Edgar Samarasundera

Variations in cardiovascular disease under-diagnosis in England: national cross-sectional spatial analysis

BackgroundThere is under-diagnosis of cardiovascular disease (CVD) in the English population, despite financial incentives to encourage general practices to register new cases. We compared the modelled (expected) and diagnosed (observed) prevalence of three cardiovascular conditions- coronary heart disease (CHD), hypertension and stroke- at local level, their geographical variation, and population and healthcare predictors which might influence diagnosis.MethodsCross-sectional observational study in all English local authorities (351) and general practices (8,372) comparing model-based expected prevalence with diagnosed prevalence on practice disease registers. Spatial analyses were used to identify geographic clusters and variation in regression relationships.ResultsA total of 9,682,176 patients were on practice CHD, stroke and transient ischaemic attack, and hypertension registers. There was wide spatial variation in observed: expected prevalence ratios for all three diseases, with less than five per cent of expected cases diagnosed in some areas. London and the surrounding area showed statistically significant discrepancies in observed: expected prevalence ratios, with observed prevalence much lower than the epidemiological models predicted. The addition of general practitioner supply as a variable yielded stronger regression results for all three conditions.ConclusionsDespite almost universal access to free primary healthcare, there may be significant and highly variable under-diagnosis of CVD across England, which can be partially explained by persistent inequity in GP supply. Disease management studies should consider the possible impact of under-diagnosis on population health outcomes. Compared to classical regression modelling, spatial analytic techniques can provide additional information on risk factors for under-diagnosis, and can suggest where healthcare resources may be most needed.

Prevalence of cardiovascular disease risk amongst the population eligible for the NHS Health Check Programme

Background: The National Health Service (NHS) Health Check Programme aims to identify and manage patients in England aged 40–74 years with a 10-year cardiovascular disease (CVD) risk score over 20%. We aimed to assess the prevalence of high CVD risk in the English population, using the two CVD risk scores and the 20% cut off mandated in national policy, and the prevalence of risk factors within this population. Design: Modelling study using patients registered in general practice in England. Methods: Using data from the Health Survey for England, we modelled the prevalence of high CVD risk in general practice populations. Results: Of those eligible for an NHS Health Check, 10.5% (2,012,000) had a risk score greater than 20% using the QRISK2 risk score; 22.0% (4,267,000) using Joint British Societies’ (JBS2) score. There was a median of 206 (range 0–1693) and 447 (0–3321) patients per practice at high risk respectively, with wide geographic variation. Within the high-risk population, there was a high prevalence of CVD risk factors; in the QRISK2 population, for example 82.6% were physically inactive. To reduce risk in those at high CVD risk, we estimate the total costs of the Programme to be £176 million using QRISK2 or £378 million using JBS2. Conclusions: A large number of high-risk patients will be identified by the Programme; health service commissioners must ensure the adequate provision and the targeted allocation of risk reduction services for the Programme to be effective. The NHS must consider whether extra costs using JBS2 are warranted. The Programme must be fully monitored to ensure its cost effectiveness and appropriate outcomes such as the numbers at high risk assessed.

Mapping mental health service access: achieving equity through quality improvement

BACKGROUND Improving access to psychological therapies (IAPTs) services deliver evidence-based care to people with depression and anxiety. A quality improvement (QI) initiative was undertaken by an IAPT service to improve referrals providing an opportunity to evaluate equitable access. METHODS QI methodologies were used by the clinical team to improve referrals to the service. The collection of geo-coded data allowed referrals to be mapped to small geographical areas according to deprivation. RESULTS A total of 6078 patients were referred to the IAPT service during the period of analysis and mapped to 120 unique lower super output areas (LSOAs). The average weekly referral rate rose from 17 during the baseline phase to 43 during the QI implementation phase. Spatial analysis demonstrated all 15 of the high deprivation/low referral LSOAs were converted to high deprivation/high or medium referral LSOAs following the QI initiative. CONCLUSION This work highlights the importance of QI in developing clinical services aligned to the needs of the population through the analysis of routine data matched to health needs. Mapping can be utilized to communicate complex information to inform the planning and organization of clinical service delivery and evaluate the progress and sustainability of QI initiatives.

Interactive map communication: pilot study of the visual perceptions and preferences of public health practitioners

OBJECTIVES To conduct a pilot study into the comprehension and visualisation preferences of geographic information by public health practitioners (PHPs), particularly in the context of interactive, Internet-based atlases. STUDY DESIGN Structured human-computer interaction interviews. METHODS Seven academia-based PHPs were interviewed as information service users based on a structured questionnaire to assess their understanding of geographic representations of morbidity data, and identify their visualisation preferences in a geographic information systems environment. RESULTS Awareness of area-based deprivation indices and the Index of Multiple Deprivation 2007 health and disability domain was near-universal. However, novice users of disease maps had difficulties in interpreting data classifications, in understanding supplementary information in the form of box plots and histograms, and in making use of links between interactive tabular and cartographic information. Choices for colour plans when viewing maps showed little agreement between users, although pre-viewing comments showed preferences for red-blue diverging schema. CONCLUSIONS PHPs new to geographic information would benefit from enhanced interpretive support documentation to meet their needs when using Internet-based, interactive public health atlases, which are rarely provided at such sites. Technical, software-related support alone is insufficient. Increased interaction between PHPs and mapmakers would be beneficial to maximise the potential of the current growth in interactive, electronic atlases, and improve geographic information support for public health decision-making and informing the wider public.

