Delay and disruption (DD) to contractors’ progress, often resulting in time and cost overruns, are a major source of claims and disputes in the construction industry. At the heart of the matter in dispute is often the question of the extent of each contracting party’s responsibility for the delayed project completion and extra cost incurred. Various methodologies have been developed over the years as aids to answering this question. Whilst much has been written about DD, there is limited information on the extent of use of these methodologies in practice. The research reported in this thesis was initiated to investigate these issues in the UK, towards developing a framework for improving DD analysis. The methodology adopted in undertaking this research was the mixed method approach involving first, a detailed review of the relevant literature, followed by an industry-wide survey on the use of these methodologies and associated problems. Following this, interviews were conducted to investigate the identified problems in more depth. The data collected were analysed, with the aid of SPSS and Excel, using a variety of statistical methods including descriptive statistics analysis, relative index analysis, Kendall’s concordance and factor analysis. The key finding was that DD analysis methodologies reported in the literature as having major weaknesses are the most widely used in practice mainly due to deficiencies in programming and record keeping practice. To facilitate the use of more reliable methodologies, which ensure more successful claims resolution with fewer chances of disputes, a framework has been developed comprising of: (i) best practice recommendations for promoting better record-keeping and programming practice and; (ii) a model for assisting analysts in their selection of appropriate delay analysis methodology for any claims situation. This model was validated by means of experts’ review via a survey and the findings obtained suggest that the model is valuable and suitable for use in practice. Finally, areas for further research were identified.

L’endométriose est devenue un problème de santé important du fait de sa prévalence (près d'une femme sur dix), des multiples complications engendrant un coût notable pour la société. Le coût de la maladie est aussi le coût de ses conséquences : traitements de l'infertilité mais aussi perte de productivité des femmes et de leur entourage, et ne sont encore pas clairement identifiés. Ces conséquences sont d'autant plus importantes qu'il existe un retard diagnostique (délai diagnostique moyen supérieur à 6 ans), or plus celui-ci est long, plus la maladie est découverte à un stade sévère et les patientes à un stade sévère ont davantage de complications, nécessitent une prise en charge plus lourde et plus coûteuse, ce à quoi il faut ajouter l’errance médicale et les traitements inadéquats. La volonté d'une meilleure connaissance et reconnaissance de la maladie a abouti à des actions du monde associatif, relayées. L’évaluation économique des prises en charge, à partir d’études de cas, est un outil important d’optimisation les choix pour améliorer le sort des patientes. Cette thèse se décompose en cinq chapitres : dans le premier chapitre nous nous intéressons aux aspects théoriques de l’évaluation économique en santé et méthodologiques de l’évaluation de coût social de la maladie. Le second chapitre traite de la maladie de l’endométriose en détails et de la méthodologie adoptée dans les études de cas qui sont présentés dans les chapitres trois, quatre et cinq. Le troisième chapitre présente une étude multicentrique sur les coûts et la qualité de vie des femmes souffrant des symptômes associés à l’endométriose en Europe. Le quatrième chapitre étudie prospectivement le coût sociétal de l’endométriose en France. Enfin, le cinquième chapitre est consacré à une étude rétrospective sur la persistance des coûts associés à l’endométriose dans le temps.Cette thèse montre l’importance de l’endométriose sur le système de soins en termes de coût (€ 10,6 milliards par an en France) et illustre la nécessité d'améliorer la prise en charge en direction d’interventions plus précoces et de recours plus rapides à des centres de compétence. A une efficacité constante, il est possible d’estimer la réduction de coûts liés à une politique plus productive. Améliorer la qualité des diagnostics et des prises en charge permette aussi de maximiser l’utilité affectée aux femmes en termes de qualité de vie. / Endometriosis becomes an increasingly major health problem because of its prevalence (nearly one woman out of ten), multiple complications leading to a significant cost on the society. The cost of the disease is also the cost of its consequences which are the treatments of infertility and also the loss of productivity of women and their entourage that are not yet clearly identified. These consequences are more important when there is a delay in the diagnosis (the average delay of diagnosis is longer than 6 years), but the longer the period of diagnosis is, the more the disease will be detected in a more severe stage. The patients at this severe stage have more complications, requiring more expensive care, to which must be added the medical wandering and the inadequate treatment.The desire for a better knowledge and recognition of the disease has resulted in associative actions all around the world. The economic evaluation of health care, based on case studies, is an important tool to optimize the choices to improve the situation of the patients. This thesis is divided into five chapters : the first chapter attempts to elucidate framework of health economic evaluation and the evaluation of the social cost of illness. The second chapter focuses on the endometriosis disease in detail and the methodology used in the case studies presented in Chapter Three, Four and Five. The third chapter presents a multicenter study on the costs and quality of life of women suffering from symptoms associated with endometriosis in Europe. The fourth chapter is concerned with a prospective study on the societal cost of endometriosis in France. The fifth chapter is devoted to a retrospective study on the persistence of costs associated with endometriosis over time.This thesis shows the importance of endometriosis on the health care system in terms of cost (€ 10.6 billion per year) and illustrates the need to improve care in favor of earlier interventions and an earlier refer to competence centers. With constant efficiency, it is possible to estimate the cost reduction linked to a more productive policy. Improving the quality of diagnosis and management also maximizes the affected usefulness of women in terms of quality of life.