The overwhelming trend of the usage of multimedia services has raised the consumers' awareness about quality. Both service providers and consumers are interested in the delivered level of perceptual quality. The perceptual quality of an original video signal can get degraded due to compression and due to its transmission over a lossy network. Video quality assessment (VQA) has to be performed in order to gauge the level of video quality. Generally, it can be performed by following subjective methods, where a panel of humans judges the quality of video, or by using objective methods, where a computational model yields an estimate of the quality. Objective methods and specifically No-Reference (NR) or Reduced-Reference (RR) methods are preferable because they are practical for implementation in real-time scenarios. This doctoral thesis begins with a review of existing approaches proposed in the area of NR image and video quality assessment. In the review, recently proposed methods of visual quality assessment are classified into three categories. This is followed by the chapters related to the description of studies on the development of NR and RR methods as well as on conducting subjective experiments of VQA. In the case of NR methods, the required features are extracted from the coded bitstream of a video, and in the case of RR methods additional pixel-based information is used. Specifically, NR methods are developed with the help of suitable techniques of regression using artificial neural networks and least-squares support vector machines. Subsequently, in a later study, linear regression techniques are used to elaborate the interpretability of NR and RR models with respect to the selection of perceptually significant features. The presented studies on subjective experiments are performed using laboratory based and crowdsourcing platforms. In the laboratory based experiments, the focus has been on using standardized methods in order to generate datasets that can be used to validate objective methods of VQA. The subjective experiments performed through crowdsourcing relate to the investigation of non-standard methods in order to determine perceptual preference of various adaptation scenarios in the context of adaptive streaming of high-definition videos. Lastly, the use of adaptive gain equalizer in the modulation frequency domain for speech enhancement has been examined. To this end, two methods of demodulating speech signals namely spectral center of gravity carrier estimation and convex optimization have been studied.

Mainly used for decorative purpose in the textile industry, lace is a type of lightweight, openwork fabric. The process of lace manufacturing is complex but much of it has been highly automated with the advancement of modern technology. One exception is the lace cutting operation which is used to cut the wide lace webs (as wide as 3.8 m) knitted from automatic knitting machines into individual lace breadths. Currently, lace cutting IS carried out by skilled operators or a low speed mechanical cutting system, leading to high cost and increased product lead times. Therefore the lace cutting operation has become a bottleneck of the whole process oflace manufacturing and its automation is highly desired. Based on the combination of machine vision and laser cutting technology, two automatic lace cutting systems have been developed in Loughborough University, which have fully demonstrated the feasibility of replacing the slow and expensive traditional lace cutting methods. However, the edge quality of the lace cut by these systems is not satisfactory enough to meet the requirements of demanding lace markets. In this thesis, based on the investigation of the effect of handling tension on lace cutting edge quality and the microstructure of lace, a strategic lace cutting solution has been presented. The cutting strategy is aimed at tensioning and exposing the loop thread by strategically tensioning and cutting individual threads. The loop thread is considered critical to cutting lace with a high quality finish. To automatically implement the cutting strategy, a machine vision system has been developed. An automatic lace transport and tensioning rig has been designed and manufactured. The long term aim of this rig is to be able to transport and tension lace continuously for lace cutting and apply localised tension on individual threads with the vision system providing feedback for tension control. The work in this thesis has been limited to manual adjustment of the rig to prove the initial ideas for this concept. An integrated vision guided, pulsed laser cutting system for lace cutting has been developed, based on which two types of representative lace have been cut. According to the assessment results of using a combination of user trials, microscopic and newly developed measurement techniques, the lace cut by this newly developed system has shown significant improvement in cutting edge quality, when compared to the lace cut by the previous laser cutting systems.

The overall purpose of this study was to examine how Certified Public Accountants (CPAs) perceive the potential use of assurance services to assess quality in accounting education programs. Survey questionnaires were mailed to a random sample of 250 CPAs in the north central Texas area. The questionnaire was designed to obtain demographic information and information relating to the respondents' perceptions of quality assessment of accounting education programs. An analysis of the results of this study suggest the following: CPAs consider (1) certain established criteria, such as SAT scores and faculty-to-student ratios, as effective measures for assessing quality attributes in accounting education programs and (2) traditional measures currently used for quality assessment in accounting education programs as only moderately effective by CPAs. CPAs are apparently seeking increased involvement with accounting education quality assessment and formulation of educational standards. They view the potential application of assurance services to accounting education quality as a way to offer a wider range of services to the public. CPAs perceive assurance services as a type of quality assessment that can be used to complement, but not replace, some of the more effective traditional methods, and as a way of enhancing the quality assessment process for accounting education.

