The European DISABKIDS project: development of seven condition-specific modules to measure health related quality of life in children and adolescents

BACKGROUND: The European DISABKIDS project aims to enhance the Health Related Quality of Life (HRQoL) of children and adolescents with chronic medical conditions and their families. We describe the development of the seven cross-nationally tested condition-specific modules of the European DISABKIDS HRQoL instrument in a population of children and adolescents. The condition-specific modules are intended for use in conjunction with the DISABKIDS chronic generic module. METHODS: Focus groups were used to construct the pilot version of the DISABKIDS condition-specific HRQoL modules for asthma, juvenile idiopathic arthritis, atopic dermatitis, cerebral palsy, cystic fibrosis, diabetes and epilepsy. Analyses were conducted on pilot test data in order to construct field test versions of the modules. A series of factor analyses were run, first, to determine potential structures for each condition-specific module, and, secondly, to select a reduced number of items from the pilot test to be included in the field test. Post-field test analyses were conducted to retest the domain structure for the final DISABKIDS condition-specific modules. RESULTS: The DISABKIDS condition-specific modules were tested in a pilot study of 360 respondents, and subsequently in a field test of 1152 respondents in 7 European countries. The final condition-specific modules consist of an 'Impact' domain and an additional domain (e.g. worry, stigma, treatment) with between 10 to 12 items in total. The Cronbach's alpha of the final domains was found to vary from 0.71 to 0.90. CONCLUSION: The condition-specific modules of the DISABKIDS instrument were developed through a step-by-step process including cognitive interview, clinical expertise, factor analysis, correlations and internal consistency. A cross-national pilot and field test were necessary to collect these data. In general, the internal consistency of the domains was satisfactory to high. In future, the DISABKIDS instrument may serve as a useful tool with which to assess HRQoL in children and adolescents with a chronic condition. The condition-specific modules can be used in conjunction with the DISABKIDS chronic generic module

Alertness and visuospatial attention in clinical depression

<p>Abstract</p> <p>Background</p> <p>Cognitive deficits are a substantial burden in clinical depression. The present study considered dysfunction in the right-hemispheric attention network in depression, examining alertness and visuospatial attention.</p> <p>Methods</p> <p>Three computerized visuospatial attention tests and an alertness test were administered to 16 depressive patients and 16 matched healthy controls.</p> <p>Results</p> <p>Although no significant group effect was observed, alertness predicted reduced visuospatial performance in the left hemifield. Furthermore, sad mood showed a trend towards predicting left visual field omissions.</p> <p>Conclusions</p> <p>Decreased alertness may lead to lower left hemifield visuospatial attention; this mechanism may be responsible for a spatial bias to the right side in depression, even though treatment of depression and anxiety may reduce this cognitive deficit.</p

Refined measurements of Henry’s law constant of terpenes with inert gas stripping coupled with PTR-MS

Henry’s law constant is an essential parameter for the estimation of the environmental prevalence of pollutants. Here, we present two improved methods for measuring Henry’s law constant deploying inert gas stripping (IGS). The methods are targeted at compounds with high gamma coefficients (activity coefficient at infinite dilution) corresponding to large infinite dilution coefficients, such as monoterpenes and sesquiterpenes. We deploy a highly sensitive PTR-MS (proton transfer reaction-mass spectrometer) (low limit of detection, wide linear range, split-second time resolution) as detector. We use suited off-equilibrium conditions to extrapolate to equilibrium conditions. The first method is based on the observed linear correlation between gas flow and off-equilibrium experimental Henry’s law constant value. The second method is based on the linear dependence of the gas holdup on volumetric flow. We report HLC constants for six monoterpenes, isoprene and even, as a proof of concept, the sesquiterpene farnesene. The new methods allow for measuring HLC of nearly insoluble compounds at a new accuracy and precisio

Proton Transfer Reaction-Mass Spectrometry (PTR-MS) as a tool for the determination of mass transfer coefficients

We present an alternative technique for the measurement of mass transfer coefficients for bubble columns from the gas phase with the mass spectrometric technique of Proton Transfer Reaction-Mass Spectrometry (PTR-MS). Instead of liquid phase measurements, we apply gas phase measurements of the effluent gas phase with the PTR-mass spectrometer. The method is based on the inert gas stripping approach for the determination of Henry's law constant. Therein gas is bubbled through a liquid-water- compound mix, and the declining concentration of the compound in the gas phase is measured over time. For the determination of the mass transfer coefficients, the concentration over time profile is used. Experiments for determination of mass transfer coefficients were carried out in small lab scale under controlled isothermal (thermostated) conditions and with a glass frit sparger. In principle this setup could be performed of fline with any detector that has a linear signal dependence over a wide concentration range. PTR-MS has the advantages of low limit of detection (ppt(v) – ppq(v)), wide linear range, and split second detection. We review the formulas for the determination of mass transfer coefficients. The relation with the equilibrium Henry's law constant is pointed out (extrapolation to origin considering gas holdup). We determine the overall volumetric mass transfer coefficient KLa, and moreover apply a method for the additional estimation of the liquid-side and gas-side mass transfer coefficients from KLa . Correlations of the superficial gas velocity to the gas holdup ε, the overall volumetric mass transfer coefficient KLa , the liquid side and gas phase volumetric side mass transfer coefficients kLa and kGa, as well as the ration kLa/ε are reported. The results demonstrate the suitability of PTR-MS to the determination of mass transfer coefficient for bubble column

Fragmentation of allylmethylsulfide by chemical ionization: dependence on humidity and inhibiting role of water

We report on a previously unknown reaction mechanism involving water in the fragmentation reaction following chemical ionization. This result stems from a study presented here on the humidity-dependent and energy-dependent endoergic fragmentation of allyl methyl sulfide (AMS) upon protonation in a proton transfer reaction-mass spectrometer (PTR-MS). The fragmentation pathways were studied with experimental (PTR-MS) and quantum chemical methods (polarizable continuum model (PCM), microhydration, studied at the MP2/6-311+G(3df,2p)//MP2/6-31G(d,p) level of theory). We report in detail on the energy profiles, reaction mechanisms, and proton affinities (G4MP2 calculations). In the discovered reaction mechanism, water reduces the fragmentation of protonated species in chemical ionization. It does so by direct interaction with the protonated species via covalent binding (C3H5+) or via association (AMS·H+). This stabilizes intermediate complexes and thus overall increases the activation energy for fragmentation. Water thereby acts as a reusable inhibitor (anticatalyst) in chemical ionization. Moreover, according to the quantum chemical (QC) results, when water is present in abundance it has the opposite effect and enhances fragmentation. The underlying reason is a concentration-dependent change in the reaction principle from active inhibition of fragmentation to solvation, which then enhances fragmentation. This amphoteric behavior of water is found for the fragmentation of C3H5+ to C3H3+, and similarly for the fragmentation of AMS·H+ to C3H5+. The results support humidity-dependent quantification efforts for PTR-MS and chemical ionization mass spectrometry (CIMS). Moreover, the results should allow for a better understanding of ion-chemistry in the presence of wate