Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Statistical methods for detecting and comparing periodic data and their application to the nycthemeral rhythm of bodily harm: A population based study. | Stroebel et al. Journal of Circadian Rhythms 2010 8 10 http content 8 1 10 JOURNAL OF CIRCADIAN RHYTHMS RESEARCH Open Access Statistical methods for detecting and comparing periodic data and their application to the nycthemeral rhythm of bodily harm A population based study 1 1 12 1 13 Armin M Stroebel Matthias Bergner Udo Reulbach Teresa Biermann Teja W Groemer Ingo Klein Johannes Kornhuber1 Abstract Background Animals including humans exhibit a variety of biological rhythms. This article describes a method for the detection and simultaneous comparison of multiple nycthemeral rhythms. Methods A statistical method for detecting periodic patterns in time-related data via harmonic regression is described. The method is particularly capable of detecting nycthemeral rhythms in medical data. Additionally a method for simultaneously comparing two or more periodic patterns is described which derives from the analysis of variance ANOVA . This method statistically confirms or rejects equality of periodic patterns. Mathematical descriptions of the detecting method and the comparing method are displayed. Results Nycthemeral rhythms of incidents of bodily harm in Middle Franconia are analyzed in order to demonstrate both methods. Every day of the week showed a significant nycthemeral rhythm of bodily harm. These seven patterns of the week were compared to each other revealing only two different nycthemeral rhythms one for Friday and Saturday and one for the other weekdays. Background Analysis of biological activities that fluctuate throughout the day is common in various fields of medicine. Blood pressure and heart rate as well as the occurrence of acute cardiovascular disease are subject to a twenty-four hour rhythm also referred to as circadian or nycthem-eral rhythm 1 2 . This rhythm is also present in episodes of dyspnoea in nocturnal asthma 3 intraocular pressure 4 5 and hormonal pulses 6-8 . Nycthemeral fluctuations in neurotransmitters and .
