Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/14320
Title: On the detection of seasonal variation in the onset of disease
Authors: GAO FEI
Keywords: onset of disease, seasonality, peak, angular regression, von Mises distribution, acute lymphoblastic leukaemia
Issue Date: 23-Nov-2004
Source: GAO FEI (2004-11-23). On the detection of seasonal variation in the onset of disease. ScholarBank@NUS Repository.
Abstract: Many studies have investigated the seasonality of onset of diseases over the calendar year, with a view to finding indications of their aetiology. This thesis studies statistical methodology for seasonality which can be summarised by a single peak or multiple peaks determined by patient characteristics or external influences. The circular, rather than linear, nature of the date of onset means that Normal distribution theory is not appropriate. Instead the von Mises distribution on a circle and angular regression methods are required. A computer program is developed to implement the methodology. The thesis re-examines, using angular methodology, summary data from published studies of acute lymphoblastic leukaemia (ALL). In addition, variation using individual dates of onset of ALL (in children and adults) from Singapore, Sweden and USA are examined. No clear picture emerges with respect to the seasonality of ALL although methodological difficulties with the published studies may obscure the overall pattern.
URI: http://scholarbank.nus.edu.sg/handle/10635/14320
Appears in Collections:Ph.D Theses (Open)

Show full item record
Files in This Item:
File Description SizeFormatAccess SettingsVersion 
thesis revised1.pdf1.18 MBAdobe PDF

OPEN

NoneView/Download

Page view(s)

227
checked on Dec 11, 2017

Download(s)

436
checked on Dec 11, 2017

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.