Reproducibility of bone ages when performed by radiology registrars: an audit of Tanner and Whitehouse II versus Greulich and Pyle methods

Abstract

This audit analysed the Tanner and Whitehouse II twenty bone (TW2) method of bone age assessment which was used in our department, and compared it with the Greulich and Pyle (GP) method. 50 previous bone ages were independently re-calculated by each of three registrars using both techniques, with the time taken to perform each assessment being recorded. For each method the interobserver variation was analysed in terms of the spread of results. The intraobserver variation in TW2 was determined by comparing the bone age originally reported with that subsequently calculated on the same film by the same registrar. The average spread of results was 0.74 years for TW2 method, and 0.96 years for the GP method and this difference is not statistically significant at the 5% level. The average intraobserver variation to TW2 was 0.33 years, but with 95% confidence limits of -0.87 to +1.53 years. The average time taken was 7.9 min for TW2 and 1.4 min for GP assessments. It was concluded that the GP method gave similar reproducibility and was faster than the TW2 method. Following clinical discussion the routine departmental bone age assessment method was changed from the TW2 to the GP method.

Skeletal Age Determinations in Children of European and African Descent: Applicability of the Greulich and Pyle Standards

“…Lastly, bone determinations in this study were analyzed by two senior pediatric radiologists to minimize to some extent the subjectivity and intraobserver variability. The strong concordance in readings is a reflection of proficiency and confirms previous studies indicating that bone age estimations improve with clinical experience (17)(18)(19)(20).…”

The Use of Bone Age in Clinical Practice – Part 1

“…In most cases, the radiologists and pediatricians use the GP atlas, whereas some pediatric endocrinologists use the more finely scaled TW method [7]. Several studies have been published on the intra- and interobserver variance of BA [8,9,10,11]. King et al [8] provide an overview of many of these studies but it is difficult to draw any conclusions from their table because of conflicting results due to differing study designs, differing experience of the raters and differing measures of the interrater variability.…”

“…Several studies have been published on the intra- and interobserver variance of BA [8,9,10,11]. King et al [8] provide an overview of many of these studies but it is difficult to draw any conclusions from their table because of conflicting results due to differing study designs, differing experience of the raters and differing measures of the interrater variability. A recent study found a standard error of 0.55 years among the readings of a group of 5 pediatric endocrinologists and a standard error of 0.61 years among 7 radiologists.…”

Methods Used in Computer-Assisted Bone Age Assessment of Children

“…In a study conducted by King et al, 50 bone age assessments were performed by 3 evaluators using both the GP and TW2 techniques [7]. In the study, the error margin was determined as 0.74 years for TW2, and as 0.96 years for GP.…”

“…On the other hand, the GP method is far easier to implement due to its approach based mainly on comparisons of general appearance, which the human visual system is capable of performing quite rapidly. However, it is possible to state that the accuracy rate of this method rests more on the experience of the radiologist.In a study conducted by King et al, 50 bone age assessments were performed by 3 evaluators using both the GP and TW2 techniques [7]. In the study, the error margin was determined as 0.74 years for TW2, and as 0.96 years for GP.…”