The Data Generation Mechanism: Relationship Between Constructs and Their Indicators / O Mecanismo de Geração de Dados: Relação entre Construtos e seus Indicadores

Abstract The choice of statistical data analysis should be guided by a critical analysis that supports the theoretical relationship between the construct and its indicators. This theoretical article reviews the three main existing psychometric paradigms and their proposals for explaining the relationship between indicators and their constructs. The discussion begins with the standard paradigm that guides the construction and analysis of data in psychology, reflective model. Then, a description of the formative models is performed and finally the Network Analysis as an alternative. The definitions, consequences, and limitations of the use of each measurement model are presented such as a reflection on making decisions about which data generation mechanisms are more appropriate.

Resumo A escolha da análise estatística de dados deveria ser guiada por uma análise crítica que fundamenta a relação teórica entre construto e seus indicadores. Este teórico artigo faz uma revisão dos três principais paradigmas psicométricos e suas propostas de explicação da relação entre os indicadores e seus construtos. A discussão é iniciada com o paradigma padrão que guia a construção e análise de dados na psicologia, os modelos reflexivos. Em seguida, é realizada uma descrição dos modelos formativos e, por fim, a proposta da Análise de Redes como alternativa. São apresentadas as definições, consequências e limitações do uso de cada modelo de medida, bem como uma reflexão na tomada de decisão sobre quais mecanismos de geração de dados são mais apropriados.

Age estimation of immature human skeletal remains from mandibular and cranial bone dimensions in the postnatal period.

Age estimation is one of the crucial first steps in the identification of human skeletal remains in both forensic and archeological contexts. In the postnatal period, age is traditionally estimated from dental development or skeletal growth, typically long bone diaphyseal length. However, in many occasions other methods are required. This study provides alternative means of estimating age of juvenile remains from the size of several cranial bones and the mandible. A sample of 185 identified juvenile skeletons between birth and 13 years of age from two European collections were used (Lisbon and Spitalfields). Measurements of the frontal, occipital-lateralis, occipital-basilaris, occipital-squamous, zygomatic, maxilla, and mandible were used to calculate classical calibration regression formulae for the sexes combined. The sample was divided into three age groups birth-2 years, 2-6 years, and 2-12.9 years, depending on bone and its growth trajectory. For all the bones, measurements of the youngest age groups yielded the most precise age estimates. The vault bones on average yielded the best performing models, with the frontal bone having the most precise of all. The mandible performed on par with the best performing cranial bones, particularly in individuals under the age of 2 years. This study provides one of the most comprehensive approaches to juvenile age estimation based on bones of the skull, providing a resource that potentially can help estimate age of juvenile skeletons from a variety of circumstances.

Testing the cross-applicability of juvenile sex estimation from diaphyseal dimensions.

Sex estimation is a crucial component of the biological profile. Stull et al. (2017) have proposed a promising juvenile sex estimation method using long bone measurements taken from a South African sample, providing relatively high classification accuracies and made easy to use via the KidStats web-based app. In this study, we test the models developed by Stull et al. (2017) on an external historic population from Lisbon, Portugal, in order to determine whether the models can be reliably applied to archeological and forensic populations outside of the original population sample. The study sample consisted of 102 individuals (45 females and 57 males) aged under 13 years at death from the Lisbon identified skeletal collection. Measurements from these individuals were used to test the flexible discriminant analysis (FDA) models given by Stull et al. (2017). Allocation accuracies were calculated for boys and girls and children over and under 2 years separately and combined. Our findings show that the models developed by Stull et al. (2017) yield poor accuracy when applied to our external population and thus can potentially be misapplied on archeological skeletal remains or forensic remains of unknown origin. A number of statistical issues may explain why models fail to be transportable or even generalizable, namely multicollinearity, model overfitting and overly optimist bootstrapped cross-validation rates. It is also likely that population differences in size and sexual size dimorphism also affected the applicability of the models. We emphasize the importance of externally validating prediction models, particularly if they are intended to be applied across populations. Our study addresses Stull and co-worker's request for further validation of the method on populations outside of South Africa, as the models cannot be confidently applied in the field until it has been externally validated.

Does age estimated from teeth forming in different early life periods show differential discrepancy with known age?

