Light on population health status.

A new approach to illustrating and analysing health status is presented which allows comparisons of various aspects of health in a population at different times and in different populations during given periods. Both quantitative and qualitative elements can be represented, the impact of interventions can be monitored, and the extent to which objectives are achieved can be assessed. The practical application of the approach is demonstrated with reference to the health profiles to Tunisia in 1966 and 1994.

PIP: In response to a World Health Organization's Global Advisory Committee on Health Research initiative, a "visual health information profile" was developed that provides a quantitative description of and an assessment of multidimensional aspects of health in a population. The profile uses a hierarchy of indicators, with first-level domains covering: 1) disease conditions and health impairments, 2) the health care system, 3) sociocultural characteristics, 4) environmental determinants, and 5) food and nutrition. Indicators at all levels can be disaggregated. A decile reference method can be used to display indicators by country and to rank performance for specific years, thus allowing country and time comparisons. The circular visual health information profile has radial sectors representing health domains (with sectors representing the indicators in each domain). Scaling is arranged so that situations needing urgent attention are displayed on the periphery. With fixed reference points, comparisons can be made over time. A prototype of this profile is available via the World Wide Web at http://faw.uni-ulm.de/planet/health-profile/circle.html. The profile was evaluated by superimposing indicators for Tunisia for 1994 over those for 1966. Because of the immediate impact of the visual display of information, the profile, which can be applied to indicators at various levels, can contribute to the improvement of public health.

Telematics in research planning processes: an example from global health.

It is increasingly recognized that the appropriate application of information and communication technology can substantially improve communication and cooperative work processes in terms of quantity, quality and cost-effectiveness. Within large organizations, strategic decision making is one of the key cooperative processes which have to be faced. In this paper the authors discuss one example of this class of cooperative processes: research planning within the World Health Organization (WHO). The paper presents conceptual details of a process designed to assist in creating global networks of scientists, planners and field workers interested in cooperating to promote health development activities of WHO. The implementation of this process was realized in an Internet-based system to support global research planning. In particular, this application shows that the utilization of information and communication technology can not only quantitatively change existing processes, but can create new ones--and on a qualitatively improved level.

Visual Health Information Profile (VHIP). A quantitative approach for analysing the health status of a population.

A new approach for illustrating and analysing the health status of a given population is presented. The concept takes the multi-dimensional nature of health into account. It is based on a clearly out-lined indicator hierarchy, a decile reference system and a computerised information system. The instrument displays the health status of a population and allows comparisons to be made of various health aspects for a given population at different times and allows comparisons to be made of different populations during given time periods. It is possible to represent quantitative and qualitative aspects of health, to monitor the impact of interventions, and to assess the extent to which objectives in the health field have been achieved. Therefore, it can serve as an instrument for communication between policy makers and scientists to manage and to co-ordinate programs that aim at an improvement of the health status and to assist in the priority setting process. The method was applied to several countries using the World Health Organisation's (WHO) "Health For All Global Indicator Database" as the main data source. Country and region specific health status patterns could be generated showing the practicability of the approach. Using a computerised information system, a high degree of transparency and flexibility with respect to the input data and the choices of measurables was achieved.

Telehealth: the delayed revolution in health care.

It is recognized that health care in rural communities could be improved significantly with the assistance of telehealth, the term by which the combined application of computer and telecommunications technologies to health care has come to be known. Yet in spite of its obvious potential, the telehealth literature has shown a surprising lack of growth. This paper reports an analysis which revealed that, between 1975 and 1990, few telehealth articles were catalogued by the National Library of Medicine, and suggests why this might have been the case. Following a brief discussion of the origins of telehealth, terminology, and the rural health care crisis, this overview examines the status of telehealth in terms of its main applications: telemedicine and tele-education. An analysis of the pattern of publications between 1975 and 1990 is then used to suggest why telehealth has not fulfilled its potential. Corrective measures are proposed and the paper concludes with a summary of recent telehealth initiatives.

Digital diagnostic imaging with a comprehensive PACS: hypothetical economic evaluation at a large community hospital.

