Powered mobility interventions for very young children with mobility limitations to aid participation and positive development: the EMPoWER evidence synthesis

BACKGROUND

One-fifth of all disabled children have mobility limitations. Early provision of powered mobility for very young children (aged < 5 years) is hypothesised to trigger positive developmental changes. However, the optimum age at which to introduce powered mobility is unknown.

OBJECTIVE

The aim of this project was to synthesise existing evidence regarding the effectiveness and cost-effectiveness of powered mobility for very young children, compared with the more common practice of powered mobility provision from the age of 5 years.

REVIEW METHODS

The study was planned as a mixed-methods evidence synthesis and economic modelling study. First, evidence relating to the effectiveness, cost-effectiveness, acceptability, feasibility and anticipated outcomes of paediatric powered mobility interventions was reviewed. A convergent mixed-methods evidence synthesis was undertaken using framework synthesis, and a separate qualitative evidence synthesis was undertaken using thematic synthesis. The two syntheses were subsequently compared and contrasted to develop a logic model for evaluating the outcomes of powered mobility interventions for children. Because there were insufficient published data, it was not possible to develop a robust economic model. Instead, a budget impact analysis was conducted to estimate the cost of increased powered mobility provision for very young children, using cost data from publicly available sources.

DATA SOURCES

A range of bibliographic databases [Cumulative Index to Nursing and Allied Health Literature (CINHAL), MEDLINE, EMBASE™ (Elsevier, Amsterdam, the Netherlands), Physiotherapy Evidence Database (PEDro), Occupational Therapy Systematic Evaluation of Evidence (OTseeker), Applied Social Sciences Index and Abstracts (ASSIA), PsycINFO, Science Citation Index (SCI; Clarivate Analytics, Philadelphia, PA, USA), Social Sciences Citation Index™ (SSCI; Clarivate Analytics), Conference Proceedings Citation Index - Science (CPCI-S; Clarivate Analytics), Conference Proceedings Citation Index - Social Science & Humanities (CPCI-SSH; Clarivate Analytics), Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database (NHS EED), Health Technology Assessment (HTA) Database and OpenGrey] was systematically searched and the included studies were quality appraised. Searches were carried out in June 2018 and updated in October 2019. The date ranges searched covered from 1946 to September 2019.

RESULTS

In total, 89 studies were included in the review. Only two randomised controlled trials were identified. The overall quality of the evidence was low. No conclusive evidence was found about the effectiveness or cost-effectiveness of powered mobility in children aged either < 5 or ≥ 5 years. However, strong support was found that powered mobility interventions have a positive impact on children's movement and mobility, and moderate support was found for the impact on children's participation, play and social interactions and on the safety outcome of accidents and pain. 'Fit' between the child, the equipment and the environment was found to be important, as were the outcomes related to a child's independence, freedom and self-expression. The evidence supported two distinct conceptualisations of the primary powered mobility outcome, movement and mobility: the former is 'movement for movement's sake' and the latter destination-focused mobility. Powered mobility should be focused on 'movement for movement's sake' in the first instance. From the budget impact analysis, it was estimated that, annually, the NHS spends £1.89M on the provision of powered mobility for very young children, which is < 2% of total wheelchair service expenditure.

LIMITATIONS

The original research question could not be answered because there was a lack of appropriately powered published research.

CONCLUSIONS

Early powered mobility is likely to have multiple benefits for very young children, despite the lack of robust evidence to demonstrate this. Age is not the key factor; instead, the focus should be on providing developmentally appropriate interventions and focusing on 'movement for movement's sake'.

FUTURE WORK

Future research should focus on developing, implementing, evaluating and comparing different approaches to early powered mobility.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42018096449.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology programme and will be published in full in Health Technology Assessment; Vol. 24, No. 50. See the NIHR Journals Library website for further project information.

Psychological effects of centrally acting drugs in man; effects of chlorpromazine secobarbital on visual and motor behaviour

In a previous study (Kornetsky, Humphries and Evarts, 1957) it was found that the impairment of a variety of psychological processes caused by 200 mg. of chlorpromazine was not significantly less than the impairment produced by 200 mg. of secobarbital. It was also shown that the effects of drugs on psychological performance in man are related not only to the specific pharmacological activity of the drug, but also to the specific reactivity of the subject. It appeared that there was something unique to the individual which accounted for a significant portion of the effect of a drug. The present study was designed to extend these observations by reducing the number of drugs tested (in the previous study four drugs were used) and increasing the number of times a subject received each drug. It was hoped that this would give a better estimate of the effect of a specific dose of a specific drug and thus decrease the error of measurement and increase the reliability of the correlation between drugs.

Prolonged immobilization of the body: changes in performance and in the electroencephalogram

Subjects who were immobilized for a week but otherwise were exposed to a normal and varied sensory environment showed intellectual and perceptual deficits similar in many respects to those occurring after prolonged visual and auditory deprivation. A significant change in the electroencephalogram was also observed.

A property of second order differential equations with application to formal kinetics

It is shown that if x(t) is the solution of a second order differential equation, with real negative characteristic roots (not necessarily distinct), which exhibits an extremum at t = T, then T|x(T)|/|A| [UNK] 1/e where A is the area under the x(t) curve. This result is compared to a special case previously derived by M. Morales and applications of the theorem to formal kinetic problems are discussed.

