy in elastic fibers showed 70.0% in the classification process using the neural networks. The current study provided additional data regarding age-associated changes of collagen and elastic fibers in the human heart valves in Thais and the benefits and application in age forensic identification.

Factors Associated with Suspected Developmental Delay in Thai Children Born with Low Birth Weight or Asphyxia.

OBJECTIVES: The aim of the study was to identify factors associated with a risk of suspected developmental delay (SDD) in high-risk children in Thailand. METHODS: We used data on children enrolled for developmental delay (DD) screening across Thailand collected by the Rajanagarindra Institute of Child Development, Department of Mental Health, Ministry of Public Health, Thailand. Children who were under 5 years of age with a birth weight of fewer than 2500 g and/or birth asphyxia in Thailand with high risk of DD were assessed using the Developmental Assessment for Intervention Manual (DAIM) between August 2013 and November 2019 (N = 14,314). RESULTS: The high-risk children who had a gestational age at birth of < 37 weeks (adjusted odds ratio = 1.54; 95% confidence interval = 1.39-1.70) and/or had a birth weight < 2500 g (1.22; 1.02-1.45), or had mothers who were not government officers (1.46; 1.11-1.93), had a low education level (1.36; 1.19-1.55), had a poor nutritional status (1.34; 1.09-1.65), and/or who were living in a high-altitude area (1.59; 1.32-1.91) were at a higher risk of SDD. CONCLUSIONS FOR PRACTICE: Children with a low birth weight and/or asphyxia during birth had a high risk of DD. SDD monitoring of children by community health workers and/or by developing outreach strategies, especially in underserved regions, should be considered. In addition, developing policies and guidelines, and intervention for high-risk children ought to be conducted to reduce the subsequent problems caused by the late detection of DD.

A web application for sex and stature estimation from radiographic proximal femur for a Thai population.

In both forensic and archaeological domains, the discovery of incomplete human remains is a frequent occurrence. Nevertheless, the estimation of biological profiles from such remains presents a challenge due to the absence of crucial skeletal elements, such as the skull and pelvis. This study aimed to assess the utility of the proximal femur in the forensic identification process by creating a web application for osteometric analysis of the proximal femur. The aim was to determine the sex and stature of an individual from radiographs of the left anteroposterior femur. To accomplish this, an automated method was developed for acquiring linear measurements from radiographic images of the proximal femur using Python tools. The application of Hough techniques and Canny edge detection was utilized to generate linear femoral dimensions from radiographs. A total of 354 left femora were radiographed and measured by the algorithm. The sex classification model employed in this study was the Naïve Bayes algorithm (accuracy = 91.2 %). Results indicated that Gaussian process regression (GPR) was the most effective method for estimating stature (mean error = 4.68 cm, SD = 3.93 cm). The proposed web application holds the potential to serve as a valuable asset in the realm of forensic investigations in Thailand, particularly in the estimation of biological profiles from fragmentary skeletal remains.

Stature estimation using the sacrum in a Thai population.

Stature is an essential component of biological profile analysis since it determines an individual's physical identity. Long bone dimensions are generally used to estimate the stature of skeletal remains; however, non-long bones such as the sternum, cranium, and sacrum may be necessary for some forensic situations. This study aimed to generate a regression equation for stature estimation of the skeletal remains in the Thai population. Ten measurements of the sacrum were measured from 200 dry sacra. The results revealed that the maximum anterior breadth (MAB) provided the most accurate stature prediction model among males (correlation coefficient [r]=0.53), standard error of estimation (SEE=5.94 cm), and females (r=0.48, SEE=6.34 cm). For the multiple regression model, the best multiple regression models were stature equals 41.2+0.374 (right auricular surface height [RASH])+1.072 (anterior-posterior outer diameter of S1 vertebra corpus [APOD])+0.256 (dorsal height [DH])+0.417 (transverse inner diameter of S1 vertebra corpus [TranID])+0.2 (MAB) with a SEE of 6.42 cm for combined sex. For males, stature equals 63.639+0.478 (MAB)+0.299 (DH)+0.508 (APOD) with a SEE of 5.35, and stature equals 75.181+0.362 (MAB)+0.441 (RASH)+0.132 (maximum anterior height [MAH]) with a SEE of 5.88 cm for females. This study suggests that regression equations derived from the sacrum can be used to estimate the stature of the Thai population, especially when a long bone is unavailable.