<p>Cilj ove doktorske disertacije je bio da se oceni mogućnost upotrebe tri sorte domaće &scaron;ljive, različitih epoha sazrevanja (Čačanska rana, Čačanska lepotica i Požegača), kao sirovina za proizvodnju voćnog vina. Utvrđeni mehanički sastav plodova i hemijske karakteristike kljuka i soka ispitivanih sorti &scaron;ljive ukazuju da se čačanska lepotica i Požegača mogu smatrati boljim sirovinama za proizvodnju voćnog vina u odnosu na sortu Čačanska rana. Vr&scaron;ena je optimizacija uslova alkoholne fermentacije (temperature, vrednosti pH, trajanja fermentacije i doze enzimskog preparata), u sklopu koje je, takođe, ispitana i upotreba različitih pektolitičkih enzima za tretman kljuka i ocenjen uticaj upotrebe različitih sojeva kvasaca, kao proizvodnih mikroorganizama, na kvalitet vina od &scaron;ljive. Utvrđeno je da, među ispitanim proizvodnim organizmima, kvasac Spriferm (S. cerevisiae) daje vino od &scaron;ljive najboljeg kvaliteta. Postupkom numeričke optimizacije dobijene su sledeće vrednosti procesnih parametara fermentacije vina od &scaron;ljive: temperatura 25 &deg;C, vrednost pH 3,5 i doza pektolitičkog enzima 0,5 g/100 kg. Pri navedenim uslovima dobijeni fitovani modeli predviđaju prinos etanola od 7,5% v/v, prinos glicerola od 5g/l, prinos vina od 48% (48 ml vina na 100 g kljuka) i formiranje 710 mg/l metanola. Karakterizacija proizvedenog vina od &scaron;ljive podrazumevala je određivanje sadržaja najvažnijih sastojaka: alkohola, kiselina, mineralnih materija, fenolnih i aromatičnih jedinjenja, kao i ocenu njegovih funkcionalnih karakteristika (antiradikalske, antimikrobne i antiproliferativne aktivnosti). Na kraju, ocenjena je mogućnost smanjenja produkcije metanola u vinu od &scaron;ljive primenom različitih fizičko-hemijskih tretmana kljuka. Utvrđena je značajno veća efikasnost postupaka koji uključuju neki vid toplotnog tretmana kljuka u odnosu na postupke koji podrazumevaju upotrebu određenog enolo&scaron;kog sredstva.</p> / <p>The aim of this PhD thesis was to assess the possibility of using three native plum varieties, with different ripening periods (Ĉaĉanska rana, Ĉaĉanska lepotica and Poņegaĉa), as raw material for the production of fruit wines. Determined mechanical composition and chemical characteristics of fruit pomace and juice indicate that the Ĉaĉanska lepotica and Poņegaĉa are considered as better raw materials for the production of fruit wine compared to Ĉaĉanska rana. Optimization of fermentation conditions (temperature, pH, the duration of fermentation and the dose of pectolytic enzyme) was conducted. This step also included investigation of the different pectolytic enzymes use for the treatment of pomace and evaluated the impact of using different yeast strains, as well as the effect of different production microorganisms on the plum wine quality. It was found that, among the tested production microorganisms, Spriferm (S. cerevisiae) yeast gives the plum wine of best quality. Numerical optimization procedure resulted with the following values of the process parameters of plum wine fermentation: temperature 25 &deg;C, pH value 3.5 and pectolytic enzyme dose of 0.5 g/100 kg. Under these conditions the obtained fitted models predict the ethanol yield of 7.5% v/v, glycerol yield 5 g/l, the wine yield of 48% (48 ml from 100 g of pomace) and the formation of 710 mg/l of methanol. Characterization of the produced plum wines included the determination of the most important ingredients: alcohol, acids, minerals, phenolic and aromatic compounds, as well as evaluation of their functional characteristics (antiradical, antimicrobial and antiproliferative activities). Finally, the possibility of reducing the methanol production in plum wine was estimated by applying different physico-chemical treatments of the pomace. Significantly higher efficiency of procedures that involve some form of heat treatment of pomace, compared to treatments which involve the use of certain oenological means, was observed.</p>

As there is a rapid growth in the field of wireless communications, the demand for various multimedia services is also increasing. The data that is being transmitted suffers from distortions through source encoding and transmission over errorprone channels. Due to these errors, the quality of the content is degraded. There is a need for service providers to provide certain Quality of Experience (QoE) to the end user. Several methods are being developed by network providers for better QoE.The human tendency mainly focuses on distortions in the Region of Interest(ROI) which are perceived to be more annoying compared to the Background(BG). With this as a base, the main aim of this thesis is to get an accurate prediction quality metric to measure the quality of the image over ROI and the BG independently. Reduced Reference Image Quality Assessment (RRIQA), a reduced reference image quality assessment metric, is chosen for this purpose. In this method, only partial information about the reference image is available to assess the quality. The quality metric is measured independently over ROI and BG. Finally the metric estimated over ROI and BG are pooled together to get aROI aware metric to predict the Mean Opinion Score (MOS) of the image.In this thesis, an ROI aware quality metric is used to measure the quality of distorted images that are generated using a wireless channel. The MOS of distorted images are obtained. Finally, the obtained MOS are validated with the MOS obtained from a database [1].It is observed that the proposed image quality assessment method provides better results compared to the traditional approach. It also gives a better performance over a wide variety of distortions. The obtained results show that the impairments in ROI are perceived to be more annoying when compared to the BG.

