Budget impact analysis of a Lifestyle-integrated Functional Exercise (LiFE) program for older people in Germany: a Markov model based on data from the LiFE-is-LiFE trial.

BACKGROUND: Fall prevention is important for healthy ageing, but the economic impact of fall prevention are scarcely investigated. A recent cost-effectiveness analysis compared a group-delivered Lifestyle-integrated Functional Exercise Program (gLiFE) with an individually-delivered program (LiFE) in community-dwelling people (aged ≥ 70 years) at risk of falling. In addition, the current study aimed to analyze the budget impact of LiFE and gLiFE, compared with standard care in Germany. METHODS: A Markov model was developed to reflect falls and associated care needs for community-dwelling persons over 5 years. The intervention effects of LiFE and gLiFE were shown to be equivalent in a non-inferiority trial, although the costs differed. Outpatient, inpatient, and intervention costs were assessed from a payer's perspective. The effect of parameter uncertainty was assessed in sensitivity analyses. RESULTS: The budget impact due to intervention costs was €510 million for LiFE and €186 million for gLiFE. Over five years, health care expenditures were €35,008 million for those receiving standard care, €35,416 million for those receiving LiFE, and €35,091 million for persons receiving gLiFE. Thereby, LiFE and gLiFE could prevent 2700 deaths and 648,000 falls over 5 years. Parameter uncertainties in the risk of falling, uptake of an intervention offer, and in the intervention effects had a major influence; thus cost savings for LiFE and gLiFE compared with standard care could be achieved for individuals with a high risk of falling. CONCLUSIONS: The results revealed that cost savings for LiFE and gLiFE compared with standard care could only be achieved for individuals at high risk of falling, with gLiFE being superior to LiFE. Future research should consider benefits and aspects of fall prevention beyond falls (e.g., physical activity, social aspects, and personal preferences of participants). TRIAL REGISTRATION: The study was preregistered under underclinicaltrials.gov (identifier: NCT03462654) on 12th March 2018; https://clinicaltrials.gov/ct2/show/NCT03462654 .

Comparison of falls and cost-effectiveness of the group versus individually delivered Lifestyle-integrated Functional Exercise (LiFE) program: final results from the LiFE-is-LiFE non-inferiority trial.

BACKGROUND: the individually delivered Lifestyle-integrated Functional Exercise (LiFE) was shown to improve physical activity (PA) and reduce fall incidence, however being rather resource-consuming due to one-to-one delivery. A potentially less resource-intensive group format (gLiFE) was developed and compared against the original program, considering higher risk of falling due to possible PA enhancement. OBJECTIVE: to investigate non-inferiority in terms of PA-adjusted fall risk and cost-effectiveness of gLiFE at 12-month follow-up. DESIGN: single-blinded, randomised, multi-centre non-inferiority trial. SETTING: community. SUBJECTS: in total, 309 adults aged 70+ years at risk of or with history of falling; n = 153 in gLiFE, n = 156 in LiFE. METHODS: LiFE was delivered one-to-one at the participants' homes, gLiFE in a group. PA-adjusted fall risk was analysed using negative binomial regression to compare incidence rate ratios (IRR). Cost-effectiveness was presented by incremental cost-effectiveness ratios and cost-effectiveness acceptability curves, considering quality-adjusted life years, PA and falls as effect measures. Secondary analyses included PA (steps/day) and fall outcomes. RESULTS: non-inferiority was inconclusive (IRR 0.96; 95% confidence interval, CI 0.67; 1.37); intervention costs were lower for gLiFE, but cost-effectiveness was uncertain. gLiFE participants significantly increased PA (+1,090 steps/day; 95% CI 345 and 1.835) versus insignificant increase in LiFE (+569, 95% CI -31; 1,168). Number of falls and fallers were reduced in both formats. CONCLUSION: non-inferiority of gLiFE compared with LiFE was inconclusive after 12 months. Increases in PA were clinically relevant in both groups, although nearly twice as high in gLiFE. Despite lower intervention costs of gLiFE, it was not clearly superior in terms of cost-effectiveness.

Changes in Psychological Determinants of Behavior Change after Individual versus Group-Based Lifestyle-integrated Fall Prevention: Results from the LiFE-is-LiFE Trial.

