Edward Lemaire | Ottawa Hospital Research Institute (original) (raw)

Papers by Edward Lemaire

Knowledge mobilization can be hindered in healthcare technology settings where the pace of change... more Knowledge mobilization can be hindered in healthcare technology settings where the
pace of change outpaces the ability to perform high-quality research methodologies that
provide timely knowledge to enable informed prescription and technology application to
the end user. Although well-controlled research with appropriate sample sizes is needed,
this approach must be balanced with other evidence sources to address the knowledge immediacy
requirements. Using carbon-fibre ankle–foot orthoses (i.e., lower-limb braces
that improve stability, alignment, and foot-to-ground placement) as a case study, various
sources of assistive device evidence were explored for their contribution to the continuum
of knowledge in this area. A basic level of knowledge exists, but the quality is insufficient
to inform the physical rehabilitation community on selecting from the almost 70 different
devices on the market and the expected clinical outcomes for a target population. A combination
of enhanced single-participant reports should be considered as an important
part of the knowledge continuum and essential for knowledge immediacy. This approach
must also be expanded to national and multinational database initiatives that provide a
better base from which to extract knowledge on assistive device performance and mobilize
this knowledge to provide optimal care for people with physical disabilities.

Background: An optimal suspension system can improve comfort and quality of life in people with l... more Background: An optimal suspension system can improve comfort and quality of life in people with limb loss. To guide practice on prosthetic vacuum suspension systems, assessment of the current evidence and professional opinion are required. Methods: PubMed, Web of Science, and Google Scholar databases were explored to find related articles. Search terms were amputees, artificial limb, prosthetic suspension, prosthetic liner, vacuum, and prosthesis. The results were refined by vacuum socket or vacuum assisted suspension or sub-atmospheric suspension. Study design, research instrument, sample size, and outcome measures were reviewed. An online questionnaire was also designed and distributed worldwide among professionals and prosthetists (www.ispoint.org, OANDP-L, LinkedIn, personal email). Findings: 26 articles were published from 2001 to March 2016. The number of participants averaged 7 (SD = 4) for transtibial and 6 (SD = 6) for transfemoral amputees. Most studies evaluated the short-term effects of vacuum systems by measuring stump volume changes, gait parameters, pistoning, interface pressures, satisfaction, balance, and wound healing. 155 professionals replied to the questionnaire and supported results from the literature. Elevated vacuum systems may have some advantages over the other suspension systems, but may not be appropriate for all people with limb loss. Interpretation: Elevated vacuum suspension could improve comfort and quality of life for people with limb loss. However, future investigations with larger sample sizes are needed to provide strong statistical conclusions and to evaluate long-term effects of these systems.

Background and Aim: Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficul... more Background and Aim: Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficulties arise when working from the person’s socket since current 3D scanners have difficulties scanning socket interiors. While dedicated
scanners exist, they are expensive and the cost may be prohibitive for a limited number of scans per year. A low-cost and accessible photogrammetry method for socket interior digitization is proposed, using a smartphone camera and
cloud-based photogrammetry services.
Technique: 15 two-dimensional images of the socket’s interior are captured using a smartphone camera. A 3D model is generated using cloud-based software. Linear measurements were comparing between sockets and the related 3D models.
Discussion: 3D reconstruction accuracy averaged 2.6 ± 2.0 mm and 0.086 ± 0.078 L, which was less accurate than models obtained by high quality 3D scanners. However, this method would provide a viable 3D digital socket reproduction that
is accessible and low-cost, after processing in prosthetic CAD software.