A necessidade de se considerar o sedimento na análise da qualidade de corpos de água motivou a realização desse estudo, visando contribuir para o estabelecimento de protocolos de testes com o anfípoda Hyalellla, critérios para a avaliação da toxicidade de sedimentos de água doce e um quadro da situação atual das principais bacias do Estado de São Paulo, em termos ecotoxicológicos. Desta forma, inicialmente, foi comparada a sensibilidade de duas espécies de Hyalella, ou seja H. azteca e Hyalella sp., adotando diferentes substâncias e sedimentos. Também comparou-se a taxa de fecundidade e sobrevivência destas duas espécies em determinadas condições de cultivo. Após a escolha da espécie teste mais adequada, Hyalella azteca, foram avaliadas diferentes condições de cultivo (tipo e quantidade de alimento) e de ensaio (sistema estático e semi-estático, razão de sedimento e água 1:4 e 1:2, os critério de avaliação sobrevivência e crescimento) com amostras de sedimento, apresentando diferentes graus de contaminação. Esse estudo permitiu estabelecer uma condição de cultivo (100 organismos em recipientes com 2,5L de água natural ou reconstituída, a planta aquática Elódea como substrato e, como alimento, ração de coelho granulada mais uma solução de ração de peixe digerida, levedura e óleo de prímula). Esta condição permitiu obter um número médio de jovens/fêmea/semana de H. azteca de 9,2 com um desvio padrão de 2,7. Para avaliar a condição de ensaio que melhor representaria as do ambiente, os resultados dos testes de toxicidade com Hyalella azteca foram comparados com dados químicos e da comunidade bentônica, de amostras coletadas no mesmo local e data. Dessa forma verificou-se que a melhor condição de teste de toxicidade, com a duração de 10 dias, com H. azteca foi em sistema semi-estático com trocas de água a cada dois dias, adotando a razão de sedimento e água de 1:2 e avaliando a mortalidade e o crescimento. A partir desses dados, foram elaborados critérios que expressam classes de qualidade de sedimentos, ou seja: bom, quando o sedimento não apresentou toxicidade; regular, efeito sub-letal (redução do crescimento); ruim, mortalidade <50% e péssimo, mortalidade >=50%. Esse critério foi aplicado nos estudos realizados para avaliação da qualidade dos sedimentos em 12 das 22 das Unidades de Gerenciamento de Recursos Hídricos, para os quais foram compilados e selecionados dados ecotoxicológicos, além de químicos e da comunidade bentônica, quando disponíveis. A análise integrada desses resultados, utilizando classes de qualidade para as variáveis químicas, ecotoxicológicas e índices para a comunidade bentônica, permitiu estabelecer uma melhor avaliação da qualidade dos sedimentos. Além disso, verificou-se a importância de se integrar outros dados, como deformidade em Chironomus e teste de mutagenicidade, para se confirmar ou não a presença e estabelecer possíveis grupos de compostos, que poderiam estar causando impactos na comunidade de organismos que vivem no sedimento. A integração dessas diferentes linhas de evidências é que permitiu o estabelecimento do diagnóstico ou das análises a serem realizadas para se determinar o tipo de agentes estressores que possam estar presentes em um dado local em estudo. Portanto, testes de toxicidade se mostraram úteis e necessários na caracterização e em estudos para avaliar e identificar a qualidade de sedimentos, e devem ser adotados no monitoramento, junto com outras variáveis. / The need to include the sediment evaluation in the quality assessment of surface waters, motivated this study, in order to contribute to the establishment of testing protocols with the amphipod Hyalella, to toxicity evaluation criteria. It was also motivated by a lack of a survey of the São Paulo State freshwater quality sediment watersheds situation in terms of toxicity. Initially, the sensitivity of two Hyallela species, H. azteca and Hyalella sp. (previously named H. meinerti), were compared using different substances and sediment samples. The rates of fecundity and survival of these two species were compared in standardized culture conditions. After the selection of the most suitable species, Hyalella azteca, different culturing conditions (food type and quantity) and assays design (semi-static and static system, water/sediment ratio 1:2 and 1:4, evaluation criteria for survival and growth) were studied using sediment with different contamination levels. The best culturing conditions were: 100 organisms/2.5 liters of natural or reconstituted water; the aquatic plant Elodea as substrate and rabbit granulated food plus a mixture of digested fish food, yeast and primula oil. Adopting this culturing conditions it was possible to obtain 9.2 juvenile Hyalella azteca for each female/week with a standard error of 2.7 for around three months. In