• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 12
  • 3
  • 2
  • 2
  • 1
  • Tagged with
  • 29
  • 29
  • 29
  • 12
  • 8
  • 7
  • 6
  • 6
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 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

A Markov Random Field approach to the analysis of texture in digitised mammograms

Merouani, Hayet Farida January 1999 (has links)
No description available.
2

Models to evaluate schemes for an early detection of breast cancer

Ouinten, Y. January 1988 (has links)
No description available.
3

The National Health Service Breast Screening Programme in Sheffield : service delivery and uptake

Thompson, Dawn Louise January 1998 (has links)
No description available.
4

Evaluation of rapid assays for the detection of radiosensitive breast cancer patients

Barber, James B. P. January 1998 (has links)
No description available.
5

An automated image analysis system for the detection of microcalcifications

Hojjatoleslami, S. A. January 1997 (has links)
The interpretation of medical images is one of the most difficult tasks in computer vision, largely because of the high degree of variability associated with normal and abnormal appearances. This thesis introduces a systematic method for the detection of microcalcifications as one of the most important signs of early breast cancer. It involves a four step procedure. The first step is blob detection to detect regions of microcalcification size range. The second step involves a specially designed directional region growing method to find the best fitting boundaries for each blob region. A newly developed combination of classifiers is then applied to label each region as a microcalcification or background. The final processing step involves a search for the existence of clusters of microcalcifications using a hierarchical nearest mean clustering method. The contributions of the work to the field of image processing are; a new blob detection system; a novel region growing method and a theoretical framework for combining classifiers which use a combination of shared and distinct representations. Here specifically, we present a blob detection method with the capability of detecting any suspected blob of specific size range. Then a new region growing method is developed based on a unique directional growing process providing predictable behaviour for the method. The application of two discontinuity measures is considered for the extraction of two fitting boundaries representing information about the region and its local background. The information conveyed by the boundaries and their associated regions is used to compute reliable representations for labelling each blob region. The robustness of the region growing method to the choice of a starting point and to Gaussian noise is examined on real images. We demonstrate that commonly used classifiers provide reliable results in labelling the suspected regions. In spite of achieving an acceptable performance using different individual classifiers, a decision fusion rule involving a weighted combination of classifiers is developed and its performance on the problem is investigated. The combination rule is applicable when mixed mode representations (some shared and some individual features) are used. A comparative study of the individtial classifiers and also of conventional classifier combination techniques with the weighted combiner is performed on independent test sets. The results achieved with the presented algorithm are very promising and approaching a level where a clinical pilot evaluation for screening purposes would be warranted.
6

Perceptions, Beliefs, and Behaviors Toward Breast Cancer Screening of Filipino Women in Saudi Arabia

Fronda, Cherry Rose Aguilar 01 January 2017 (has links)
Despite the existence of breast cancer screening that could promote early diagnosis and survival of breast cancer, high mortality rates of breast cancer persist among Filipino women. The purpose of the qualitative study was to describe the perceptions, beliefs, and behaviors of Filipino women working as Overseas Filipino Workers (OFWs) in Saudi Arabia. Face-to-face interviews were conducted with 20 Filipino women between the ages of 40 to 60 years who were recruited voluntarily using purposeful sampling technique. Guided by the structures of health belief model (HBM), the study used an inductive coding technique to elicit common themes from the raw data. The study established that the participants' screening behaviors were influenced by family history of breast cancer, the financial and emotional burden of the disease and its treatment, the benefit of early detection, mobility to participate, culture and language barriers, and the social media. The study also demonstrated that the desire to participate in breast cancer screening is influenced by the participants' perception of susceptibility and perception of severity to breast cancer. The findings of the study could create a positive social change as it may inform the practice of public health providers, influence the drafting of informed policies for comprehensive breast health care, and improve access to preventive health services for Filipino women OFWs. Furthermore, the study could empower Filipino women in their personal health decision making, especially when working in other countries where good health is the working capital and a precondition for survival.
7

Factors condicionants de la participació en un programa poblacional de detecció precoç del càncer de mama

