From 28 October 1999 to 26 September 2000 Mbeki publically endorsed the position of ‘denialist’ AIDS scientists – a marginal group who oppose the claim that HIV causes AIDS – and used their views as the basis for a policy of not providing ARVs (antiretrovirals – the treatment that prevents HIV from replicating) via the public health system. This policy persisted until 2004, with severe consequences – best estimates indicate that it resulted in 171,000 avoidable new infections and 343,000 deaths over the 1999 – 2002 period. I use this case to address two questions. First, is it reasonable for policy makers to consult non-mainstream scientists in the process of policy development? Second, can they be held personally morally responsible for the consequences of having done so when things go very badly wrong? I begin by providing a motivation for why philosophers should be interested in real-world cases. Having justified the philosophical “methodology” of this thesis, I move on to describing the specific case of South African AIDS denialism in the early 2000s. I then take a chronological step back in order to assess the rationality of accepting HIV as the sole cause of AIDS in 1984, when the virus was first identified. I argue that it was rational, but that some explanatory power was lost when other competing accounts of the disease’s aetiology were discarded. I argue that this explanatory loss can be accounted for by re-considering the way causation is understood in biomedicine and epidemiology. Having settled the scientific issues of the case, I then move on to the question of moral responsibility. I specifically look at when an agent can be held morally responsible for their ignorance, and the role of suppressed disagreement in the production of that ignorance.

Cardiovascular disease (CVD) is the biggest killer of people in western civilisation. Age is a significant risk factor for the development for CVD, and treatments and therapies to address this increased risk are crucial to quality of life and longevity. Exercise is one such intervention which has been shown to reduce CVD risk. Age is also associated with endothelial dysfunction, reduced angiogenic capabilities, and reduced ability to repair the vessel wall. Circulating angiogenic cells (CACs) are a subset of circulating cells which assist in the repair and growth of the vasculature and in the maintenance of endothelial function. Reductions in these cells are observed in those with vascular disease compared to age-matched healthy controls. Exercise may reduce CVD risk by improvements in number and/or function of these CACs. Data was collected from human volunteers of various ages, cardiorespiratory fitness (CRF) levels and latent viral infection history status to investigate the effects of chronological age, CRF, viral serology and other lifestyle factors, such as sedentary behaviours and exercise on CACs. The levels of CACs in these volunteers were measured using four colour flow cytometry using various monoclonal antibodies specific to cell surface markers that are used to identify specific subsets of these CACs. In addition, the response to acute exercise of a specific subset of these CACs, termed ‘angiogenic T-cells' (TANG) were investigated, in a group of well-trained males aged 20-40 years, using a strenuous submaximal exercise bout. Advancing age was associated with a decline in various subsets of CACs, including bone marrow-derived CD34+ progenitors, putative endothelial progenitor cells (EPCs) and also TANG cells. Individuals with a higher CRF were more likely to have higher circulating numbers of TANG cells, particularly in the CD4+ subset. CRF did not appear to modulate CD34+ progenitors or EPC subsets. Increasing sitting time was associated with reduction in TANG cells, but after correcting for the effects of fitness, sitting time no longer negatively affected the circulating number of these cells. Acute exercise was a powerful stimulus for increasing the number of TANG cells (140% increase), potentially through an SDF-1:CXCR4-dependent mechanism, but more studies are required to investigate this. Latent CMV infection was associated with higher number of TANG cells (CD8+), but only in 18-40 year old individuals, and not in an older age group (41-65 year old). The significance of this has yet to be understood. In conclusion, advancing age may contribute to increased CVD risk partly due to the observed reductions in angiogenic cells circulating in the peripheral compartment. Maintaining a high CRF may attenuate this CVD reduction by modulating TANG cell number, but potentially not CD34+ progenitor or EPC subsets. Acute exercise may offer a short window for vascular adaptation through the mobilisation of TANG cells into the circulation.