order to evaluate the best test conditions, the toxicity tests results were compared with chemical analysis and benthic community data. These results were obtained with samples collected in the same sites and at the same time. The analyses of the results showed that the best condition for 10 days exposition time was semi-static system with water exchange every two days, 1:2 sediment/water ratio and evaluation of mortality and growth as endpoints. Based in these results, a toxicity criteria that express sediment quality classes were elaborate. The classes established were: good, when the sediment was non toxic, regular when sublethal effect were observed (growth reduction), bad, when the mortality was less than 50% and extremely bad, when mortality was equal or greater than 50%. These criteria were applied to analyze toxicity data from different sediment quality studies performed in 12 from the 22 Freshwater Watershed Management Units of São Paulo State that were compiled and selected, using ecototoxicological, chemical and benthic community data when available. Only using sediment classes for these three variables it was possible to establish the sediment quality of the survey data. Other variables (benthic deformities and mutagenicity) were considered important to confirm, or not, the presence and establish the possible chemical groups that could be causing effects on benthic organisms. Only by the integration of these different evidence lines it was possible to define the sediment quality or which analyses should to be done in order to point out the stressor types that could be present at the studied sites. The conclusion was that toxicity tests with aquatic organisms are reliable and necessary for the quality evaluation and identification of toxicity of the sediments and should be used in monitoring studies together with other tools.

Background: Patient evaluation of primary health care (PHC) as a recognised means of obtaining important information for quality improvement can be enhanced with the availability and use of acceptable, reliable and valid questionnaires. This research reports the development and validation of the patients' evaluation scale (PES) for assessment of the quality of primary health care in Nigeria. Methods: Mixed methods design was used to develop and validate items, response scale and domains in the Patients' Evaluation Scale. Items were derived from literature review and content analysis of interviews with patients. Face and content validity were established with primary health care experts and patients while quantitative pilots were conducted to determine questionnaire's acceptability across groups and appropriate response format. The conduct of a large multi-centre psychometric validation survey was used to determine the internal structure (exploratory factor analysis), reliability (internal consistency), construct, criterion and discriminative validities (Pearson's correlation coefficient, structural equation modelling using regression equation method) and acceptability (scale and item response pattern) of the questionnaire. The discriminatory properties were assessed by questionnaire's ability to differentiate population groups' scores in line with 'a priori' hypotheses. Results: The development resulted in the long and shortened forms of PES containing 27 and 18-items respectively. Both showed good indices for validity and acceptability among various population groups in Nigeria. PES-SF resulted from the deletion of items in PES that didn't meet recommended Eigen value < 1, factor loading < 0.5, item-total, item-domain correlation < 0.4 and item-item correlation within domains of < 0.2. PES-SF has Cronbach's alpha of 0.87 for entire questionnaire and 0.78, 0.79 and 0.81 respectively for the three domains (codenamed 'facility', 'organisation', and 'health care'). The three components solution from the Scree plot explained 56.6% of the total variance of perceived quality. Items correlated significantly higher with domain identified through factor analysis than with other domains. In line with 'a priori' hypothesis, scale and domains scores of PES-SF could differentiate population groups based on patients' clinical and socio-demographic characteristics. PES-SF scores also showed significant correlation with patient general satisfaction and likelihood of returning or recommending others to the PHC centres. Conclusion: The patient evaluation scale designed for exit assessment of patients' experiences with PHC in Nigeria shows good measurement properties. It will be useful to clinicians, researchers and policy makers for patient-focused quality improvement activities in Nigeria. Further research will involve translation to major Nigerian languages and to assess PES validity against observed quality criteria.

