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The interaction of CO with an attapulgite-supported, KCl modified CuCl2 catalyst has previously been examined using a combination of XANES, EXAFS and DFT calculations. Exposing the catalyst to CO at elevated temperatures leads to the formation of CO2 as the only identifiable product. However, phosgene production can be induced by a catalyst pre-treatment stage, where the supported CuCl2 sample is exposed to a diluted stream of dichlorine; subsequent CO exposure at â¼643 K then leads to phosgene production. This communication describes a series of FTIR based micro-reactor measurements, coupled with characterisation measurements utilising TEM, XRD and XPS to define the nature of the catalyst at different stages of the reaction coordinate. The CuCl2 catalyst is able to support Deacon activity , establishing this work with the possibility of utilising the oxy-chlorination of CO to produce phosgene. Continuous dosing of CO at elevated temperatures over the chlorine pre-dosed CuCl2 catalyst shows diminishing phosgene production as a function of time-on-stream, indicating surface chlorine supply to be rate-limiting under the reaction conditions studied. A pictorial reaction scheme is proposed to account for the surface chemistry observed.
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The interaction of CO with an attapulgite-supported Cu(ii)Cl2 catalyst has been examined in a micro-reactor arrangement. CO exposure to the dried, as-received catalyst at elevated temperatures leads to the formation of CO2 as the only identifiable product. However, phosgene production can be induced by using a catalyst pre-treatment where the supported Cu(ii)Cl2 sample is exposed to a diluted stream of chlorine. Subsequent CO exposure at â¼370 °C then leads to phosgene production. In order to investigate the origins of this atypical set of reaction characteristics, a series of X-ray absorption experiments were performed that were supplemented by DFT calculations. XANES measurements establish that at the elevated temperatures connected with phosgene formation, the catalyst is comprised of Cu+ and a small amount of Cu2+. Moreover, the data show that unique to the chlorine pre-treated sample, CO exposure at elevated temperature results in a short-lived oxidation of the copper. On the basis of calculated CO adsorption energies, DFT calculations indicate that a mixed Cu+/Cu2+ catalyst is required to support CO chemisorption.
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Aspects of the chemistry of selected metal fluorides, which are pertinent to their real or potential use as Lewis acidic, heterogeneous catalysts, are reviewed. Particular attention is paid to ß-aluminum trifluoride, aluminum chlorofluoride and aluminas γ and η, whose surfaces become partially fluorinated or chlorinated, through pre-treatment with halogenating reagents or during a catalytic reaction. In these cases, direct comparisons with nanostructured metal fluorides are possible. In the second part of the review, attention is directed to iron(III) and copper(II) metal chlorides, whose Lewis acidity and potential redox function have had important catalytic implications in large-scale chlorohydrocarbons chemistry. Recent work, which highlights the complexity of reactions that can occur in the presence of supported copper(II) chloride as an oxychlorination catalyst, is featured. Although direct comparisons with nanostructured fluorides are not currently possible, the work could be relevant to possible future catalytic developments in nanostructured materials.
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Cloretos/química , Fluoretos/química , Halogenação , Ácidos de Lewis/química , Metais/química , Nanoestruturas/química , Óxidos/química , Compostos de Alumínio/química , Óxido de Alumínio/química , Catálise , Cobre , Ácido Clorídrico/química , Ferro , OxirreduçãoRESUMO
In previous work by the authors, aspects of the surface chemistry connected with methyl chloride synthesis over an η-alumina catalyst have been examined. This communication considers a role for Group 1 metal salts to modify the catalytic performance of the well characterised η-alumina catalyst. Firstly, based on a previously postulated mechanism for the reaction of methanol on η-alumina, a mechanism for methyl chloride synthesis over the η-alumina catalyst is proposed. Secondly, the validity of the new mechanism is tested by observing how the (i) type and (ii) loading of the Group 1 metal salt may perturb methyl chloride selectivity. The outcomes of these measurements are rationalised with reference to the postulated mechanism. Overall, this study represents an example of how a proposed reaction mechanism has been used to inform and guide a catalyst development strategy for a large-scale industrial process.
