Teledermatology can produce high-quality care at low cost

Teledermatology can provide both accurate and reliable specialist care at a distance. This article reviews current data on the quality of care that teledermatology provides, as well as the societal cost benefits involved in the implementation of the technique. Teledermatology is most suited to patients unable to access specialist. services for geographical or social reasons. Patients are generally satisfied with the overall care that teledermatology provides. Real-time teledermatology is more expensive than conventional care for health services. However, significant savings can be expected from the patient's perspective due to reduced travel. Appropriate patient selection, improved technology and adequate clinical workloads may improve both the quality and cost effectiveness of this service.

A review of telemedicine and asthma

The literature contains a number of reports of early work involving telemedicine and chronic disease; however, there are comparatively few studies in asthma. Most of the telemedicine studies in asthma have investigated the use of remote monitoring of patients in the home, e.g. transmitting spirometry data via a telephone modem to a central server. The primary objective of these studies was to improve management. A secondary benefit was that patient adherence to prescribed treatment is also likely to be improved. Early results are encouraging; home monitoring in a randomized controlled trial in Japan significantly reduced the number of emergency room visits by patients with poorly controlled asthma. Other studies have described the cost-benefits of a specialist asthma nurse who can manage patients by telephone contact, as well as deliver asthma education. Many web-based systems are available for the general public or healthcare professionals to improve education in asthma, although their quality is highly variable. The work on telemedicine in asthma clearly shows that the technique holds promise in a number of areas. Unfortunately - as in telemedicine generally - most of the literature in patients with asthma refers to pilot trials and feasibility studies, with short-term outcomes. Large-scale, formal research trials are required to establish the cost effectiveness of telemedicine in asthma.

Toward better outcomes with tacrolimus therapy: Population pharmacokinetics and individualized dosage prediction in adult liver transplantation

Patient outcomes in transplantation would improve if dosing of immunosuppressive agents was individualized. The aim of this study is to develop a population pharmacokinetic model of tacrolimus in adult liver transplant recipients and test this model in individualizing therapy. Population analysis was performed on data from 68 patients. Estimates were sought for apparent clearance (CL/F) and apparent volume of distribution (V/F) using the nonlinear mixed effects model program (NONMEM). Factors screened for influence on these parameters were weight, age, sex, transplant type, biliary reconstructive procedure, postoperative day, days of therapy, liver function test results, creatinine clearance, hematocrit, corticosteroid dose, and interacting drugs. The predictive performance of the developed model was evaluated through Bayesian forecasting in an independent cohort of 36 patients. No linear correlation existed between tacrolimus dosage and trough concentration (r(2) = 0.005). Mean individual Bayesian estimates for CL/F and V/F were 26.5 8.2 (SD) L/hr and 399 +/- 185 L, respectively. CL/F was greater in patients with normal liver function. V/F increased with patient weight. CL/F decreased with increasing hematocrit. Based on the derived model, a 70-kg patient with an aspartate aminotransferase (AST) level less than 70 U/L would require a tacrolimus dose of 4.7 mg twice daily to achieve a steady-state trough concentration of 10 ng/mL. A 50-kg patient with an AST level greater than 70 U/L would require a dose of 2.6 mg. Marked interindividual variability (43% to 93%) and residual random error (3.3 ng/mL) were observed. Predictions made using the final model were reasonably nonbiased (0.56 ng/mL), but imprecise (4.8 ng/mL). Pharmacokinetic information obtained will assist in tacrolimus dosing; however, further investigation into reasons for the pharmacokinetic variability of tacrolimus is required.

Telemedicine - the way ahead for medicine in the developing world

An e-mail link with the facility to send high-resolution digital images is a cheap and uncomplicated telemedicine method. The Swinfen Charitable Trust helped establish such a link in Patan Hospital Kathmandu, Nepal in March 2000. Over 12 months using this link 42 telemedicine referrals were sent to specialists throughout the world. Referrals were: 36% respiratory medicine; 21% neurology, 21% dermatology; 14% cardiology; 5% nephrology; and 3% radiology - 28 had digital pictures attached, of which 96% were of high enough quality on which specialists were able to comment. Thirty-nine replies were received. The average time for a specialist reply was 2 days, and 45% were answered within 24 hours. All replies were judged by independent assessors to be helpful or very helpful for diagnosis, management and education. The assessors decided that in 50% of cases the advice if acted upon would have shortened hospital stay. This pilot study has shown that a low-cost telemedicine link is technically feasible and can be of significant benefit for diagnosis, management and education in a developing world setting.

Modelling inpatient length of stay by a hierarchical mixture regression via the EM algorithm

The modelling of inpatient length of stay (LOS) has important implications in health care studies. Finite mixture distributions are usually used to model the heterogeneous LOS distribution, due to a certain proportion of patients sustaining-a longer stay. However, the morbidity data are collected from hospitals, observations clustered within the same hospital are often correlated. The generalized linear mixed model approach is adopted to accommodate the inherent correlation via unobservable random effects. An EM algorithm is developed to obtain residual maximum quasi-likelihood estimation. The proposed hierarchical mixture regression approach enables the identification and assessment of factors influencing the long-stay proportion and the LOS for the long-stay patient subgroup. A neonatal LOS data set is used for illustration, (C) 2003 Elsevier Science Ltd. All rights reserved.

