Mind your step: metabolic energy cost while walking an enforced gait pattern

The energy cost of walking could be attributed to energy related to the walking movement and energy related to balance control. In order to differentiate between both components we investigated the energy cost of walking an enforced step pattern, thereby perturbing balance while the walking movement is preserved. Nine healthy subjects walked three times at comfortable walking speed on an instrumented treadmill. The first trial consisted of unconstrained walking. In the next two trials, subject walked while following a step pattern projected on the treadmill. The steps projected were either composed of the averaged step characteristics (periodic trial), or were an exact copy including the variability of the steps taken while walking unconstrained (variable trial). Metabolic energy cost was assessed and center of pressure profiles were analyzed to determine task performance, and to gain insight into the balance control strategies applied. Results showed that the metabolic energy cost was significantly higher in both the periodic and variable trial (8% and 13%, respectively) compared to unconstrained walking. The variation in center of pressure trajectories during single limb support was higher when a gait pattern was enforced, indicating a more active ankle strategy. The increased metabolic energy cost could originate from increased preparatory muscle activation to ensure proper foot placement and a more active ankle strategy to control for lateral balance. These results entail that metabolic energy cost of walking can be influenced significantly by control strategies that do not necessary alter global gait characteristics.     

Impact of gender on asthma in childhood and adolescence: a GA2LEN review

A number of studies have shown gender differences in the prevalence of wheeze and asthma. The aim of this review was to examine published results on gender differences in childhood and adolescent asthma incidence and prevalence, define current concepts and to identify new research needs.
A Medline search was performed with the search words (gender OR sex) AND (child OR childhood OR adolescence) AND (asthma). Articles that reported on abscence or prescence of gender differences in asthma were included and reviewed, and cross-references were checked. Boys are consistently reported to have more prevalent wheeze and asthma than girls. In adolescence, the pattern changes and onset of wheeze is more prevalent in females than males. Asthma, after childhood, is more severe in females than in males, and is underdiagnosed and undertreated in female adolescents. Possible explanations for this switch around puberty in the gender susceptibility to develop asthma include hormonal changes and gender-specific differences in environmental exposures. This aspect needs consideration of the doctors and allergists who diagnose and treat asthmatic individuals.
In conclusion, sex hormones are likely to play an important role in the development and outcome of the allergic immune response and asthma in particular. By obtaining functional data from appropriate models, the exact underlying mechanisms can be unravelled. To examine the effect of gender-specific differences in environmental exposures and changes of asthma prevalence and severity in puberty, larger populations may need to be investigated.     

Validation and psychometric properties of the Delirium Motor Subtype Scale in elderly hip fracture patients (Dutch version)

The Delirium Motor Subtype Scale (DMSS) was developed to capture all the previous different approaches to delirium motor subtyping into one new instrument and emphasize disturbances of motor activity rather than associated psychomotoric symptoms. We investigated reliability and validity of the DMSS Dutch version. Elderly patients who had undergone hip fracture surgery received the DMSS and the Delirium Rating Scale Revised-98 (DRS-R-98). A diagnosis of delirium was defined according to the Confusion Assessment Method (CAM). Among 146 patients, 46 (32%) patients were diagnosed with delirium (mean age 86.3 years; SD 5.2). The internal consistency of the DMSS was acceptable (Cronbach's alpha = 0.72). If an item was removed at random the internal consistency of the scale remained the same. Similarly the concurrent validity of DMSS was good (Cohen's kappa = 0.73) while for each motor subtype the Cohen's kappa ranged from 0.58 to 0.85. The sensitivity and specificity of DMSS to detect each subtype ranged from 0.56 to 1 and from 0.88 to 0.98, respectively. This study suggests that the Dutch version of the DMSS is a reliable and valid instrument. The DMSS has scientific validity that could allow for greater precision in further research on motor subtypes.     

Getting ready for user involvement in a systematic review

Objective  This paper aims to support the critical development of user involvement in systematic reviews by explaining some of the theoretical, ethical and practical issues entailed in 'getting ready' for user involvement.
Background  Relatively few health or social care systematic reviews have actively involved service users. Evidence from other research contexts shows that user involvement can have benefits in terms of improved quality and outcomes, hence there is a need to test out different approaches in order to realize the benefits of user involvement and gain a greater understanding of any negative outcomes.
Design  Setting up a service-user reference group for a review of user involvement in nursing, midwifery and health visiting research involved conceptualizing user involvement, developing a representation framework, identifying and targeting service users and creating a sense of mutuality and reciprocity.
Setting and participants  Recruitment was undertaken across England by two researchers. Members from 24 national consumer organizations were selected to participate in the review.
Main variables studied  Learning was gained about finding ways of navigating consumer networks and organizations, how best to communicate our goals and intentions and how to manage selection and 'rejection' in circumstances where we had stimulated enthusiasm.
Results and conclusions  Involving service users helped us to access information, locate the findings in issues that are important to service users and to disseminate findings. User involvement is about relationships in social contexts: decisions made at the early conceptual level of research design affect service users and researchers in complex and personal ways.