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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Prognostic factors associated with disease progression in parkinson's disease

Ferguson, Leslie Wayne 27 February 2006
This thesis examined the factors correlated with rapid and benign progression of disease in a group of 1452 Parkinsons disease (PD) patients. The data were collected in a movement disorders clinic at the Royal University Hospital, University of Saskatchewan run by Dr. Alex Rajput and Dr. Ali Rajput. This data is a clinical dataset of PD patients collected from 1970 through to February, 2005. This was a retrospective cases-only study, with anticipated analytical follow-up if any correlations were detected between progression type of PD and the many independent variables available in the dataset. <p>Rapid progression was defined as those subjects who reached Hoehn and Yahr stage 3 within three years or H&Y stage 4 or 5 within five years. Subjects who remained in Hoehn and Yahr stage 1 or 2, ten years after onset of disease, were defined as having benign progression. The study analyzed demographic and clinical findings at first visit to this clinic associated with rapid and benign progression of PD. <p> Analysis revealed that, at first clinic visit, benign progression was positively associated with disease duration (OR=1.41; 95% CI 1.27, 1.57), male sex (OR=3.23; 95% CI 1.70, 6.16), and current smoking habit (OR=2.33; 95% CI 0.67, 8.11). Benign progression was negatively associated with older age of onset (OR=0.36; 95% CI 0.25, 0.50), past history of smoking (OR=0.46; 95% CI 0.24, 0.89), current or past use of levodopa (OR=0.45; 95% CI 0.21, 0.98), and mild to severe rigidity (OR=0.43; 95% CI 0.23, 0.80). <p>Analysis also revealed that, at first clinic visit, rapid progression was positively associated with older age of onset (OR=2.45; 95% CI 1.80, 3.33) and mild to severe rigidity (OR=1.73; 95% CI 1.02, 2.94). Rapid progression was negatively associated with disease duration (OR=0.52; 95% CI 0.44, 0.62), male sex (OR=0.58; CI 0.35, 0.95), and mild to severe resting tremor (OR=0.47; CI 0.28, 0.77). <p>The results of this study indicate that age of onset, disease duration, male sex, and rigidity are good potential predictors of disease progression in PD because they have opposite associations with rapid and benign progression. History of levodopa use was negatively associated with benign progression and as such may be good indicator of non-benign progression. Although previous studies found no predictive value for smoking history, the current study reported a unique association between smoking history and benign progression. Past smoking history was negatively associated with benign progression. While there was a positive association with current smoking history, the result was not statistically significant. Resting tremor was negatively associated with rapid progression and as such may be a good indicator of non-rapid progression. <p> Disease characteristics collected at first clinic visit are useful in predicting the course of progression of PD. With more rapid progression of PD closer and more frequent follow-up of patients may be necessary.
2

