A systematic review of the agreement between chronological age and skeletal age based on the Greulich and Pyle atlas.

OBJECTIVES: This systematic review examines the agreement between assessed skeletal age by the Greulich and Pyle atlas (GP skeletal age) and chronological age. METHODS: We searched electronic databases until January 2017 for studies reporting GP skeletal age and confirmed chronological age in healthy individuals aged 10-25 years. Results are presented as forest plots and meta-analyses (random-effects models). RESULTS: In separate meta-analyses for each age group and sex (14-18 years for girls, 14-19 years for boys), the pooled mean differences between GP skeletal age and chronological age varied from -0.52 years to 0.47 years. In individual studies, age group and sex-specific mean differences between GP skeletal age and chronological age rarely exceeded 1 year, but between-study heterogeneities were large in most age groups. Few studies examined mean chronological age and distribution for each GP skeletal age. One study of good methodological quality indicates that 95% prediction intervals for chronological age from given GP skeletal ages are typically around 4 years. CONCLUSIONS: There is still good correlation between GP skeletal age and mean chronological age in modern populations. However, the individual variation of development within a population and heterogeneities between studies are substantial. KEY POINTS: • The GP atlas still corresponds well with mean chronological age in modern populations. • The substantial variation within a population must be considered. • The heterogeneity between studies is relatively large and of unknown origin.

Age assessment by Demirjian's development stages of the third molar: a systematic review.

OBJECTIVES: Radiographic evaluation of the wisdom teeth (third molar) formation is a widely used age assessment method for adolescents and young adults. This systematic review examines evidence on the agreement between Demirjian's development stages of the third molar and chronological age. METHODS: We searched four databases up until May 2016 for studies reporting Demirjian's stages of third molar and confirmed chronological age of healthy individuals aged 10-25 years. Heterogeneity test of the included studies was performed. RESULTS: We included 21 studies from all continents except Australia, all published after 2005. The mean chronological age for Demirjian's stages varied considerably between studies. The results from most studies were affected by age mimicry bias. Only a few of the studies based their results on an unbiased age structure, which we argue as important to provide an adequate description of the method's ability to estimate age. CONCLUSION: Observed study variation in the timing of Demirjian's development stages for third molars has often been interpreted as differences between populations and ethnicities. However, we consider age mimicry to be a dominant bias in these studies. Hence, the scientific evidence is insufficient to conclude whether such differences exist. KEY POINTS: • There is significant heterogeneity between studies evaluating age assessment by Demirjian's third molar development. • Most of the studies were subject to the selection bias age mimicry which can be a source of heterogeneity. • Presence of age mimicry bias makes it impossible to compare and combine results. These biased studies should not be applied as reference studies for age assessment.

[Patient volume and quality in surgery for abdominal aortic aneurysm]. / Pasientvolum og kvalitet ved kirurgi for abdominale aortaaneurismer.

BACKGROUND Patient volume is assumed to affect quality, whereby complex procedures are best performed by those who perform them frequently. We have conducted a systematic review of the research on the association between patient volume and quality of vascular surgery. In this article we describe the outcomes for abdominal aortic aneurysm surgery.MATERIAL AND METHOD We undertook systematic searches in relevant databases. We searched for systematic reviews, and randomised and observational studies. The search was concluded in December 2015. We have summarised the results descriptively and assessed the overall quality of the evidence.RESULTS Forty-six observational studies fulfilled our inclusion criteria. We found a possible association for both hospital and surgeon volume. Higher patient volume may possibly be associated with lower 30-day mortality and lower hospital mortality for both open and endovascular surgery. Although the association appears to apply to both elective and acute hospitalisations, there is greater uncertainty with regard to the most ill patients. For hospital volume there may also be fewer complications for open and endovascular surgery, as well as for all surgery assessed as a whole. We considered the evidence base to be medium to very low quality.INTERPRETATION We found a possible correlation between patient volume and quality indicators such as mortality and complications. It may be advantageous to allocate planned procedures to institutions and surgeons with high volume, while this is less certain with regard to acute hospitalisations.