Testing the mean of an asymmetric population: Johnson's modified t test revisited

Probability

Fault interpretation in seismic reflection data: an experiment analyzing the impact of conceptual model anchoring and vertical exaggeration

[EN]This paper presents an analysis on the limitations and advantages that some types of seismic data display present on the interpretation of the dataset

Comparison of clinical burden between patients with erosive hand osteoarthritis and inflammatory arthritis in symptomatic community-dwelling adults: the Keele clinical assessment studies.

OBJECTIVE: To investigate in the general population the clinical impact of erosive OA in interphalangeal joints (IPJs) compared with symptomatic radiographic hand OA and inflammatory arthritis. METHODS: Standardized assessments with hand radiographs were performed in participants of two population-based cohorts in North Staffordshire with hand symptoms lasting ≥1 day in the past month. Erosive OA was defined as the presence of an eroded or remodelled phase in ≥1 IPJ using the Verbruggen-Veys method. Radiographic hand OA was defined as the presence of ≥1 IPJ/first carpometacarpal joint with a Kellgren-Lawrence score of ≥2. Diagnoses of inflammatory arthritis were based on medical records. Hand pain and disability were assessed with the Australian/Canadian Hand Osteoarthritis Index (AUSCAN). Linear regression analyses were used to compare clinical determinants between groups and calculate mean differences with 95% CIs, adjusted for age and sex. RESULTS: Of 1076 participants with hand symptoms [60% women, mean age 64.8 years (s.d. 8.3 years)]; 80 persons (7.4%) had erosive OA. The population prevalence of erosive OA in ≥1 IPJ was 2.4% (95% CI 1.8, 3.0). Persons with erosive OA reported more pain and disability than persons with symptomatic radiographic hand OA [adjusted mean difference 1.3 (95% CI 0.3, 2.3) and 2.3 (95% CI 0.4, 4.2), respectively]. Individuals with inflammatory arthritis (n = 44) reported more pain and disability than those with erosive OA [adjusted mean difference 1.7 (95% CI 0.05, 3.4) and 6.3 (95% CI 2.8, 9.9), respectively]. CONCLUSION: While erosive OA has a greater impact than symptomatic radiographic hand OA in the general population, it is not as severe in terms of hand pain and disability as inflammatory RA

Erosive osteoarthritis: a more severe form of radiographic hand osteoarthritis rather than a distinct entity?

OBJECTIVES: To determine whether erosive osteoarthritis shares the same pattern of joint involvement and risk profile as increasing grades of non-erosive hand osteoarthritis. METHODS: Participants were from two population-based cohorts, aged ≥50 years, reporting hand symptoms in the previous month. Interphalangeal joints were assessed for erosive osteoarthritis (Verbruggen-Veys erosive or remodelled phase) and radiographic osteoarthritis (sliding cut-offs of K&L≥2, K&L≥3 and K&L=4). At the joint level, similarities in the frequency and pattern of erosive and non-erosive osteoarthritis were assessed by Spearman's rank correlation coefficients and generalised estimating equations. At the person level, individuals with erosive osteoarthritis were compared to those with non-erosive osteoarthritis using logistic regression, adjusted for age and gender (aOR), for the following exposures: family history, previous injury, overuse and metabolic factors (BMI, dyslipidaemia, hypertension, diabetes). RESULTS: In 1076 symptomatic participants the ranked frequency of involvement for erosive joints was comparable to joints with K&L≥3 and K&L=4 (r>0.95). Patterns of joint involvement in erosive osteoarthritis were strongest for symmetry (aOR=6.5; 95% CI 3.0 to 14.1), followed by row (2.0; 0.8 to 5.0) and ray (0.3; 0.0 to 2.5), which was similar to joints with K&L≥3 and K&L=4. Individuals with erosive osteoarthritis (n=80) had an increased risk of metabolic syndrome (2.7; 1.0 to 7.1), notably dyslipidaemia (4.7; 2.1 to 10.6) compared with non-erosive osteoarthritis classed K&L≥3 (n=193). CONCLUSIONS: The similar frequency of radiographic joint involvement and patterning in erosive osteoarthritis and more severe non-erosive osteoarthritis is consistent with prevalent erosive osteoarthritis being a severe form of hand osteoarthritis rather than a distinct entity. Metabolic exposures, dyslipidaemia in particular, may be implicated in erosive osteoarthritis

Osteoarthritis research priorities: a report from a EULAR ad hoc expert committee