As of 2013, 39,000 Chileans have been diagnosed with HIV/AIDS; HIV (Human Immunodeficiency Virus) has a prevalence of 8.6 cases per hundred thousand people, and AIDS (Acquired Immune Deficiency Syndrome) has a prevalence of 5.4 cases per hundred thousand people. In addition, 99.2% of the cases have been reported as having been sexually transmitted. The objective of this study was to determine if a relationship existed between education level and HIV preventive actions. HIV preventive actions include the access to condoms, HIV-related diagnostic exams, and the dissemination of accurate preventative information. A descriptive analysis with data from the NIH-funded project, "Testing an HIV/AIDS Prevention Intervention for Chilean Women," was conducted. A total of four hundred women were included in this analysis (n=400). Pearson correlation was conducted to determine the strength of the relationships between the highest level of education completed and Papanicolau examinations, condom purchases or usage, sexual activity, communication with sexual partner and HIV/AIDS testing. We expect to see a strong positive correlation between education level vi and HIV-preventive actions-the lower the education level obtained, the less likely participants are to engage in HIV-preventive actions. The results of this study failed to demonstrate a correlation between education level and health-related preventive actions as demonstrated by the parameters evaluated here. The level of education of the participants did not correlate with STI diagnoses (r=- 0.16, p=0.747), number of sexual partners in her lifetime (r= -0.003, p=0.954), number of sexual partners in the previous three months (r= -0.016, p=0.751), communication with sexual partner regarding condom usage (r= -0.033, p=0.516), condom purchases(r=0.001, p=0.987), Papanicolau examination (r=-0.015, p=0.789), nor did it correlate with HIV testing rates (r= -0.005, p=0.92). No distinction was made regarding type of institution participants attended. From the results obtained, four main areas were identified to affect health-related preventive actions amongst the Chilean women interviewed including (1) Participants reported under-utilization of diagnostic exams, (2) Decreased use of condoms, (3) Cultural stigma towards HIV/AIDS and (4) Lack of continuity of care in women's health The next step for Chilean Public Health officials is to create public health programs and campaigns to increase population knowledge and understanding of HIV and AIDS. Secondary education must integrate information regarding safe sex practices into the curriculum. Future studies should investigate type of schooling attended (government-subsidized, semi-private, private), to determine variations in quality of education between socioeconomic status and the association with health-related preventive actions.

During the past decade, the Mexican government launched an ambitious expansion of public health insurance through the Seguro Popular programme (SP). As a result, health care access was legislated as citizens’ entitlement, a generous benefit package was offered, and public health expenditure was significantly increased. In 2011, the programme had reached 52 million affiliates. However, there is limited evidence on its effects on a number of outcomes and their distribution. This thesis analyses three aspects that are key to evaluate health system performance. Specifically, using quasi-experimental methods and recent distributional measures of pure health, it examines the effect of universal insurance coverage on infant mortality, non-medical consumption, and health inequalities. Drawing on municipality-level data, the first article finds that the programme led to a 3.9 per cent decrease in infant and neonatal mortality. These reductions were concentrated in more populated, urban, and less marginalised municipalities, however, probably because this type of municipalities have been traditionally better equipped and are thus better prepared to offer all the interventions from the benefit package. Based on data from the Mexican Family Life Survey (MxFLS), the second article shows that unexpected health events such as accidents and deterioration in physical capacity are associated with large declines in non-medical consumption. Social security seems to provide protection against both types of shocks, but endogeneity-corrected estimates show that the SP only protects consumption against accidents. This suggests that income losses associated with disability shocks for which the programme does not offer protection, are likely larger than medical care expenditures, and poses the question of whether other social security benefits, such as disability insurance, should also be extended. Finally, the third article analyses the distribution of health in the context of the SP implementation. Unlike traditional studies, pure health inequality and mobility are analysed using a recently developed class of indices appropriate for categorical data. If a downward-looking definition of status is employed, the distribution of health appears stable, but if an upward-looking definition is adopted, a significant increase in inequality is observed. Evidence of strong persistence in health was also found. This lack of improvement in the health distribution suggests that factors other than health insurance coverage, such as institutional performance, are more important determinants of health inequalities. Overall, this thesis finds important health effects from extending health insurance coverage but limited effects on economic welfare and the distribution of health status across the entire population.