Discrimination against and Associated Stigma Experienced by Transgender Women with Intersectional Identities in Thailand.

Although Thailand is overtly open to diversity and promotes equality, discrimination of minorities based on gender, ethnicity, and/or certain occupations is unfortunately still prevalent. Society either obstructs their inclusion or accepts them but only under certain conditions. The objective of this study is to examine the discrimination of TGWs with intersectional identities within Thai society. A total of 19 TGW participants were recruited and underwent in-depth thematic interviews about their experiences of discrimination. Rechecking of the extracted information from the interview transcripts and the subsequent encoding process were conducted using the NVivo program. The results show that the median age was 30 years old, and the majority of the individuals with intersectional identities were ethnic minority TGWs (47%). The in-depth interviews were divided into four main themes, including discrimination at an educational institution, discrimination in the workplace, discrimination in daily life, and discrimination at a healthcare facility. Our findings reflect problems associated with multiple sources of discrimination aimed at transgender women with an intersectional identity in Thailand in every aspect, including harsh speech or physical abuse; occupational, social, and legal inequality; and healthcare provision disparity. Raising awareness about gender diversity and intersectionality, as well as enforcing anti-bullying legislation and anti-discrimination laws, should be continually pursued in order to protect the rights and improve the quality of life of transgender individuals with an intersectional identity.

Comparison of unweighted and item response theory-based weighted sum scoring for the Nine-Questions Depression-Rating Scale in the Northern Thai Dialect.

BACKGROUND: The Nine-Questions Depression-Rating Scale (9Q) has been developed as an alternative assessment tool for assessing the severity of depressive symptoms in Thai adults. The traditional unweighted sum scoring approach does not account for differences in the loadings of the items on the actual severity. Therefore, we developed an Item Response Theory (IRT)-based weighted sum scoring approach to provide a scoring method that is more precise than the unweighted sum score. METHODS: Secondary data from a study on the criterion-related validity of the 9Q in the northern Thai dialect was used in this study. All participants were interviewed to obtain demographic data and screened/evaluated for major depressive disorder and the severity of the associated depressive symptoms, followed by diagnosis by a psychiatrist for major depressive disorder. IRT models were used to estimate the discrimination and threshold parameters. Differential item functioning (DIF) of responses to each item between males and females was compared using likelihood-ratio tests. The IRT-based weighed sum scores of the individual items are defined as the linear combination of individual response weighted with the discrimination and threshold parameters divided by the plausible maximum score based on the graded-response model (GRM) for the 9Q score (9Q-GRM) or the nominal-response model (NRM) for categorical combinations of the intensity and frequency of symptoms from the 9Q responses (9QSF-NRM). The performances of the two scoring procedures were compared using relative precision. RESULTS: Of the 1,355 participants, 1,000 and 355 participants were randomly selected for the developmental and validation group for the IRT-based weighted scoring, respectively. the gender-related DIF were presented for items 2 and 5 for the 9Q-GRM, while most items (except for items 3 and 6) for the 9QSF-NRM, which could be used to separately estimate the parameters between genders. The 9Q-GRM model accounting for DIF had a higher precision (16.7%) than the unweighted sum-score approach. DISCUSSION: Our findings suggest that weighted sum scoring with the IRT parameters can improve the scoring when using 9Q to measure the severity of the depressive symptoms in Thai adults. Accounting for DIF between the genders resulted in higher precision for IRT-based weighted scoring.

Spatial Distribution of Head and Neck Cancer in Chiang Mai, Thailand.

BACKGROUND: The incidence of Head and neck (HN) cancers in Thailand is rising and survival rates not improving. Variations of its incidence among geographical areas may due to various contributing factors. METHODS: We focused on data from 25 districts within Chiang Mai province, Thailand. The temporal change was described separately into two periods, 2007-2012 and 2013-2018. The OpenBUGS and the Quantum Geographic Information System were utilized to determine the geographical patterns in the incidence of HN cancer and focus on oropharynx. RESULTS: The number of new cases of HN cancer was 1,186, of which 835 cases (70%) were male. Among those patients 548 diagnosed in 2007-2012 and 638 diagnose in 2013-2018. High risk patterns of both overall HN and oropharyngeal cancer incidences were found in the central and southern areas of the province in 2007-2013. However, the geographical patterns of the incidence of oropharyngeal cancer showed the changed pattern, with high RR in central and northern areas in more recent period. Over two periods, the RR of the cancers incidence decrease. The RR of oropharyngeal increased in Fang district and it remained high in Mueang district. CONCLUSION: This study have highlighted specific areas with a high risk of head and neck cancer and oropharyngeal cancer incidences in Chiang Mai province, along with the spatial inequalities in their distributions, with cluster formation. These results may be helpful in guiding any strategy put in place to respond to the high risk incidence of the cancers in specific areas.