Prognostic factors associated with disease progression in parkinson's disease

Ferguson, Leslie Wayne 27 February 2006 (has links)
This thesis examined the factors correlated with rapid and benign progression of disease in a group of 1452 Parkinsons disease (PD) patients. The data were collected in a movement disorders clinic at the Royal University Hospital, University of Saskatchewan run by Dr. Alex Rajput and Dr. Ali Rajput. This data is a clinical dataset of PD patients collected from 1970 through to February, 2005. This was a retrospective cases-only study, with anticipated analytical follow-up if any correlations were detected between progression type of PD and the many independent variables available in the dataset. <p>Rapid progression was defined as those subjects who reached Hoehn and Yahr stage 3 within three years or H&Y stage 4 or 5 within five years. Subjects who remained in Hoehn and Yahr stage 1 or 2, ten years after onset of disease, were defined as having benign progression. The study analyzed demographic and clinical findings at first visit to this clinic associated with rapid and benign progression of PD. <p> Analysis revealed that, at first clinic visit, benign progression was positively associated with disease duration (OR=1.41; 95% CI 1.27, 1.57), male sex (OR=3.23; 95% CI 1.70, 6.16), and current smoking habit (OR=2.33; 95% CI 0.67, 8.11). Benign progression was negatively associated with older age of onset (OR=0.36; 95% CI 0.25, 0.50), past history of smoking (OR=0.46; 95% CI 0.24, 0.89), current or past use of levodopa (OR=0.45; 95% CI 0.21, 0.98), and mild to severe rigidity (OR=0.43; 95% CI 0.23, 0.80). <p>Analysis also revealed that, at first clinic visit, rapid progression was positively associated with older age of onset (OR=2.45; 95% CI 1.80, 3.33) and mild to severe rigidity (OR=1.73; 95% CI 1.02, 2.94). Rapid progression was negatively associated with disease duration (OR=0.52; 95% CI 0.44, 0.62), male sex (OR=0.58; CI 0.35, 0.95), and mild to severe resting tremor (OR=0.47; CI 0.28, 0.77). <p>The results of this study indicate that age of onset, disease duration, male sex, and rigidity are good potential predictors of disease progression in PD because they have opposite associations with rapid and benign progression. History of levodopa use was negatively associated with benign progression and as such may be good indicator of non-benign progression. Although previous studies found no predictive value for smoking history, the current study reported a unique association between smoking history and benign progression. Past smoking history was negatively associated with benign progression. While there was a positive association with current smoking history, the result was not statistically significant. Resting tremor was negatively associated with rapid progression and as such may be a good indicator of non-rapid progression. <p> Disease characteristics collected at first clinic visit are useful in predicting the course of progression of PD. With more rapid progression of PD closer and more frequent follow-up of patients may be necessary.
3

Is It Attachment Style or Socio-Demography: Singlehood in a Representative Sample

Katja, Petrowski, Schurig, Susan, Schmutzer, Gabriele, Brähler, Elmar, Stöbel-Richter, Yve 15 August 2022 (has links)
Since the percentage of single adults is steadily increasing, the reasons for this development have become a matter of growing interest. Hereby, an individual’s attachment style may have a connection to the partnership status. In the following analysis, attachment style, gender, age, education, and income were compared in regard to the partnership status. Furthermore, an analysis of variance was computed to compare the attachment style within different groups. In 2012, a sample of 1,676 representative participants was used. The participants were aged 18 to 60 (M = 41.0, SD = 12.3); 54% of the sample were female, and 40% were single. Attachment-related attitudes were assessed with the German version of the adult attachment scale (AAS). Single adult males did not show a more anxious attachment style than single adult females or females in relationships. Younger, i.e., 18 to 30 years old, paired individuals showed greater attachment anxiety than single individuals, whereby single individuals between the ages of 31 to 45 showed greater attachment anxiety than individuals in relationships. In addition, single individuals more frequently had obtained their high school diploma in contrast to individuals in relationships. Concerning attachment style, the individuals who had not completed their high school diploma showed less faith in others independent of singlehood or being in a relationship. Concerning age, older single individuals, i.e., 46 to 60 years, felt less comfortable in respect to closeness and showed less faith in others compared to paired individuals. Logistic regression showed that individuals were not single if they did not mind depending on others, showed high attachment anxiety, were older, and had lower education. An income below € 2000/month was linked to a nearly 13-fold increase of likelihood of being single. In sum, the attachment style had a differential age-dependent association to singlehood versus being in a relationship. Education played also a role, exclusively concerning faith in others.
4