Introduction: Current evaluation approaches for new medical technologies are problematic for a plethora of reasons relating to measuring their expected costs and consequences, but also due to hurdles in turning assessed information into coverage decisions. Most adopted methodologies focus on a limited number of value dimensions, despite the fact that the value of new medicines is multi-dimensional in nature. Explicit elicitation of social value tradeoffs is not possible and decision-makers may adopt intuitive or heuristic modes for simplification purposes, based on ad hoc procedures that might lead to arbitrary decisions. Objectives: The objective of the present thesis is to develop and empirically test a methodological framework that can be used to assess the overall value of new medical technologies by explicitly capturing multiple aspects of value while allowing for their tradeoffs, through the incorporation of decision-makers’ preferences in a structured and transparent way. The research hypothesis is that Multiple Criteria Decision Analysis (MCDA) can provide a methodological option for the evaluation of new medicines in the context of Health Technology Assessment (HTA), to support decision-making and contribute to more efficient resource allocation. Methods and Empirical Evidence: The first paper proposes a conceptual methodological process, based on multi-attribute value theory (MAVT) methods comprising five distinct phases, outlining the stages involved in each phase and discusses their relevance in the HTA context. The second paper conducts a systematic literature review and expert consultation in order to investigate the practices, processes and policies of value-assessment for new medicines across eight European countries and identifies the evaluation criteria employed and how these inform coverage recommendations as part of HTA. The third paper develops a MAVT value framework for HTA, incorporating a generic value tree for new medicines composed from different levels of criteria that fall under five value domains (i.e. therapeutic, safety, burden of disease, innovation and socio-economic), together with a selection of scoring, weighting and aggregating techniques. In the fourth and fifth papers, the value framework is tested empirically by conducting two real-world case studies: in the first, the value tree is adapted for the evaluation of second-line biological treatments for metastatic colorectal cancer (mCRC) patients having received prior oxaliplatin-based chemotherapy; in the second, the value tree is conditioned for the evaluation of third-line treatments for metastatic castrate resistant prostate cancer (mCRPC) patients having received prior docetaxel chemotherapy. Both case studies were informed by decision conferences with relevant expert panels. In the mCRC decision conference multiple stakeholders participated reflecting the composition of the English National Institute for Health and Care Excellence (NICE) technology appraisal committees, whereas in the mCRPC decision conference a group of evaluators participated from the Swedish Dental and Pharmaceutical Benefits Agency (TLV), thereby adopting the TLV decision-making perspective. Policy Implications: The value scores produced from the MCDA process reflect a more comprehensive benefit metric that embeds the preferences of stakeholders and decisionsmakers across a number of explicit evaluation criteria. The incorporation of alternative treatments’ purchasing costs can then be used to derive incremental cost value ratios based on which the treatments can be ranked on ‘value-for-money’ grounds, reflecting their incremental cost relative to incremental value. Conclusion: The MCDA value framework developed can aid HTA decision-makers by allowing them to explicitly consider multiple criteria and their relative importance, enabling them to understand and incorporate their own preferences and value trade-offs in a constructed and transparent way. It can be turned into a flexible decision tool for resource allocation purposes in the coverage of new medicines by payers but could also be adapted for other decision-making contexts along their development, regulation and use.

Worldwide, cardiovascular disease (CVD) is the leading cause of death. It is widely accepted that both active smoking and exposure to secondhand smoke (SHS) are associated with CVD. About 20% of the global population smoke tobacco or tobacco-related products. The global prevalence of smoking is increasing, although it is decreasing in some high-income and upper middle-income countries. Globally, about a third of adults and 40% children are regularly exposed to SHS. According to the World Health Organisation (WHO), only 16% of the global population is protected by a comprehensive smoke-free legislation. Coronary heart disease (CHD), stroke and peripheral arterial disease (PAD) are all types of atherosclerosis and often co-exist in the same patients. Therefore, they share many common risk factors including cigarette smoking. However, previous epidemiological studies on CVD including those on cigarette smoking mainly focused on CHD and stroke and pay little attention to PAD. Evidence is increasing in support of the association between exposure to SHS and both CHD and stroke. In contrast, there is a paucity of studies on SHS and the risk of PAD. The overarching aim of this thesis was to collate the published evidence on the association