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A comparison of longitudinal statistical methods in studies of pulmonary function declineDimich-Ward, Helen D. 05 1900 (has links)
Three longitudinal pulmonary function data sets were analyzed by several statistical methods for the purposes of:
1) determining to what degree the conclusions of an analysis for a given data set are method dependent;
2) assessing the properties of each method across the different data sets;
3) studying the correlates of FEV₁ decline including physical, behavioral, and respiratory factors, as well as city of residence and type of work.
4) assessing the appropriateness of modelling the standard linear relationship of FEV₁ with time and providing alternative approaches;
5) describing longitudinal change in various lung function variables, apart from FEV₁.
The three data sets were comprised of (1) yearly data on 141 veterans with mild chronic bronchitis, taken at three Canadian centres, for a maximum of 23 years of follow-up; their mean age at the start of the study was 49 years (s.d.=9) and only 10.6% were nonsmokers during the follow-up; (2) retrospective data on 384 coal workers categorized into four groups according to vital status (dead or alive) and smoking behavior, with irregular follow-up intervals ranging from 2 to 12 measurements per individual over a period of 9 to 30 years; (3) a relatively balanced data set on 269 grain workers and a control group of 58 civic workers, which consisted of 3 to 4 measurements taken over an average follow-up of 9 years. Their mean age at first measurement was 37 years (s.d.=10) and 53.2% of the subjects did not smoke.
A review of the pulmonary and statistical literature was carried out to identify methods of analysis which had been applied to calculate annual change in FEV₁. Five methods chosen for the data analyses were variants of ordinary least squares approaches. The other four methods were based on the use of transformations, weighted least squares, or covariance structure models using generalized least squares approaches.
For the coal workers, the groups that were alive at the time of ascertainment had significantly smaller average FEV₁ declines than the deceased groups. Post-retirement decline in FEV₁ was shown by one statistical method to significantly increase for coal workers who smoked, while a significant decrease was observed for nonsmokers. Veterans from Winnipeg consistently showed the lowest decline estimates in comparison to Halifax and Toronto; recorded air pollution measurements were found to be the lowest for Winnipeg, while no significant differences in smoking behavior were found between the veterans of each city. The data set of grain workers proved most ameniable to all the different analytical techniques, which were consistent in showing no significant differences in FEV₁ decline between the grain and civic workers groups and the lowest magnitude of FEV₁ decline.
It was shown that quadratic and allometric analyses provided additional information to the linear description of FEV₁ decline, particularly for the study of pulmonary decline among older or exposed populations over an extended period of time. Whether the various initial lung function variables were each predictive of later decline was dependent on whether absolute or percentage decline was evaluated. The pattern of change in these lung function measures over time showed group differences suggestive of different physiological responses.
Although estimates of FEV₁ decline were similar between the various methods, the magnitude and relative order of the different groups and the statistical significance of the observed inter-group comparisons were method-dependent No single method was optimal for analysis of all three data sets. The reliance on only one model, and one type of lung function measurement to describe the data, as is commonly found in the pulmonary literature, could lead to a false interpretation of the result Thus a comparative approach, using more than one justifiable model for analysis is recommended, especially in the usual circumstances where missing data or irregular follow-up times create imbalance in the longitudinal data set. / Graduate and Postdoctoral Studies / Graduate
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Oxygen uptake and lung compliance in murine pulmonary infections /Korotzer, Terry Ira January 1975 (has links)
No description available.
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Interval training in females : changes in pulmonary function and diffusion capacity /Jackson, Thomas Goodlow January 1976 (has links)
No description available.
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Forced vital capacity maneuvers in dogs : a comparison of two forcing systems /Mihalko, Paul J. January 1979 (has links)
No description available.
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RESPIRATORY KINEMATICS IN CLASSICAL SINGERS.Watson, Peter J. January 1983 (has links)
No description available.