Dual-task (DT) gait involves walking while simultaneously performing an attention-demanding task ... more Dual-task (DT) gait involves walking while simultaneously performing an attention-demanding task and can be used to identify impaired gait or executive function in older adults. Advancment is needed in techniques that quantify the influence of dual tasking to improve predictive and diagnostic potential. This study investigated the viability of wearable sensor measures to identify DT gait changes in older adults and distinguish between elderly fallers and non-fallers. A convenience sample of 100 older individuals (75.5 7 6.7 years; 76 non-fallers, 24 fallers based on 6 month retrospective fall occurrence) walked 7.62 m under single-task (ST) and DT conditions while wearing pressure-sensing insoles and tri-axial accelerometers at the head, pelvis, and left and right shanks. Differences between ST and DT gait were identified for temporal measures, acceleration descriptive statistics, Fast Fourier Transform (FFT) quartiles, ratio of even to odd harmonics, center of pressure (CoP) stance path coefficient of variation, and deviations to expected CoP stance path. Increased posterior CoP stance path deviations, increased coefficient of variation, decreased FFT quartiles, and decreased ratio of even to odd harmonics suggested increased DT gait variability. Decreased gait velocity and decreased acceleration standard deviations (SD) at the pelvis and shanks could represent compensatory gait strategies that maintain stability. Differences in acceleration between fallers and non-fallers in head posterior SD and pelvis AP ratio of even to odd harmonics during ST, and pelvis vertical maximum Lyapunov exponent during DT gait were identified. Wearable-sensor-based DT gait assessments could be used in point-of-care environments to identify gait deficits.

Maintaining and controlling postural balance is important for activities of daily living, with po... more Maintaining and controlling postural balance is important for activities of daily living, with poor postural balance being predictive of future falls. This study investigated eyes open and eyes closed standing posturography with elderly adults to identify differences and determine appropriate outcome measure cutoff scores for prospective faller, single-faller, multi-faller, and non-faller classifications. 100 older adults (75.5 ± 6.7 years) stood quietly with eyes open and then eyes closed while Wii Balance Board data were collected. Range in anterior-posterior (AP) and medial-lateral (ML) center of pressure (CoP) motion; AP and ML CoP root mean square distance from mean (RMS); and AP, ML, and vector sum magnitude (VSM) CoP velocity were calculated. Romberg Quotients (RQ) were calculated for all parameters. Participants reported six-month fall history and six-month post-assessment fall occurrence. Groups were retrospective fallers (24), prospective all fallers (42), prospective fallers (22 single, 6 multiple), and prospective non-fallers (47). Non-faller RQ AP range and RQ AP RMS differed from prospective all fallers, fallers, and single fallers. Non-faller eyes closed AP velocity, eyes closed VSM velocity, RQ AP velocity, and RQ VSM velocity differed from multi-fallers. RQ calculations were particularly relevant for elderly fall risk assessments. Cutoff scores from Clinical Cutoff Score, ROC curves, and discriminant functions were clinically viable for multi-faller classification and provided better accuracy than single-faller classification. RQ AP range with cutoff score 1.64 could be used to screen for older people who may fall once. Prospective multi-faller classification with a discriminant function (-1.481 + 0.146 x Eyes Closed AP Velocity—0.114 x Eyes Closed Vector Sum Magnitude Velocity—2.027 x RQ AP Velocity + 2.877 x RQ Vector Sum Magnitude Velocity) and cutoff score 0.541 achieved an accuracy of 84.9% and is viable as a screening tool for older people at risk of multiple falls.

— Wearable sensors can provide quantitative, gait-based assessments that can translate to point-o... more — Wearable sensors can provide quantitative, gait-based assessments that can translate to point-of-care environments. This investigation generated elderly fall-risk predictive models based on wearable-sensor-derived gait data and prospective fall occurrence; and identified the optimal sensor type, location, and combination for single and dual-task walking. 75 individuals who reported six month prospective fall occurrence (75.2 ± 6.6 years; 47 non-fallers, 28 fallers) walked 7.62 m under single-task and dual-task conditions while wearing pressure-sensing insoles and tri-axial accelerometers at the head, pelvis, and left and right shanks. Fall-risk classification models were assessed for all sensor combinations and three model types: neural network, naïve Bayesian, and support vector machine. The best performing model used a neural network, dual-task gait data, and input parameters from head, pelvis, and left shank accelerometers (accuracy = 57%, sensitivity = 43%, specificity = 65%). The best single-sensor model used a neural network, dual-task gait data, and pelvis accelerometer parameters (accuracy = 54%, sensitivity = 35%, specificity = 67%). Single-task and dual-task gait assessments provided similar fall-risk model performance. Fall-risk predictive models developed for point-of-care environments should use multi-sensor dual-task gait assessment with the pelvis location considered if assessment is limited to a single sensor.

