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修勻與小區域人口之研究 / A Study of smoothing methods for small area population金碩, Jin, Shuoh Unknown Date (has links)
由於誤差與人口數成反比,資料多寡影響統計分析的穩定性及可靠性,因此常用於推估大區域人口的方法,往往無法直接套用至縣市及其以下層級,尤其當小區域內部地理、社會或經濟的異質性偏高時,人口推估將更為棘手。本文以兩個面向對臺灣小區域人口進行探討:其一、臺灣人口結構漸趨老化,勢必牽動政府政策與資源分配,且臺灣各縣市的人口老化速度不一,有必要針對各地特性發展適當的小區域人口推估方法;其二、因為壽命延長,全球皆面臨長壽風險(Longevity Risk)的挑戰,包括政府退休金制度規劃、壽險保費釐定等,由於臺灣各地死亡率變化不盡相同,發展小區域死亡率模型也是迫切課題。
小區域推估面臨的問題大致可歸納為四個方向:「資料品質」、「地區人數」、「資料年數」與「推估年數」,資料品質有賴資料庫與制度的建立,關於後三個問題,本文引進修勻(Smoothing, Graduation)等方法來提高小區域推估及小區域死亡模型的穩定性。人口推估方面結合修勻與區塊拔靴法(Block Bootstrap),死亡率模型的建構則將修勻加入Lee-Carter與Age-Period-Cohort模型。由於小區域人口數較少,本文透過標準死亡比(Standard Mortality Ratio)及大區域與小區域間的連貫(Coherence),將大區域的訊息加入小區域,降低因為地區人數較少引起的震盪。
小區域推估通常可用的資料時間較短,未來推估結果的震盪也較大,本文針對需要過去幾年資料,以及未來可推估年數等因素進行研究,希冀結果可提供臺灣各地方政府的推估參考。研究發現,參考大區域訊息有穩定推估的效果,修勻有助於降低推估誤差;另外,在小區域推估中,如有過去十五年資料可獲得較可靠的推估結果,而未來推估年數盡量不超過二十年,若地區人數過少則建議合併其他區域增加資料量後再行推估;先經過修勻而得出的死亡率模型,其效果和較為複雜的連貫模型修正相當。 / The population size plays a very important role in statistical estimation, and it is difficult to derive a reliable estimation for small areas. The estimation is even more difficult if the geographic and social attributes within the small areas vary widely. However, although the population aging and longevity risk are common phenomenon in the world, the problem is not the same for different countries. The aim of this study is to explore the population projection and mortality models for small areas, with the consideration of the small area’s distinguishing characteristic.
The difficulties for small area population projection can be attributed into four directions: data quality, population size, number of base years, and projection horizon. The data quality is beyond the discussion of this study and the main focus shall be laid on the other three issues. The smoothing methods and coherent models will be applied to improve the stability and accuracy of small area estimation. In the study, the block bootstrap and the smoothing methods are combined to project the population to the small areas in Taiwan. Besides, the Lee-Cater and the age-period-cohort model are extended by the smoothing and coherent methods.
We found that the smoothing methods can reduce the fluctuation of estimation and projection in general, and the improvement is especially noticeable for areas with smaller population sizes. To obtain a reliable population projection for small areas, we suggest using at least fifteen-year of historical data for projection and a projection horizon not more than twenty years. Also, for developing mortality models for small areas, we found that the smoothing methods have similar effects than those methods using more complicated models, such as the coherent models.