La maîtrise de la qualité est aujourd’hui indispensable pour satisfaire les exigences des clients. Bien qu’il existe différentes méthodes et outils spécialement développés pour manager la qualité des systèmes ou des processus au sein des entreprises, il est difficile d’établir le lien entre la maîtrise des nombreux processus d’une entreprise et la qualité produit pour un système en service. Dans ce contexte, une thèse CIFRE a été menée au sein de MBDA, entreprise qui conçoit, développe et produit des systèmes d’armes. La problématique de cette thèse est de développer une méthodologie permettant de produire une définition de la qualité produit d’un système complexe qui soit valable tout au long de son cycle de vie, et permettant la construction de modèles de prévision de la qualité produit en utilisation lors du développement et de la production. Notre contribution consiste en une méthodologie en deux phases. La première phase permet d’établir une définition de la qualité produit des systèmes complexes du point de vue du client adaptée au contexte industriel en définissant plusieurs facteurs qualité produit qui soit valable pour toutes les phases du cycle de vie des systèmes. La deuxième phase permet de construire des modèles de prévision de la qualité produit qui permettent d’obtenir une évaluation de la qualité tout au long du cycle de vie des systèmes et d’établir une prévision de ce que sera la qualité en utilisation. Les deux phases de la méthodologie reposent sur l’exploitation d’avis d’experts afin de permettre son utilisation sans disposer d’une quantité importante de données. Les modèles construits ont été testés pour des systèmes développés par MBDA. / Today, quality control is essential to satisfy customer requirements. Although there are different methods and tools specially developed to manage the quality of systems or processes within companies, it is difficult to establish the link between management of a company's many processes and product quality for a system in service. In this context, a CIFRE thesis was conducted within MBDA, a company that designs, develops and produces weapons systems. The problem of this thesis is to develop a methodology allowing to produce a definition of the product quality of a complex system which is valid throughout its life cycle, and allowing the construction of models to predict the product quality in use during development and production. Our contribution consists of a two-phase methodology. The first phase makes it possible to establish a definition of the product quality of complex systems from the customer's point of view adapted to the industrial context by defining several product quality factors that are relevant for all phases of the systems life cycle. The second phase builds product quality prediction models that provide a life-cycle quality assessment of the systems and a forecast of what the quality will be in use. Both phases of the methodology rely on the use of experts' judgement to enable its use without a significant amount of data. The models built have been tested for systems developed by MBDA.

Comme la consommation de médias numériques a explosé ces dernières années, faire des photos esthétiques, avec ou sans expertise artistique, est plus que jamais un sujet de recherche. Plusieurs axes peuvent être explorés: la haute définition, la luminance ou contraste étendue, les gamut couleur étendus. En plus de ces propriétés intrinsèques de l'image, des connaissances perceptuelles et/ou artistiques seraient de grande valeur pour tout utilisateur manipulant le contenu des images. Cette thèse propose d'aborder le thème de l'harmonie des couleurs. La littérature en lien avec ce sujet se retrouve à travers diverses disciplines : la science des couleurs, le traitement d'image, la psychologie… Ces expériences menées en science des couleurs privilégient la mesure de patchs combinant deux ou trois couleurs, rendant l'extrapolation à des images naturelles impossibles. D'autres approches ont défini des lois empiriques dictant l'arrangement des couleurs sur la roue des teintes. Le cadre applicatif de ces modèles géométriques manque de rigueur quant à leur utilisation. Malgré cela, des algorithmes en traitement d'image employant ces modèles ont vus le jour. Si les résultats semblent qualitativement agréables, ces algorithmes méritent une validation plus quantitative et objective, faisant intervenir une base de données appropriée. Dans cette thèse, deux approches sont mises en perspective: un travail expérimental et une partie algorithmique. Une expérience a été menée à l'aide d'un oculomètre avec une tâche dédiée à l'analyse de l'harmonie des couleurs, permettant de mesurer des effets dans le déploiement de l'attention visuelle. A partir de ces données, une vérité terrain a été extrapolée, permettant la validation des méthodes algorithmiques ensuite proposées. En premier, nous avons amélioré l'état de l'art sur l'harmonisation automatique des images au travers de diverses contributions et avons démontré de façon exhaustive le gain de notre approche. En deuxième contribution algorithmique, nous avons introduit une nouvelle sorte de métrique de qualité qui combine les concepts de masquage visuel et d'harmonie des couleurs. Ainsi, nous pouvons prédire quelles zones de l'image seront perçues harmonieuses, au vue de leur voisinage et donc des effets de masquages potentiels. Enfin, une