Methods and tools for geographical mapping and analysis in primary health care

AIM The purpose of this paper is to review methods and tools for mapping, visualising and exploring geographic information to aid in primary health care (PHC) research and development. BACKGROUND Mapping and spatial analysis of indicators of locality health profiles and healthcare needs assessment are well-established facets of health services research and development. However, while there are a range of different methods and tools used for these purposes, non-specialists responsible for managing the use of such information systems may find knowing where to start and what can be done a relatively steep learning curve. In this review, health and sociodemographic datasets are used to illustrate some key methods, tools and organisational issues, and builds upon two recent reviews in this journal, respectively, focusing on geographic data sources and geographic concepts. Those familiar with mapping and spatial analysis should find this a useful review of current matters. METHOD A thematic review is presented with illustrative case studies relevant to PHC. It begins with a section on visualising and interpreting geographic information. This is followed by a section critiquing analytical methods. Consideration is given to software and deployment issues in a third section. Content is based on domain knowledge of the authors as a team of geographic information scientists and a public health practitioner working in tandem, with its scope restricted to routine applications of mapping and analysis. Advanced techniques such as spatio-temporal modelling are not considered, neither are methodological technicalities, although guidance on further reading is provided. SUMMARY Geographical perspectives are now playing a significant role in PHC delivery, and for those engaged in informatics and/or managing population-level care, understanding key geographic information systems methods and terminologies are important as is gaining greater familiarity with institutional aspects of implementation.

Geological hazards: From early warning systems to public health toolkits

Extreme geological events, such as earthquakes, are a significant global concern and sometimes their consequences can be devastating. Geographic information plays a critical role in health protection regarding hazards, and there are a range of initiatives using geographic information to communicate risk as well as to support early warning systems operated by geologists. Nevertheless we consider there to remain shortfalls in translating information on extreme geological events into health protection tools, and suggest that social scientists have an important role to play in aiding the development of a new generation of toolkits aimed at public health practitioners. This viewpoint piece reviews the state of the art in this domain and proposes potential contributions different stakeholder groups, including social scientists, could bring to the development of new toolkits.

Attendance for injury at accident and emergency departments in London: a cross-sectional study.

OBJECTIVE In order to set the foundation for the possible development of injury surveillance initiatives in north-west London, data on all presentations during 2002 at the nine accident and emergency departments (AEDs) in the relevant strategic health authority were examined. STUDY DESIGN Descriptive, cross-sectional study. METHODS A search algorithm was devised to extract records pertaining to injury presentations. The results were validated against a manually checked sample. Descriptive, quantitative analyses were performed. RESULTS Only four of the nine hospitals in the study area routinely recorded data in a form useful for research on injury. In these four hospitals, presentations with injury accounted for 29.7% of total attendances at the AED, which is markedly lower than the national average. CONCLUSIONS Certain characteristics of London regarding provision of primary care may explain why attendances for injury are proportionately low. However, the unusual pattern also underlines the importance of improving the quality of AED data in order to support adequate local surveillance of injury as the basis of efforts to prevent such incidents and to plan services to deal with injuries.

Socio-demographic data sources for monitoring locality health profiles and geographical planning of primary health care in the UK

Aim: the aim of this article is to provide UK-based primary health care research and development workers with a review of the current range of published, aggregated socio-demographic indicators that can be combined with health and health care datasets, for the purposes of monitoring locality health profiles and planning primary health care. Non-UK readers should nevertheless find the review of some relevance to their own national contexts. Background: there is an increasing range of resources available for such purposes and many of these datasets are equally useful outside of geographic work. The 2001 census introduced important changes to what routine data are available, as will the 2011 census. These changes have been paralleled by developments in the availability of socio-demographic indicators and the increasing popularity of geographic information systems. Health data can now be combined with those from socio-demographic more efficiently to produce what are termed value-added datasets. Methods: we review recent and planned developments in key data sources currently available in the UK and examine they can be used to monitor inequalities in primary health care inequalities and their role in the integration of primary health care needs mapping and forecasting with the spatial planning of areas undergoing regeneration. Conclusions: recent and planned developments in the availability of both socio-demographic datasets in tandem with parallel developments in spatial technologies have provided a flexible, potent geographical methodology for primary health care research and development. The current consultation process for the 2011 census provides those involved with primary health care research and development an opportunity to influence future developments