Background: Wearable sensors can be used to derive numerous gait pattern features for elderly fal... more Background: Wearable sensors can be used to derive numerous gait pattern features for elderly fall risk and faller classification; however, an appropriate feature set is required to avoid high computational costs and the inclusion of irrelevant features. The objectives of this study were to identify and evaluate smaller feature sets for faller classification from large feature sets derived from wearable accelerometer and pressure-sensing insole gait data. Methods: A convenience sample of 100 older adults (75.5 ± 6.7 years; 76 non-fallers, 24 fallers based on 6 month retrospective fall occurrence) walked 7.62 m while wearing pressure-sensing insoles and tri-axial accelerometers at the head, pelvis, left and right shanks. Feature selection was performed using correlation-based feature selection (CFS), fast correlation based filter (FCBF), and Relief-F algorithms. Faller classification was performed using multi-layer perceptron neural network, naïve Bayesian, and support vector machine classifiers, with 75:25 single stratified holdout and repeated random sampling. Results: The best performing model was a support vector machine with 78% accuracy, 26% sensitivity, 95% specificity, 0.36 F1 score, and 0.31 MCC and one posterior pelvis accelerometer input feature (left acceleration standard deviation). The second best model achieved better sensitivity (44%) and used a support vector machine with 74% accuracy, 83% specificity, 0.44 F1 score, and 0.29 MCC. This model had ten input features: maximum, mean and standard deviation posterior acceleration; maximum, mean and standard deviation anterior acceleration; mean superior acceleration; and three impulse features. The best multi-sensor model sensitivity (56%) was achieved using posterior pelvis and both shank accelerometers and a naïve Bayesian classifier. The best single-sensor model sensitivity (41%) was achieved using the posterior pelvis accelerometer and a naïve Bayesian classifier. Conclusions: Feature selection provided models with smaller feature sets and improved faller classification compared to faller classification without feature selection. CFS and FCBF provided the best feature subset (one posterior pelvis accelerometer feature) for faller classification. However, better sensitivity was achieved by the second best model based on a Relief-F feature subset with three pressure-sensing insole features and seven head accelerometer features. Feature selection should be considered as an important step in faller classification using wearable sensors.

Wearable sensors have potential for quantitative, gait-based, point-of-care fall risk assessment ... more Wearable sensors have potential for quantitative, gait-based, point-of-care fall risk assessment that can be easily and quickly implemented in clinical-care and older-adult living environments. This investigation generated models for wearable-sensor based fall-risk classification in older adults and identified the optimal sensor type, location, combination, and modelling method; for walking with and without a cognitive load task. A convenience sample of 100 older individuals (75.5 ± 6.7 years; 76 non-fallers, 24 fallers based on 6 month retrospective fall occurrence) walked 7.62 m under single-task and dual-task conditions while wearing pressure-sensing insoles and tri-axial accelerometers at the head, pelvis , and left and right shanks. Participants also completed the Activities-specific Balance Confidence scale, Community Health Activities Model Program for Seniors questionnaire, six minute walk test, and ranked their fear of falling. Fall risk classification models were assessed for all sensor combinations and three model types: multi-layer perceptron neural network, naïve Bayesian, and support vector machine. The best performing model was a multi-layer perceptron neural network with input parameters from pressure-sensing insoles and head, pelvis, and left shank accelerometers (accuracy = 84%, F1 score = 0.600, MCC score = 0.521). Head sensor-based models had the best performance of the single-sensor models for single-task gait assessment. Single-task gait assessment models outperformed models based on dual-task walking or clinical assessment data. Support vector machines and neural networks were the best modelling technique for fall risk classification. Fall risk classification models developed for point-of-care environments should be developed using support vector machines and neural networks, with a multi-sensor single-task gait assessment.

