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Patient satisfaction is a key indicator of inpatient care quality and is associated with clinical outcomes following admission. Different patient characteristics have been inconsistently linked with satisfaction. This study aims to overcome previous limitations by assessing which patient characteristics are associated with satisfaction within a large study of psychiatric inpatients conducted across five European countries.
All patients with a diagnosis of psychotic (F2), affective (F3) or anxiety/somataform (F4) disorder admitted to 57 psychiatric inpatient units in Belgium, Germany, Italy, Poland and the UK were included. Data were collected from medical records and face-to-face interviews, with patients approached within 2 days of admission. Satisfaction with inpatient care was measured on the Client Assessment of Treatment Scale.
Higher satisfaction scores were associated with being older, employed, living with others, having a close friend, less severe illness and a first admission. In contrast, higher education levels, comorbid personality disorder and involuntary admission were associated with lower levels of satisfaction. Although the same patient characteristics predicted satisfaction within the five countries, there were significant differences in overall satisfaction scores across countries. Compared to other countries, patients in the UK were significantly less satisfied with their inpatient care.
Having a better understanding of patient satisfaction may enable services to improve the quality of care provided as well as clinical outcomes for all patients. Across countries, the same patient characteristics predict satisfaction, suggesting that similar analytical frameworks can and should be used when assessing satisfaction both nationally and internationally.
A core question in the debate about how to organise mental healthcare is whether in- and out-patient treatment should be provided by the same (personal continuity) or different psychiatrists (specialisation). The controversial debate drives costly organisational changes in several European countries, which have gone in opposing directions. The existing evidence is based on small and low-quality studies which tend to favour whatever the new experimental organisation is.
We compared 1-year clinical outcomes of personal continuity and specialisation in routine care in a large scale study across five European countries.
This is a 1-year prospective natural experiment conducted in Belgium, England, Germany, Italy and Poland. In all these countries, both personal continuity and specialisation exist in routine care. Eligible patients were admitted for psychiatric in-patient treatment (18 years of age), and clinically diagnosed with a psychotic, mood or anxiety/somatisation disorder.
Outcomes were assessed 1 year after the index admission. The primary outcome was re-hospitalisation and analysed for the full sample and subgroups defined by country, and different socio-demographic and clinical criteria. Secondary outcomes were total number of inpatient days, involuntary re-admissions, adverse events and patients’ social situation. Outcomes were compared through mixed regression models in intention-to-treat analyses. The study is registered (ISRCTN40256812).
We consecutively recruited 7302 patients; 6369 (87.2%) were followed-up. No statistically significant differences were found in re-hospitalisation, neither overall (adjusted percentages: 38.9% in personal continuity, 37.1% in specialisation; odds ratio = 1.08; confidence interval 0.94–1.25; p = 0.28) nor for any of the considered subgroups. There were no significant differences in any of the secondary outcomes.
Whether the same or different psychiatrists provide in- and out-patient treatment appears to have no substantial impact on patient outcomes over a 1-year period. Initiatives to improve long-term outcomes of psychiatric patients may focus on aspects other than the organisation of personal continuity v. specialisation.
Debate exists as to whether functional care, in which different psychiatrists are responsible for in- and out-patient care, leads to better in-patient treatment as compared with sectorised care, in which the same psychiatrist is responsible for care across settings.
To compare patient satisfaction with in-patient treatment and length of stay in functional and sectorised care.
Patients with an ICD-10 diagnosis of psychotic, affective or anxiety/somatoform disorders consecutively admitted to an adult acute psychiatric ward in 23 hospitals across 11 National Health Service trusts in England were recruited. Patient satisfaction with in-patient care and length of stay (LoS) were compared (trial registration ISRCTN40256812).
In total, 2709 patients were included, of which 1612 received functional and 1097 sectorised care. Patient satisfaction was significantly higher in sectorised care (β = 0.54, 95% CI 0.35–0.73, P<0.001). This difference remained significant when adjusting for locality and patient characteristics. LoS was 6.9 days shorter for patients in sectorised care (β = −6.89, 95% CI –11.76 to −2.02, P<0.001), but this difference did not remain significant when adjusting for clustering by hospital (β = −4.89, 95% CI –13.34 to 3.56, P = 0.26).
This is the first robust evidence that patient satisfaction with in-patient treatment is higher in sectorised care, whereas findings for LoS are less conclusive. If patient satisfaction is seen as a key criterion, sectorised care seems preferable.