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小區域死亡率模型與生命表編算 / A Study of Mortality Models and Life Table Construction of Small Areas鍾陳泰, Chung, Chen Tai Unknown Date (has links)
臺灣各縣市人口結構差異明顯,各縣市的人口出生、老化程度都不盡相同,而且在醫療分配及社會資源的使用也有很大的差異,因此各縣市應因應各地特性發展不同的小區域人口推估方法。由於樣本數與變異數成反比,人數較少者的死亡率(像是高齡人口)通常震盪較大,藉由適當的修勻(Graduation)調整,通常可降低年齡層間的死亡率震盪。然而,當縣市層級的人數太少時,只依賴修勻往往不足,多半會再參考人口較多的大母體之死亡率。例如:傳統的的貝氏修勻,使用Lee-Carter之類的參數死亡模型(Lee and Carter, 1992),或是透過小區域及大母體的死亡率比值(王信忠, 2012)。然而過去研究較少全面性的比較這些方法,尤其是用於人數較少(如:十萬人)的地區。
本文以探討小區域生命表及死亡率推估為目標,著眼於人數不多於五萬人,尋求較為適合臺灣及類似國家的死亡率編算方法。由於修勻或貝氏等方法可視為增加樣本數,本文將擴大樣本分為四種方式:「同地同時」、「同地異時」、「異地同時」、「異地異時」,亦即將死亡資料的整併分成是否限定於小區域,以及是否可擴及其他年度。本文藉由電腦模擬測試,提供在各種限制之下,最合適小區域生命表建構的準則。其中,本文假設大、小區域的死亡率間存有三種情境的關係:定值、遞增、V字型,藉由調整大小區域死亡率比值間的幅度,探討大母體及小區域間的差異對實務使用的影響。研究發現,Partial SMR方法是一個值得參考的方法,當大小區域死亡率類型接近時的效果不錯,甚至可用於人數小於一萬人,但若死亡率類型差異過大,修勻方法會有限制,使用時需格外謹慎。 / The population structure, life expectancy (and age-specific mortality rates), and the speed of population aging vary a lot in different county of Taiwan. Each county has its own policy planning according to the needs. However, the county level population is usually not enough to provide stable estimates, such as of the life expectancies and mortality rates at the county level. Thus, certain graduation methods are applied to stabilize these estimates. However, only a few studies focus on comparing different types of graduation methods, including traditional graduation methods, Bayesian methods, and parametric mortality models.
In this study, we separate the graduation methods into four types, according to if using only the small area data and if one year or multiple years of data are used, and explore which methods are appropriate to the areas with population fewer than 100,000. We use computer simulation to evaluate the graduation methods. We found that the Standard Mortality Ratio is promising when the mortality profiles of small and large populations are similar, and it is a feasible solution even for the areas with population fewer than 10,000. However, if the mortality profiles differ significantly, all graduation methods need to be applied with care.
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小區域死亡率模型的探討 / A Study of Small Area Mortality Models林志軒 Unknown Date (has links)
壽命延長及生育率下降使得人口老化日益明顯,成為全球多數國家在21世紀必須面對的議題,由於各區域人口老化的速度不同,必須根據各地特性而調整因應對策。其中研究死亡率變化為面對人口老化的必備課題,尤其是高齡族群的死亡率,這也是近年高齡死亡模型廣受重視的主因之一。因為樣本數與變異數成反比,人口較少的區域或是高齡人口,死亡率的觀察值通常會有較大震盪,為了降低震盪多半會經過修勻,以取得較為穩定的死亡率推估值(王信忠等人,2012)。此外,Li and Lee (2005)的Coherent Lee-Carter模型也是另一種可行方法,透過參考大區域的資訊降低小區域的估計誤差。
本文探討結合上述修勻、死亡率模型的可能,希冀能綜合兩者的優點,提高小區域死亡率推估的精確性。因為Coherent Lee-Carter模型的想法類似增加小區域的人數(加入大區域的人數),本文探討人口數與Lee-Carter模型參數估計值的關係,再以修勻調整大小區域的差異,透過電腦模擬及資料分析,驗證本文提出方法是否有效。其中,仿造王信忠等人的作法,假設小區域與大區域死亡率間的七種可能情境,以平均絕對百分誤差(Mean Absolute Percentage Error)為衡量標準,找出調整修勻、相關模型的方法。另外,本文也以臺灣縣市為研究區域,驗證本文方法的估計結果。研究發現適當地使用修勻方法,可降低小區域的死亡率估計值,其效果優於Coherent Lee-Carter模型。
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Factors influencing pregnancy outcome in high-risk patientsMudokwenyu-Rawdon, Christina 23 April 2001 (has links)
Abortion and severe pre-eclampsia/eclampsia remain the major causes of maternal
mortality in Zimbabwe. Based on this problem, factors associated with maternal
mortality due to abortion and severe pre-eclampsia/eclampsia were investigated to
improve pregnancy outcomes.
Cases and controls were selected from 4895 abortion and 318 severe preeclampsia/
eclampsia obstetric records to conduct a retrospective case-control study.
