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We present the results of combined INTEGRAL and XMM-Newton observations of the supergiant fast X-ray transient (SFXT) IGR J17354$-$3255. Three XMM-Newton observations of lengths 33.4 ks, 32.5 ks and 21.9 ks were undertaken, the first an initial pointing to identify the correct source in the field of view and the latter two performed around periastron. Simultaneous INTEGRAL observations across $\sim66\%$ of the orbital cycle were analysed but the source was neither detected by IBIS/ISGRI nor by JEM-X. The XMM-Newton light curves display a range of moderately bright X-ray activity but there are no particularly strong flares or outbursts in any of the three observations. We show that the spectral shape measured by XMM-Newton can be fitted by a consistent model throughout the observation, suggesting that the observed flux variations are driven by obscuration from a wind of varying density rather than changes in accretion mode. The simultaneous INTEGRAL data rule out simple extrapolation of the simple powerlaw model beyond the XMM-Newton energy range., Comment: 13 pages, 9 figures, This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society Published by Oxford University Press

XMM-Newton observations of the supergiant fast X-ray transient IGR$~$J17544$-$2619 are reported and placed in the context of an analysis of archival INTEGRAL/IBIS data that provides a refined estimate of the orbital period at 4.9272$\pm$0.0004 days. A complete outburst history across the INTEGRAL mission is reported. Although the new XMM-Newton observations (each lasting $\sim$15 ks) targeted the peak flux in the phase-folded hard X-ray light curve of IGR$~$J17544$-$2619, no bright outbursts were observed, the source spending the majority of the exposure at intermediate luminosities of the order of several 10$^{33}\,$erg$\,$s$^{-1}$ (0.5$\,-\,$10$\,$keV) and displaying only low level flickering activity. For the final portion of the exposure, the luminosity of IGR$~$J17544$-$2619 dropped to $\sim$4$\times$10$^{32}\,$erg$\,$s$^{-1}$ (0.5 - 10 keV), comparable with the lowest luminosities ever detected from this source, despite the observations being taken near to periastron. We consider the possible orbital geometry of IGR$~$J17544$-$2619 and the implications for the nature of the mass transfer and accretion mechanisms for both IGR$~$J17544$-$2619 and the SFXT population. We conclude that accretion under the `quasi-spherical accretion' model provides a good description of the behaviour of IGR$~$J17544$-$2619, and suggest an additional mechanism for generating outbursts based upon the mass accumulation rate in the hot shell (atmosphere) that forms around the NS under the quasi-spherical formulation. Hence we hope to aid in explaining the varied outburst behaviours observed across the SFXT population with a consistent underlying physical model., Comment: 12 pages, 5 figures, accepted for publication in MNRAS

We report on combined INTEGRAL and XMM-Newton observations of the supergiant fast X-ray transient IGR J16418-4532. The observations targeted the X-ray eclipse region of IGR J16418-4532s orbit with continuous INTEGRAL observations across ~25% of orbital phase and two quasi-simultaneous XMM-Newton observations of length 20ks and 14ks, occurring during and just after the eclipse respectively. An enhanced INTEGRAL emission history is provided with 19 previously unreported outbursts identified in the archival 18-60 keV data set. The XMM-Newton eclipse observation showed prominent Fe-emission and a flux of 2.8*10^-13 erg cm^-2 s^-1 (0.5 - 10 keV). Through the comparison of the detected eclipse and post eclipse flux, the supergiant mass loss rate through the stellar wind was determined as \dot{M}_{w} = 2.3-3.8*10^-7 M_{\odot} yr^-1. The post eclipse XMM-Newton observation showed a dynamic flux evolution with signatures of the X-ray pulsation, a period of flaring activity, structured nH variations and the first ever detection of an X-ray intensity dip, or 'off-state', in a pulsating supergiant fast X-ray transient. Consideration is given to the origin of the X-ray dip and we conclude that the most applicable of the current theories of X-ray dip generation is that of a transition between Compton cooling dominated and radiative cooling dominated subsonic accretion regimes within the 'quasi-spherical' model of wind accretion. Under this interpretation, which requires additional confirmation, the neutron star in IGR J16418-4532 possesses a magnetic field of ~10^14 G, providing tentative observational evidence of a highly magnetised neutron star in a supergiant fast X-ray transient for the first time. The implications of these results on the nature of IGR J16418-4532 itself and the wider SFXT class are discussed., 17 pages, 10 figures, accepted for publication in MNRAS