The development and testing of Thai facial soft tissue thickness data in three-dimensional computerized forensic facial reconstruction.

Forensic facial reconstruction is a useful tool to assist the public in recognizing human remains, leading to positive forensic investigation outcomes. To reproduce a virtual face, facial soft tissue thickness is one of the major guidelines to reach the accuracy and reliability for three-dimensional computerized facial reconstruction, a method that is making a significant contribution to improving forensic investigation and identification. This study aimed to develop a facial soft tissue thickness dataset for a Thai population, and test its reliability in the context of facial reconstruction. Three-dimensional facial reconstruction was conducted on four skulls (2 males and 2 females, with ages ranging between 51 to 60 years). Two main tools of three-dimensional computer animation and modeling software-Blender and Autodesk Maya-were used to rebuild the three-dimensional virtual face. The three-dimensional coordinate (x, y, z) cutaneous landmarks on the mesh templates were aligned homologous to the facial soft tissue thickness markers on the three-dimensional skull model. The final three-dimensional virtual face was compared to the target frontal photograph using face pool comparison. Four three-dimensional virtual faces were matched at low to moderate levels, ranging from 30% to 70% accuracy. These results demonstrate that the facial soft tissue thickness database of a Thai population applied in this study could be useful for three-dimensional computerized facial reconstruction purposes.

Sex estimation using ulna in a Thai population / Estimación del sexo utilizando la ulna en una población tailandesa

SUMMARY: Sex estimation from fragmentary bone remain is still challenge for forensic pathologist. Ulna has been reported useful for sex estimation by metric analysis. This study generated sex estimation function for fragment and complete of ulnar bone in a Thai population. The function was generated from 200 pairs of ulnar bone, and others 20 pair of ulnar bone were used for test the accuracy of the functions. Olecranon width was the best single variable for sex predicting of proximal part of ulna, which right olecranon width could be classified the sex 90.5 %. While distal end width of ulna was the variable for predicting the sex of distal part, which left distal end width could be classified the sex with 83.0 %. Stepwise discriminant function analysis was applied to proximal part. For proximal part of right ulna 4 measurements were selected (inferior-medial trochlear notch length, olecranon width, olecranon-coronoid process length, and maximum proximal ulnar width), while the left side, superior trochlear notch width, olecranon width, and maximum proximal ulnar width were chosen, and their functions could be predicted the sex with 91.0 % and 90.0 %, respectively. Our results indicated the ulnar bone had high ability for estimating the sex in a Thai population.

RESUMEN: La estimación del sexo a partir de restos óseos fragmentarios sigue siendo un desafío para el patólogo forense. Se ha informado de la utilidad de la ulna para la estimación del sexo mediante análisis métrico. En este estudio se analizó la estimación del sexo para un fragmento y de la ulna completa en una población tailandesa. La función se generó a partir de 200 pares de ulnas y se utilizaron otras 20 pares de ulnas estimando la precisión de las funciones. El ancho del olécranon fue la mejor variable individual para predecir el sexo en la parte proximal de la ulna (90, 5 %). Si bien el ancho del extremo distal de la ulna fue la variable para predecir el sexo, el ancho del extremo distal izquierdo podría clasificarse por sexo con un 83,0 % de certeza. Se aplicó un análisis de función discriminante escalonada a la parte proximal. Para la parte proximal de la ulna derecha se seleccionaron 4 medidas (longitud de la incisura troclear inferior-medial, ancho del olécranon, longitud del proceso olecraneano-proceso coronoides y ancho ulnar proximal máximo), mientras que en el lado izquierdo, fue determinado el ancho de la incisura superior troclear, ancho del olécranon y ancho ulnar proximal máximo. Se eligió el ancho, y se pudo predecir el sexo en el 91,0 % y 90,0 % de los casos, respectivamente. Nuestros resultados indicaron que la ulna tenía una alta capacidad para estimar el sexo en una población tailandesa.