Significant risk factors identified for reducing maternal mortality due to postabortion
complications included the administration of oxytocic drugs and evacuations of the
uterus whilst anaemia and sepsis apparently reduced these women's chances of
survival. No significant factors could be identified which influenced maternal deaths
among women suffering from severe pre-eclampsia/eclampsia. Magnesium sulphate
was not routinely administered, as recommended internationally. In both groups,
cases apparently received better reported quantitative care than controls.
Recommendations based on this research report include improved midwifery
education and in-service training, regular audits of patients' records and changed
policies for managing these conditions more effectively in Zimbabwe. / Health Studies / D. Litt. et Phil. (Advanced Nursing Sciences)
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Incidence, mortality, comorbidities, and treatment of bullous pemphigoid in FinlandFörsti, A.-K. (Anna-Kaisa) 02 May 2017 (has links)
Abstract
Bullous pemphigoid (BP) is an autoimmune skin disease predominantly found in elderly people, which causes blistering of the skin and severe itching. The incidence of BP reported by previous studies has varied greatly between 0.05 and 42.8 per 1 million persons per year. Higher incidences have been reported in Western Europe and the USA, while countries around the Mediterranean have reported lower rates. However, the epidemiology of BP has not previously been studied in any Scandinavian country. The one-year mortality of BP is highly variable with estimates between 11% and 41% worldwide. As for comorbidities, the previous studies have shown that BP is associated with neurological disorders.
The aim of this study was to investigate the incidence and mortality of BP in Finland, to assess the treatments used for BP, and the potential contribution of systemic glucocorticoid treatment to the high mortality rate found in BP patients. A further aim was to obtain more specific information about the neurological diseases associated with BP, and to clarify the less studied association with psychiatric disorders. For these purposes, we collected the records of all immunologically confirmed BP patients diagnosed in the Oulu University Hospital between 1985 and 2012, and, for a sub-study III, data for all patients diagnosed with BP in Finnish hospitals between 1987 and 2013.
We found that the incidence of BP in Northern Finland has increased over the past two decades to approximately 27 new BP cases per 1 million persons per year. The one-year mortality of BP patients is 17%, and the standardized mortality ratio (SMR) is 7.6. Common comorbidities found in the sample of BP patients were: cardiovascular diseases (76%), neurodegenerative diseases (41%), skin conditions other than BP (37%) and type 2 diabetes (23%). Many neurodegenerative diseases of the central nervous system were associated with BP, as were many psychiatric disorders. The association was strongest between multiple sclerosis (MS) and BP, with MS patients having almost a 6-fold higher risk of BP than controls.
The present study reports for the first time the incidence and mortality of BP in Finland, and provides new information about the association between BP and neurological and psychiatric disorders. / Tiivistelmä
Rakkulainen pemfigoidi (josta jatkossa käytetään nimitystä pemfigoidi) on autoimmuunisairaus, joka esiintyy yleensä iäkkäillä, ja aiheuttaa ihon rakkulointia ja hankalaa kutinaa. Aiemmissa tutkimuksissa pemfigoidin ilmaantuvuus on vaihdellut 0,05:sta 42,8:aan tapaukseen miljoonaa ihmistä kohden vuodessa. Ilmaantuvuuden on havaittu olevan korkeampi Länsi-Euroopassa, kun taas Välimeren ympäristössä ilmaantuvuus on matalampi. Pemfigoidia sairastavien kuolleisuus vuoden kuluessa diagnoosista vaihtelee noin 11-41%:n välillä. Aiemmat tutkimukset ovat myös osoittaneet, että pemfigoidi liittyy neurologisiin sairauksiin. Pemfigoidin epidemiologiaa ei ole kuitenkaan tutkittu Suomessa tai muissa Pohjoismaissa.
Tämän tutkimuksen tarkoituksena oli selvittää pemfigoidin ilmaantuvuus ja kuolleisuus Suomessa, tutkia sen hoitoon käytettyjä lääkkeitä sekä arvioida systeemisen glukokortikoidihoidon osuutta korkeaan kuolleisuuteen. Lisäksi tavoitteena oli saada yksityiskohtaista tietoa pemfigoidiin liittyvistä neurologisista sairauksista ja selvittää lisää aiemmissa tutkimuksissa ristiriitaiseksi jäänyttä yhteyttä psykiatrisiin sairauksiin. Tätä varten keräsimme tiedot kaikista Oulun yliopistollisessa sairaalassa diagnosoiduista, immunologisesti varmennetuista pemfigoiditapauksista vuosilta 1985-2012. Kolmannessa osatyössä käytimme kansallista aineistoa, joka sisälsi kaikkialla Suomessa diagnosoidut pemfigoidia sairastavat potilaat vuosilta 1987-2013.