Segura Noguera, Josep Maria 12 December 2001 (has links)
L'inici del programa de detecció precoç del càncer de mama en els districtes de Ciutat Vella i Sant Martí de la ciutat de Barcelona, va motivar la realització del primer estudi en el barri de la Barceloneta, amb l'objectiu d'analitzar diferents factors associats a la participació. La resposta després de la primera citació ha estat del 65%. S'ha relacionat amb l'historial clínic previ augmentant en quasi 4 vegades l'ods de resposta, i amb el receptor de la carta de citació, variant del 75% quan és la mateixa interessada fins el 47% quan la carta és dipositada a la bústia, i el 32% quan l'adreça és insegura. La resposta després de les citacions successives ha estat del 26%. S'ha relacionat amb l'historial clínic previ augmentant en quasi 8 vegades l'ods de resposta, i amb la raó de no haver vingut després de la primera citació, passant del 50% quan és circumstancial fins el 11% quan s'atribueix a manca d'interès. La taxa de cobertura (79%) disminueix amb l'edat, i augmenta amb el nivell educatiu.El segon estudi permet apreciar com prèviament al programa les mamografies no s'adequaven a les directrius europees. Un 59% de les dones entrevistades dels barris El Clot, Camp de l'Arpa i La Verneda, s'han fet una mamografia de cribratge en els últims quatre anys. Existeix una major utilització en dones més joves, de major nivell educatiu i que tenen historial clínic. La periodicitat era anyal en un 35%, biennal en un 38% i cada 2-4 anys en el 27% restant. El 58% de les mamografies s'han realitzat en la sanitat pública, que mostra el major percentatge (42%) de periodicitat biennal. En les dones participants, la visita al ginecòleg i la pràctica de citologia uterina han presentat la major associació (probabilitats 4 vegades superiors) amb la mamografia prèvia de cribratge. També s'han associat a una major utilització els antecedents personals de patologia mamària i familiars de càncer de mama, l'autoexploració mamària i la visita mèdica recent, mentre que l'autopercepció de salut ha presentat una relació inversa.Finalment, el tercer estudi és un assaig controlat aleatoritzat on s'han comparat tres diferents estratègies utilitzades per a invitar dones d'entre 50 a 64 anys a participar en el programa. L'estratègia del contacte directe incrementa de forma significativa fins un 22% la probabilitat de resposta després de la primera citació en les dones del barri de Raval Nord invitades. En el grup de contacte directe aquesta resposta era del 63%, comparat amb un 55% quan la carta era enviada pels professionals sanitaris del CAP, i un 52% quan era remesa pels responsables del programa. Aquest increment en el grup de contacte directe s'observa encara que sols s'ha aconseguit contactar en un 45% dels casos directament amb la mateixa dona. Quan aquest fet s'assoleix la resposta és del 72%. La utilització de professionals no sanitaris per a aconsellar les dones sembla ser una estratègia efectiva, particularment entre les dones de baix nivell educatiu. / The beginning of the breast cancer screening program in the Ciutat Vella and Sant Martí districts of Barcelona was the origin of the first study in the Barceloneta quarter, with the aim of analyzing different factors related to participation. The response after the first citation was 65%. Having a previous clinical history, increased in nearly 4 times the response odds. Response after the first citation was influenced by who the recipient of the citation letter was, ranging from 75% when this was the same person concerned to 47% when the letter was left in the letter-box, and to 32% when the address was uncertain. The response after subsequent citations was 26%. Having previous clinical history increased the response odds in almost 8 times. The response after successive citations, ranged from 50% when it was for circumstantial reasons, to 11 % when it was due to lack of interest. Coverage rate (79%) decreased with age, and increased with education level.The second study shows that, previously to the program, mammography screening did not comply with European guidelines. A screening mammography had been performed on 59 % of women interviewed in the El Clot, Camp de l'Arpa and La Verneda quarters. The utilization of mammography was higher among younger women, women with a higher education level, or who had previous visits to a physician. Periodicity was once a year in 35% of cases, once every two years in 38%, and every 2-4 years in the remaining 27 %. Mammographies were performed at the Public Heath Service in 58 % of cases. The Public Health Service shows the highest percentage (42 %) of biennial periodicity. The variables more strongly associated with the use of screening mammography (probabilities 4 times higher) were: visit to a gynecologist and performance of a pap smear. Also related to the utilization of screening mammography were: personal history of breast pathology, family history of breast cancer, breast self-examination, and recent visit to a general practitioner. Self-perceived health presented an inverse relation with screening mammography use.Finally, the third study is a randomized controlled trial where three different strategies of inviting 50 to 64 years old women to participate in the program were compared. The strategy of direct contact increased in a significant way, up to 22%, the possibility of response after the first citation among women invited in the Raval Nord quarter. The response rate in the direct contact group was 62%, compared to 55% when the letter was sent by Primary Health Care Team, and 52% when it was sent by those responsible of the program. This increase in the direct contact group is noticeable even though only in 45 % of cases it was possible to contact the subject herself. When this was achieved, response raised to 72%. Use of non-health professionals to advise women seems to be an effective strategy, especially among women with a lower educational level.
8

