Stature estimation and sex determination from contemporary Northeastern Thai clavicles using discriminant function and linear regression analyses

Abstract

Background

Reliable methods for stature estimation and sex determination are still needed for anthropologists to identify other skeletal remains for applying in forensic cases when the skull or pelvis disappears or is severely damaged. The clavicle is known to have high sexual dimorphism because of its anatomical features including size and shape. High variability of clavicle has significant forensic application in many populations except the modern Northeastern Thais. This study aimed to develop the discriminant function analysis to estimate stature and sex dimorphism from dry clavicles in exploring a potential method for Thai forensic anthropology.

Materials and method

Four hundred dry clavicles (200 males, 200 females) identified for sex and height before body donation were measured for six standardized parameters including maximum length of clavicle (MaxL), anterior-posterior width at the acromion end surface (APA), anterior-posterior width at the sternal end surface (APS), superior-inferior width at the acromion end surface (SIA), superior-inferior width at the sternal end surface (SIS), and circumference at the mid-shaft of clavicle (CirMid), respectively. The discriminant function and regression analyses were used for sex determination and stature estimation.

Results

All parameters showed significant difference of sexual dimorphism with greater in male dimensions compared to those of females (p < 0.01). For sex determination using univariate analysis, the most accuracy rate was of MaxL (83.5 %). In stepwise discriminant function analysis, the four parameters of MaxL, APS, SIS, and CirMid on the right side could enhance the accuracy rate up to 88.5 %. The highest correlation of stature estimation was observed in the combined-sex analysis (r = 0.73, R² = 0.54, SEE = 5.78 cm) by using only right MaxL and CirMid parameters.

Conclusion

Multi-variable discriminant functions provide more reliability in sex determination while the combined-sex equations is the most effective method to estimate stature for contemporary Northeastern Thais. This novel method can be used to apply in the forensic anthropological analysis for Thai clavicle remain.