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A modern industrial route for the manufacture of methyl methacrylate involves the reaction of methyl propanoate and formaldehyde over a silica-supported Cs catalyst. Although the process has been successfully commercialised, little is known about the surface interactions responsible for the forward chemistry. This work concentrates upon the interaction of methyl propanoate over a representative silica. A combination of infrared spectroscopy, inelastic neutron scattering, DFT calculations, X-ray diffraction and temperature-programmed desorption is used to deduce how the ester interacts with the silica surface.
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We report the charge-changing cross sections (σcc) of 24 p-shell nuclides on both hydrogen and carbon at about 900A MeV, of which 8,9Li, 10-12Be, 10,14,15B, 14,15,17-22N and 16O on hydrogen and 8,9Li on carbon are for the first time. Benefiting from the data set, we found a new and robust relationship between the scaling factor of the Glauber model calculations and the separation energies of the nuclei of interest on both targets. This allows us to deduce proton radii (Rp) for the first time from the cross sections on hydrogen. Nearly identical Rp values are deduced from both target data for the neutron-rich carbon isotopes; however, the Rp from the hydrogen target is systematically smaller in the neutron-rich nitrogen isotopes. This calls for further experimental and theoretical investigations.
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INTRODUCTION: In this phase of the ongoing What Matters Most study series, designed to evaluate concepts that are meaningful to people affected by Alzheimer's disease (AD), we quantified the importance of symptoms, impacts, and outcomes of AD to people at risk for or with AD and care partners of people with AD. METHODS: We administered a web-based survey to individuals at risk for or with AD (Group 1: unimpaired cognition with evidence of AD pathology; Group 2: AD risk factors and subjective cognitive complaints/mild cognitive impairment; Group 3: mild AD) and to care partners of individuals with moderate AD (Group 4) or severe AD (Group 5). Respondents rated the importance of 42 symptoms, impacts, and outcomes on a scale ranging from 1 ("not at all important") to 5 ("extremely important"). RESULTS: Among the 274 respondents (70.4% female; 63.1% white), over half of patient respondents rated all 42 items as "very important" or "extremely important," while care partners rated fewer items as "very important" or "extremely important." Among the three patient groups, the minimum (maximum) mean importance rating for any item was 3.4 (4.6), indicating that all items were at least moderately to very important. Among care partners of people with moderate or severe AD, the minimum (maximum) mean importance rating was 2.1 (4.4), indicating that most items were rated as at least moderately important. Overall, taking medications correctly, not feeling down or depressed, and staying safe had the highest importance ratings among both patients and care partners, regardless of AD phase. CONCLUSION: Concepts of importance to individuals affected by AD go beyond the common understanding of "cognition" or "function" alone, reflecting a desire to maintain independence, overall physical and mental health, emotional well-being, and safety. Preservation of these attributes may be key to understanding whether interventions deliver clinically meaningful outcomes.
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INTRODUCTION: Insight into the relationship between concepts that matter to the people affected by Alzheimer's disease (AD) and the clinical outcome assessments (COAs) commonly used in AD clinical studies is limited. Phases 1 and 2 of the What Matters Most (WMM) study series identified and quantitatively confirmed 42 treatment-related outcomes that are important to people affected by AD. METHODS: We compared WMM concepts rated as "very important" or higher to items included in COAs used commonly in AD studies. RESULTS: Twenty COAs designed to assess signs, symptoms, and impacts across the spectrum of AD were selected for review. Among these 20 COAs, only 5 reflected 12 or more WMM concepts [Integrated Alzheimer's Disease Rating Scale (iADRS), Alzheimer's Disease Cooperative Study-Activities of Daily Living Inventory (ADCS-ADL), Alzheimer's Disease Cooperative Study-Activities of Daily Living Inventory-Mild Cognitive Impairment (ADCS-ADL-MCI), Alzheimer's Disease Composite Scores (ADCOMS), and Clinical Dementia Rating; Clinical Dementia Rating-Sum of Boxes (CDR/CDR-SB)]. Multiple symptoms and impacts of AD identified as important and meaningful in the WMM studies map only indirectly at best to 7 of the 20 most widely used COAs. CONCLUSION: While many frequently used COAs in AD capture some concepts identified as important to AD populations and their care partners, overlap between any single measure and the concepts that matter to people affected by AD is limited. The highest singly matched COA reflects fewer than half (45%) of WMM concepts. Use of multiple COAs expands coverage of meaningful concepts. Future research should explore the content validity of AD COAs planned for AD trials based on further confirmation of the ecological validity of the WMM items. This research should inform development and use of core outcome sets that capture WMM items and selection or development of new companion tools to fully demonstrate clinically meaningful outcomes spanning WMM.