Sex estimation using radius in a Thai population.

The estimation of sex is an essential component of forensic osteological analyses, and the potential of an incomplete radius for sex determination of human remains is investigated. The present study was conducted on 200 left-right pairs of radial bone from a northern Thai population (100 males and 100 females). The most dimorphic single parameter was maximum head diameter (MDH) with accuracies 92.0% for the right side and 90.5% for the left side. At the distal part of radius, the distal end width of the radius (RDEW) was the best sex indicator, in which the sex classification accuracies were 91.5% and 89.0%, for the right and left sides, respectively. Stepwise discriminant function analysis was performed for all measurements and specified separately to the proximal and distal radius. The circumference of the radial neck, head-tuberosity length, MDH, and RDEW were selected for the stepwise procedure as these parameters produced the best correct classification results for both sides. The use of proximal radius for sex estimation was examined, with accuracies of 95.0% and 93.0% for the right and left sides, respectively. The sex classification functions for distal radius provided the accuracies of 92.5% and 89.5%, for the right and left sides, respectively. In summary, the fragments of radius indicated a high ability to estimate sex in the Northern Thai population.

Sex and stature estimation from adult lumbar vertebrae in a Thai population based on image analysis / Estimación de sexo y estatura de vértebras lumbares adultas en una población Tailandesa basada en análisis de imagen

SUMMARY: Although molecular techniques evolved considerably in last years, anthropological methods of assessing skeletal remains, continues to be an important tool in the identification process in medico legal investigations. The objective of this study was to develop a discriminant function equation for estimating sex and stature using several measurements of lumbar vertebrae in a Thai population. We studied 150 lumbar columns (75 male and 75 female) age range of 22 to 89 years from the Forensic Osteology Research Center, Chiang Mai University, Thailand. The quantitative variables with sex were analyzed by the discriminant function analysis and that with stature were calculated using linear regression. The pixel density of the major axis of the trabecular surface of superior endplate of the first lumbar vertebra had the most accuracy in sex determination. The regression equation with quantitative variables in stature estimation described 32.3 % of the total variance with standard error of estimate of 7.736 cm. Lumbar vertebrae can be used as part of the stature and sex quantitatively and qualitatively estimating in Thais incomplete skeletal remains.

RESUMEN: Los métodos antropológicos de evaluación del esqueleto siguen siendo una herramienta importante en el proceso de identificación en las investigaciones médico-legales. El objetivo de este estudio fue desarrollar una ecuación de función discriminante para estimar el sexo y la estatura utilizando varias medidas de las vértebras lumbares en una población tailandesa. Se estudiaron 150 columnas lumbares (75 hombres y 75 mujeres) con un rango etario de 22 a 89 años del Centro de Investigación de Osteología Forense, Universidad de Chiang Mai, Tailandia. Las variables cuantitativas de sexo se analizaron mediante el análisis de función discriminante y la estatura fue calculada mediante regresión lineal. En cuanto a la determinación de sexo, la densidad de píxeles del eje mayor de superficie trabecular de la placa terminal superior de la primera vértebra lumbar fue de mayor precisión. La ecuación de regresión con variables cuantitativas en la estimación de la estatura describió el 32,3 % de la varianza total con el error estándar de estimación de 7,736 cm. Las vértebras lumbares se pueden utilizar como parte de la estatura y el sexo, estimando cuantitativa y cualitativamente los restos esqueléticos incompletos en sujetos tailandeses.

The estimation of age from elastic fibers in the tunica media of the aortic wall in a thai population: a preliminary study using aorta image analysis.

Image analysis has an increasing role in the identification of individuals in forensic application. Beside the bones, microstructural of arteries can be used in age estimation study. Aorta is the largest elastic artery which consists of many elastic fibers. Elastin in arterial wall highly resist to chemical and physical influence. The purposes of the study were to quantify elastic fibers in tunica media in each location of the aorta and examine the correlation between elastic fibers and age by using image analysis program. A total of 36 human aortas were dissected in 4 locations. The aortas were obtained from cadavers with an age range of 20 to 90 years. Specimens were stained with Elastic Van Gieson staining. Histological images were investigated about elastic fibers using light microscope with cellSens program and aorta image analysis was used for the evaluation of data. The results showed that the mean percentage density of elastic fibers in the ascending aorta and the aortic arch increased. However, the mean percentage density of elastic fibers decreased in the 31 to 40 years age group in the thoracic aorta and the abdominal aorta and decreased in each location of aorta continuously until 81 to 90 years. The abdominal aorta showed the highest correlation with age (r=0.732) followed by the thoracic aorta, the aortic arch and the ascending aorta, respectively. Changes in the percentage density of elastic fibers in the tunica media of the aortic wall can be used to add information to age estimation for identification purposes.