Improving the astrometric accuracy by one or two orders of magnitude over ground-based techniques will not only change our raw knowledge about the Galaxy, but it will also modify 1) the fundamental questions that can be addressed, and 2) the stellar dynamical concepts used so far. More detail in Galactic structure, such as the shape and flow in its putative bar, will be accessible. Also, with the instruments of the next generation the large scale dark matter distribution in the Galaxy, whether distributed in a spheroidal smooth halo or a massive outer disc made of cold clumpy gas, will be measurable. Techniques used for mapping the cosmic flow and mass distribution at Mpc scales and more might be applied to the solar neighbourhood to find the degree of clumpiness of the local matter distribution.
Two mechanisms involving purely dynamical processes can lead to the formation of a bulge after its disc: 1) small bulges (1 – 2 kpc), including box-shaped bulges and mildly triaxial bulges, can result from the formation and destruction of a bar; 2) big bulges (> 2kpc) à la Sombrero can grow following the accretion of small satellites. Fully consistent N-body simulations show that the fraction of galaxy mass accreted in this way needs to be larger than about 5%. Less accretion does not create smaller bulges, but heats the whole disc. These dynamical effects transforming Hubble types from SB to SA and vice-versa over ≈ 1 – 2 Gyr also indicate, by the secular growth of bulges, a general sense of galactic evolution from Sd to Sa.
A preliminary step towards the construction of self-consistent models for barred galaxies consists in understanding the stellar orbital behaviour in a given axisymmetrical + bar-like potential and, in particular, the influence of various parameters characterizing the bar on the different kinds of possible motions. To do this we undertook a systematic study of the main periodic and quasi-periodic orbits in a two-component mass model: An axisymmetrical part characterized by a rotation curve V(r) = Vo (r/ro)1-δ and a prolate bar-like perturbation whose density distribution is ρ = ρo (1-(x2+z2)/b2-y2/a2)2(a>b). This rather realistic choice for the bar is in agreement with the available photometric data and has several advantages, i.e. all cos(mθ) terms are included and the physical parameters such as the length of the bar a or its eccentricity e are explicitly included in the formulae. The ratio of bar to disk mass measured up to the outer Lindblad Resonance (ε) and the angular velocity (ωs) are also free parameters.
We measure quantitatively the growth of stochasticity due to various perturbations to a model of elliptical galaxy. This is achieved by computing the Liapunov characteristic exponents of randomly selected orbits.
The presence in the central few kpc of a disk galaxy of (1) a bar or a triaxial bulge, (2) a central mass concentration, and (3) a weak dissipation, make up the dynamical ingredients able to speed up considerably, (1) the thickening of the disk by vertical instabilities, and (2) the angular momentum losses, necessary to further accretion of mass. Some consequences compatible with observations are that bulges can be formed in large part after the disk formation phase, and that bars can be destroyed by a central mass concentration of about 109M⊙.
A mechanism for the destruction of rotating stellar bars by dissipative processes accreting mass at the center is tested by means of 3D N-body simulations (N ≈ 2·105)[2,3]. One or two ILR, originated from the growth of central mass concentration, cause the main elongated plane orbit family supporting the bar to be replaced by plane orbit families perpendicular to the bar, which can then no longer be sustained. The gas is represented in a crude way by a small (9%) set of particles contracting their phase-space with an ad-hoc friction law v̇ = −αv, where α is the inverse of a dissipation time scale. Typically, in a few Gyr an otherwise steady bar is transformed into a shorter, faster and weaker triaxial ellipsoid, similar to many bulges of normal spirals. These might be relics of destroyed bars. An example is shown in Fig. 2 where, after 8 Gyr, dissipation has brought 1.3% of the total mass inside 0.2 kpc, increasing the local average density by a factor of 14. The conservative case is represented in Fig. 1. The a/b/c axis ratios change from 1/0.54/0.55 to 1/0.74/0.60 at 1 kpc, and from 1/0.55/0.35 to 1/0.89/0.51 at 5 kpc. With a stronger dissipation (larger α) or equivalently at later time, the complete bar destruction seems unavoidable.
In this work, we explore a simple method with few free parameters, which describes the global dynamical consequences on disk galaxies of a slow cycling of gas between the interstellar, almost collisionless very cold gas and the warm collisional phases, with a secular transformation of a fraction of warm gas into stars.
We review the different cold dark gas models that have been proposed in the literature, as well as a new variant which addresses their principal stability problems by taking into account the property of molecular hydrogen to become solid or liquid below 33 K and at sufficiently high pressure. This new physical ingredient provides the possibility to stabilise cold gas globules by a core of condensed molecular hydrogen. Such loosely bound cold globules behave in a galaxy as a collisionless ensemble of matter, and form a reservoir of gas easily liberated through, e.g., UV excitation. the cold condensed cores survive the longest, of order a Gyr in the solar neighbourhood radiation field, and much longer in spiral outer HI disks.
