The Use of Roche, Wainer, and Thissen's Skeletal Maturity of the Knee.

The Roche, Wainer, and Thissen (RWT) knee method was designed to assess maturity in living individuals, but is infrequently cited in studies of skeletal measures for legal age thresholds or estimation of age-at-death for forensic cases. We implement the RWT method using R scripts and analyze its utility in establishing an age threshold of 18 years. We fit the RWT model and verify its accuracy in estimating skeletal age against results and known age data provided by RWT. We also found the transition distribution for full skeletal maturity. Agreement between the RWT method and our implementation was good, with a maximum deviation of 0.03 years. The modes of transition to full skeletal maturity are 18.37 and 17.16 years for males and females. The corresponding Bayes factors are 5.73 and 1.77, indicating that complete skeletal maturity of the knee does not provide conclusive evidence of attainment of 18 years of age.