Spatial sampling and prediction

Schelin, Lina January 2012 (has links)
This thesis discusses two aspects of spatial statistics: sampling and prediction. In spatial statistics, we observe some phenomena in space. Space is typically of two or three dimensions, but can be of higher dimension. Questions in mind could be; What is the total amount of gold in a gold-mine? How much precipitation could we expect in a specific unobserved location? What is the total tree volume in a forest area? In spatial sampling the aim is to estimate global quantities, such as population totals, based on samples of locations (papers III and IV). In spatial prediction the aim is to estimate local quantities, such as the value at a single unobserved location, with a measure of uncertainty (papers I, II and V). In papers III and IV, we propose sampling designs for selecting representative probability samples in presence of auxiliary variables. If the phenomena under study have clear trends in the auxiliary space, estimation of population quantities can be improved by using representative samples. Such samples also enable estimation of population quantities in subspaces and are especially needed for multi-purpose surveys, when several target variables are of interest. In papers I and II, the objective is to construct valid prediction intervals for the value at a new location, given observed data. Prediction intervals typically rely on the kriging predictor having a Gaussian distribution. In paper I, we show that the distribution of the kriging predictor can be far from Gaussian, even asymptotically. This motivated us to propose a semiparametric method that does not require distributional assumptions. Prediction intervals are constructed from the plug-in ordinary kriging predictor. In paper V, we consider prediction in the presence of left-censoring, where observations falling below a minimum detection limit are not fully recorded. We review existing methods and propose a semi-naive method. The semi-naive method is compared to one model-based method and two naive methods, all based on variants of the kriging predictor.
5

Socio-demography and Attachment-styles of Married and Cohabiting Individuals in a Representative Sample

Petrowski, Katja, Schurig, Susan, Schmutzer, Gabriele, Brähler, Elmar 10 October 2017 (has links) (PDF)
Cohabitation is becoming more prevalent in western society so that up to 7.5 million cohabiting couples were reported in the USA for the year 2010. The present study investigated whether the cohabitants’ attachment style might be one of the reasons for cohabitation gaining such popularity. Attachment styles as well as socio-demographic variables were compared in regard to the partnership status. A sample of 1,002 participants aged 18 to 60 were used as a representative sample (M = 43.5, SD = 10.9), of which 54% were female and 82% were married. The cohabitants were younger, more highly educated, and less frequently affiliated with a church. The cohabitants were more anxious-attached, especially those of a younger age. A one-point increase in value on the AAS anxiety scale almost doubled the possibility of cohabitation. Most of the variance can be explained by socio-demographic variables. However, based on these representative data, and after controlling for socio-demographic variables, attachment anxiety is still connected to cohabitation. The diverse results in the literature may be explained by differences in the socio-demographic characteristics of the sample.
6

Socio-demography and Attachment-styles of Married and Cohabiting Individuals in a Representative Sample

Petrowski, Katja, Schurig, Susan, Schmutzer, Gabriele, Brähler, Elmar 10 October 2017 (has links)
Cohabitation is becoming more prevalent in western society so that up to 7.5 million cohabiting couples were reported in the USA for the year 2010. The present study investigated whether the cohabitants’ attachment style might be one of the reasons for cohabitation gaining such popularity. Attachment styles as well as socio-demographic variables were compared in regard to the partnership status. A sample of 1,002 participants aged 18 to 60 were used as a representative sample (M = 43.5, SD = 10.9), of which 54% were female and 82% were married. The cohabitants were younger, more highly educated, and less frequently affiliated with a church. The cohabitants were more anxious-attached, especially those of a younger age. A one-point increase in value on the AAS anxiety scale almost doubled the possibility of cohabitation. Most of the variance can be explained by socio-demographic variables. However, based on these representative data, and after controlling for socio-demographic variables, attachment anxiety is still connected to cohabitation. The diverse results in the literature may be explained by differences in the socio-demographic characteristics of the sample.
7