MOTOR OUTPUT PATTERNS DURING RANDOM AND RHYTHMIC STIMULATION OF LOCUST THORACIC GANGLIA

This paper employs new statistical techniques to further analyze the flight control system of grasshoppers. The quantitative results confirm some hypotheses which arise from previous studies of this system. After decapitation and ablation of wing proprioceptors, stimulation of the nerve cord at random intervals can elicit a coordinated response closely resembling the normal flight motor output pattern. The coordinated response begins only after many stimuli and there are usually many cycles of after-discharge. The frequency of the cyclic output is rather low and may be increased only slightly by large increases in stimulus frequency. Input from the stretch receptors is necessary to attain normal wingstroke frequency. Frequency of wingbeat rises with a time constant of about 2 seconds (or about 25 wingbeats) when stretch receptor stimulation is initiated. Frequency decay after cessation of stimulation has about the same time constant. No special phase relationship between stimulation and output is necessary for the increase in frequency or maintenance of normal pattern. When input frequency is adjusted as closely as possible to output frequency it is still not possible to force the output to maintain a particular phase with respect to the stimulation, all phase relationships still occur. In some animals all phases occurred with equal probability; in others a particular phase was preferred. When there was a strong phase preference the normal output pattern was disrupted.

BEHAVIORAL-NEUROCHEMICAL CORRELATION IN REACTIVE AND NONREACTIVE STRAINS OF RATS

Male and female rats of the Maudsley reactive and Maudsley nonreactive strains were tested in the open-field to obtain ambulation and defecation scores. They were later killed, and their brains were dissected into five portions and analyzed for serotonin. Males defecated more and ambulated less than females, and nonreactive males ambulated more and defecated less than reactive males. These behavioral differences were significant (p .05). A statistically significant difference was found for the amounts of serotonin in specific regions of the brain between males and females (males higher) and between reactive and nonreactive males (reactive higher). Significant negative correlations between serotonin values in specific regions of brain and ambulation scores were found in these animals viewed as a group or even within a given strain and sex.

STUDIES ON CILIA. THE FIXATION OF THE METACHRONAL WAVE

Upon excision into spring water, the lateral cilia of the gill of the freshwater mussel Elliptio complanatus (Solander) stop beating, but 0.04 M potassium ion can activate the gill so that these cilia again beat with metachronal rhythm. One per cent osmium tetroxide quickly pipetted onto a fully activated gill fixes the lateral cilia in a pattern that preserves the form and arrangement of the metachronal wave, and permits the cilia to be studied with the electron microscope in all stages of their beat cycle. Changes are seen in the fixed active preparation that are not present in the inactive control, i.e., in the packing of the cilia, the position of the axis of the ciliary cross-section, and the diameter of the ring of peripheral filaments. Analysis of these parameters may lead to new correlations between ciliary fine structure and function.

DIFFERENTIAL GROWTH AND PHOTOTROPIC BENDING IN PHYCOMYCES

Using present knowledge of the cell's optical and growth mechanisms, a theoretical bending speed of about 5° min.^-1 is calculated for unilateral irradiation by a single beam of normally incident visible light; this figure is of the magnitude found experimentally. Between beams of light opposed at 180°, the resultant bending speed is given by the difference-to-sum ratio of the light intensities of the two beams. Valid comparisons between cells differing in size, growth speed, or optical properties are made by expressing bending speed as a fraction of each cell's bending response to unilateral irradiation. With multiple beams differing in intensity and azimuth, the resultant bending speed follows from vector addition of phototropic components proportional to the flux fraction of each beam. The bending speed in Oehlkers' experiment where a luminous area is the light source also appears compatible with this rule. In such experiments, the bending speed quantitatively matches the scaled asymmetry of the pattern of flux incident upon the cell. Resolution experiments support the assumption that light intensity enters into steady state phototropic formulations as the first power of I.

STEADY-STATE PHOTOTROPISM IN PHYCOMYCES

The steady-state phototropic bending of Phycomyces sporangiophores was studied using apparatus designed to keep the growing zone vertical and the angle of illumination constant over long periods of time. The bending speed is quite constant if the intensity and angle of illumination are fixed. A phototropic inversion occurs in response to a sudden change in intensity, either an increase or a decrease. A bending component lateral to the illumination direction is strongly evident at normal incidence. It is shown that this component is due to a rotation between the stimulus and response loci about the axis of the growing zone, which is probably related to the spiral growth of the cell. The steady-state bending speed is at a maximum value for illumination directions ranging from normal incidence to about 45 degrees . From 45 to 14 degrees the bending speed decreases linearly with angle, reaching zero at 14 degrees . Angles less than 14 degrees elicit a weak negative phototropic response. Using an optical model of the growing zone, the intracellular intensity distribution was determined as a function of the angle of illumination. Several hypotheses relating the intensity distribution to the phototropic response are discussed.

THE CYTOPLASMIC FINE STRUCTURE OF THE DIATOM, NITZSCHIA PALEA

The cytoplasmic fine structure of the motile, pennate diatom, Nitzschia palea was studied in thin sections viewed in the electron microscope. The cells were fixed in OsO(4), embedded in methacrylate, and immersed in 10 per cent hydrofluoric acid (HF) for 36 to 40 hours to remove the siliceous cell wall prior to sectioning. The HF treatment did not cause any obvious cytoplasmic damage. The dictyosome complex is perinuclear, and located only in the central cytoplasm. Mitochondria are sparse in the central cytoplasm, but abundant in the peripheral cytoplasm, and fill many of the transvacuolar cytoplasmic strands. Characteristic, amorphous oil bodies fill certain cytoplasmic strands and probably are not leucosin. The pyrenoid appears to be membrane limited, and oil droplets are found adjacent to the pyrenoid. The pyrenoid of another diatom, Cymbella affinis, is also membrane-limited. The membrane limiting the pyrenoid may be a composite of the terminal portions of chloroplast discs, facilitating rapid movement of photosynthate into the pyrenoid matrix, where the characteristic oil droplets may be formed. Carinal fibrils are found singly in each carinal pore, and may be involved in the locomotion of Nitzschia palea.