— Static posturography can be used to assess pos-tural balance, which is important for activities... more — Static posturography can be used to assess pos-tural balance, which is important for activities of daily living. For older adults, poor postural balance can indicate increased fall risk. This study investigated eyes open and eyes closed static posturography assessments of 100 elderly participants (65 years) in two-feet stance. Twenty-four of these people had fallen in the previous six months. Range in anterior-posterior (AP) and medial-lateral (ML) motion; center of pressure (CoP) root mean square distance from mean; AP, ML, and resultant CoP velocity; and percent body weight on left and right feet were calculated from Wii Balance Board vertical force data. All AP measures and resultant CoP velocity were significantly greater with eyes closed than eyes open for fallers and non-fallers. ML CoP velocity was significantly greater with eyes closed than open for fallers. The largest percent increase from eyes open to eyes closed was for AP velocity, followed by 2D velocity for both fallers and non-fallers. Therefore, AP-based center of pressure-derived posturography measures appear to be sensitive to changes in postural control due to elimination of visual input. Significant differences were not found between fallers and non-fallers.

Static posturography can be used to assess postural balance, which is important for activities of... more Static posturography can be used to assess postural balance, which is important for activities of daily living. For older adults, poor postural balance can indicate increased fall risk. This study investigated eyes open and eyes closed static posturography assessments of 100 elderly participants ( 65 years) in two-feet stance. Twenty-four of these people had fallen in the previous six months. Range in anterior-posterior (AP) and medial-lateral (ML) motion; center of pressure (CoP) root mean square distance from mean; AP, ML, and resultant CoP velocity; and percent body weight on left and right feet were calculated from Wii Balance Board vertical force data.

Maintaining and controlling postural balance is important for activities of daily living, with po... more Maintaining and controlling postural balance is important for activities of daily living, with poor postural balance being predictive of future falls. This study investigated eyes open and eyes closed standing posturography with elderly adults to identify differences and determine appropriate outcome measure cut-off scores for prospective faller, single-faller, multi-faller, and non-faller classifications. 100 older adults (75.5 ± 6.7 years) stood quietly with eyes open and then eyes closed while Wii Balance Board data were collected. Range in anteriorposterior (AP) and medial-lateral (ML) center of pressure (CoP) motion; AP and ML CoP root mean square distance from mean (RMS); and AP, ML, and vector sum magnitude (VSM) CoP velocity were calculated. Romberg Quotients (RQ) were calculated for all parameters. Participants reported six-month fall history and six-month post-assessment fall occurrence. Groups were retrospective fallers (24), prospective all fallers (42), prospective fallers (22 single, 6 multiple), and prospective non-fallers (47). Non-faller RQ AP range and RQ AP RMS differed from prospective all fallers, fallers, and single fallers. Non-faller eyes closed AP velocity, eyes closed VSM velocity, RQ AP velocity, and RQ VSM velocity differed from multi-fallers. RQ calculations were particularly relevant for elderly fall risk assessments. Cut-off scores from Clinical Cut-off Score, ROC curves, and discriminant functions were clinically viable for multi-faller classification and provided better accuracy than singlefaller classification. RQ AP range with cut-off score 1.64 could be used to screen for older people who may fall once. Prospective multi-faller classification with a discriminant function (-1.481 + 0.146 x Eyes Closed AP Velocity-0.114 x Eyes Closed Vector Sum Magnitude Velocity-2.027 x RQ AP Velocity + 2.877 x RQ Vector Sum Magnitude Velocity) and cut-off score 0.541 achieved an accuracy of 84.9% and is viable as a screening tool for older people at risk of multiple falls.

