Content Analysis of General Practitioner Requested Lumbar Spine X-ray Reports

Aims and Background X-rays of patients with low back pain rarely show serious pathology but frequently reveal incidental age-related changes and always expose people to radiation. Patients who have X-rays are more satisfied but report worse pain and disability. Psychological factors such as illness beliefs,catastrophizing and fear avoidance have been shown to be predictors of chronicity/disability. Authorities suggest that the way X-ray information is transmitted and interpreted by patients may influence outcome, therefore this study was designed to determine the words used by radiologists to describe lumbar spine Xrays. Methods: 120 consecutive X-ray reports for patients referred by primary care physicians were anonymised. A formal summative content analysis was undertaken. The coded words were grouped into categories according to their perceived meaning, and the process was refined until there were only three mutually exclusive categories. Results: Half the sample was aged 60 years or younger. Three categories were identified: anatomical, pathological and descriptive. In the pathological category, 33% of words described normal appearances, 47% described age-related changes and 20% described other features. In only 2% of cases were pathological words used to describe conditions as being "normal for age". Overall, 89 (74%) of the 120 reports contained at least one phrase containing words indicating the presence of degenerative changes. Conclusions: Almost three-quarters of lumbar spine X-ray reports use pathological words such as 'degenerative changes' to describe age-related changes but rarely describe them as being "normal for age"

Pulsar Spin--Velocity Alignment: Further Results and Discussion

The reported alignment between the projected spin-axes and proper motion directions of pulsars is revisited in the light of new data from Jodrell Bank and Effelsberg. The present investigation uses 54 pulsars, the largest to date sample of pulsars with proper-motion and absolute polarisation, to study this effect. Our study has found strong evidence for pulsar spin-velocity alignment, excluding that those two vectors are completely uncorrelated, with >99% confidence. Although we cannot exclude the possibility of orthogonal spin-velocity configurations, comparison of the data with simulations shows that the scenario of aligned vectors is more likely than that of the orthogonal case. Moreover, we have determined the spread of velocities that a spin-aligned and spin-orthogonal distribution of kicks must have to produce the observed distribution of spin-velocity angle offsets. If the observed distribution of spin-velocity offset angles is the result of spin-aligned kicks, then we find that the distribution of kick-velocity directions must be broad with {\sigma}_v~30\degree if the orthogonal-kick scenario is assumed, then the velocity distribution is much narrower with {\sigma}_v<10\degree. Finally, in contrast to previous studies, we have performed robustness tests on our data, in order to determine whether our conclusions are the result of a statistical and/or systematic bias. The conclusion of a correlation between the spin and velocity vectors is independent of a bias introduced by subsets in the total sample. Moreover, we estimate that the observed alignment is robust to within 10% systematic uncertainties on the determination of the spin-axis direction from polarisation data.Comment: 20 pages, 7 figures, 1 Table, accepted in MNRA