[Vibration as a risk of mastitis during milking]. / Vibration als Mastitis-Risiko beim Melken.

INTRODUCTION: Mastitis is one of the most important factor diseases in dairy cattle worldwide. Milking technique represents one of the factors involved in the development of mastitis. The purpose of this study was to investigate the influence of vibrations during milking on the rate of clinical and subclinical mastitis. For this purpose, milking measurements, tank milk analyses and survey forms (general farm data, assessment of milking work and milking hygiene, teat condition, feeding, farm problems, animal behavior) were assessed in 8 Swiss dairy farms. The results show a correlation between present vibrations at the output of the milk meter and increasing bulk milk somatic cell count. Further, a tendency was shown for vibrations at the input of the milk meter to influence bulk milk somatic cell count. Also, a tendency regarding vibrations at the outlet of the milk meter and acute phase protein milk amyloid A was evident. In conclusion, the results suggest that vibration during milking might have a negative effect on udder health. However, further research with a larger number of dairies is needed to make a more generally valid statement.

INTRODUCTION: La mammite est l'une des maladies les plus importantes chez les vaches laitières dans le monde entier. La technique de traite représente l'un des facteurs impliqués dans le développement de la mammite. L'objectif de cette étude était d'étudier l'influence des vibrations pendant la traite sur le taux de mammites cliniques et subcliniques. Pour ce faire, des mesures de traite, des analyses de lait de tank et des formulaires d'enquête (données générales de l'exploitation, évaluation du travail de traite et de l'hygiène de la traite, état des trayons, alimentation, problèmes de l'exploitation, comportement des animaux) ont été évalués dans 8 exploitations laitières suisses. Les résultats montrent une corrélation entre les vibrations présentes à la sortie du compteur à lait et l'augmentation du nombre de cellules somatiques du lait en vrac. En outre, les vibrations à l'entrée du compteur à lait ont tendance à influencer le nombre de cellules somatiques du lait en vrac. De même, une tendance concernant les vibrations à la sortie du compteur à lait et la protéine amyloïde A du lait de phase aiguë a été mise en évidence. En conclusion, les résultats suggèrent que les vibrations pendant la traite pourraient avoir un effet négatif sur la santé de la mamelle. Cependant, des recherches supplémentaires avec un plus grand nombre de laiteries sont nécessaires pour faire une déclaration plus généralement valable.

The spatial distribution of perseverations in neglect patients during a nonverbal fluency task depends on the integrity of the right putamen.

Deficient inhibitory control leading to perseverative behaviour is often observed in neglect patients. Previous studies investigating the relationship between response inhibition and visual attention have reported contradictory results: some studies found a linear relationship between neglect severity and perseverative behaviour whereas others could not replicate this result. The aim of the present study was to shed further light on the interplay between visual attention and response inhibition in neglect, and to investigate the neural underpinnings of this interplay. We propose the use of the Five-Point Test, a test commonly used to asses nonverbal fluency, as a novel approach in the context of neglect. In the Five-Point Test, participants are required to generate as many different designs as possible, by connecting dots within forty rectangles. We hypothesised that, because of its clear definition of perseverative errors, the Five-Point Test would accurately assess both visual attention as well as perseverative behaviour. We assessed 46 neglect patients with right-hemispheric stroke, and performed voxel-based lesion-symptom mapping (VLSM) to identify neural substrates of perseverative behaviour as well as the spatial distribution of perseverations. Our results showed that the Five-Point Test can reliably measure neglect and perseverative behaviour. We did not find any significant relationship between neglect severity and the frequency of perseverations. However, within the subgroup of neglect patients who displayed perseverative behaviour, the spatial distribution of perseverations significantly depended on the integrity of the right putamen. We discuss the putative role of the putamen as a potential subcortical hub to modulate the complex integration between visual attention and response inhibition processes.

5 × 5 cm² silicon photonic crystal slabs on glass and plastic foil exhibiting broadband absorption and high-intensity near-fields.