Human activity recognition (HAR), using wearable sensors, is a growing area with the potential to... more Human activity recognition (HAR), using wearable sensors, is a growing area with the potential to provide valuable information on patient mobility to rehabilitation specialists. Smart-phones with accelerometer and gyroscope sensors are a convenient, minimally invasive, and low cost approach for mobility monitoring. HAR systems typically pre-process raw signals , segment the signals, and then extract features to be used in a classifier. Feature selection is a crucial step in the process to reduce potentially large data dimensionality and provide viable parameters to enable activity classification. Most HAR systems are custom-ized to an individual research group, including a unique data set, classes, algorithms, and signal features. These data sets are obtained predominantly from able-bodied participants. In this paper, smartphone accelerometer and gyroscope sensor data were collected from populations that can benefit from human activity recognition: able-bodied, elderly, and stroke patients. Data from a consecutive sequence of 41 mobility tasks (18 different tasks) were collected for a total of 44 participants. Seventy-six signal features were calculated and subsets of these features were selected using three filter-based, classifier-independent, feature selection methods (Relief-F, Correlation-based Feature Selection, Fast Correlation Based Filter). The feature subsets were then evaluated using three generic classifiers (Naïve Bayes, Support Vector Machine, j48 Decision Tree). Common features were identified for all three populations, although the stroke population subset had some differences from both able-bodied and elderly sets. Evaluation with the three classifiers showed that the feature subsets produced similar or better accuracies than classification with the entire feature set. Therefore, since these feature subsets are classifier-independent, they should be useful for developing and improving HAR systems across and within populations.

Gait & Posture, 2014

A self-paced treadmill automatically adjusts speed in real-time to match the user's walking speed... more A self-paced treadmill automatically adjusts speed in real-time to match the user's walking speed, potentially enabling more natural gait than fixed-speed treadmills. This research examined walking speed changes for able-bodied and transtibial amputee populations on a self-paced treadmill in a multi-terrain virtual environment and examined gait differences between fixed and self-paced treadmill speed conditions. Twelve able-bodied (AB) individuals and 12 individuals with unilateral transtibial amputation (TT) walked in a park-like virtual environment with level, slopes, and simulated uneven terrain scenarios. Temporal-spatial and range-of-motion parameters were analyzed.

Applied Ergonomics, 2016

Understanding how load carriage affects walking is important for people with a lower extremity am... more Understanding how load carriage affects walking is important for people with a lower extremity amputation who may use different strategies to accommodate to the additional weight. Nine unilateral traumatic transtibial amputees (K4-level) walked over four surfaces (level-ground, uneven ground, incline, decline) with and without a 24.5 kg backpack. Center of pressure (COP) and total force were analyzed from F-Scan insole pressure sensor data. COP parameters were greater on the intact limb than on the prosthetic limb, which was likely a compensation for the loss of ankle control. Double support time (DST) was greater when walking with a backpack. Although longer DST is often considered a strategy to enhance stability and/or reduce loading forces, changes in DST were only moderately correlated with changes in peak force. High functioning transtibial amputees were able to accommodate to a standard backpack load and to maintain COP progression, even when walking over different surfaces.

Background: Many occupations and hobbies require the use of a weighted pack. To date there has be... more Background: Many occupations and hobbies require the use of a weighted pack. To date there has been limited backpack gait studies performed on the amputee population. It is important that we address this knowledge gap in order to further improve individual's quality of living through changes in rehabilitation, and prosthesis development. Methods: The study population was ten male, unilateral, traumatic, K4-level (ability for prosthetic ambulation with high impact, stress, or energy levels), transtibial amputees. Ten walking trials were collected on level ground; five with a 24.5 kg backpack and five without a backpack. Temporal-spatial parameters and kinematic and kinetic peak values for the ankle, knee, hip, pelvis, and trunk were collected and analyzed for significant differences. Findings: Temporal-spatial parameters incurred changes that were congruent with the literature on able bodied individuals. Pelvis speeds and range of motion decreased with the pack. Knee flexion during weight acceptance increased, and was supported on the intact limb by increased eccentric knee power during weight acceptance. Hip flexion on both limbs also increased during weight acceptance while wearing the backpack. Interpretation: The backpack load can be accommodated by people at a K4 functional level for level ground walking. At the prosthetic limb, greater deformation was found at the foot-ankle and further increases in pack weight and higher impact tasks (i.e., jogging) could lead to decreased performance for some prosthetic feet. Gait training programs should focus on removing any gait asymmetries and increasing the strength of both the hip and knee flexors.