Image analysis of morphometric evaluation from the heart valves for age estimation in Thai population / Análisis de la evaluación morfométrica de las valvas cardíacas para la estimación de la edad en la población tailandesa

Determination of age represents one of the most important aspects in forensic identification. Through aging, changes can occur in morphological structures of the heart valves. The objective is to examine the relationship between the dimensions of the rigth atrioventricular (tricuspid), pulmonary, left atrioventricular (mitral), and aortic valves and age at death. Sixty fresh human hearts were obtained from Department of Anatomy and Department of Forensic Medicine, Faculty of medicine, Chiang Mai University, Thailand. The age of individuals was between 20-90 years. We investigated the morphometric parameters of the valves were taken including: valve circumference, length, the height and area of each leaflet. All parameters were measured by using specific image analysis software. The correlation test and predictive equation were established. The positive correlation between the circumference, area of posterior leaflet, height of anterior leaflet, and area of anterior leaflet of the rigth atrioventricular valve were found. The left atrioventricular valve showed correlation with age in circumference, length and area of posterior leaflet. For the pulmonary and aortic valves, there were correlated between circumference at sinotubular junction and leaflet sizes in almost leaflets. The circumference at sinotubular junction of the pulmonary valve was highest significantly correlation with age (r=0.693). The predictive equation was age = -3.659+0.652(Circumference at sinotubular junction of the pulmonary valve) with standard error of ± 14.7 years. Additional knowledge of morphometric features in human heart valves and its relationship with age could be used as age indicator in forensic field.

La determinación de la edad representa uno de los aspectos más importantes en la identificación forense. Pueden ocurrir cambios a través del envejecimiento, en las estructuras morfológicas de las válvulas cardíacas. El objetivo de este estudio fue examinar la relación entre las dimensiones de las valvas atrioventricular derecha (tricúspide), pulmonar, atrioventricular izquierda (mitral) y aórtica, y la edad en relación a la muerte. Se obtuvieron sesenta corazones humanos frescos del Departamento de Anatomía y el Departamento de Medicina Forense de la Facultad de Medicina de la Universidad de Chiang Mai, Tailandia. La edad de las personas fluctuaba entre los 20 y 90 años. Investigamos los parámetros morfométricos de las valvas analizadas, incluyendo: circunferencia de la valva, longitud, altura y área de cada valva. Todos los parámetros se midieron utilizando un software de análisis de imagen específico. Se estableció la prueba de correlación y la ecuación predictiva. Se encontró la correlación positiva entre la circunferencia, el área de la valvula posterior, la altura de la valvula anterior y el área de la valvula anterior de la valva atrioventricular derecha. La valva atrioventricular izquierda mostró correlación con la edad en la circunferencia, longitud y área de la valvula posterior. Para las valvas pulmonar y aórtica, se correlacionó entre la circunferencia en la unión sinotubular y el tamaño de las válvulas. La circunferencia en la unión sinotubular de la valva pulmonar fue la mayor correlación significativa con la edad (r = 0,693). La ecuación predictiva fue edad = -3,659 + 0,652 (circunferencia en la unión sinotubular de la valva pulmonar) con error estándar de ± 14,7 años. El conocimiento adicional de las características morfométricas en las valvas cardíacas humanas y su relación con la edad podría usarse como indicador de edad en el campo forense.

Age estimation from ossification of sternum and true ribs using 3D post-mortem CT images in a Japanese population.