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Effects of upper body resistance training on pulmonary function in sedentary male smokers27 October 2008 (has links)
M.Phil. / The effects of an upper body resistance training (UBRT) programme on spirometry values are not well documented or researched. The sparse number of studies that have focussed on this topic have generated inconclusive data on the effects of UBRT on pulmonary function. The present investigation made use of an eight-week UBRT programme in order to evaluate whether this would yield significant changes with regards to the following spirometry values: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), 25% of forced expiratory flow (FEF-25), 50% of forced expiratory flow (FEF-50), 75% of forced expiratory flow (FEF-75), FEV1/FVC ratio, peak expiratory flow (PEF), peak inspiratory flow (PIF), vital capacity (VC), inspiratory vital capacity (IVC), FEV1/VC ratio, expiratory reserve volume (ERV) and minute ventilation (VE). The study made use of 36 sedentary but healthy male smokers (mean age: 33 years and 6 months), who were assigned into either a non-exercising control (CG) (n = 18) or exercising experimental (EG) (n = 18) group. A seven-day smoking analysis was recorded for both the EG and CG before and after the eight-week experimental period in order to control for any changes that might have occurred with regards to their smoking behaviour in an attempt to account for any changes in pulmonary function. The EG group were assigned to exercise for eight-weeks three times weekly on non-consecutive days using an UBRT programme. Their spirometry values were assessed at the commencement of and subsequent to the eight-week period. The EG¡¦s training programme consisted of latissimus-dorsi pulls, seated chest press, seated rows, seated shoulder press, shoulder shrugs, bent knee crunches and diagonal crunches. Each exercise was performed for three sets of 15 repetitions each. These exercises were performed at 50% 1-repetition maximum (1-RM) for the first week, at 60% 1-RM for the second and third week and at 70% 1-RM for the fourth week. Once each subject¡¦s 1-RM was reevaluated after four weeks, the same intensity progression was followed for the fifth (50% 1-RM), sixth (60% 1-RM), seventh (60% 1-RM) and eighth (70% 1-RM) weeks. The CG was instructed to not take part in any structured exercise throughout the eight-week period. The present investigation made use of the dependent and independent paired t-tests. The CG¡¦s FEV1/VC ratio increased significantly (p „T 0.05) by 2.97% and VC decreased significantly by 4.46%, while the EG¡¦s PEF and PIF increased significantly by 12.6% and 13.9%, respectively. No statistically significant changes were found in FVC, FEV1, FEV1/FVC ratio, FEF-25, FEF-50 and FEF-75, IVC, ERV and VE for both the EG and CG. Both groups indicated no statistically significant changes in daily cigarette consumption from the pre- to post-tests. The investigation concluded that eight weeks of UBRT was insufficient to result in significantly positive changes in the majority of pulmonary function variables, except for PIF, in sedentary male smokers. / Dr. L. Lategan
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Spirometric reference standards in young Chinese children.January 2011 (has links)
Liu, Tak Chi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 112-125). / Abstracts and appendixes in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.viii / List of tables --- p.ix / List of figures --- p.xiii / List of Abbreviations --- p.xvi / List of Unit Abbreviations --- p.xvii / Table of Contents --- p.xviii / Chapter Chapter 1: --- Background and introduction --- p.P.1 / Chapter Chapter 2: --- Subjects and methods --- p.P.7 / Chapter 2.1 --- Study design and sampling frame --- p.P.7 / Chapter 2.2 --- Sample size calculation --- p.P.8 / Chapter 2.3 --- Study population --- p.P.11 / Chapter 2.4 --- Subject assessment in participating kindergartens --- p.P.13 / Chapter 2.5 --- Quality control for spirometric measurements --- p.P.18 / Chapter 2.6 --- Statistical analysis --- p.P.20 / Chapter 2.7 --- Outcome measures --- p.P.23 / Chapter 2.8 --- Participation and role in this study --- p.P.24 / Chapter Chapter 3: --- Results --- p.P.26 / Chapter 3.1 --- Comparison between the study populations in the training and research phases --- p.P.26 / Chapter 3.1.1 --- "Response rate, participation rate and success rate" --- p.P.27 / Chapter 3.1.2 --- Other factors --- p.P.31 / Chapter 3.2 --- Comparison between participants and non-participants in the research phase --- p.P.33 / Chapter 3.3 --- Comparison of factors between the subjects who succeed and failed to provide acceptable spirometric maneuvers which meet ATS/ERS standards in the research phase --- p.P.36 / Chapter 3.4 --- Comparison of lung function parameters between subjects who met and failed to meet the health criteria in the research phase --- p.P.39 / Chapter 3.4.1 --- Gestational birth age (< 37 weeks vs > 37 weeks) --- p.P.40 / Chapter 3.4.2 --- Birth weight (< 2.5kg vs > 2.5kg) --- p.P.41 / Chapter 3.4.3 --- Children with vs without current wheeze --- p.P.43 / Chapter 3.4.4 --- Children with vs without history of asthma ever --- p.P.44 / Chapter 