Depression, Psychological Distress and Breast and Cervical Cancer Screening: A Population-based Study in Ontario Women

Vigod, Simone Natalie 31 May 2011 (has links)
Purpose: The objective of this study was to investigate both depression and psychological distress as determinants of breast and cervical cancer screening. Methods: Ontario female respondents to the Canadian Community Health Survey version 1.2 (2002) were assessed for both Major Depressive Disorder (World Mental Health-Composite International Diagnostic Interview for depression) and psychological distress (Kessler 6-item Distress Scale (K6)>/= 8). Respondents eligible for screening (N=4042 for cervical cancer; N=1403 for breast cancer) were linked to Ontario administrative health service data to prospectively ascertain screening outcomes. Results: Women with K6 >/= 8 had reduced breast cancer screening compliance in adjusted analyses (AOR 0.63, 95% CI 0.40-0.97). The association between K6 >/= 8 and cervical cancer screening approached significance in women over age 40 (AOR=0.65, 95%CI 0.41-1.04). Conclusion: Decreased likelihood of screening in women with clinically significant psychological distress suggests that attention to adequacy of preventive services is a potential target for intervention.
9

Depression, Psychological Distress and Breast and Cervical Cancer Screening: A Population-based Study in Ontario Women

Vigod, Simone Natalie 31 May 2011 (has links)
Purpose: The objective of this study was to investigate both depression and psychological distress as determinants of breast and cervical cancer screening. Methods: Ontario female respondents to the Canadian Community Health Survey version 1.2 (2002) were assessed for both Major Depressive Disorder (World Mental Health-Composite International Diagnostic Interview for depression) and psychological distress (Kessler 6-item Distress Scale (K6)>/= 8). Respondents eligible for screening (N=4042 for cervical cancer; N=1403 for breast cancer) were linked to Ontario administrative health service data to prospectively ascertain screening outcomes. Results: Women with K6 >/= 8 had reduced breast cancer screening compliance in adjusted analyses (AOR 0.63, 95% CI 0.40-0.97). The association between K6 >/= 8 and cervical cancer screening approached significance in women over age 40 (AOR=0.65, 95%CI 0.41-1.04). Conclusion: Decreased likelihood of screening in women with clinically significant psychological distress suggests that attention to adequacy of preventive services is a potential target for intervention.
10

Modelling and prediction of parameters affecting attendance to the NHS breast cancer screening programme

Arochena, H. E. January 2003 (has links)
This thesis focuses on the modelling and prediction of factors affecting attendance to screening invitations of the NHS Breast Screening Programme. The analysis is based on data collected by the Warwickshire, Solihull and Coventry Breast Screening Unit from 1989 up to 2001 with respect to invitation to screening for the prevention of breast cancer in non-symptomatic women. Using a novel approach to the analysis of the data, from the perspective of the screening episode of each woman, rather than the usual analysis from the perspective of the screening round of the units, a statistical analysis is carried out on the whole registered population for the first time. Amendments to the current formulae for coverage calculations, the introduction of a new parameter (invitation rate) and the proposal for a reduction of the invitation period (period of time between two consecutive invitations) follows from the analysis. A preliminary analysis of predictive methodologies, including traditional statistical methods and artificial intelligent methods, gives the foundation to the formulation of two new algorithms; the first, for the prediction of attendance of women to screening invitations, and the second for the prediction of occurrence of screening variation (change of appointment dates) of women to invitations. Both algorithms are based on neural network generated models able to learn from the previous screening behaviour history of the woman, a technique not previously explored for the prediction of attendance. The accuracy of the new proposed algorithm for the prediction of attendance to invitation is tested on a blind study using data not previously seen by the predictive system, and for which results were unknown at the time when the predictions were made. From the obtained results, it is concluded to recommend the implementation by the NHS Breast Screening Unit of the two algorithms proposed for the prediction of the women’s attendance and screening variation to their invitation for screening. With these predictions, women likely not to attend, or change appointment date, can be identified and appropriately targeted with the aim of increasing their attendance in the short term, and in the long term, reducing breast cancer mortality.

Page generated in 0.1298 seconds