Prosthetics and orthotics international, Jan 24, 2015

For people with lower extremity amputations, the decreased confidence and suboptimal gait associa... more For people with lower extremity amputations, the decreased confidence and suboptimal gait associated with dynamic instability can negatively affect mobility and quality of life. Quantifying dynamic instability could enhance clinical decision making related to lower extremity prosthetics and inform future prosthetic research. To quantitatively examine gait adaptations in transfemoral amputees across various walking conditions. Cross-sectional study. Plantar-pressure data were collected from 11 individuals with unilateral transfemoral amputations using an in-shoe plantar-pressure measurement system while navigating rigid and soft ground, ramp, and stair conditions. Six parameters were examined: anterior-posterior and medial-lateral center-of-pressure direction changes, sensor cell loading frequency (cell triggering), maximum lateral force position, double support time, and stride time. Paired t-tests and analyses of variance were used to examine differences between limbs and walking c...

Gait & Posture, 2010

An improved understanding of factors related to dynamic stability in lower-limb prosthesis users ... more An improved understanding of factors related to dynamic stability in lower-limb prosthesis users is important, given the high occurrence of falls in this population. Current methods of assessing stability are unable to adequately characterize dynamic stability over a variety of walking conditions. F-Scan Mobile has been used to collect plantar pressure data and six extracted parameters were useful measures of dynamic stability. The aim of this study was to investigate dynamic stability in individuals with unilateral transtibial amputation based on these six parameters. Twenty community ambulators with a unilateral transtibial amputation walked over level ground, uneven ground, stairs, and a ramp while plantar pressure data were collected. For each limb (intact and prosthetic) and condition, six stability parameters related to plantar center-of-pressure perturbations and gait temporal parameters, were computed from the plantar pressure data. Parameter values were compared between limbs, walking condition, and groups (unilateral transtibial prosthesis users and able-bodied subjects). Differences in parameters were found between limbs and conditions, and between prosthesis users and able-bodied individuals. Further research could investigate optimizing parameter calculations for unilateral transtibial prosthesis users and define relationships between potential for falls and the dynamic stability measures.

Knowledge mobilization can be hindered in healthcare technology settings where the pace of change... more Knowledge mobilization can be hindered in healthcare technology settings where the pace of change outpaces the ability to perform high-quality research methodologies that provide timely knowledge to enable informed prescription and technology application to the end user. Although well-controlled research with appropriate sample sizes is needed, this approach must be balanced with other evidence sources to address the knowledge immediacy requirements. Using carbon-fibre ankle{\textendash}foot orthoses (i.e., lower-limb braces that improve stability, alignment, and foot-to-ground placement) as a case study, various sources of assistive device evidence were explored for their contribution to the continuum of knowledge in this area. A basic level of knowledge exists, but the quality is insufficient to inform the physical rehabilitation community on selecting from the almost 70 different devices on the market and the expected clinical outcomes for a target population. A combination of enhanced single-participant reports should be considered as an important part of the knowledge continuum and essential for knowledge immediacy. This approach must also be expanded to national and multinational database initiatives that provide a better base from which to extract knowledge on assistive device performance and mobilize this knowledge to provide optimal care for people with physical disabilities.