To address, among other questions, puzzling observations about star forming in the extreme outer HI disk of M31 (Cuillandre et al. 2001), a scenario of interstellar gas cycling between the visible and a very cold invisible phase is investigated. The key new element sketched here, allowing to maintain the bulk of the gas out of sight, is that molecular hydrogen becomes liquid or solid below 33 K at sufficiently high pressure, allowing AU-sized spheres of very cold gas to be stabilised by incompressible cores of condensed H2 (Pfenniger 2004). These predicted cold gas globules are relatively weakly bound (~ 10−3eV/nucleon), such that their lifetime depends directly on the ambient UV/CR excitation level. At galactic scale the globules behave as collisionless bodies, and evaporate and become the usual visible ISM gas through heating. Much of the ISM gas can thus spend a long time in this cold condensed phase in low excitation regions. N-body simulations of galactic disks modeling such effects have been run, and some of their features are described in more detail in this volume and elsewhere (Revaz & Pfenniger 2004).
Non-axisymmetric gravitational potentials are likely to play an important role in generating central activity in galaxies, i.e. starbursts and/or active galactic nuclei (AGN). For instance, the often observed secondary bars embedded in larger, primary, ones (Friedli & Martinet 1993; Wozniak et al. 1995; Friedli et al. 1996) might play a key role in feeding AGN, by accreting gas down to the centre at scales of a few parsecs. On the other hand, the frequent presence of a nuclear ring of star formation located between both bars indicates that double-barred galaxies are intimately linked to the formation of some circumnuclear starbursts. This type of galaxies might give useful clues to the connection between starbursts and AGN.
Below, as part of a larger sample of nearby barred galaxies (Wozniak et al. 1997a) being taken by ISOCAM on board of the ISO satellite, we briefly discuss the characteristics of the circumnuclear mid-infrared (MIR) emission of two double-barred galaxies, namely NGC 4321 (M100) and NGC 1097. The observations were done using LW2 (5–8.5μm) and LW3 (12–18μm) broad band filters at the 1.5″ px−1 PFOV.
A single merger scenario for making galaxies such as NGC 4550 possessing equal coplanar counter-rotating stellar disks is investigated by collisionless N-body technique. The scenario is successful in producing an axisymmetric disk made of two almost equal counter-rotating populations. The final disk shows a clear bimodal line profile in the outer part, which demonstrates that disk-disk mergers do not always produce ellipticals.
While the existence of a central bar in our Galaxy now seems to be well established, its parameters (such as position angle, extension, axis ratio, angular speed etc…) still remain controversial. The large amount of photometrical and stellar kinematical data becoming now available within ∼ 30° of the Galactic Centre should provide potentially new constraints on these parameters. Unfortunately, a detailed barred model of the Milky Way, which would offer a powerful work frame to interpret such observations, does not exist yet. We therefore report here on a first attempt at constructing a 3D dynamically self-consistent barred model of the Galaxy. The idea is to follow the time evolution of a set of 400,000 particles initially distributed according to a plausible axisymmetric mass model of the Milky Way and in virial equilibrium, hoping that a bar will form spontaneously. Gas is not included so far, but will be introduced as a next step in this ongoing work. Some results presented at this meeting will be only quickly summarised here and explained in some more details elsewhere (Fux et al. 1995 and A&A paper in preparation).
The properties of chaos in 2D self-consistent models of barred galaxies are investigated using Kolmogorov-Sinai entropy hKS. These models are constructed with Schwarzschild’s method which combines orbits as elementary building blocks.
Most models are dominated by chaos near the 2/3 of the length of the bar and close to corotation. These locations correspond to regions where star-forming HII regions are observed because gas clouds could shock, shrink and fragment such that star formation could be ignited.
The model the most similar to N-body models shows a peak of hKS between the corners of the rectangular-like x1 orbits and the maximum extension points of the Lagrangian orbits. This emphasizes the role of Lagrangian orbits in the morphology of bars. Most models essentially contain ‘semi-chaotic’ orbits confined inside the corotation.
Recent observational constraints restrict the strict applicability of stellar dynamics in spirals to a few rotation periods. However, stellar dynamics concepts such as periodic orbits are invaluable for understanding the various dynamical processes occurring during much more periods. A distinction of two instability types in stellar systems is pointed out, the first one being well illustrated by the bar instability, and the second one by the bar bending instability. In bars the third dimension brings essential dynamical effects which modify the views about the history of bulges and the spiral secular evolution. Bars may grow, bend, thicken, and dissolve into spheroidal bulges, and spirals may evolve along the Hubble sequence in the sense Sd→Sa. This leads to a much more dynamical picture of isolated galaxies than imagined before.