OBJECTIVE: The Lifestyle-integrated Functional Exercise (LiFE) intervention has been shown to promote physical activity in fall-prone older adults. However, the underlying mechanisms of how LiFE functions remain unclear. This study compares the effects of the individual and group-based LiFE formats on psychological determinants of behavior change derived from the health action process approach, habit formation theory, and self-determination theory. METHODS: Secondary analysis on basis of the randomized, non-inferiority LiFE-is-LiFE trial were performed. Questionnaire data on psychological determinants were obtained from older adults (M = 78.8 years, range 70-95) who took part in either the individual (n = 156) or the group-based (n = 153) LiFE intervention. Measurement points varied from three to six times, and from baseline (T1) up to a 12-month follow-up (T6). A generalized linear mixed model was specified for each determinant. RESULTS: Both LiFE and gLiFE participants reported lower levels of motivational determinants at T6. LiFE participants showed significantly higher values of action planning and coping planning at T6. Participants in both formats showed increased levels of action control at T6, whereas participants' habit strength decreased post-intervention but then stabilized over time. LiFE participants showed higher levels of autonomy, competence, and relatedness throughout the study, but levels of intrinsic motivation did not differ between formats and from T1 to T6. CONCLUSION: In both formats, but especially in the individual LiFE, the behavior change techniques used affected volitional rather than motivational or general determinants of behavior change. Habit strength as an important indicator of the sustainability of the LiFE exercises stabilized over time, indicating that participants, at least partly, sustained their formed habits long-term.

Reference equations for harmonizing gait speed results of different test protocols in community-dwelling older adults.

BACKGROUND AND AIMS: Different gait speed assessment protocols regarding start and stop of walking make comparison between studies impossible. The aim of this study was providing reference equations to estimate a person´s steady-state gait speed from gait speed measured with a test protocol including static start and/or stop. METHODS: Gait speed of 150 community-dwelling older adults (mean age 80.5 ± 4.5 years; 61% women) was measured over 4 m with different assessment protocols regarding start and stop of walking on an instrumented walkway. Reference equations to estimate steady-state gait speed from the results of other test protocols were calculated by regression analysis within a fivefold cross-validation. RESULTS: Mean absolute errors and the root mean squared errors of all reference equations ranged from 0.063 m/s to 0.074 m/s and 0.082 m/s to 0.096 m/s, respectively. CONCLUSIONS: The provided reference equations can help harmonizing results between studies in community-dwelling older adults.

Effect of a Passive Exosuit on Sit-to-Stand Performance in Geriatric Patients Measured by Body-Worn Sensors-A Pilot Study.

Standing up from a seated position is a prerequisite for any kind of physical mobility but many older persons have problems with the sit-to-stand (STS) transfer. There are several exosuits available for industrial work, which might be adapted to the needs of older persons to support STS transfers. However, objective measures to quantify and evaluate such systems are needed. The aim of this study was to quantify the possible support of an exosuit during the STS transfer of geriatric patients. Twenty-one geriatric patients with a median age of 82 years (1.-3.Q. 79-84 years) stood up at a normal pace (1) from a chair without using armrests, (2) with using armrests and (3) from a bed with pushing off, each condition with and without wearing an exosuit. Peak angular velocity of the thighs was measured by body-worn sensors. It was higher when standing up with exosuit support from a bed (92.6 (1.-3.Q. 84.3-116.2)°/s versus 79.7 (1.-3.Q. 74.6-98.2)°/s; p = 0.014) and from a chair with armrests (92.9 (1.-3.Q. 78.3-113.0)°/s versus 77.8 (1.-3.Q. 59.3-100.7)°/s; p = 0.089) compared to no support. There was no effect of the exosuit when standing up from a chair without using armrests. In general, it was possible to quantify the support of the exosuit using sensor-measured peak angular velocity. These results suggest that depending on the STS condition, an exosuit can support older persons during the STS transfer.

User Perspectives of Geriatric German Patients on Smart Sensor Technology in Healthcare.

With consideration of the progressing aging of our societies, the introduction of smart sensor technology can contribute to the improvement of healthcare for older patients and to reductions of the costs of care. From the clinical and medico-ethical points of view, the advantages of smart sensor technology are copious. However, any ethical evaluation of an introduction of a new technology in medical practice requires an inclusion of patients' perspectives and their assessments. We have conducted qualitative, semi-structured, exploratory interviews with 11 older patients in order to gain their subjective opinions on the use of smart sensor devices for rehabilitation purposes. The interviews were analyzed using methods of qualitative content and thematic analyses. In our analysis, we have focused on ethical aspects of adoption of this technology in clinical practice. Most of the interviewees expressed their trust in this technology, foremost because of its accuracy. Several respondents stated apprehension that the use of smart sensors will lead to a change in the patient-healthcare professional relationship. Regarding costs of introduction of smart sensors into healthcare, interviewees were divided between health insurance bearing the costs and individual participation in corresponding costs. Most interviewees had no concerns about the protection of their privacy or personal information. Considering these results, improvement of users' technology literacy regarding possible threats connected with putting smart sensors into clinical practice is a precondition to any individual application of smart sensors. This should occur in the form of extended and well-designed patient information adapted to individual levels of understanding. Moreover, application of smart sensors needs to be accompanied with careful anamnesis of patient's needs, life goals, capabilities, and concerns.

Mobility endpoints in marketing authorisation of drugs: what gets the European medicines agency moving?