Age estimation of cadavers from post-mortem "chest plate" using conventional radiography, which involves radiographic assessment of ossification around the sternum and rib ends, has been evaluated without fruitful results. This study examined the value of images of the chest plate obtained by three-dimensional post-mortem CT for estimation of age at time of death in a Japanese population. Five chest plate ossification scores were evaluated in 320 subjects, including ossification of the first costal cartilage (OF), ossification of the second to seventh costal cartilages at the rib (OR) and sternal (OS) ends, fusion of the manubriosternal joint (FM), and fusion of the xiphisternal joint (FX). OS was found to have the highest correlation with age while FM had no significant correlation. The best composite score for age estimation was the summative score for both sides of the OS and the right side of the OF and FX, for which the coefficient of determination (R2) and the standard error of estimation (SEE) were 0.608 and 12.44 years, respectively, for men and 0.590 and 14.65 years for women. The accuracy of the model was tested in a further 26 male and 24 female subjects, and the accuracy rate within the first SEE was 57.69% and 70.83%, respectively. This rapid and non-invasive method of age estimation in the chest plate area is superior to conventional methods and could be useful for estimation of age at time of death in the Japanese population.

Three-Dimensional Prediction of the Nose for Facial Approximation in a Thai Population.

Most of the previous studies about nose prediction were concentrated only some landmarks of the nose. This study aimed to generate prediction equations for ten landmarks of the nose in the midline and alar regions for forensic facial approximation. The six midline landmarks were the sellion, nasion-pronasale posterior, nasion-pronasale anterior, pronasale, nasal drop, and subnasale. The four landmarks of the alar region were the alare, superior alar groove, posterior alar groove, and inferior alar groove. We used the skull landmarks in the nasal, zygomatic, and maxillary bone to predict the landmarks of the nose. Cone-beam computed tomography scans of 108 Thai subjects with normal BMI and age ranging from 21.0 to 50.9 years were obtained in a sitting position. The data were converted into three-dimensional (3-D) images of the skull and face. The Cartesian coordinates of the landmarks of the skull and nose were used to formulate the multiple regression equations. The formulated equations were tested in 24 new subjects. The mean differences in the predicted midline landmarks varied between -0.4 mm and 0.5 mm, whereas those for bilateral landmarks varied between -1.0 mm and 1.4 mm. In conclusion, the prediction equations formulated here will be beneficial for facial approximation of the nose in a Thai population.

Age estimation equations using vertebral osteophyte formation in a Thai population: comparison and modified osteophyte scoring method.

Age estimation from skeletal remains is an important step in forensic biological identification. The main objective of this study is to develop an age estimation equation for the Thai population from vertebral osteophytes. Each vertebra in the cervical, thoracic and lumbar segments was scored for degree of osteophyte formation. Classification was carried out in accordance with the criteria established by Snodgrass and Watanabe, and used a new modified score of the length of vertebral osteophyte for age estimation. The sample included 400 individuals (262 males, 138 females) ranging in age from 22 to 97 years. A sample of Thai vertebral columns was used, the columns being divided into the following groups of vertebrae: cervical (C2-C7), thoracic (T1-T12), and lumbar (L1-L5). Each vertebra was scored for the degree of osteophyte formation and the accumulated data was analyzed statistically. Correlation coefficients and R-squared from mean in lumbar vertebrae for females of criteria established by the method of Snodgrass and Watanabe, the new modified score by length of vertebral osteophytes were 0.801 and 0.642 (P<0.01); 0.755 and 0.57 (P<0.01); 0.786 and 0.618 (P<0.01), respectively. This study presents all 23 subcategories (C2-L5) of the vertebrae to apply in real situations, showing all age estimation equations for males, females and combined sexes of unknown sex. One application of this study is age estimation when dealing with forensic cases in the Thai population.

Efficacy of three-dimensional cinematic rendering computed tomography images in visualizing features related to age estimation in pelvic bones.

Morphological changes on the surface of the pelvic bone can be used to estimate the age at death of a person. These features can be visualized using three dimensional computed tomography (3D CT) images. A newly introduced 3D CT technique, cinematic volume rendering, improves visualization of the surface of bones by integrating the effect of light on the images. The aim of this study is to evaluate the efficacy of this 3D CT technique in visualizing features related to age estimation in pelvic bones. Dry pelvic bones of 35 subjects were scanned and then 3D reconstruction of the images was performed using the cinematic rendering technique. The 3D CT images of the pubic symphyses and the auricular surfaces were interpreted by two radiologists and a forensic osteologist using age estimation features derived from the Suchey-Brooks and the Buckberry-Chamberlain methods The interpretation of the dry pelvic bones was done by an expert anatomist and used as a gold standard. The percentages of correct interpretations and level of agreement in grading using 3D CT and using dry bones were high for features in the pubic symphyses including surface patterns (100%, k=1), presence of lower extremities (100%, k=1), and patterns of pubic rims (91.4%, range 87.5-100%, k=0.88). In the auricular surface of the ilium, all specimens with an apical activity were correctly interpreted (100%, k=1), but detection was moderate to poor for transverse organization (71.4%, k=0.43), macroporosity (70%, k=0.38.), and microporosity (52.9%, k=0.25). Cinematic volume rendering has a high level of efficacy in identifying age-related features on pubic symphyses, but it inadequately displays features on the auricular surface.