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As part of a program to investigate aspects of surface chemistry relevant to methyl chloride synthesis catalysis, the interaction of methanol with η-alumina doped with either CsCl or KCl in the range 0.01-1.0 mmol g(cat) -1 is investigated by a combination of diffuse reflectance infrared Fourier transform spectroscopy and temperature-programed desorption (TPD). Infrared spectra (IR) recorded at 293 K show that increasing the concentration of the group 1 metal chloride progressively decreases the surface concentration of associatively chemisorbed methanol and changes the environment in which the adsorbed methanol resides. For CsCl concentrations of ≥0.6 mmol g(cat) -1, chemisorbed methoxy species dominate the IR spectrum, while TPD studies show that the amount of methanol adsorbed onto the surface, and subsequently desorbed unchanged, changes relatively little. In the TPD experiments, some of the adsorbed methanol reacts to give dimethyl ether (DME) which then desorbs; for dopant concentrations of 1.0 mmol g(cat) -1, DME formation is suppressed to below the limit of detection. Unexpectedly, the presence of formate species generated at 293 K is also observed spectroscopically, characterized by a νasym(COO) mode which exhibits a hypsochromic shift relative to potassium formate; surface concentrations of formate are higher at higher loadings of group 1 metal chloride. Temperature-programed IR spectroscopy shows that the room-temperature formate species desorbs, decomposes, or migrates on warming to 653 K. Thermal ramping of the methanol-saturated surface also results in formate production but one that exhibits an IR profile in agreement with earlier observations and literature values. Increasing the concentrations of the group 1 metal chloride progressively decreases the presence of the thermally induced formate moiety. The study not only reinforces the concept of group 1 metal chloride additives progressively rendering ineffective those Lewis acid sites present at the η-alumina surface which convey discrete reaction characteristics [e.g., (i) dimerization of methanol to form DME and (ii) an activated methoxy â formate transition] but also suggests the generation of reactive sites not present in the undoped alumina.
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The effect of relatively low concentrations of Br2(g) in the Cl2(g) feedstock for phosgene synthesis catalysis via the reaction of CO(g) and Cl2(g) over activated carbon (Donau Supersorbon K40) is explored. Under the stated reaction conditions and in the absence of a catalyst, BrCl(g) forms from the reaction of Cl2(g) and Br2(g). Phosgene synthesis over the catalyst at 323 K is investigated for Br2(g):Cl2(g) molar flow ratios in the range 0-1.52% (0-15,190 ppm) and shows enhanced rates of phosgene production. Maximum phosgene production is observed at a Br2(g):Cl2(g) molar flow ratio of 1.52% (15,190 ppm), which corresponds to an enhancement in the rate of phosgene production of â¼227% with respect to the phosgene flow rate observed in the absence of an incident bromine co-feed. A reaction model is proposed to account for the experimental observables, where BrCl(g) is highlighted as a significant intermediate. Specifically, enhanced rates of phosgene production are associated with the dissociative adsorption of BrCl(g) that indirectly increases the pool of Cl(ad) available for reaction.