between active cigarette smoking and PAD, and examine the association between exposure to SHS and PAD in the general population. This thesis starts with a systematic review on the association between active cigarette smoking, SHS and PAD undertaken using four databases: Medline, Embase, PubMed and Web of Science to identify existing published evidence up to 30 April 2012 (Chapter 2). Prior to the published studies contained in this thesis, there had been no meta-analyses on the association between active cigarette smoking and PAD and only two studies published on the association between SHS and PAD. Therefore, this systematic review was followed by a meta-analysis on the association between active cigarette smoking and PAD. This meta-analysis identified 55 studies: 43 cross-sectional, 10 cohort and 2 case-control. Of the 68 results for current smokers, 59 (86.8%) were statistically significant and the pooled odds ratio (OR) was 2.72 (95% confidence interval [CI] 2.28-3.21). Of the 40 results for ex-smokers, 29 (72.5%) were statistically significant and the pooled OR was 1.67 (95% CI 1.54-1.81). Active cigarette smoking significantly increases the risk of PAD, compared with never smokers. The magnitude of association between active cigarette smoking and PAD was greater in current smokers than ex-smokers. In contrast, prior to my studies in this thesis, only two studies on SHS were identified. Only one showed an overall association between self-report SHS and PAD in Chinese never smokers, with a clear dose-response relationship. The other study used serum cotinine as measure for SHS exposure and found neither an overall association nor a dose-response relationship but suggested a very high cotinine concentration as threshold. Chapter 3 examines the association between SHS exposure and PAD in adult non-smokers in Scotland. This chapter includes two cross-sectional studies using the Generation Scotland: Scottish Family Health Study (GS: SFHS) and the Scottish Health Survey (SHeS), and one retrospective cohort study using the record linkage of the SHeS. In the cross-sectional study using SFHS, PAD was measured using ankle brachial pressure index (ABPI) but SHS exposure was self-report. Of the 5,686 never smokers, 134 (2.4%) had PAD (defined as an ABPI < 0.9). Participants who reported overall high level of SHS exposure (exposed to ≥40 hours per week) were more likely to have PAD, compared with those who reported no exposure to SHS. After adjustment for potential confounders, the association between SHS and PAD persisted (adjusted OR 4.53, 95% CI 1.51-13.56, p=0.007), with suggestion of a dose-response relationship. In the other cross-sectional study using SHeS, SHS exposure was measured objectively using cotinine concentration but PAD was based on self-report symptoms of intermittent claudication (IC) using the Edinburgh Claudication Questionnaire. Of the 4,231 non-smokers (defined as self-reported non-smokers with a salivary cotinine concentration <15 ng/mL), 134 (3.2%) had IC. Participants with high exposure to SHS (cotinine ≥2.7 ng/mL) were at significantly higher risk of IC, after adjustment for potential confounders (adjusted OR 1.76, 95% CI 1.04-3.00, p=0.036). A dose-response relationship was suggested, whereby the risk of IC increased with increasing cotinine concentration. However, the association varied by age category. Participants aged <60 were more strongly associated with PAD. This may be explained by survival bias. For the third, retrospective cohort study in Chapter 3, I used record linkage of SHeS to Scottish Morbidity Record 01 (SMR01) records and death certificates to identify the first hospital admission/death following the SHeS in which PAD was recorded as the primary or secondary cause. Of the 4,045 confirmed non-smokers who were free of baseline IC were included. Over the follow-up period (mean follow-up 9 years), there were 568 deaths, none of which were coded as due to PAD, and 64 participants were hospitalised for PAD. High exposure to SHS was associated with increased risk of all-cause mortality (adjusted hazard ratio [HR] 1.42, 95% CI 1.09- 1.86, p=0.011) among all non-smokers and increased risk of incident PAD (adjusted HR 2.82, 95% CI 1.14-6.96, p=0.024) among male non-smokers. Increased cotinine concentrations at baseline were associated with increased risk of all-cause mortality, with a dose-response relationship. SHS contains both sidestream smoke, from burning cigarette tips, and exhaled mainstream smoke. Shortened telomere length is broadly viewed as a biomarker for biological ageing including atherosclerosis phenotypes such as PAD. Evidence is strong that active smoking increases telomere length attrition but whether such association occurs between SHS and telomere length is unknown. Therefore, Chapter 4 aimed to add to growing evidence that exposure to SHS is associated with disproportionately higher biomarkers of cardiovascular risk compared with active smoking and may accelerate normal biological ageing. This chapter includes two cross-sectional studies. The first study investigated the relationship between salivary cotinine and several preclinical cardiovascular biomarkers: C-reactive protein (CRP), high-density lipoprotein (HDL) cholesterol, TC/HDL cholesterol ratio and fibrinogen in 10,081 adults from the SHeS. CRP concentration and the TC/HDL cholesterol ratio increased, and HDL cholesterol concentration decreased with increasing