OBJECTIVES: The aim of this study is to explore growth discrepancies in the dentition of impoverished children and examine how dental development is impacted by environmental influences throughout childhood, thereby identifying which teeth are more sensitive to the effects of biocultural factors and are consequently less useful to predict age. METHODS: Length measurements of developing teeth (deciduous and permanent) were taken from individuals of known age and sex (n = 61) from the Certosa collection, a 19th century skeletal assemblage representing Italian children of low socioeconomic status. Discrepancies between age estimates based on tooth length and chronological age were calculated, and the accuracy and precision of age prediction between earlier forming teeth and later forming teeth were compared. RESULTS: Deciduous teeth produced more precise dental age estimates (mean age discrepancy -0.092 years), while discrepancies between chronological age and age based on developing permanent dentition were larger (-0.628 years). The difference between these discrepancies in age estimates for deciduous and permanent teeth was significant (p < 0.001), indicating that age prediction from deciduous tooth length is more accurate than age predicted using permanent tooth length. CONCLUSION: An increasing variation and delay in tooth length for age reflects increasing susceptibility to biocultural factors, which impacts tooth growth during the course of childhood. Teeth whose development occurs earlier in life are less variable in their growth and provide more accurate estimations of age as a result.

Socioeconomic differences in permanent teeth mineralization of Portuguese girls and boys from Porto, Portugal.

Purpose: Socioeconomic differences in dental maturation can be used to examine the impact of environmental factors on dental maturation. The purpose of this study is to assess socioeconomic differences in dental maturation of the seven permanent mandibular teeth (I1-M2). Methods: A total of 2114 panoramic radiographs of Portuguese children, adolescents and young adults were studied. The sample was divided into a high socioeconomic status (SES) (n = 925), and a low SES group (n = 1189). Ages ranged between 5 and 26 years. Demirjian's stages were used to assess the maturation of the seven mandibular teeth on the left side. Median-age of attainment of each stage and each tooth was calculated and compared between groups using binary logistic regression. Results: Low SES girls showed a consistent advancement in dental maturation across the entire dentition. Low SES boys, however, showed more often a delayed maturation relative to their high SES counterparts, but this pattern was not consistent and a clear socioeconomic difference seems to be absent in boys. Conclusions: While this study was not able to further explore the causes of the dental advancement in girls, it is hypothesized that it might be related to a higher prevalence of overweight/obesity, and possibly caries, in low SES girls, compared to the SES difference in prevalence in boys.

Lack of biological mortality bias in the timing of dental formation in contemporary children: Implications for the study of past populations.

OBJECTIVES: Biological mortality bias is the idea that individuals who perish (non-survivors) are biologically distinct from those who survive (survivors). If biological mortality bias is large enough, bioarchaeological studies of nonsurvivors (skeletal samples) cannot accurately represent the experiences of the survivors of that population. This effect is particularly problematic for the study of juvenile individuals, as growth is particularly sensitive to environmental insults. In this study, we test whether biological mortality bias exists in one dimension of growth, namely dental development. MATERIALS AND METHODS: Postmortem computed tomography scans of 206 children aged 12 years and younger at death were collected from two institutions in the United States and Australia. The sample was separated into children dying from natural causes as proxies for non-survivors and from accidental causes as proxies for survivors. Differences in the timing of dental development were assessed using sequential logistic regressions between dental formation stages and residual analysis of dental minus chronological age. RESULTS: No consistent delay in age of attainment of dental stages was documented between survivors and non-survivors. Delays between survivors and non-survivors in dental relative to chronological age were greatest for infants, and were greater for females than for males. DISCUSSION: Lack of biological mortality bias in dental development reinforces confidence in juvenile age estimates and therefore in skeletal growth profiles and growth studies. As dental development is known to be less environmentally sensitive than skeletal growth and development, further studies should examine biological mortality bias in long bone length.

Juvenile Body Mass Estimation from the Femur Using Postmortem Computed Tomography Data.

Skeletal estimation methods to reconstruct the juvenile biological profile are largely limited to those estimating age and, to a lesser extent, sex. While body mass is not generally estimated as part of the biological profile in forensic investigations, this is a logical candidate for inclusion in the forensic biological profile, as it has long been of interest in paleoanthropology and several methods to estimate juvenile body mass currently exist. To explore the performance of body mass estimation for juveniles, the authors tested the accuracy and precision of previously published panel regression formulae using two femoral measurements: the breadth of the distal metaphysis and the cross-sectional polar moment of inertia (J). The test sample consisted of measurements of 94 individuals from birth to 12.5 years of age, taken from postmortem computed tomography scans housed at the Office of the Medical Investigator, New Mexico, USA. Results indicate that body mass estimates are more accurate when estimated from cross-sectional than from metaphyseal measures. Both formulae, however, consistently underestimated weight, and the magnitude of the underestimation increased exponentially with age. This suggests that, contrary to what others have argued, body mass estimation is complicated by population variation in body composition. This study reinforces the importance of documenting and investigating the ontogeny of human variation. The global increase in medical imaging in clinical settings can be leveraged to obtain skeletal data for juveniles from a wide range of ontogenic environments, marking an exciting time for the study of human variation.