The Journal of Rehabilitation Research and Development, Feb 1, 2009

Persons with quadriceps muscle weakness are often prescribed a knee-ankle-foot orthosis that lock... more Persons with quadriceps muscle weakness are often prescribed a knee-ankle-foot orthosis that locks the knee in full extension during both stance and swing phases of gait. Locking the knee results in abnormal gait patterns characterized by hip hiking and leg circumduction during swing. The stance-control knee-ankle-foot orthosis (SCKAFO), a new type of orthosis, has emerged that permits free knee motion during swing while resisting knee flexion during stance, thereby supporting the limb during weight-bearing. This article examines various SCKAFO designs, discusses the existing design limitations, and identifes remaining design challenges. Several commercial SCKAFOs have been released that incorporate different locking mechanisms. Preliminary gait studies have shown some devices to be promising; however, an important functional limitation in some SCKAFOs is dependence on specific joint angles to switch between stance and swing modes. Important design factors such as size, weight, and noise must be considered in new orthosis designs to ensure wide consumer acceptance.

Maintaining and controlling postural balance is important for activities of daily living, with po... more Maintaining and controlling postural balance is important for activities of daily living, with poor postural balance being predictive of future falls. This study investigated eyes open and eyes closed standing posturography with elderly adults to identify differences and determine appropriate outcome measure cut-off scores for prospective faller, single-faller, multi-faller, and non-faller classifications. 100 older adults (75.5 ± 6.7 years) stood quietly with eyes open and then eyes closed while Wii Balance Board data were collected. Range in anteriorposterior (AP) and medial-lateral (ML) center of pressure (CoP) motion; AP and ML CoP root mean square distance from mean (RMS); and AP, ML, and vector sum magnitude (VSM) CoP velocity were calculated. Romberg Quotients (RQ) were calculated for all parameters. Participants reported six-month fall history and six-month post-assessment fall occurrence. Groups were retrospective fallers (24), prospective all fallers (42), prospective fallers (22 single, 6 multiple), and prospective non-fallers (47). Non-faller RQ AP range and RQ AP RMS differed from prospective all fallers, fallers, and single fallers. Non-faller eyes closed AP velocity, eyes closed VSM velocity, RQ AP velocity, and RQ VSM velocity differed from multi-fallers. RQ calculations were particularly relevant for elderly fall risk assessments. Cut-off scores from Clinical Cut-off Score, ROC curves, and discriminant functions were clinically viable for multi-faller classification and provided better accuracy than singlefaller classification. RQ AP range with cut-off score 1.64 could be used to screen for older people who may fall once. Prospective multi-faller classification with a discriminant function (-1.481 + 0.146 x Eyes Closed AP Velocity-0.114 x Eyes Closed Vector Sum Magnitude Velocity-2.027 x RQ AP Velocity + 2.877 x RQ Vector Sum Magnitude Velocity) and cut-off score 0.541 achieved an accuracy of 84.9% and is viable as a screening tool for older people at risk of multiple falls.

Gait & Posture, 2014

Applied Ergonomics, 2016

Prosthetics and orthotics international, Jan 24, 2015

Gait & Posture, 2010

Knowledge mobilization can be hindered in healthcare technology settings where the pace of change... more Knowledge mobilization can be hindered in healthcare technology settings where the pace of change outpaces the ability to perform high-quality research methodologies that provide timely knowledge to enable informed prescription and technology application to the end user. Although well-controlled research with appropriate sample sizes is needed, this approach must be balanced with other evidence sources to address the knowledge immediacy requirements. Using carbon-fibre ankle{\textendash}foot orthoses (i.e., lower-limb braces that improve stability, alignment, and foot-to-ground placement) as a case study, various sources of assistive device evidence were explored for their contribution to the continuum of knowledge in this area. A basic level of knowledge exists, but the quality is insufficient to inform the physical rehabilitation community on selecting from the almost 70 different devices on the market and the expected clinical outcomes for a target population. A combination of enhanced single-participant reports should be considered as an important part of the knowledge continuum and essential for knowledge immediacy. This approach must also be expanded to national and multinational database initiatives that provide a better base from which to extract knowledge on assistive device performance and mobilize this knowledge to provide optimal care for people with physical disabilities.

The Journal of Rehabilitation Research and Development, Feb 1, 2009