title: Measuring the intercondylar shelf angle using radiographs: intra- and inter-observer error tests of reliability.
abstract: This study presents a test of intra- and inter-observer measurement error rates of the intercondylar shelf angle of the distal femur, as measured on lateral radiographs. This measurement is the central element of a method to determine racial affiliation from the distal femur. Four observers independently radiographed a set of 33 complete and partial femora from collections housed at the Joint POW/MIA Accounting Command, Central Identification Laboratory. Each observer then measured the intercondylar shelf angles in each radiograph, following the original method's guidelines. A supplementary inter-observer error test was conducted by four additional observers on one set of radiographs. Statistically significant differences were found for both intra- and inter-observer error based on the results of Student's t-tests, paired samples t-tests, and ANOVA analyses. The results of this study indicate that further experimentation should be undertaken in order to develop refined measurement techniques that may help improve standardization and reduce the observer error rates.
authors.affiliation: Joint POW/MIA Accounting Command-Central Identification Laboratory (JPAC-CIL), Hickam AFB, HI 96853-5530, USA. greg.berg@ds.jpac.pacom.mil
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Berg
authors.forename: Sabrina C
authors.initials: SC
authors.lastname: Ta'ala
authors.forename: Elias J
authors.initials: EJ
authors.lastname: Kontanis
authors.forename: Sardiaa S
authors.initials: SS
authors.lastname: Leney
mesh_terms: D000704:Analysis of Variance; D005269:Femur / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D018732:Forensic Anthropology / Q000379:methods*; D006801:Humans; D015588:Observer Variation; D044469:Racial Groups; D011859:Radiography; D015203:Reproducibility of Results