dernière contribution, nous a amené à dériver deux outils d'édition incorporant les deux techniques précédentes, permettant de rendre accessible les concepts d'harmonie des couleurs à travers une formulation cachée et intuitive. / Since the consumption of digital media exploded in the last decade, making aesthetic pictures quickly - with or without artistic expertise - is more than ever a research topic. Different axis of investigations remain possible: high resolution, high dynamic range or wide color gamut. Additionally to these objective image properties, more perceptual and artistic insights could be of benefit to any user manipulating pictures. In such context, this thesis deals with the topic of Color Harmony. The literature related to this topic is limited, but involves many different scientific areas: color science, image processing and psychology and so on. The validity of collected data is questionable due to their limitation to two- or three-colors patches. The models fitted from these data remain non-exploitable on natural pictures. Other models depicting rules or areas on color wheel lack scientific guidelines for their utilization. Nonetheless, some algorithms employing color harmony theory and models as a core concept showed up in the literature, but suffered from being quantitatively tested and validated. In this thesis, two views are put in perspective in order to respond to the previous statements: an experimental and a computational approaches. The conducted experiment allowed observing some effects with an eye-tracking protocol, never applied before with a task on color harmony assessment. From the collected data of our experimental work, we designed a method to generate a ground truth, which would serve to the validation of the two proposed computational methods. First, we improved an existing architecture for automatic color harmonization and demonstrated exhaustively the benefit of our approach. As a second computational contribution, a novel quality metric is introduced that integrates the concepts of visual masking and color harmony. Thus, we may predict which areas would be perceived harmonious regarding its neighborhood and then the potential masking effects. As a last contribution, two editing tools made accessible the color harmony theory through a hidden formulation of it and a user-friendly and intuitive interface.

One way internet users determine the quality of a website is to look for so called 'credibility factors'. These factors can either be positive: the presence of a date, reference list, independent site certification; or negative: the presence of advertisements or broken links. This thesis investigates what role such factors play in the effectiveness of two e-health interventions. An e-health intervention is a health related website designed to change a person’s behaviour. Until now research into credibility has been largely theoretical. Studies have relied on subjective outcome measures such as Likert scales, website content recall, expressions of preference and self reported behaviour. This thesis describes two studies, the second of which investigates, for the first time, whether surface credibility manipulations change objective behavioural outcomes. Surface credibility is how much a perceiver believes a website on simple inspection. Based on a comprehensive literature review of credibility research, the following credibility factors were explored: presence of advertising, recognisable logos, contact details, physical address, references, third party certification, currency information, privacy statement, HTTPS encryption, top level domain and presence of a broken link. The first study involved the assembly of an exercise promotion website. Participants were randomised to receive the site modified to contain either factors heightening credibility or those lowering credibility. Participants using the high credibility version spent twice as long browsing the site as those using the low credibility version. There was no effect on attitude to exercise or self reported physical activity. The second study used the same methodology but with a website targeting an objectively measurable health behaviour (registration as an organ donor). In this study 889 university students were exposed to a website promoting organ donation. Information on the site was assembled based on theoretical domain interviewing and current research into organ donation interventions. 336 (37.79%) participants registered through the study website. The study detected no significant difference in registration rates between high and low credibility versions of the site. Of the 17 comments left on the low credibility site, only 3 were credibility related criticisms. It is the finding of this thesis that university students are willing to submit personal information and place trust in a website contravening many current credibility guidelines. Future studies into credibility are needed to explore why this is the case. One possibility is that the website was trusted simply because it was part of a research study. Another possibility is that the high quality of the textual content compensated for the lack of credibility of the site itself. It is the recommendation of this thesis that future studies focus on objective behavioural outcome measures and control for other forms of credibility such as participation in a research study.