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OBJECTIVES: Pulmonary complications of RA are well described. Although some are benign, interstitial lung disease (ILD) has a poor prognosis. Few RA inception cohorts have reported the natural history of ILD related to RA (RA-ILD). We examine its incidence, outcome and prognostic indicators. METHODS: Extra-articular features and comorbidity have been recorded yearly in a well-established inception cohort of RA with a 20-year follow-up. Standard clinical, laboratory and radiological measures of RA were recorded at baseline and yearly. Details of deaths were provided by a national central register. RESULTS: Out of 1460 patients, 52 developed RA-ILD, half either at baseline or within 3 years of onset. The annualized incidence was 4.1/1000 (95% CI 3.0, 5.4) and the 15-year cumulative incidence 62.9/1000 (95% CI 43.0, 91.7). Incidence of RA-ILD was associated with older age, raised baseline ESR and HAQ. Evidence to implicate any drug effect (e.g. MTX) was lacking. Of these patients, 39 died, attributed to RA-ILD in 28. Median survival following diagnosis of RA-ILD was 3 years. CONCLUSIONS: RA-ILD is an important and early feature of RA. It is related to disease activity and has a poor prognosis. Further studies are required to determine whether screening for pulmonary disease would identify these patients at an earlier stage.
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Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Doenças Pulmonares Intersticiais/etiologia , Idoso , Artrite Reumatoide/tratamento farmacológico , Estudos de Coortes , Inglaterra , Feminino , Seguimentos , Humanos , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Resultado do TratamentoRESUMO
The hydrochlorination of 4,4'-methylenedianiline, NH(2)C(6)H(4)CH(2)C(6)H(4)NH(2) (MDA), in chlorobenzene to produce 4,4'-methylenedianiline dihydrochloride, [H(3)NC(6)H(4)CH(2)C(6)H(4)NH(3)]Cl(2) (MDA x 2 HCl) is an important reaction for the production of isocyanates, which are used to manufacture polyurethanes. This reaction is examined here. MDA is moderately soluble in chlorobenzene, whereas MDA x 2 HCl is effectively insoluble. Controlled addition of anhydrous HCl to MDA in chlorobenzene led to the isolation of a solid whose stoichiometry is MDA x HCl. Crystals obtained from solutions of MDA x HCl in methanol were found by X-ray analysis to consist of the basic hydrochloride salt, [MDAH(2)][Cl](2)[MDA](2)H(2)O, which is stabilised by complex hydrogen-bonding. The starting material MDA has an H-bonded structure in which the molecules are linked in a one-dimensional chain. Hydrogen-bonding is extensive in MDA x 2 HCl which contains ladders of [H(3)NC(6)H(4)CH(2)C(6)H(4)NH(3)](2+) dications stabilised by N-H...Cl linkages. Energy calculations on the crystalline systems allow an identification of the main factors in intermolecular cohesion; these are related to melting temperature and solubility data. Such improvements in understanding of solute-solute interactions are prerequisites for improving the atom economy of this important stage within the polyurethane manufacture process chain. The solid phase IR spectrum of MDA x 2 HCl is diagnostic, principally as a result of a Fermi resonance process.
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BACKGROUND: The What Matters Most (WMM) study was initiated to evaluate symptoms, AD-related impacts, treatment-related needs, preferences, and priorities among individuals with or at risk for Alzheimer's disease (AD) and their care partners. The objective of this qualitative study phase was to identify a comprehensive set of concepts of interest that are meaningful to individuals across the AD continuum. METHODS: Interviews were conducted with 60 clinically referred individuals and care partners across 5 AD stages (n = 12 each): group 1 (non-clinically impaired individuals with AD pathology), group 2 (individuals with mild cognitive impairment and AD pathology), group 3 (individuals with mild AD), group 4 (individuals with moderate AD and their care partners), and group 5 (care partners of individuals with severe AD). Interviews were conducted by experienced interviewers, audio-recorded, and transcribed. Dominant trends were identified in each interview and compared across subsequent interviews to generate themes or patterns in descriptions of AD symptoms, impacts, and desired treatment outcomes. RESULTS: All participants endorsed current issues related to memory; nearly all participants (n = 55; 92%) across the five groups endorsed symptoms related to communication and language. Groups 1-3 reported an impact on mood/emotions (n = 23; 64%) and a decrease in social activities or outgoingness (n = 17; 47%). Current and future concerns reported by the overall sample included memory (n = 48; 80%), dependence (n = 40; 67%), and "other" concerns (n = 33; 55.0%) (e.g., uncertainty about the future, burdening others). The most desired AD treatment outcomes were improvement or restoration of memory (n = 40; 67%) and stopping AD progression (n = 35; 58.3%). Group-level differences were observed in the symptoms, impacts, and desired treatment outcomes among patients and care partners across the AD continuum. CONCLUSIONS: Cognitive functioning issues-particularly in memory and communication-are present even in preclinical and early-stage AD, including among those without a formal AD diagnosis. While the impacts of AD vary across the disease-severity spectrum, improved memory and disease modification were treatment outcomes considered most important to participants across all 5 AD stages. Neuropsychological assessments traditionally used in AD clinical trials may not evaluate the often-subtle concepts that are important to patients and care partners. Results from this study will inform the second phase of the WMM project-a quantitative study to elicit the relative importance of these concepts of interest to people at risk for and living with AD and their care partners.