cotinine concentration among both non-smokers and active smokers. There were step changes in the relationship between tobacco exposure and cardiovascular biomarkers at the interface of non-smokers exposed to SHS and active smokers. Non-smokers with high exposure to SHS had lower cotinine concentrations than light active smokers but comparable concentrations of CRP (p=0.709), HDL cholesterol (p=0.931) and the TC/HDL cholesterol ratio (p=0.405). Fibrinogen concentration was less clear-cut and only increased in moderate and heavy active smokers. The second study in this chapter explored the association between self-reported levels of SHS exposure and telomere shortening per annum using a subgroup of participants from the SFHS. Of the 1,303 non-smokers, telomere length decreased more rapidly with increasing age among participants with high level of SHS exposure, compared with both those with no exposure (adjusted coefficient -0.006, 95% CI -0.008- -0.004) (high vs no SHS: p=0.010) or low exposure (adjusted coefficient -0.005, 95% CI -0.007- -0.003) (high vs low SHS: p=0.005). In summary, there is now substantial evidence of an association between active cigarette smoking and PAD. / This thesis adds to the limited existing evidence on SHS as an independent risk factor for PAD. There was an overall association between exposure to SHS and PAD, with suggestion of a dose-response relationship. However, the association varied by age category. Individuals aged <60 were more strongly associated with the prevalence of IC. SHS was significantly associated with incident PAD only in men. This thesis further demonstrates that exposure to SHS carries a disproportionately higher cardiovascular risk than active smoking for a given level of smoke exposure. Telomere shortening per year of age may be an intermediate step between SHS and CVD including PAD. This also supports the association between SHS exposure and the atherosclerosis-related biomarkers, which play an important role in the pathophysiology of PAD. Further research is needed in the future to better understand the association between SHS and PAD, and the underlying mechanisms. The research in this thesis supports the need to protect the general public from exposure to SHS.

This study aims to describe the living and informal care circumstances of older people in an area of rural South Africa severely affected by HIV, and examine how those circumstances may influence the physical health, emotional well-being and survival of older people. Using longitudinal surveillance and cross-sectional survey data this thesis is built around four separate but related papers. Specific study objectives were to: 1) investigate household living arrangements and informal care (financial, physical or emotional assistance) by or towards older people in rural South Africa; 2) describe the self-reported health and emotional well-being status of older people by HIV status; and 3) examine the association between self-reported health, emotional well-being and informal care and mortality in older people. Surveillance data for 2005-2010 showed living arrangements remained stable, with over 85% of older people aged 60 years and above living in multi-generational households; over this period employment rates in both older and young people declined, but government grants receipt increased. Being co-resident with own children, household structure and size were important determinants of whether financial support flowed downward (from older to younger) or upward (from young to older person); while peer support (from one older person to another) was rare. Adjusting for age, marital status, education, place of residency and household socio-economic status, exchanges of financial resources in the study population are most likely to be downward or at best reciprocal (bidirectional with young people). Of the cross-sectional study participants (n=422) aged 50+, over 60% were care-givers (provided help with activities of daily living) to at least one adult (18-49 years) or child (below 18 years); around 84% (n=356) of older people were care-receivers; of whom over 92% (n=329) were receiving assistance with fetching water. Spouse, adult child, and grandchildren were the main sources of physical or emotional care for care-recipients. As expected health deteriorated with advancing age and women were less likely to be in good health. Further, care-giving was associated with improved functional ability but decreased emotional well-being. HIV-infected older participants reported better functional ability, quality of life and overall health state than HIV-affected (had an HIV-infected or HIV-related death of adult child) study participants. These differentials in health and well-being were also evident in mortality patterns over three years of follow-up. Mortality was higher among non-care-givers than in care-givers, in older people with poor self-rated health and in participants who had experienced a major depressive episode. Findings suggest there is an intricate relationship between living arrangements, informal care and health, emotional well-being and survival of older people in severely HIV-affected settings. More crucially, with the considerable resources devoted to HIV Care and Treatment programmes, uninfected older persons may be highly vulnerable to poor health. A multifaceted intervention to improving older people’s health and well-being is urgently required.