Crystalline silicon photonic crystal slabs are widely used in various photonics applications. So far, the commercial success of such structures is still limited owing to the lack of cost-effective fabrication processes enabling large nanopatterned areas (≫ 1 cm(2)). We present a simple method for producing crystalline silicon nanohole arrays of up to 5 × 5 cm(2) size with lattice pitches between 600 and 1000 nm on glass and flexible plastic substrates. Exclusively up-scalable, fast fabrication processes are applied such as nanoimprint-lithography and silicon evaporation. The broadband light trapping efficiency of the arrays is among the best values reported for large-area experimental crystalline silicon nanostructures. Further, measured photonic crystal resonance modes are in good accordance with light scattering simulations predicting strong near-field intensity enhancements greater than 500. Hence, the large-area silicon nanohole arrays might become a promising platform for ultrathin solar cells on lightweight substrates, high-sensitive optical biosensors, and nonlinear optics.

[Help, my low back hurts!]. / Mein Rücken schmerzt so sehr!

Osteoporosis is a disease of older people with preference for the female sex. A bilateral fracture of the sacrum in a premenopausal woman with osteoporosis is very rare. We describe the case of a 34-year-old premenopausal woman suffering a bilateral sacral fracture after lifting a bundle of paper. The reason for these fractures was a primary osteoporosis with the risk factors vitamin D insufficiency, smoking, decreased alimentary calcium intake.

Time-lapsed assessment of microcrack initiation and propagation in murine cortical bone at submicrometer resolution.

The strength of bone tissue is not only determined by its mass, but also by other properties usually referred to as bone quality, such as microarchitecture, distribution of bone cells, or microcracks and damage. It has been hypothesized that the bone ultrastructure affects microcrack initiation and propagation. Due to its high resolution, bone assessment by means of synchrotron radiation (SR)-based computed tomography (CT) allows unprecedented three-dimensional (3D) and non-invasive insights into ultrastructural bone phenotypes, such as the canal network and the osteocyte lacunar system. The aims of this study were to describe the initiation and propagation of microcracks and their relation with these ultrastructural phenotypes. To this end, femora from the two genetically distinct inbred mouse strains C3H/He (C3H) and C57BL/6 (B6) were loaded axially under compression, from 0% strain to failure, with 1% strain steps. Between each step, a high-resolution 3D image (700 nm nominal resolution) was acquired at the mid-diaphysis using SR CT for characterization and quantitative analysis of the intracortical porosity, namely the bone canal network, the osteocyte lacunar system and the emerging microcracks. For C3H mice, the canal, lacunar, and microcrack volume densities accounted typically for 1.91%, 2.11%, and 0.27% of the cortical total volume at 2% apparent strain, respectively. Due to its 3D nature, SR CT allowed to visualize and quantify also the volumetric extent of microcracks. At 2% apparent strain, the average microcrack thickness for both mouse strains was 2.0 microm for example. Microcracks initiated at canal and at bone surfaces, whereas osteocyte lacunae provided guidance to the microcracks. Moreover, we observed that microcracks could appear as linear cracks in one plane, but as diffuse cracks in a perpendicular plane. Finally, SR CT images permitted visualization of uncracked ligament bridging, which is thought to be of importance in bone toughening mechanisms. In conclusion, this study showed the power of SR CT for 3D visualization and quantification of the different ultrastructural phases of the intracortical bone porosity. We particularly postulate the necessity of 3D imaging techniques to unravel microcrack initiation and propagation and their effects on bone mechanics. We believe that this new investigation tool will be very useful to further enhance our understanding of bone failure mechanisms.

Evaluation of Swiss guidelines for the indication for hysterectomy in relation to patient outcome.

BACKGROUND: The application of national guidelines which specify the appropriateness for hysterectomy is believed to lead to improved patient outcomes. However, there was no evidence to support this assumption by outcome data. GOALS: To evaluate adherence to guidelines and the validity of the 1997 Swiss guidelines for the appropriateness of hysterectomy based on changes in patients' functional and psychosocial status. METHOD: Multicentre study of 370 consecutive cases from 18 public hospitals assessing data on appropriateness and changes in patient status following hysterectomy. Data on appropriateness were obtained before the procedure (n = 286). Changes in patient status following hysterectomy were assessed using an adapted and weighted score. Baseline data were collected up to 8 weeks prior to hysterectomy. Outcome data were obtained 16-32 weeks after surgery (n = 237). Patients for whom appropriateness data were available (n = 286) were categorized into three groups: (1) 214 patients (74.82%) with an indication for hysterectomy, (2) 36 patients (12.58%) classified as having an indication with regard to their preference, and (3) 36 patients (12.58%) classified as not being appropriate for surgery according to national guidelines. RESULTS: In 87% the indication for hysterectomy was judged as appropriate according to the guidelines. The status of all three groups of patients after hysterectomy was found to be significantly improved compared to baseline levels. Patients with an appropriate indication tended to profit more from hysterectomy. CONCLUSION: The appropriateness rating found may be interpreted as an example of justified use of medical procedural intervention. There was a positive correlation between appropriateness and outcome. The 1997 guidelines still seem to be valid.

