Laurence Mainard-Simard

Bio: Laurence Mainard-Simard is an academic researcher. The author has contributed to research in topics: Bone age. The author has an hindex of 1, co-authored 1 publications receiving 8 citations.

Integrating Growth Variability of the Ilium, Fifth Lumbar Vertebra, and Clavicle with Multivariate Adaptive Regression Splines Models for Subadult Age Estimation.

Abstract: Subadult age estimation should rely on sampling and statistical protocols capturing development variability for more accurate age estimates. In this perspective, measurements were taken on the fifth lumbar vertebrae and/or clavicles of 534 French males and females aged 0-19 years and the ilia of 244 males and females aged 0-12 years. These variables were fitted in nonparametric multivariate adaptive regression splines (MARS) models with 95% prediction intervals (PIs) of age. The models were tested on two independent samples from Marseille and the Luis Lopes reference collection from Lisbon. Models using ilium width and module, maximum clavicle length, and lateral vertebral body heights were more than 92% accurate. Precision was lower for postpubertal individuals. Integrating punctual nonlinearities of the relationship between age and the variables and dynamic prediction intervals incorporated the normal increase in interindividual growth variability (heteroscedasticity of variance) with age for more biologically accurate predictions.

Age Estimation of Teenage Boys During Puberty.

Abstract: Background Age estimation of a minor whose identity is unknown must be accurate enough to respond to judicial requests. The main objective of this study is to accurately determine a teenager's age from simple and reproducible criteria. Samples and methods The first reference sample consists of 1720 measurements collected from 170 teenagers aged 11 to 16 years, over a period of 5 years. A second validation sample of 735 teenage boys aged 11 to 16 made it possible to verify the relevance of our estimates. The degree of maturation was determined using 4 pubertal stages: the stage below the age of puberty, the prepubescent stage, the parapubescent stage, and the pubescent stage.For each pubertal stage, an optimization of the values of the age was carried out in order to reduce the differences between the estimated and the actual age at the different age groups. Results The mean differences between estimated age and actual age from these values were -0.06 ± 0.91 years for the reference group and -0.49 ± 0.73 years for validation group. Conclusions Our method of age estimation is simpler and accurate. It could be used routinely in a forensic frame to respond to judicial requests.

Sexual dimorphism from third cervical vertebra (C3) on lateral cervical radiograph: A 2-dimensional geometric morphometric approach

Abstract: Sex identification is essential for the establishment of an accurate biological profile from skeletal remains in forensic anthropology. Conventional method using calipers is time-consuming and associated with a high margin of error especially in the case of highly fragmented skeletal remains. Geometric morphometric method is an approach which utilizes qualitative and quantitative description of biological forms according to geometric definitions of their shape. This study aimed to determine sexual dimorphism of third cervical (C3) vertebra on the lateral cervical radiograph by geometric morphometric method. Lateral cervical radiographs of 432 samples comprising of 262 males and 170 females of known individuals were retrieved retrospectively. The samples were adult Malaysian population aged from 20 to 60 years old. Eleven 2-dimensional (2D) landmarks were applied on the digitalized radiographs by TPSDig2 (Version 2.31) software. Geometric morphometric analysis was performed by MorphoJ software. Procrustes ANOVA showed that centroid size and shape are significantly different with p