Pemfigoidin ilmaantuvuus kasvoi seuranta-aikana ollen nykyisin Pohjois-Suomessa noin 27 tapausta miljoonaa ihmistä kohden vuodessa. Kuolleisuus vuoden kuluessa diagnoosista oli 17% ja vakioitu kuolleisuussuhde (standardized mortality ratio) 7,6. Yleisiä oheissairauksia pemfigoidia sairastavilla olivat sydän- ja verisuonisairaudet (76%), neurodegeneratiiviset sairaudet (41%), muut ihosairaudet (37%) sekä tyypin 2 diabetes (23%). Tutkimuksessa todettiin, että monet neurogeneratiiviset sairaudet ja monet psykiatriset sairaudet liittyvät pemfigoidiin. Yhteys oli vahvin pesäkekovettumataudin (MS-tauti) ja pemfigoidin välillä, ja MS-tautia sairastavilla riski sairastua pemfigoidiin oli lähes 6-kertainen verrattuna kontrollipotilaisiin.
Tämä tutkimus on ensimmäinen, joka raportoi pemfigoidin ilmaantuvuuden ja kuolleisuuden Suomessa. Tutkimus antaa lisäksi uutta tietoa pemfigoidin yhteydestä neurologisiin ja psykiatrisiin sairauksiin.
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Estimation de la mortalité attendue à long terme des maladies chroniques : une comparaison de différentes méthodes d’analyseRoy-Brunelle, Raphaël 02 1900 (has links)
Il est rarement possible de connaitre avec précision la mortalité à long terme associée à une condition médicale. Cependant, l’estimation de cette mortalité est primordiale dans certains domaines tels l’assurance-vie et l’expertise médicale. La méthode du Relative Risk (RR) constant, qui est la plus utilisée, comporte plusieurs failles, permettant seulement de faire des estimations grossières et conservatrices de cette mortalité.
Nous avons donc comparé deux autres méthodes d’estimation de la mortalité, soit Excess Death Rate (EDR) constant et Proportional Life Expectancy (PLE). Nous avons analysé la mortalité à long terme de plusieurs maladies chroniques, entre autres le cancer et les maladies cardiovasculaires, et avons comparé ces résultats avec ceux que nous donnaient les différentes méthodes d’estimation. Nous avons ainsi pu déterminer la meilleure méthode.
Nos résultats indiquent que les méthodes EDR constant et PLE sont supérieures au RR constant dans l’estimation de la mortalité. Aussi, plus l’estimation de la survie se fait à long terme, plus l’EDR constant et la PLE donnent de meilleurs résultats. Finalement, l’âge ou le type de conditions médicales analysées ne semblent pas avoir un impact déterminant lorsque l’on choisit d’utiliser l’une des trois méthodes.
Les méthodes de l’EDR constant et la PLE devraient être préconisées dans l’analyse de la mortalité lors de la sélection des risques en médecine d’assurance ou lors d’évaluation de l’espérance de vie pour une expertise médicale. / Long term mortality associated to medical conditions is rarely known with accuracy. Despite this, mortality assessment is essential in certain field of activity, such as life insurance and medical expertise. Constant Relative Risk (RR) methodology is the most used method although often leading to superficial and conservative estimations.
We then decided to compare two mortality estimation methods, the constant Excess Death Rate (EDR) and the Proportional Life Expectancy (PLE). We analyzed long term mortality of several chronic medical conditions, such as cancers and coronary artery diseases, and we compared those results with those from the three distinct estimation methods. Thus, we were able to determine which methodology is the most accurate.
Our results show that constant EDR and PLE are superior to constant RR to better estimate the mortality. The longer the follow-up is, the better those methods are. Finally, factors like age and the kind of the medical condition seem not to have an important impact when it comes to identify the most suitable method.
Constant EDR and PLE should be recommended for mortality assessment in medical insurance underwriting and for life expectancy evaluation in medical expertise.
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