Prospective evaluation of a D-optimal designed population pharmacokinetic study

Recently, methods for computing D-optimal designs for population pharmacokinetic studies have become available. However there are few publications that have prospectively evaluated the benefits of D-optimality in population or single-subject settings. This study compared a population optimal design with an empirical design for estimating the base pharmacokinetic model for enoxaparin in a stratified randomized setting. The population pharmacokinetic D-optimal design for enoxaparin was estimated using the PFIM function (MATLAB version 6.0.0.88). The optimal design was based on a one-compartment model with lognormal between subject variability and proportional residual variability and consisted of a single design with three sampling windows (0-30 min, 1.5-5 hr and 11 - 12 hr post-dose) for all patients. The empirical design consisted of three sample time windows per patient from a total of nine windows that collectively represented the entire dose interval. Each patient was assigned to have one blood sample taken from three different windows. Windows for blood sampling times were also provided for the optimal design. Ninety six patients were recruited into the study who were currently receiving enoxaparin therapy. Patients were randomly assigned to either the optimal or empirical sampling design, stratified for body mass index. The exact times of blood samples and doses were recorded. Analysis was undertaken using NONMEM (version 5). The empirical design supported a one compartment linear model with additive residual error, while the optimal design supported a two compartment linear model with additive residual error as did the model derived from the full data set. A posterior predictive check was performed where the models arising from the empirical and optimal designs were used to predict into the full data set. This revealed the optimal'' design derived model was superior to the empirical design model in terms of precision and was similar to the model developed from the full dataset. This study suggests optimal design techniques may be useful, even when the optimized design was based on a model that was misspecified in terms of the structural and statistical models and when the implementation of the optimal designed study deviated from the nominal design.

Organizational aspects of e-referrals

Three different, well established systems for e-referral were examined. They ranged from a system in a single country handling a large number of cases (60,000 per year) to a global system covering many countries which handled fewer cases (150 per year). Nonetheless, there appeared to be a number of common features. Whether the purpose is e-transfer or e-consultation, the underlying model of the e-referral process is: the referrer initiates an e-request; the organization managing the process receives it, the organization allocates it for reply; the responder replies to the initiator. Various things can go wrong and the organization managing the e-referral process needs to be able to track requests through the system; this requires various performance metrics. E-referral can be conducted using email, or as messages passed either directly between computer systems or via a Web-link to a server. The experience of the three systems studied shows that significant changes in work practice are needed to launch an e-referral service successfully. The use of e-referral between primary and secondary care improves access to services and can be shown to be cost-effective.

A national survey of telehealth activity in Australian hospitals

We conducted a national survey of Australian hospitals to assess their use of telehealth. Information was sought from the 814 hospitals with 10 or more beds, excluding the small number that provided only day surgery and seven for which we could not identify a contact person. A total of 564 replies were received (a 69% response rate). Nationally, nearly half (49%) reported that they were engaged in some telehealth activity. However, there was a significant difference across jurisdictions. Hospitals in the public sector were significantly more likely to report the use of telehealth than those in the private sector (62% vs 14%). Hospital remoteness was measured according to the Accessibility/Remoteness Index of Australia (ARIA). The highest levels of use were reported by hospitals in 'very remote' and 'remote' areas (90% and 88%, respectively), with moderate levels of use in 'moderately accessible' and 'accessible' areas (67% and 52%, respectively) and the lowest level of use in 'highly accessible' areas (35%). This trend was significant.

A review of the first year's experience with an automatic message-routing system for low-cost telemedicine

The Swinfen Charitable Trust has used email for some years as a low-cost telemedicine medium to provide consultant support for doctors in developing countries. A scalable, automatic message-routing system was constructed which automates many of the tasks involved in message handling. During the first 12 months of its use, 1510 messages were processed automatically. There were 128 referrals from 18 hospitals in nine countries. Of these 128 queries, 89 (70%) were replied to within 72 h; the median delay was 1.1 day. The 39 unanswered queries were sent to backup specialists for reply and 36 of them (92%) were replied to within 72 h. In the remaining three cases, a second-line (backup) specialist was required. The referrals were handled by 54 volunteer specialists from a panel of over 70. Two system operators, located 10 time zones apart, managed the system. The median time from receipt of a new referral to its allocation to a specialist was 0.2 days (interquartile range, IQR, 0.1-0.8). The median interval between receipt of a new referral and first reply was 2.6 days (IQR 0.8-5.9). Automatic message handling solves many of the problems of manual email telemedicine systems and represents a potentially scalable way of doing low-cost telemedicine in the developing world.