Comment on 'Krapina atlases suggest a high prevalence of anatomical variations in the first cervical vertebra of Neanderthals'.

A review of the observation of an anterior cleft on the atlas of a Neanderthal from Krapina.

Severe skeletal lesions, osteopenia and growth deficit in a child with pulmonary tuberculosis (mid-20th century, Portugal).

OBJECTIVE: This case-study provides a summary of skeletal lesions seen in a case of diagnosed juvenile pulmonary tuberculosis with extensive multifocal bony lesions. MATERIALS: Skeleton of a 9-year-old girl who died in the 1940s in Lisbon, Portugal. The remains of this individual are part of the Lisbon skeletal reference collection curated at the National Museum of Natural History and Science. METHODS: Lesions and paleopathological conditions were identified and documented through macroscopic, radiographic, computed tomographic, and mammographic analysis. RESULTS: The skeleton shows a variety of lytic lesions on the ribs and thoracic vertebrae including complete destruction of the bodies and fusion of the vertebral arches of four vertebrae, kyphosis, and scoliosis. Further pathological conditions were identified, including bone erosion, premature fusion of the left femoral head and greater trochanter, and abnormal size and shape changes to the lower limbs including loss of bone mass and stunting of the long bones. CONCLUSIONS: Skeletal lesions are indicative of spondylitis, Pott's disease, and prolonged bedrest. SIGNIFICANCE: This case is one of the few examples of confirmed juvenile pulmonary tuberculosis with skeletal lesions prior to the antibiotic era. As such, it provides a reference for the skeletal abnormalities which may be observed in archaeological tuberculosis cases. LIMITATIONS: Pulmonary tuberculosis was recorded as cause of death, however there is no documentation to know the length of illness period or the existence of any comorbidities. SUGGESTIONS FOR FURTHER RESEARCH: Consideration of multi-focal lesions is recommended when analyzing individuals with suspected tuberculosis.

Historical, demographic, curatorial and legal aspects of the BoneMedLeg human skeletal reference collection (Porto, Portugal).

The BoneMedLeg research project was developed to address current research concerns related to the use of skeletal reference collections for forensic purposes. These concerns were partly addressed by amassing a new reference collection which incorporates unclaimed human remains sourced from two municipal cemeteries in the city of Porto, Portugal. Amassed between 2012 and 2014 the collection was developed with permission from and in partnership with the Municipality of Porto, in a manner that is similar to that of other skeletal reference collections in Portugal. Traditionally, municipalities have bequeathed human remains that are cleared from temporary primary and secondary burial plots at local cemeteries and deemed unclaimed, to museums and universities for research purposes. The BoneMedLeg collection currently includes a total of 95 individuals, of which only 81 are fully identified (38 males and 43 females), with ages ranging from 21 days to 94 years, and a mean age of about 62 years. Years of death range from 1969 to 2003, and years of birth from 1891 to 1969. Only about half of the individuals are documented as to cause of death, which includes a considerable diversity of etiologies, from oncological to cardiovascular system disorders, and also traumatic injuries. The collection is more representative of an unskilled working class and aged population, due to one of the main sourced cemeteries disproportionately serving more socioeconomic disadvantaged communities and reflecting the demographics of the city over the past 40 years. In addition to describing the history and curatorial process of the collection in detail, this paper also discusses its broad legal framework and potential biases in its profile and composition which can inform and help plan future research projects.

Age estimation in three distinct east Asian population groups using southern Han Chinese dental reference dataset.

BACKGROUND: Dental age estimation can assist in the identification of victims following natural disasters and it can also help to solve birth date disputes in individuals involved in criminal activities. A reference dataset (RDS) has been developed from the dental development of 2306 subjects of southern Han Chinese origin and subsequently validated. This study aimed to test the applicability of the southern Han Chinese dental maturation RDS on three distinct East Asian population groups. METHODS: A total of 953 dental panoramic radiographs of subjects aged 2 to 24 years were obtained from Philippines, Thailand and Japan. The staging of dental development was conducted according to Anglo-Canadian classification system. The dental age (DA) was calculated using six methods; one un-weighted average and five weighted average (n-tds, sd-tds, se-tds, 1/sd-tds, 1/se-tds) methods based on the scores of the southern Han Chinese RDS. Statistical significance was set at p < 0.05 and the variation between chronological age (CA) and DA was evaluated using paired t-test and Bland & Altman scatter plots. RESULTS: From six dental age calculations, all methods of DA accurately estimated the age of Japanese and few methods in Filipino subjects (n-tds, 1/sd-tds, 1/se-tds). There was consistent overestimation of age for all the methods for Thai females (p < 0.05). CONCLUSIONS: The southern Han Chinese dental reference dataset was shown to be most accurate for Japanese, followed by Thai males and it was particularly ineffective for Filipinos and Thai females.