Temporal analysis of INTEGRAL/IBIS data has revealed a 5.7195\pm0.0007 day periodicity in the supergiant fast X-ray transient (SFXT) source AX J1845.0-0433, which we interpret as the orbital period of the system. The new-found knowledge of the orbital period is utilised to investigate the geometry of the system by means of estimating an upper limit for the size of the supergiant (, 6 pages, 6 figures, accepted for publication in MNRAS

Before developing new medical facilities or adapting existing facilities in the field of stroke, it is desirable to assess not only the medical, but also the economic consequences of such facilities. Economic evaluation studies differ from other outcome studies in the way that costs are compared with effects. The purpose of this paper is to give an insight into economic evaluation studies in the field of stroke, so that these studies become easier for neurologists to understand and to apply.Crucial aspects in economic evaluation research are addressed successively, such as the techniques used and how the results can be influenced by the perspective of the study. The article also considers the inclusion of costs and consequences in economic evaluation research. At the end of this article, special issues in economic evaluation studies are presented such as discounting, sensitivity analysis, incremental analyses and ratios.Although neurologists have no direct responsibility for allocating scarce resources in the field of stroke, they are confronted with the results of these decisions in their everyday work. Because of this, it might be useful to have clear understanding of economic evaluation studies and their caveats.

From a societal perspective long-term clinical trials or follow-up studies should preferably not only include an evaluation of the health effect for the patient, but also an economic evaluation. In order to yield comprehensive medical and nonmedical resource use data, we at least partly depend on respondents' recall for collecting these costing data. A patient cost diary was developed in order to estimate total resource use, expenses, and lost production due to illness and treatment. We applied the cost diary in two randomized clinical trials evaluating the cost-effectiveness of behavioral rehabilitation in 205 fibromyalgia and chronic low back pain patients. The use of the diary was evaluated, studying the feasibility, the influence of the period of data collection on the results, and some aspects of validity. Eighty-five percent of the patients completed at least one diary and in total 68% of the diaries were returned. Although the results for the three alternative periods of data collection (keeping the diary 1 week every month, 2 weeks every 2 months, or a full year) were not significantly different, they were only moderately correlated. Finally, self-reported specialist care contacts were generally in agreement with data from an insurance company. However, for physiotherapy contacts there were differences between the self-reported and insurance data. This study shows how the cost diary might be used successfully in cost-effectiveness studies.

This study examined the supplemental value of a cognitive coping skills training when added to an operant-behavioral treatment for chronic low-back pain patients. The complete treatment package (OPCO) was compared with an operant program + group discussion (OPDI) and a waiting-list control (WLC). After the WL period, the WLC patients received a less protocolized operant program usually provided in Dutch rehabilitation centers (OPUS). Regression analyses showed that, compared with WLC, both OPCO and OPDI led to less negative affect, higher activity tolerance, less pain behavior, and higher pain coping and pain control. At posttreatment, OPCO led to better pain coping and pain control than OPDI. Calculation of improvement rates revealed that OPCO and OPDI had significantly more improved patients than OPUS on all the dependent variables. The discussion includes findings regarding treatment credibility, compliance, and contamination bias.

The aim of this cost-effectiveness study was to compare a combined operant programme plus cognitive/relaxation programme with an operant programme plus attention-control and to compare both programmes with a waiting-list control group and with operant rehabilitation provided, as usual, by the same rehabilitation centre. One hundred and forty eight patients with chronic low back pain were randomly assigned to the different conditions. The economic endpoints were the costs of the programme and other health care utilisation, costs for the patient, and indirect costs associated with production losses due to low back pain. The effects were measured in terms of global assessment of change and utilities, using rating scale and standard gamble methods. The 3-year study determined that adding a cognitive component to an operant treatment did not lead to significant differences in costs and improvement in quality of life when compared with the operant treatment alone. Compared with the common individual rehabilitation therapy it can be concluded that the same effects can be reached at the same or lower costs with a shorter, more intense standardised group programme. The operant treatment alone is more effective than providing no treatment in the waiting-list control group.