Osteoarthritis (OA) currently affects over 40 million Europeans, with its associated personal suffering and significant economic burden for health systems set to dramatically escalate in a rapidly ageing Europe. Given the very limited effective therapeutic options for OA, the European League Against Rheumatism (EULAR) created an ad hoc committee of OA researchers, clinicians and patients to consider a research agenda focussed on the areas of epidemiology, pathogenesis, imaging and biomarkers, and therapies. The committee deliberated and listed research needs in these areas and also established some cross-area priority themes: predictors of OA progression, especially where this might enable stratified interventions; understanding mechanisms of OA pain; improved understanding of tissue communication in a process where multiple tissue pathologies are common; developing concepts of, and consequently interventions for, early OA where both pain and structural processes may be more effectively targeted than in typical clinical presentations; and the need for new treatment strategies, with examples discussed on pathology-targeted therapies and optimal combinations of therapies. This research agenda should provide useful guidance for all researchers in this field and hopefully lead to improved OA care

EULAR recommendations for the use of imaging in the clinical management of peripheral joint osteoarthritis

The increased information provided by modern imaging has led to its more extensive use. Our aim was to develop evidence-based recommendations for the use of imaging in the clinical management of the most common arthropathy, osteoarthritis (OA). A task force (including rheumatologists, radiologists, methodologists, primary care doctors and patients) from nine countries defined 10 questions on the role of imaging in OA to support a systematic literature review (SLR). Joints of interest were the knee, hip, hand and foot; imaging modalities included conventional radiography (CR), MRI, ultrasonography, CT and nuclear medicine. PubMed and EMBASE were searched. The evidence was presented to the task force who subsequently developed the recommendations. The strength of agreement for each recommendation was assessed. 17 011 references were identified from which 390 studies were included in the SLR. Seven recommendations were produced, covering the lack of need for diagnostic imaging in patients with typical symptoms; the role of imaging in differential diagnosis; the lack of benefit in monitoring when no therapeutic modification is related, though consideration is required when unexpected clinical deterioration occurs; CR as the first-choice imaging modality; consideration of how to correctly acquire images and the role of imaging in guiding local injections. Recommendations for future research were also developed based on gaps in evidence, such as the use of imaging in identifying therapeutic targets, and demonstrating the added value of imaging. These evidence-based recommendations and related research agenda provide the basis for sensible use of imaging in routine clinical assessment of people with OA

EULAR recommendations for the use of imaging in the clinical management of peripheral joint osteoarthritis

The increased information provided by modern imaging has led to its more extensive use. Our aim was to develop evidence-based recommendations for the use of imaging in the clinical management of the most common arthropathy, osteoarthritis (OA). A task force (including rheumatologists, radiologists, methodologists, primary care doctors and patients) from nine countries defined 10 questions on the role of imaging in OA to support a systematic literature review (SLR). Joints of interest were the knee, hip, hand and foot; imaging modalities included conventional radiography (CR), MRI, ultrasonography, CT and nuclear medicine. PubMed and EMBASE were searched. The evidence was presented to the task force who subsequently developed the recommendations. The strength of agreement for each recommendation was assessed. 17â 011 references were identified from which 390 studies were included in the SLR. Seven recommendations were produced, covering the lack of need for diagnostic imaging in patients with typical symptoms; the role of imaging in differential diagnosis; the lack of benefit in monitoring when no therapeutic modification is related, though consideration is required when unexpected clinical deterioration occurs; CR as the first-choice imaging modality; consideration of how to correctly acquire images and the role of imaging in guiding local injections. Recommendations for future research were also developed based on gaps in evidence, such as the use of imaging in identifying therapeutic targets, and demonstrating the added value of imaging. These evidence-based recommendations and related research agenda provide the basis for sensible use of imaging in routine clinical assessment of people with OA

Semences et séquences génétiques en open source ? Expériences récentes et stratégies futures

Le concept d'open source appliqué aux semences végétales a un avenir prometteur. Ce concept inverse la logique du système de propriété intellectuelle pour une ressource renouvelable que l'on rend disponible en la sortant du domaine exclusif de la propriété intellectuelle. Aujourd'hui, les instruments juridiques font encore défaut pour établir un cadre légal complet. Toutefois, le concept d'open source, que l'on pourrait traduire ici par licence libre et ouverte, engendre au fil du temps une masse critique d'utilisateurs et de soutiens qui entraîne une légitimité sociale grandissante. À terme, cette légitimité pourrait renforcer le pouvoir juridique. L'extension future à d'autres matériels dans différents contextes doit être réfléchie en s'appuyant sur les expériences actuelles de semences sous licences libres et ouvertes conduites aux États-Unis, en Europe et en Afrique