Since 1983, the 422-bed Victoria General Hospital (VGH) and Siemens Electric Limited have been piloting the implementation of digital medical imaging, including digital acquisition of diagnostic images, in British Columbia. Although full PACS is not yet in place at VGH, experience to date has been used to project annual cost figures (including capital replacement) for a fully digital department. The resulting economic evaluation has been labeled hypothetical to emphasize that some key cost components were estimated rather than observed; this paper presents updated cost figures based on recent revisions to proposed departmental equipment configuration. Compared with conventional diagnostic imaging, digital imaging appears to raise overall annual costs at VGH by nearly $0.7 million, (Canadian currency) or 11.6%; this is more favorable than the previous results, which indicated extra annual costs of $1 million (16.9%). Sensitivity analysis still indicates that all reasonable changes in the underlying assumptions result in higher costs for digital imaging than for conventional imaging. Digital imaging appears likely to offer lower radiation exposure to patients, shorter waiting times, and other potential advantages, but as yet the price of obtaining these benefits remains substantial.

Digital chest imaging using a 57-cm image intensifier: a receiver-operating characteristic study of user performance.

Chest radiography provides one of the great challenges to digital diagnostic imaging because of (1) the relatively large size of the chest field, (2) the contrast range required to resolve subtle pathological changes in soft tissue density, and (3) the high degree of spatial resolution required to discriminate pathological detail. The field size problem was resolved by using a 57-cm image intensifier whose video output of the chest could be digitized. The issue of contrast resolution was addressed in a recently completed receiver-operating characteristic study of the detectability of low-contrast densities in a humanoid chest phantom. The latter indicated that, despite the smaller size of the digital image, they were adequate for resolving clinically significant soft-tissue densities. The question of spatial resolution in digital diagnostic images is addressed in the study presented. A set of 41 clinical cases were selected to provide the typical range of diagnostic type experienced in routine diagnostic radiology. The images were each presented as conventional film, digital laser-printer, and digital video images. The results of an ROC analysis of five readers' performance in each of the viewing modes is presented.

Impact of image size on effectiveness of digital imaging systems.

Radiologists detect small diagnostic signals in radiographic film images by altering the distance between the eye and the image, effectively zooming in on a particular detail. Details thus enlarged are more perceptible to the viewer. Considering that conventional film images are nearly life-size, the potential for increasing the detection of small signals in this manner is high. Digital images, however, presented in video format are usually smaller than life-size, sometimes more than 50% smaller. While local enlargements using computer-based imaging systems are extremely useful, the radiologist cannot examine a whole, life-size image. The importance of the latter in the diagnostic process is revealed in detection studies using the same images of a chest phantom with small nodular inclusions, in different size formats. A clear positive correlation exists between overall image size and the detection of signals that are of a diagnostically-relevant size. While it is widely accepted that image fidelity is an important determinant in the clinical acceptability of digital radiography, digital image displays should also be large enough to display life-size images.

Signal detection in digital chest-phantom images acquired with an image intensifier.

Signal detection performance was evaluated on the basis of ROC analysis using both digital and conventional images of a humanoid chest phantom. Simulated focal (coin) lesions were the target pathology. Digital images were acquired using a 57-cm image intensifier, digitized to 1024 x 1024 x 10 bits, and compared, in both video and laser-printed film formats, with conventional 14 x 17-inch chest films. Signal detection using digital video and laser printed images, of the same image polarity as conventional images, was found not to differ significantly from that achieved using conventional images, despite the smaller size of the digital images.

A prospective study of gout in New Zealand Maoris.

Results are reported from the first prospective study of gout in New Zealand Maoris based on a sample of 388 males and 378 females. At baseline, high mean levels of serum uric acid (SUA) were found, 0.422 +/- 0.092 mmol/1 (7.05 +/- 1.54 mg/100 ml) in males and 0.350 +/- 0.091 mmol/1 (5.85 +/- 1.52 mg/100 ml) in females. On the basis of traditional criteria (SUA above 0.42 mmol/1 (7.0 mg/100 ml) in males and above 0.36 mmol/1 (6.0 mg/100 ml) in females) the prevalence of hyperuricaemia was 49% in males and 42% in females. The baseline prevalence of gout (8.8% for males and 0.8% for females) and the subsequent 11-year incidence rates (10.3% for males and 4.3% for females) are discussed in relation to specified SUA classes. When traditional, sex-specific criteria for hyperuricaemia were used, no relationship was found between the prevalence of hyperuricaemia and the incidence of gout. There was, however, a sharp increase in the incidence rate of gout in both sexes when SUA levels were above 0.48 mmol/1 (8.0 mg/100 ml). In subjects with a baseline SUA above this level, the age-standardised 11-year incidence rate of gout was 29.1% for males and 37.2% for females. A previously unreported relationship linking muscle size to the incidence of gout in males is presented as a major finding of the study. Other risk factors associated with gout were body mass and blood pressure.