Age Estimation of Lumbar Vertebrae by Visual Assessment in a Thai Population.

BACKGROUND: The age estimation of bone is essential for identification of the unknown-identity persons in both forensic and anthropological sciences. The lumbar vertebrae carry the most weight; hence, they have more biomechanical stress than any other vertebrae. As a result, the degenerative changes commonly occur in them. However, the estimation from visual assessment in lumbar vertebrae has not been reported in a Thai population. OBJECTIVE: To evaluate the age estimation from the degree of osteophyte formation, the macroporosity, and the cortical surface to develop equations of lumbar vertebrae. MATERIALS AND METHODS: A total of 250 lumbar columns (125 males and 125 females) in age range of 22 to 89 years were collected from the Forensic Osteology Research Center (FORC), Faculty of Medicine, Chiang Mai University. RESULT: The most appropriate linear regression equation was used to estimate age by the inferior surface of L1 vertebra (R2= 0.408) with the standard error of 11.686 years. CONCLUSION: It was clear to recognize that three morphological aspects will be useful methods for forensic situations.

Risk patterns of lung cancer mortality in northern Thailand.

BACKGROUND: Over the past decade, lung cancers have exhibited a disproportionately high mortality and increasing mortality trend in Thailand, especially in the northern region, and prevention strategies have consequently become more important in this region. Spatial analysis studies may be helpful in guiding any strategy put in place to respond to the risk of lung cancer mortality in specific areas. The aim of our study was to identify risk patterns for lung cancer mortality within the northern region of Thailand. METHODS: In the spatial analysis, the relative risk (RR) was used as a measure of the risk of lung cancer mortality in 81 districts of northern Thailand between 2008 and 2017. The RR was estimated according to the Besag-York-Mollié autoregressive spatial model performed using the OpenBUGS routine in the R statistical software package. We presented the overall and gender specific lung cancer mortality risk patterns of the region using the Quantum Geographic Information System. RESULTS: The overall risk of lung cancer mortality was the highest in the west of northern Thailand, especially in the Hang Dong, Doi Lo, and San Pa Tong districts. For both genders, the risk patterns of lung cancer mortality indicated a high risk in the west of northern Thailand, with females being at a higher risk than males. CONCLUSIONS: There was distinct geographical variation in risk patterns of lung cancer mortality in Thailand. Differences could be related to differences in risk factors such as ground-based radon and air pollution. This study provides a starting point for estimating the spatial pattern of the risk of lung cancer mortality and for examining associations between geographic risk factors and lung mortality for further studies.

Age estimation approaches using cranial suture closure: A validation study on a Thai population.

Cranial suture closure, one of the most commonly used age estimation methods, for decades, however, is often viewed with caution and its reliability is still debated. Few methods of estimating age using the skeleton, especially cranial suture, have been tested on Thais. This study aims to test the traditional aging techniques using cranial suture closure on Thai individuals in order to identify the error rate of each method when applied to a Thai sample. Meindl and Lovejoy (1985), Acsádi and Nemeskéri (1970), and Mann (1991) methods were applied to 175 Thai dry crania. Bias and inaccuracy in the Meindl and Lovejoy, Acsádi and Nemeskéri, and Mann methods resulted in overestimation in young adults and underestimation in older individuals with an inaccuracy range of approximately 13-22 years. The Mann method approached 100% in predicting age in older males, but the method did not fare as well on Thai females. The results confirm inter-population variation does exist. Additionally, differences in age composition between populations used to develop the methods and Thais may lead to an increase in error. This study indicates that these three aging methods should be used in conjunction with other techniques. Further research which develops specific methods for Thais might give better results for age estimation.