3D micro-scale deformations of wood in bending: synchrotron radiation muCT data analyzed with digital volume correlation.

A micro-scale three-point-bending experiment with a wood specimen was carried out and monitored by synchrotron radiation micro-computed tomography. The full three-dimensional wood structure of the 1.57x3.42x0.75mm(3) specimen was reconstructed at cellular level in different loading states. Furthermore, the full three-dimensional deformation field of the loaded wood specimen was determined by digital volume correlation, applied to the reconstructed data at successive loading states. Results from two selected regions within the wood specimen are presented as continuous displacement and strain fields in both 2D and 3D. The applied combination of synchrotron radiation micro-computed tomography and digital volume correlation for the deformation analysis of wood under bending stress is a novel application in wood material science. The method offers the potential for the simultaneous observation of structural changes and quantified deformations during in situ micro-mechanical experiments. Moreover, the high spatial resolution allows studying the influence of anatomical features on the fracture behaviour of wood. Possible applications of this method range from bio-mechanical observations in fresh plant tissue to fracture mechanics aspects in structural timber.

[Tick-borne encephalitis in the North part of the canton de Vaud]. / Méningo-encéphalite verno-estivate dans le Nord vaudois.

Tick-borne encephalitis (TBE) is described in Switzerland since 1969. More than 200 cases are reported every year to the Federal office of public health (FOPH) and new sites of endemic disease have been documented recently, in particular in the North part of the canton de Vaud. The aim of this article is to review the clinical pictures of 11 patients hospitalised in Yverdon-les-Bains with a diagnosis of TBE between 2003 and August 2007. The occurrence of 5 new cases exposed in the North part of the canton de Vaud over these last 18 months confirms the presence of endemic foci in this area and should prompt the vaccination against the MEVE which is recommended by the FOPH in endemic zones. The sequels of MEVE being observed mainly in the elderly, vaccination should be afforded also to this group of patients.

Interrelation of peri-operative morbidity and ASA class assignment in patients undergoing gynaecological surgery.

OBJECTIVE: The aim of this study was to estimate intra- and post-operative risk using the American Society of Anaesthesiologists (ASA) classification which is an important predictor of an intervention and of the entire operating programme. STUDY DESIGN: In this retrospective study, 4435 consecutive patients undergoing elective and emergency surgery at the Gynaecological Clinic of the University Hospital of Zurich were included. The ASA classification for pre-operative risk assessment was determined by an anaesthesiologist after a thorough physical examination. We observed several pre-, intra- and post-operative parameters, such as age, body-mass-index, duration of anaesthesia, duration of surgery, blood loss, duration of post-operative stay, complicated post-operative course, morbidity and mortality. The investigation of different risk factors was achieved by a multiple linear regression model for log-transformed duration of hospitalisation. RESULTS: Age and obesity were responsible for a higher ASA classification. ASA grade correlates with the duration of anaesthesia and the duration of the surgery itself. There was a significant difference in blood loss between ASA grades I (113+/-195 ml) and III (222+/-470 ml) and between classes II (176+/-432 ml) and III. The duration of post-operative hospitalisation could also be correlated with ASA class. ASA class I=1.7+/-3.0 days, ASA class II=3.6+/-4.3 days, ASA class III=6.8+/-8.2 days, and ASA class IV=6.2+/-3.9 days. The mean post-operative in-hospital stay was 2.5+/-4.0 days without complications, and 8.7+/-6.7 days with post-operative complications. Multiple linear regression model showed that not only the ASA classification contained an important information for the duration of hospitalisation. Parameters such as age, class of diagnosis, post-operative complications, etc. also have an influence on the duration of hospitalisation. CONCLUSION: This study shows that the ASA classification can be used as a good and early available predictor for the planning of an intervention in gynaecological surgery. The ASA classification helps the surgeon to assess the peri-operative risk profile of which important information can be derived for the planning of the operation programme.

Time-lapsed investigation of three-dimensional failure and damage accumulation in trabecular bone using synchrotron light.