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Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/terapia , Cuidadores , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/terapia , Humanos , Memória , Testes NeuropsicológicosRESUMO
The effect of modifying an η-alumina methyl chloride synthesis catalyst by doping with CsCl and KCl over the concentration range of 0.1-1.0 mmol g(cat) -1 is investigated by a combination of pyridine chemisorption coupled with infrared spectroscopy and mass-selective temperature-programmed desorption measurements. The loading of group 1 metal chloride is equivalent to a titrant that enables selective neutralization of Lewis acid sites present at the surface of the reference η-alumina catalyst. Specifically, a loading of 0.1 mmol g(cat) -1 is sufficient to neutralize the strong Lewis acid sites; a loading of 0.6 mmol g(cat) -1 is sufficient to neutralize the strong and medium-strong Lewis acid sites; a loading of 1.0 mmol g(cat) -1 neutralizes all of the strong and medium-strong Lewis acid sites and partially neutralizes the medium-weak Lewis acid site. These deductions connect with a catalyst design program to develop a methyl chloride synthesis catalyst that exhibits minimal formation of the byproduct dimethyl ether.
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Address arthritis-associated pain as a disease entity, not as a sensory entity. Attempt to classify chronic pain as nociceptive pain, neuropathic pain, fibromyalgia-type pain, or psychogenic pain (very uncommon); specific treatment approaches are required for these different types of pain. Overcome your negative bias against fibromyalgia and review recent discoveries that have led to classification of fibromyalgia as a biologically-based neurosensory disorder. Use the simple and convenient ways that are available to measure pain and its concomitants (fatigue, poor sleep, depression, anxiety, and impaired physical functioning) both at initial evaluation and in follow-up visits as a guide to therapy. Do not fear use of opioids; just be careful with this class of drug.
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Artrite/complicações , Medição da Dor , Dor/tratamento farmacológico , Dor/etiologia , Analgésicos/uso terapêutico , Artrite/tratamento farmacológico , Fibromialgia/complicações , Fibromialgia/diagnóstico , Fibromialgia/tratamento farmacológico , HumanosRESUMO
The surface acidity of an activated eta-alumina catalyst has been investigated by examining the interaction of pyridine with the catalyst by a combination of gravimetric and volumetric adsorption isotherms, infrared spectroscopy (diffuse reflectance and transmission), inelastic neutron scattering spectroscopy, temperature-programmed desorption spectroscopy, and gravimetric desorption experiments. From previous work, this surface was considered to contain three types of Lewis acid sites of increasing acidity: weak, medium, and strong. However, this multitechnique approach reveals the presence of an additional type of Lewis acid site. Although the traditional pyridine ring modes about 1580 cm(-1) are consistent with previous studies, temperature-programmed infrared spectroscopy of the surface hydroxyl groups and mass-selective temperature-programmed desorption experiments establish that the medium-strength Lewis acid category can be subdivided into two components. In this way, the surface structure of the activated catalyst is redefined as comprising (i) weak, (ii) medium-weak, (iii) medium-strong and (iv) strong Lewis acid sites. The (O-H) stretching mode of surface hydroxyl groups provides information on the local structure of the distinct sites, and schematic descriptions for these sites are proposed.