In this 3 year randomized clinical trial the cost effectiveness of a 6 week educational/cognitive intervention (ECO) is compared with an educational discussion intervention (EDI) and a waiting list condition (WLC).A total of 131 patients with fibromyalgia were randomly allocated to the ECO, EDI, or WLC intervention. The ECO and EDI groups were followed for 12 months, whereas the WLC group was followed for 6 weeks. Direct health care and nonhealth care costs, and the indirect costs associated with lost production due to illness, were calculated. The effects were measured in terms of utilities, using rating scale and standard gamble methods.Treatment costs were estimated to be US $980 per patient for both ECO and EDI. The total direct health care costs of ECO treatment were US $1623 higher than those for EDI. This difference was significant. Indirect costs for the 2 groups were not significantly different. At 6 weeks there was a significant difference in rating scale utilities between the 3 groups, caused by a significantly greater improvement in the EDI group compared to the WLC group. However, no significant differences in either rating scale or standard gamble utilities were found between the ECO and EDI groups immediately after treatment, or at the 6 or 12 month followups.The economic evaluation showed that the addition of a cognitive component to the educational intervention led to significantly higher health care costs and no additional improvement in quality of life compared to the educational intervention alone. This conclusion is robust through a range of plausible values used in a sensitivity analysis.

This randomized controlled clinical trial evaluates the effectiveness of outpatient group cognitive/educational treatment for patients with the fibromyalgia (FM) syndrome. We hypothesized that the combination of group education with cognitive treatment aimed at developing pain coping skills would be more effective than group education alone.131 patients with FM were randomly assigned to 3 conditions: an experimental condition, which was the combined cognitive/educational intervention (ECO); an attention control condition consisting of group education plus group discussion (EDI); and a waiting list control (WLC). For the treatment conditions ECO and EDI, assessments were made 2 weeks before treatment, at start of treatment, at post-treatment, and at 6 and 12 mo followup. WLC patients received only 3 assessments.There were no pretreatment differences between the groups, or between dropouts and patients who remained in the study. At post-treatment, and compared with the WLC, the ECO patients improved in knowledge about FM (p = 0.007) and pain coping (p0.001). EDI patients improved on pain coping (p = 0.005) and pain control (p = 0.002). EDI patients reported significantly less fear than ECO patients (p = 0.005). There were no other differential effects between ECO and EDI at post-treatment or 6 mo or 12 mo followup. Based on the reliability of change index for clinical significance, the relative short term success rates are 6.4 and 18.4% for ECO and EDI, respectively.The surplus value of a highly structured, 12 session group cognitive treatment added to group education cannot be supported by our study. In EDI, fear reduction might have enhanced pain coping and pain control, while poor compliance, the difficulty of homework assignments, and lack of individual support may have limited the effectiveness of ECO.

We present the results of a 30ks XMM-Newton observation of the supergiant fast X-ray transient (SFXT) SAX J1818.6-1703 - the first in-depth soft X-ray study of this source around periastron. INTEGRAL observations shortly before and after the XMM-Newton observation show the source to be in an atypically active state. Over the course of the XMM-Newton observation, the source shows a dynamic range of ~100 with a luminosity greater than 1$\times$10$^{35}$ erg s$^{-1}$ for the majority of the observation. After an ~6 ks period of low luminosity (~10$^{34}$ erg s$^{-1}$) emission, SAX J1818.6-1703 enters a phase of fast flaring activity, with flares 250 s long, separated by ~2ks. The source then enters a larger flare event of higher luminosity and ~8 ks duration. Spectral analysis revealed evidence for a significant change in spectral shape during the observation with a photon index varying from {\Gamma} ~ 2.5 during the initial low luminosity emission phase, to {\Gamma} ~ 1.9 through the fast flaring activity, and a significant change to {\Gamma} ~ 0.3 during the main flare. The intrinsic absorbing column density throughout the observation (n$_H$ ~ 5$\times$10$^{23}$ cm$^{-2}$) is among the highest measured from an SFXT, and together with the XMM-Newton and INTEGRAL luminosities, consistent with the neutron star encountering an unusually dense wind environment around periastron. Although other mechanisms cannot be ruled out, we note that the onset of the brighter flares occurs at 3$\times$10$^{35}$ erg s$^{-1}$, a luminosity consistent with the threshold for the switch from a radiative-dominated to Compton cooling regime in the quasi-spherical settling accretion model., Comment: 11 pages, 8 figures, Accepted for publication in MNRAS