Synchrotron radiation micro-computed tomography (SRmicroCT) is a very useful technique when it comes to three-dimensional (3D) imaging of complex internal and external geometries. Being a fully non-destructive technique, SRmicroCT can be combined with other experiments in situ for functional imaging. We are especially interested in the combination of SRmicroCT with mechanical testing in order to gain new insights in the failure mechanism of trabecular bone. This interest is motivated by the immense costs in health care due to patients suffering from osteoporosis, a systemic skeletal disease resulting in decreased bone stability and increased fracture risk. To better investigate the different failure mechanisms on the microlevel, we have developed a novel in situ mechanical compression device, capable of exerting both static and dynamic displacements on experimental samples. The device was calibrated for mechanical testing using solid aluminum and bovine trabecular bone samples. To study different failure mechanisms in trabecular bone, we compared a fatigued and a non-fatigued bovine bone sample with respect to failure initiation and propagation. The fatigued sample failed in a burst-like fashion in contrast to the non-fatigued sample, which exhibited a distinct localized failure band. Moreover, microscopic cracks - microcracks and microfractures - were uncovered in a 3D fashion illustrating the failure process in great detail. The majority of these cracks were connected to a bone surface. The data also showed that the classification of microcracks and -fractures from 2D section can sometimes be ambiguous, which is also true for the distinction of diffuse and distinct microdamage. Detailed investigation of the failure mechanism in these samples illustrated that trabecular bone often fails in delamination, providing a mechanism for energy dissipation while conserving trabecular bone architecture. In the future, this will allow an even better understanding of bone mechanics related to its hierarchical structural organization.

Comparison of microfocus- and synchrotron X-ray tomography for the analysis of osteointegration around Ti6Al4V implants.

Micro-computed tomography (microCT) provides quantitative three-dimensional information of bone around titanium implants similar to classical histology. The study, based on an animal model, containing cuboid-shaped biofunctionalised Ti6Al4V implants with surrounding bone after 4 weeks, is performed using 3 microCT-systems with X-ray tubes, one synchrotron-radiation-based microCT-system (SRmicroCT), and classical histology. Although the spatial resolution of the microCT-systems is comparable, only the results of SRmicroCT agree with results of classical histology. The X-ray tube sources give rise to huge artefacts in the tomograms (interface scattering, beam hardening), which impaired the quantitative analysis of bone up to about 200microm from the implant surface. Due to the non-destructive character of microCT the specimens can be subsequently examined by classical histology without restriction. The quantitative comparison of bone formation uncovers the strong dependence of the newly formed bone from the selected slice. This implies the necessity of 3D analysis. SRmicroCT and classical histology prove that surface modifications of the titanium implant significantly influence the bone formation. Using SRmicroCT, the preparation artefacts due to cutting and polishing are excluded.

Cost-effectiveness studies in ovarian cancer.

Ovarian cancer is the fifth leading cause of cancer-related deaths. The costs associated with this cancer impact both on the affected individual and on the health system. Screening is currently unproven as a strategy for improving outcomes for women with ovarian cancer. Randomized controlled trials, however, are underway, estimating any impact of screening with ultrasound and CA125 on ovarian cancer mortality. Paclitaxel and carboplatin combination, the standard first-line chemotherapy regimen for ovarian cancer, has not been compared with cisplatin and cyclophosphamide regarding the cost-effectiveness and cost-utility, but for paclitaxel and cisplatin, numerous studies have addressed these issues. The estimated incremental costs resulting from these studies fall well within the generally accepted range for new therapies. Although acquisition costs of new chemotherapy drugs exceed those of older drugs, the impact of costly drugs on total costs may be cost saving due to less costs related to supportive and palliative care. The most important costs for the patient, the pain and suffering associated with ovarian cancer and its treatment, are hard to quantify. Nevertheless, patients' quality of life must be considered when making a clinical decision to treat this disease. A review of available cost-effectiveness studies is presented and discussed.

Impact of the reduction of anaesthesia turnover time on operating room efficiency.