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Fibromialgia/história , História do Século XX , História do Século XXI , Humanos , Dor , Reumatologia/história , SíndromeRESUMO
OBJECTIVE: To develop a fibromyalgia (FM) survey questionnaire for epidemiologic and clinical studies using a modification of the 2010 American College of Rheumatology Preliminary Diagnostic Criteria for Fibromyalgia (ACR 2010). We also created a new FM symptom scale to further characterize FM severity. METHODS: The ACR 2010 consists of 2 scales, the Widespread Pain Index (WPI) and the Symptom Severity (SS) scale. We modified these ACR 2010 criteria by eliminating the physician's estimate of the extent of somatic symptoms and substituting the sum of 3 specific self-reported symptoms. We also created a 0-31 FM Symptom scale (FS) by adding the WPI to the modified SS scale. We administered the questionnaire to 729 patients previously diagnosed with FM, 845 with osteoarthritis (OA) or with other noninflammatory rheumatic conditions, 439 with systemic lupus erythematosus (SLE), and 5210 with rheumatoid arthritis (RA). RESULTS: The modified ACR 2010 criteria were satisfied by 60% with a prior diagnosis of FM, 21.1% with RA, 16.8% with OA, and 36.7% with SLE. The criteria properly identified diagnostic groups based on FM severity variables. An FS score ≥ 13 best separated criteria+ and criteria- patients, classifying 93.0% correctly, with a sensitivity of 96.6% and a specificity of 91.8% in the study population. CONCLUSION: A modification to the ACR 2010 criteria will allow their use in epidemiologic and clinical studies without the requirement for an examiner. The criteria are simple to use and administer, but they are not to be used for self-diagnosis. The FS may have wide utility beyond the bounds of FM, including substitution for widespread pain in epidemiological studies.
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Avaliação da Deficiência , Fibromialgia/diagnóstico , Fibromialgia/epidemiologia , Inquéritos Epidemiológicos/tendências , Índice de Gravidade de Doença , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/fisiopatologia , Transtornos Cognitivos/epidemiologia , Comorbidade , Diagnóstico Diferencial , Fadiga/epidemiologia , Feminino , Fibromialgia/fisiopatologia , Humanos , Incidência , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico , Osteoartrite/epidemiologia , Osteoartrite/fisiopatologia , Sensibilidade e Especificidade , Transtornos do Sono-Vigília/epidemiologiaRESUMO
OBJECTIVE: To develop simple, practical criteria for clinical diagnosis of fibromyalgia that are suitable for use in primary and specialty care and that do not require a tender point examination, and to provide a severity scale for characteristic fibromyalgia symptoms. METHODS: We performed a multicenter study of 829 previously diagnosed fibromyalgia patients and controls using physician physical and interview examinations, including a widespread pain index (WPI), a measure of the number of painful body regions. Random forest and recursive partitioning analyses were used to guide the development of a case definition of fibromyalgia, to develop criteria, and to construct a symptom severity (SS) scale. RESULTS: Approximately 25% of fibromyalgia patients did not satisfy the American College of Rheumatology (ACR) 1990 classification criteria at the time of the study. The most important diagnostic variables were WPI and categorical scales for cognitive symptoms, unrefreshed sleep, fatigue, and number of somatic symptoms. The categorical scales were summed to create an SS scale. We combined the SS scale and the WPI to recommend a new case definition of fibromyalgia: (WPI > or =7 AND SS > or =5) OR (WPI 3-6 AND SS > or =9). CONCLUSION: This simple clinical case definition of fibromyalgia correctly classifies 88.1% of cases classified by the ACR classification criteria, and does not require a physical or tender point examination. The SS scale enables assessment of fibromyalgia symptom severity in persons with current or previous fibromyalgia, and in those to whom the criteria have not been applied. It will be especially useful in the longitudinal evaluation of patients with marked symptom variability.