3.4.5 --- Children with vs without recent respiratory tract infections (RTIs) --- p.P.45 / Chapter 3.5 --- The test-retest reliability --- p.P.47 / Chapter 3.6 --- "Relationship between lung function parameters and demographic, early-life, anthropometric and environmental factors in subjects who satisfied both health and ATS/ERS criteria in our research phase" --- p.P.50 / Chapter 3.6.1 --- Demographic factors --- p.P.51 / Chapter 3.6.2 --- Early-life factors --- p.P.53 / Chapter 3.6.3 --- Anthropometric factors --- p.P.56 / Chapter 3.6.4 --- Environmental factors --- p.P.57 / Chapter 3.7 --- Reference standards for incentive spirometry: Reference equations and normograms --- p.P.59 / Chapter Chapter 4: --- Discussions --- p.P.76 / Chapter 4.1 --- Pioneering incentive spirometry in Hong Kong preschoolers: Training and research phases --- p.P.77 / Chapter 4.2 --- Participants and non-participants in the research phase --- p.P.79 / Chapter 4.3 --- Subjects who succeed and failed to give acceptable maneuvers which meet ATS/ERS standards in the research phase --- p.P.81 / Chapter 4.4 --- "The relationship between demographic, anthropometric and environmental factors and spirometric parameters in local young children" --- p.P.84 / Chapter 4.41 --- Environmental tobacco smoke exposure and maternal smoking --- p.P.85 / Chapter 4.42 --- Place of birth --- p.P.87 / Chapter 4.43 --- Obesity and underweight --- p.P.89 / Chapter 4.44 --- Breastfeeding practice --- p.P.91 / Chapter 4.45 --- "Birth factors: mode of delivery, birth weight and gestation birth age" --- p.P.92 / Chapter 4.46 --- "Indoor environment: pets, moulds and others" --- p.P.94 / Chapter 4.5 --- Evaluation of the test-retest reliability --- p.P.95 / Chapter 4.6 --- The relationship between the health criteria and spirometric parameters in local young children --- p.P.96 / Chapter 4.7 --- The spirometric reference standards in Chinese preschool children in Hong Kong: Comparisons with published findings in different ethnic groups --- p.P.98 / Chapter 4.8 --- Drawbacks and limitations of this study --- p.P.105 / Chapter 4.9 --- Future research directions --- p.P.110 / Chapter Chapter 5: --- Conclusions --- p.P.111 / References --- p.P.112 / Appendices --- p.P.126 / Chapter Appendix I: --- Invitation letter --- p.P.127 / Chapter Appendix II: --- Reply form --- p.P.129 / Chapter Appendix III: --- Consent --- p.P.130 / Chapter Appendix IV: --- ISAAC questionnaire --- p.P.134 / Chapter Appendix V: --- Subject report --- p.P.163
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Measurement of breath-by-breath oxygen consumption and carbon dioxide production in exercising calvesCreel, Earl E January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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The relationship of lung compliance to blood gas exchange and sigh during natural and artificial ventilationChuang, Tzu-Neng 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
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Cardiopulmonary exercise testing for high-risk South African surgical patients.Biccard, Bruce M. January 2007 (has links)
Aim: To determine the prognostic value of cardiopulmonary exercise testing (CPET) for major vascular surgery in South African patients. Methods: CPET has been used in Durban since October 2004 to predict cardiac risk for high-risk patients undergoing major vascular surgery. A submaximal 'anaerobic threshold' (AT) test was conducted on all high-risk patients. Patients were classified into two groups: 'low AT' where the oxygen consumption at the AT was <1 lml.kg^.min"1 for cycling or < 9ml.kg"1.mkf1 for arm cranking and 'high AT' when the patient surpassed these targets. Analysis of all in-hospital deaths following surgery was conducted by two independent assessors blinded to the CPET test result. Deaths classified as primarily 'cardiac in origin' have been used in this retrospective cohort analysis. Results: The AT measured during CPET was not a statistically significant pre-operative prognostic marker of cardiac mortality. However, the survivors of the patients with a 'low AT' may be identified by their response to increasing metabolic demand between 5 and 7 ml.kg^.min"1. Survivors were more dependent on increasing heart rate, while non-survivors were more dependent on oxygen extraction. When this information is added to the AT, CPET was the only test statistically associated with cardiac mortality, in comparison to Lee's Revised Cardiac Risk Index and the resting left ventricular ejection fraction which were not statistically associated with cardiac death. A hundred percent of patients with a positive test died of cardiac causes, while 11% of the patients with a negative test had cardiac deaths. The risk ratio associated with cardiac death following a positive test was 8.00 [95% CI 3.8-16.9]. The sensitivity was 0.25 [95% CI 0.04-0.64], the specificity was 1.00 [95% CI 0.90-1.00], the positive predictive value was 1.00 [95% CI 0.20-0.95] and the negative predictive value was 0.88 [95% CI 0.74-0.95]. Conclusions: CPET provides valuable prognostic information in our surgical population. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2007.
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