BACKGROUND AND OBJECTIVE: We investigated whether an increase in anaesthesia staffing to permit induction of anaesthesia before the previous case had ended ('overlapping') would increase overall efficiency in the operating room. Hitherto, the average duration of operating sessions was too long, thus impeding the timely commencement of physicians' ward duties. METHODS: The investigation was designed as a prospective, non-randomized, interrupted time-series analysis divided into three phases: (a) a baseline of 3.5 months, (b) a 2.5 month intervention phase, in which anaesthesia staffing was increased by one attending physician and one nurse, and (c) a further 2 months under baseline conditions. Data focussed on process management were collected from operating room staff, anaesthesia personnel and surgeons using a structured questionnaire collected daily during the entire study. RESULTS: Turnover time between consecutive operations decreased from 65 to 52 min per operation (95% CI: 9; 17; P = 0.0001). Operating room occupancy increased from 4:28 to 5:27 h day-1 (95% CI: 50; 68; P = 0.005). The surgeons began their work on the ward 35 min (95% CI: 30; 40) later than before the intervention and their overtime increased from 22:36 to 139:50 h. CONCLUSIONS: The time between surgical operations decreased significantly. Increased operating room efficiency owing to overlapping induction of anaesthesia allows more intense scheduling of operations. Thus, physicians and nurses can be released to spend more time with their patients in the ward. Improving the efficiency of the operating room alone is insufficient to improve human resource management at all levels of a surgical clinic.

Necrosis of the tongue and unilateral blindness in temporal arteritis.

While blindness is one of the typical clinical presentations of temporal arteritis, tongue necrosis, on the other hand, is an unusual complication of the disease. An 80 year old male patient presenting a sudden massive swelling of the tongue was admitted to the Hospital of Yverdon. The swelling rapidly progressed to a complete necrosis of the tongue within a few days. The clinical presentation, the dramatic evolution of the necrosis, and sudden unilateral blindness despite prompt treatment confirmed our diagnosis of temporal arteritis. However, all the examinations, including biopsy of the right temporal artery, remained non-specific for the disease. Our diagnosis was based on the unusual clinical presentation of the disease.

Skin protection for photosensitized patients.

BACKGROUND AND OBJECTIVE: The goal of this study was to evaluate various creams for their capability to protect photosensitized skin from visible light. STUDY DESIGN/MATERIALS AND METHODS: Two cover creams and creams containing various combinations of Vaseline with TiO(2), ZnO, and Fe(2)O(3) were used to measure the reduced light transmission and the light absorption spectrum. In vitro and in vivo tests were performed to assess the protection from light by above mentioned compounds. RESULTS: The cover creams and the 50% TiO(2) cream showed similar efficacy in reducing light transmission, while the sunscreen was less efficient by a factor of 5. Cell protection by 25% TiO(2)+25% ZnO, TiO(2), or the cover creams was more efficient than protection by the sunscreen or other compounds. In vivo, the dark cover cream protected the skin by a factor of 3.4 better than the sunscreen. CONCLUSION: The dark cover cream has acceptable properties to protect photosensitized skin.

Photodynamic therapy of locoregional breast cancer recurrences using a chlorin-type photosensitizer.

Chest wall recurrences are a frequent problem in patients treated by mastectomy for breast cancer. Surgery and ionizing radiation are established treatment modalities in these cases. Photodynamic therapy (PDT) provides an alternative treatment modality using a photosensitizer and laser light to induce selective tumor necrosis. PDT was performed as compassionate use in 7 patients aged 57.6 years (+/-12.6 SD). A total of 89 metastatic skin nodes were treated in 11 PDT sessions. As photosensitizer meta-tetra(hydroxyphenyl)chlorin (m-THPC) was applied intravenously. Patients (n = 3) photosensitized with a drug dose of 0.10 mg/kg bodyweight were irradiated 48 hr after drug application at a lightdose of 5 J/cm(2). Patients (n = 4) were illuminated by an optical dose of 10 J/cm(2) 96 hr after photosensitization with 0.15 mg/kg. Laser light at a wavelength of 652 nm was generated by a diode laser and applied by a front lens light diffuser using a fluence rate of 20--25 mW/cm(2). PDT using m-THPC resulted in complete response in all patients. Response to treatment did not differ when using the 2 different drugdose protocols. Healing time depended mainly on the size of the illumination field but not on the lightdose. Pain score usually raised 1 day after PDT and lasted at higher levels for about 10 days. Healing time usually ranged between 8--10 weeks. Photodynamic technique offers a minimal-invasive, outpatient treatment modality for recurrent breast cancer on the chest wall with few side effects, high patient's satisfaction and with possible repetitive application.

Photodynamic therapy of vulvar intraepithelial neoplasia III using topically applied 5-aminolevulinic acid.