Stress, parenting and family support in attention deficit/shyperactivity disorder / Estresse, parentalidade e suporte familiar no transtorno de déficit de atenção/hiperatividade / Estrés, parentalidad y soporte familiar en el trastorno de déficit de atención/hiperactividad

Attention Deficit/Hyperactivity Disorder (ADHD) causes impairments in child development. Parents of children with this diagnosis may present stress, problems in managing rules and limits, compromising parenting style, besides perceiving family support as low. The objectives of the study were to characterize the stress, parenting style and perception of family support in parents of children with ADHD, establishing relationships between these variables. For this, 42 parents (fathers and mothers) responded to Lipp's Stress Symptoms Inventory for Adults (LSSI), the Inventory of Parenting Styles (IPS) and the Family Support Perception Inventory (FSPI). The results show that the mothers presented more stress than the fathers; there was also an association of mothers' stress with negative parenting practices and low perception of family support. Another finding was that the higher the child's age, the worse the parenting style presented by the family. New research should support this data.

O transtorno de déficit de atenção/hiperatividade (TDAH) gera prejuízos para o desenvolvimento infantil. Pais de crianças com esse diagnóstico podem apresentar estresse e problemas no gerenciamento de limites, comprometendo o estilo parental, além de perceberem o suporte familiar como baixo. O objetivo do estudo foi caracterizar estresse, estilo parental e percepção de suporte familiar em pais de crianças com TDAH, estabelecendo relações entre essas variáveis. Assim, 42 pais (pai e mãe) responderam ao Inventário de Sintomas de Stress para Adultos de Lipp (ISSL), Inventário de Estilos Parentais (IEP) e Inventário de Percepção de Suporte Familiar (IPSF). Os resultados indicaram que as mães apresentaram mais estresse do que os pais; também houve associação do estresse das mães com práticas parentais negativas e baixa percepção de suporte familiar. Outro achado foi que, quanto maior a idade da criança, pior o estilo parental que a família apresenta. Novas pesquisas devem dar apoio a esses dados.

El trastorno de déficit de atención/hiperactividad (TDAH) genera perjuicios para el desarrollo infantil. Los padres de niños con este diagnóstico pueden presentar estrés, problemas en gestión de límites, comprometiendo el estilo parental, además de percibir el soporte familiar como bajo. Los objetivos del estudio fueron caracterizar estrés, estilo parental y percepción de soporte familiar en padres de niños con TDAH, estableciendo relaciones entre estas variables. Así, 42 padres (padres y madres) respondieron al Inventario de Síntomas de Estrés para Adultos de Lipp (ISSL), Inventario de Estilos Parentales (IEP) e Inventario de Percepción de Apoyo Familiar (IPSF). Los resultados indican que las madres presentan más estrés que los padres; también hubo asociación del estrés de las madres con prácticas parentales negativas y baja percepción de soporte familiar. Otro hallazgo fue que cuanto mayor es la edad del niño peor el estilo parental que la familia presenta. Las nuevas investigaciones deben apoyar estos datos.

Postnatal maturation of the sternum in a Portuguese skeletal sample: a variable ossification process.

The timing of skeletal maturation is one of the common indicators used to estimate age at death of juvenile skeletal remains. Skeletal maturation of the sternum has received less attention than other anatomical locations, and there is a general lack of detailed information about the fusion timing in the dry sternum that can be used for the estimation of age. The objective of this study is to document the age variation in the fusion of the body sternebrae, and both clavicular and intercostal notches. A three stage scale scheme was used (unfused elements, partial, and complete fusion) to quantify fusion of primary and secondary ossification centres in a sample of 68 individuals of both sexes from the identified skeletal collection housed at the National Museum of Natural History and Science in Lisbon, Portugal. Analysis was performed only for the pooled sex sample due to small sample size. Wide age intervals were obtained for fusion stages at all of the sternal centres. Primary ossification centres start to fuse between 1 and 27 years of age, with sternebrae 3 and 4 completing their fusion first. Secondary ossification centres fuse between 5 to 25 years of age. Results reflect considerable variability among individuals in the maturation of the sternum.

Indirect evidence for biological mortality bias in growth from two temporo-spatially distant samples of children.