Measuring long-term effects of a school improvement initiative

Svärdh, Joakim January 2013 (has links)
There is a growing demand for studies applying quantitative methods to large-scale data sets for the purpose of evaluating the effects of educational reforms (UVK, 2010). In this thesis the statistical method, Propensity Score Analysis (PSA), is presented and explored in the evaluating context of an extensive educational initiative within science and technology education; the Science and Technology for All-program (NTA). The research question put forward reads; under what conditions are PSA-analyses a useful method when measuring the effects from a school improvement initiative in S &amp; T? The study considers the use of PSA when looking for long-term effects that could be measured, what to take into consideration to be able to measure this, and how this could be done. The baseline references (outcome variables) used in order to measure/evaluate the long-term effects from the studied program is students’ achievements in the national test (score and grades) and their grades in year 9. Some findings revealed regarding the object of study (long-term effects from using NTA) are also presented. The PSA method is found to be a useful tool that makes it possible to create artificial control groups when experimental studies are impossible or inappropriate; which is often the case in school education research. The method opens up for making use of the rich source of registry data gathered by authorities. PSA proves reliable and relatively insensitive to the effects of covariates and heterogeneous effecter if the number of samples is large enough. The use of PSA (or other statistical methods) also makes it possible to measure outcomes several years after treatment. There are issues of concern when using PSA. One is the obvious demand for organized collection of measurement data. Another issue of concern is the choice of outcome variables. In this study the chosen outcome variables (pupils’ score and grading in national tests and grades in year 9) open up for discussions regarding aspects that might not be reflected/measured in national tests and/or teachers’ grading. Findings regarding the long-term effects from using NTA) show significantly positive effects in physics on test scores (average increase 16.5%) and test grades, but not in biology and chemistry. In this study no significant effects are found for course grades. PSA approach has proved to be a reliable method. There is however a limitation in terms of the method's ability to capture more subtle aspects of learning. A combination of quantitative and qualitative approach when studying long-term effects from educational intervention is therefore suggested. / <p>QC 20131120</p>
8

Distribution of and relationship between medically classified weight and self-perceived body size across sexual orientation: An Add Health analysis

Strauss, Ashley J. 28 November 2016 (has links)
No description available.
9

The Influence of multiple determinants on health related quality of life and mental health of a Spanish representative sample of adolescents and youths

Villalonga Olives, Ester 30 November 2011 (has links)
The thesis is based on the Kidscreen Follow-up study. A representative sample of Spanish adolescents and youths and one of their parents were assessed twice (3 years apart) to evaluate adolescents and youths health related quality of life and mental health. The specific objectives of this thesis were to assess the effect of life events, and family and social variables (parents' mental health and home life) on three different health related outcomes: heath related quality of life, mental health, and psychosomatic complaints of adolescents and youths. The Coddington Life Events Scales were adapted into Spanish using the translation and back-translation process. Multiple linear regression and structural equation modelling were used to analyze the effect of the determinants selected. Life events and parents' mental health acted as risk factors for the outcomes selected, specially on mental health outcomes, whereas family factors like the relation with family members in home life were protective factors. Social factors inside the family should be promoted and reinforced to protect adolescents and youths from the effect of risk factors. / Aquesta tesi és part de l'estudi KIDSCREEN Follow-up. Utilitzant una mostra representativa d'adolescents i joves de l'estat espanyol, es van mesurar diferents aspectes relacionats amb la salut, avaluant la mostra dues vegades (amb una separació de 3 anys). Concretament, l'objectiu de la tesi va ser avaluar l'efecte dels aconteixements vitals i factors familiars i socials (salut mental dels pares i vida familiar) en tres resultats en salut: la qualitat de vida relacionada amb la salut, la salut mental i els problemes psicosomàtics dels adolescents i joves. Per això, es va adaptar l'escala Coddington Life Events Scales seguint la metodologia de traducció-retrotraducció. Es van utilizar models de regressió i models d'equacions estructurals per analitzar l'efecte dels determinants en salut. Els aconteixements vitals i la salut mental dels pares van ser dos factors de risc importants, especialment en la salut mental dels adolescents i joves. Per altra banda, les variables familiars com la relació dels membres de la família van actuar com a factors protectors. La cohesió dels membres de la família s'ha de promoure per tal de protegir els adolescents i joves de l'efecte de factors de risc.

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