OBJECTIVES: The aim of this study was twofold: first, to determine the feasibility of photodynamic therapy (PDT) of vulvar intraepithelial neoplasia III (VIN III) using topically applied 5-aminolevulinic acid (ALA) for photosensitization, and second, to compare PDT results with those of laser evaporation and local excision. METHODS: Fifteen patients with VIN III had 10 g of 10% ALA gel applied to the entire vulva. Two to three hours after drug application the vulva was irradiated with 120 J/cm(2) laser light at a wavelength of 635 nm. The procedure was performed without anesthesia in most patients. Thirty patients with VIN III treated by laser evaporation and 27 patients treated by surgical excision served as controls. RESULTS: Eight weeks following PDT, 11 of 15 patients were free of VIN III as determined by biopsy. Excellent tissue preservation was achieved and no ulcers or scarring occurred. Three recurrences were seen during follow-up, at 5, 6, and 7 months after PDT. Twelve months after treatment, analysis of disease-free survival revealed no statistically significant difference between patients treated with PDT and patients treated with conventional treatment modalities (P = 0.67) but the power of this analysis is low. In multivariate analysis, multifocal disease was the sole variable associated with a reduced disease-free survival. CONCLUSION: While PDT of VIN III seems to show efficacy similar to that of conventional treatment modalities it offers unique advantages: healing time is short, preservation of normal vulvar appearance is excellent, and PDT may be performed without anesthesia. Hence, PDT of VIN III deserves further investigation.

PEG-m-THPC-mediated photodynamic effects on normal rat tissues.

Photodynamic therapy (PDT) of malignancies uses light to activate a photosensitizer preferentially accumulated in cancer cells. The first pegylated photosensitizer, tetrakis-(m-methoxypolyethylene glycol) derivative of 7,8-dihydro-5,10,15,20-tetrakis(3-hydroxyphenyl)-21-23-[H]-porphyrin (PEG-m-THPC), was evaluated in non-tumor-bearing rats. The aim of this study was to assess the photodynamic threshold for damage and its sequelae in normal rat tissue. Thirty-five Fischer rats were sensitized with 3, 9 or 30 mg/kg body weight PEG-m-THPC. Colon, vagina and perineum were irradiated with laser light of 652 nm wavelength and an optical dose of 50, 150 or 450 J/cm fiber length. Temperature in the pelvis was measured during PDT. Three days following PDT the effect on skin, vagina, colon, striated muscle, connective tissue, nerves and blood vessels was assessed by histology. The healing of the above-mentioned tissues was assessed on two rats 3 and 8 weeks after PDT using 9 mg/kg PEG-m-THPC activated with 450 J/cm laser light. No dark toxicity was observed. PDT using 30 mg/kg PEG-m-THPC induced severe necrosis irrespective of the optical dose. Body weight of 9 or 3 mg/kg activated with less than 450 J/cm induced moderate or no damage. No substantial increase in body temperature was seen during PDT. Tissues with severe PDT-induced damage seem to have a good tendency to regenerate. We conclude that within the dose required for tumor treatment PEG-m-THPC is a safe photosensitizer with promising properties. PDT of the colon mucosa below 9 mg/kg PEG-m-THPC and 150 J/cm seems to be safe. All other tissues can be exposed to 9 mg/kg PEG-m-THPC activated with less than 450 J/cm laser light with little side effects.

Appropriateness and necessity research on the Internet: using a "second opinion system".

Appropriateness and necessity research of various procedures in medicine may be the most complex field of innovation in healthcare and technology assessment. Nevertheless, the appropriateness of the indication of any medical intervention is probably more important than the outcome since even ideal quality components of structures, processes and outcomes become irrelevant without a proper indication. The first part of our appropriateness initiative in interventional cardiology and gynecology was to formulate guidelines. To define the appropriateness for coronary angiography, coronary revascularization and hysterectomy, literature-based consensus methods were used. The second part was to disseminate the guidelines in a user-friendly manner via the Internet. Therefore, we relied on a system-driven query facility for propositional (experts) rules. The next part of the appropriateness initiative may be a user-friendly Internet-based data collection system to validate the national accepted guidelines. Most important may be that only data that is needed can be collected using a refined database technology. The described Second Opinion System can be found under: http:sos.inf.ethz.ch. Research on indications with data on clinical outcome may open new opportunities to validate indication guidelines using Internet/database technology for data analysis and browsing of decision graphs concerning clinical decision-making. This new technology facilitates the evaluation of appropriateness and necessity criteria in combination with clinical outcomes.