Biological mortality bias in growth is a challenge to the analysis and understanding of past populations. In this analysis, we address two interrelated aspects of the bias: its potential magnitude in terms of linear growth and the association between height and survivorship. A contemporary sample of 292 children, whose recumbent length was measured at autopsy in Cuyahoga County, USA, was used to quantify the magnitude of mortality bias. Differences between survivors and non-survivors were quantified using t-tests and Cohen's d for effect size. While survivors were consistently taller than non-survivors, the difference did not become significant until after 7 years of age. A historical sample of 656 girls, whose height and weight were measured at admission to a tuberculosis sanitarium, was used to examine the relationship between height, weight, and survivorship. The survivors and non-survivors were compared using t-tests and Cohen's d, and odds of survival were modeled with logistic regression. Surviving girls were consistently taller and heavier than non-surviving girls. However, while taller girls were more somewhat more likely to survive, survivorship was more strongly associated with heavier weight at admission. Taken together, these results suggest that while mortality bias in growth may exist, it may not be large enough to impact interpretations of past population growth patterns. It should be noted that this is the case only if mortality bias does not vary significantly between different populations and if it does not significantly affect dental development.

A Reappraisal of Developing Deciduous Tooth Length as an Estimate of Age in Human Immature Skeletal Remains.

This study provides an update on a quantitative method for immature age estimation based on postnatal deciduous mandibular tooth length. Two known sex and age skeletal collections from Western Europe were sampled (n = 97). Linear regression models for age estimated were calculated for each individual tooth, each sex, and sex combined sample using classical calibration. Prediction errors, residuals, and percentage of individuals whose real age fell within the 95% prediction interval were calculated. The teeth which develop earlier in life, the incisors and the first molar, showed the greatest precision, while the canine showed the least. This method has greater applicability to archeological skeletons or to children in developing countries than for use in North American or European forensic contexts. The method can be applied to incomplete or poorly preserved remains of unknown sex, particularly when dental radiographs are not an option or when teeth have been removed from the alveolus or crypt.

Are we using the appropriate reference samples to develop juvenile age estimation methods based on bone size? An exploration of growth differences between average children and those who become victims of homicide.

The population on which forensic juvenile skeletal age estimation methods are applied has not been critically considered. Previous research suggests that child victims of homicide tend to be from socioeconomically disadvantaged contexts, and that these contexts impair linear growth. This study investigates whether juvenile skeletal remains examined by forensic anthropologists are short for age compared to their normal healthy peers. Cadaver lengths were obtained from records of autopsies of 1256 individuals, aged birth to eighteen years at death, conducted between 2000 and 2015 in Australia, New Zealand, and the U.S. Growth status of the forensic population, represented by homicide victims, and general population, represented by accident victims, were compared using height for age Z-scores and independent sample t-tests. Cadaver lengths of the accident victims were compared to growth references using one sample t-tests to evaluate whether accident victims reflect the general population. Homicide victims are shorter for age than accident victims in samples from the U.S., but not in Australia and New Zealand. Accident victims are more representative of the general population in Australia and New Zealand. Different results in Australia and New Zealand as opposed to the U.S. may be linked to socioeconomic inequality. These results suggest that physical anthropologists should critically select reference samples when devising forensic juvenile skeletal age estimation methods. Children examined in forensic investigations may be short for age, and thus methods developed on normal healthy children may yield inaccurate results. A healthy reference population may not necessarily constitute an appropriate growth comparison for the forensic anthropology population.

Age estimation of immature human skeletal remains from the dimensions of the girdle bones in the postnatal period.

OBJECTIVES: This study provides classical calibration regression formulae for age estimation from the dimensions of unfused shoulder and pelvic girdle bones. MATERIALS AND METHODS: Age estimation models were derived from a sample of 160 known age and sex individuals (63 females and 97 males) aged birth to 12 years, selected from Portuguese and English skeletal collections. The sample was divided into two age groups at the age of 2 years, and formulae were obtained for the sexes separately and combined. RESULTS: Measurements of the pelvis provide more precise age estimates than the shoulder. In the younger age group, the height and width of the ilium, and the height of the glenoid yield the most precise age estimates. In the older age group, the length of the clavicle provides the most precise estimates, followed by measurements of the pubis and ischium. DISCUSSION: In the younger individuals (<2 years), age estimates based on measurements of the pelvic girdle seem to be as or more precise than those based on the length of long bones. In older individuals (≥2 years), estimates based on the measurements of the girdles are less precise than those based on the length of long bones. These age estimation formulae may be useful for fragmentary and incomplete material in archaeological and forensic contexts. The formulae are suitable for a variety of archeological populations living under adverse conditions. These conditions are similar to some "developing" countries, and hence the formulae may also be applicable to modern forensic remains from such environments.