Hand hygiene is considered the cornerstone of infection prevention practice, but previous studies demonstrate one group of healthcare professionals, doctors, have not achieved good levels of compliance in comparison to other staff groups. The aim of the research was to examine consultant doctors‟ practice and perspectives of hand hygiene, exploring their perceptions as leaders and role models, so as to identify strategies to improve compliance. The study design was based on naturalistic inquiry, focussing on the social constructions of participants. Nineteen consultant doctors were observed during hospital ward rounds using both a national audit tool to assess hand hygiene compliance and recording of field notes. These same consultants, plus a further two, were interviewed individually to elicit their views. Data from the 21 interviews and field notes were analysed qualitatively using thematic content analysis. Observations demonstrated high levels of hand hygiene compliance for high risk and medium risk activities, with low levels of compliance for low risk activities. Thematic content analysis revealed a strong belief by consultant doctors in the value of hand hygiene. However, a perceived conflict between political and scientific drivers of hand hygiene promotion gave rise to confusion, frustration and a lack of engagement that created barriers to leadership and acting as a role model. Differing guidelines and audit tools that did not address levels of risk compounded the matter. However, consultant doctors offered various recommendations to resolve the issues. Compliance with hand hygiene by consultant doctors is dependant on perceived levels of risk. To promote leadership and role modelling it is critical to engage consultant doctors, understand their views, employ their recommendations and recognise they are motivated by evidence-based rationales for practice rather than political mandates. The findings, conclusion and recommendations of the research study have significant implications for addressing the shortfalls of the hand hygiene agenda in clinical practice and for the engagement of consultant doctors.

Cochlear implants (CI) provide a sense of hearing to people who are severely or profoundly deaf. A single CI (unilateral) has been shown to improve quality of life (QoL) substantially and clinical practice is evolving towards two per patient (bilateral), although the incremental benefit for QoL has not yet been established definitively. There is a need for self-report measures designed specifically to quantify benefits for QoL in patients who receive a second CI, in order to evaluate the relative benefits of unilateral and bilateral implantation. The aim of the present study was to develop and validate such a measure that is suitable for adults. The sample consisted of patients from the United Kingdom National Health Service who have received two CI sequentially. The study was based on the ‘Rolls Royce’ approach. A retrospective open-ended questionnaire and face to face interviews were carried out in the first stage. Categories from the qualitative data obtained from the responses were identified and these were the foundations on which a close-ended questionnaire was developed. In the second stage, face validity, test-retest reliability and correlations of each item were investigated and amendments were made to the questionnaire items to reflect these results. In the last stage participants were asked to fill in the amended questionnaire together with another three existing QoL questionnaires (generic and disease-specific ones). These results showed that the questionnaire under development is valid and reliable. Responses from the participants also gave an insight into the changes that they experienced as a result of receiving a second CI. The main reports were related to experiences of increased confidence and independence levels as a result of having bilateral CI. Improvement in listening in group situations and localisation ability were also noted. Changes in participant experience were evident when they filled in the questionnaire under development and also the Speech, Spatial and Qualities of Hearing questionnaire. Better understanding of changes in QoL after receiving a second CI will help professionals to understand the benefits of bilateral implantation in adults from the users’ perspectives. This is considered to be important when deciding whether patients should be advised to opt for unilateral or bilateral CI in the future. This knowledge will also help prospective patients understand the practical benefits and limitations of one or two cochlear implants.

This thesis is concerned with the modelling of patient length of stay in public hospitals in Mexico. Patient length of stay is the most commonly worldwide employed outcome measure for hospital resource consumption and performance monitoring. Most of the hospitals around the world use average length of stay as starting point for resource planning. However average estimates frequently gives non-accurate results due to the high variability of the length of stay data. The reason for such high variability may be attributable to the diversity in the patient population and the environment where the patient is treated. Through a systematic review of the literature on methods and models in the field of calculating and predicting patient length of stay, this research highlights the areas of opportunity and research gap from previous studies and practices, and proposes the use of finite mixture models to approximate the distribution of length of stay. Also, these models are proposed as the foundation of more sophisticated models designed to include the internal and external factors associated with LoS. In this context, the thesis proposes three different approaches to explore such factors: individual-based approach, group-based approach and multilevel group-based approach. These interrelated approaches allow a better understanding of the diversity in the patient population and enable length of stay predictions for individual patients, and for cohorts of patients within and between hospitals. In addition, this research is built and evaluated using data from all types of patients treated at two public hospitals operating in Mexico. It is the consideration of the full case-mix of these healthcare facilities that gives this research its unique nature.