[show abstract][hide abstract] ABSTRACT: Venous thromboembolism (VTE) is a complex disorder influenced by numerous risk factors, and occurs frequently in at-risk hospitalized patients. Because appropriate prevention with thromboprophylaxis is underused, we wanted to create an electronic tool to provide a simple risk assessment and suggest appropriate prophylaxis.
To develop the risk matrix, iterative rating of odds ratios was performed for 60 predisposing VTE risk factors, using analytical methods that account for multiple risk factors in a single patient and their non-independence. For exposing risk factors, a single score was assigned to each set of factors, both medical (25 items) and surgical conditions (144 items). A CART regression model was used to integrate the risk scales into a 4-level measure of overall risk. The validity of the level of risk and the appropriateness of 11 different prophylactic approaches was assessed using the RAND/UCLA appropriateness method and validated by expert opinion ratings (n=1998) on sample case scenarios (n=108).
Correlation between the level of risk calculated by the risk matrix and that offered by expert opinion for individual surgical and medical clinical cases was high (65% and 70%, respectively). The matrix over-estimated the level of risk, compared with that offered by expert opinion, in 28% and 20% of surgical and medical cases, respectively, but the appropriate prophylaxis suggested was no different. Between-expert agreement on the appropriateness of the prophylaxis recommendations was high (90-94% of indications).
This computer-based electronic tool for individualized assessment of venous thromboembolic risk successfully identified both the perceived risk of thrombosis and the appropriate prophylactic approach for medical and surgical patients.
[show abstract][hide abstract] ABSTRACT: Most patients with colorectal liver metastases present to general surgeons and oncologists without a specialist interest in their management. Since treatment strategy is frequently dependent on the response to earlier treatments, our aim was to create a therapeutic decision model identifying appropriate procedure sequences.
We used the RAND Corporation/University of California, Los Angeles Appropriateness Method (RAM) assessing strategies of resection, local ablation and chemotherapy. After a comprehensive literature review, an expert panel rated appropriateness of each treatment option for a total of 1,872 ratings decisions in 252 cases. A decision model was constructed, consensus measured and results validated using 48 virtual cases, and 34 real cases with known outcomes.
Consensus was achieved with overall agreement rates of 93.4 to 99.1%. Absolute resection contraindications included unresectable extrahepatic disease, more than 70% liver involvement, liver failure, and being surgically unfit. Factors not influencing treatment strategy were age, primary tumor stage, timing of metastases detection, past blood transfusion, liver resection type, pre-resection carcinoembryonic antigen (CEA), and previous hepatectomy. Immediate resection was appropriate with adequate radiologically-defined resection margins and no portal adenopathy; other factors included presence of < or = 4 or > 4 metastases and unilobar or bilobar involvement. Resection was appropriate postchemotherapy, independent of tumor response in the case of < or = 4 metastases and unilobar liver involvement. Resection was appropriate only for > 4 metastases or bilobar liver involvement, after tumor shrinkage with chemotherapy. When possible, resection was preferred to local ablation.
The results were incorporated into a decision matrix, creating a computer program (OncoSurge). This model identifies individual patient resectability, recommending optimal treatment strategies. It may also be used for medical education.
Journal of Clinical Oncology 10/2005; 23(28):7125-34. · 18.04 Impact Factor
[show abstract][hide abstract] ABSTRACT: This study deals with pharmacotherapeutical issues in pediatrics. The overall impression is that large lacunae exist in research on the pharmacological treatment of children. Most drugs are not studied in a pediatrics population before market introduction, while there are several important differences in drug use and effects between adults and children. Examples -include: - Medication efficacy and safety has usually been tested on adults, but effects are unknown with children as subjects. Pediatric clinical trials are subject to many restrictions (ethics, practical guidelines) - Differences in distribution and elimination of drugs between adults and children, and lack of knowledge about pharmacokinetics and -dynamics - Differences in dose, frequency and route of administration - Differences in compliance and non-compliance - Differences in (tracking of) side effects and adverse reactions due to medications. The Dutch Health Care Insurance Board (abbreviated CVZ for its Dutch name) recognizes the need for research on medications in children. It has issued a study, to be conducted by RAND Europe, to prioritize medications for clinical research in children. The need for researching the use of medication by children has several aspects and involves the expertise of different medical professionals. This project focuses on the following questions: - To what extent do medical professionals face and recognize problems concerning the use of medication by children? - Which concerns exist among these professionals regarding the use of medication by children? - How can these concerns be translated into priorities for research? - Which Organizational structure is needed to give direction to future research? The literature review serves as an inventory to areas of discussion and controversy in the main disease fields of pediatrics.
[show abstract][hide abstract] ABSTRACT: Drug use is an increasing problem in Portugal. In response, following the advice of a select committee, the Portuguese government has recently issued a number of laws implementing a strong harm-reductionistic orientation. The flagship of these laws is the decriminalization of the use and possession for use of drugs. Use and possession for use are now only administrative offenses; no distinction is made between different types of drugs (hard vs. soft drugs) or whether consumption is private or in public. Although most people favor decriminalization in principle, doubts have been expressed about the way the law will be implemented because the law only sets a framework for those communities that wish to undertake such activities--it is an enabling law. This has led to a considerable lack of clarity and increases the risk of dissimilarity of implementation in different parts of the country. The future will show the effects.
The Annals of the American Academy of Political and Social Science 01/2002; 582(1):49-63. · 1.01 Impact Factor
[show abstract][hide abstract] ABSTRACT: EUROPE Institut universitaire de médecine sociale et préventive PREFACE RAND Europe was asked by the Swiss Insurance Association (SIA) to study what treatment strategies are appropriate in dealing with whiplash associated disorders (WAD), with a specific focus on prevention of long-term disability. The main objectives of the study are: 1. Identification of factors related to the event that triggered whiplash as well as to the person that suffers from a whiplash which are conducive to chronic WAD. 2. Determination of what treatments are considered appropriate in specific cases as defined by the conjunction of the identified factors. These objectives are achieved by the conduct of three linked tasks: 1. A statistical analysis of whiplash insurance cases. 2. A review of the existing literature on whiplash (focusing on prognosis and treatment). 3. An expert panel to gain an insight in clinical expertise on WAD. The present document contains the results of the literature review on WAD. It focuses on prognostic factors for WAD and on the appropriateness of different treatment strategies. In addition, it briefly discusses diagnostic methods and epidemiological information on the prevalence of WAD. The basis for this literature review is a literature review done by the Quebec Task Force (QTF) which includes articles on WAD published between January 1980 and September 1993. The present literature review summarizes the relevant parts of the QTF-review, and adds articles that have been published since then (i.e. articles published between October 1993 and March 2001). The literature review mainly serves as an input to the expert panel, but can also be read as a separate document. It needs to be stressed that this review is not a systematic review including only research of the highest scientific quality. Since research of the highest quality is not available in all areas relevant to our research, we also included articles that contain relevant information, but are of lesser quality. We therefore took a somewhat pragmatic approach to the literature review.