BACKGROUND: Mobility is defined as the ability to independently move around the environment and is a key contributor to quality of life, especially in older age. The aim of this study was to evaluate the use of mobility as a decisive outcome for the marketing authorisation of drugs by the European Medicines Agency (EMA). METHODS: Fifteen therapeutic areas which commonly lead to relevant mobility impairments and alter the quantity and/or the quality of walking were selected: two systemic neurological diseases, four conditions primarily affecting exercise capacity, seven musculoskeletal diseases and two conditions representing sensory impairments. European Public Assessment Reports (EPARs) published by the EMA until September 2020 were examined for mobility endpoints included in their 'main studies'. Clinical study registries and primary scientific publications for these studies were also reviewed. RESULTS: Four hundred and eighty-four EPARs yielded 186 relevant documents with 402 'main studies'. The EPARs reported 153 primary and 584 secondary endpoints which considered mobility; 70 different assessment tools (38 patient-reported outcomes, 13 clinician-reported outcomes, 8 performance outcomes and 13 composite endpoints) were used. Only 15.7% of those tools distinctly informed on patients' mobility status. Out of 402, 105 (26.1%) of the 'main studies' did not have any mobility assessment. Furthermore, none of these studies included a digital mobility outcome. CONCLUSIONS: For conditions with a high impact on mobility, mobility assessment was given little consideration in the marketing authorisation of drugs by the EMA. Where mobility impairment was considered to be a relevant outcome, questionnaires or composite scores susceptible to reporting biases were predominantly used.

Willingness to pay for a group and an individual version of the Lifestyle-integrated Functional Exercise program from a participant perspective.

BACKGROUND: Perceived benefits of intervention programs from a participant perspective can be examined by assessing their willingness to pay (WTP). Aiming to support decision-makers in their decision to implement a fall prevention program, this study examined (1) the WTP for a group-based and an individually delivered fall prevention program, (2) which factors influence WTP, and (3) whether the WTP exceeds the intervention costs. METHODS: WTP was elicited using Payment Cards from 237 individuals who participated in a randomized non-inferiority trial (LiFE-is-LiFE) comparing a group version of the Lifestyle-integrated Functional Exercise program (gLiFE) with the individually delivered version (LiFE). Linear regression models were used to examine factors associated with WTP. The net benefit for (g)LiFE was calculated as the difference between WTP and intervention costs, assuming different scenarios of intervention costs (varying group sizes of gLiFE) and hypothetical subsidy levels by a payer (€0, €50, or €75). RESULTS: The mean WTP was €196 (95% CI [172, 221]) for gLiFE and €228 (95% CI [204, 251]) for LiFE. In the linear regression model, WTP was significantly associated with delivery format (-€32, 95% CI [- 65, - 0.2], for gLiFE) and net household income (+ 68€, 95% CI [23, 113], for ≥€3000 compared to <€2000). The net benefit for gLiFE was positive in most cases. Due to higher intervention costs of LiFE compared to gLiFE (€298 vs. €113), the net benefit for LiFE was negative for the majority of the sample, even at a subsidy of €75. CONCLUSION: The results provide insight into how valuable the interventions are perceived by the participants and thereby may be used by decision-makers as complement to cost-effectiveness analyses. WTP for both programs was generally high, probably indicating that participants perceived the intervention as quite valuable. However, further research is needed on the WTP and net benefit of fall prevention programs, as results relied on the specific context of the LiFE-is-LiFE trial.

Assessment of Thigh Angular Velocity by an Activity Monitor to Describe Sit-to-Stand Performance.

The assessment of sit-to-stand (STS) performance is highly relevant, especially in older persons, but testing STS performance in the laboratory does not necessarily reflect STS performance in daily life. Therefore, the aim was to validate a wearable sensor-based measure to be used under unsupervised daily life conditions. Since thigh orientation from horizontal to vertical is characteristic for STS movement, peak angular velocity (PAV) of the thigh was chosen as the outcome variable. A total of 20 younger and older healthy persons and geriatric patients (mean age: 55.5 ± 20.8 years; 55% women) with a wide range of STS performance were instructed to stand up from a chair at their usual pace. STS performance was measured by an activity monitor, force plates, and an opto-electronic system. The association between PAV measured by the thigh-worn activity monitor and PAV measured by the opto-electronic system (gold standard) was r = 0.74. The association between PAV measured by the thigh-worn activity monitor and peak power measured by force plate and opto-electronic system was r = 0.76. The Intra-Class Coefficient (ICC) of agreement between the 2 trials was ICC(A,1) = 0.76. In this sample of persons with a wide range of physical performance, PAV as measured by a thigh-worn acceleration sensor was a valid and reliable measure of STS performance.

Unlocking the black box of geriatric physiotherapy : Quantification of physical activity and walking parameters during inpatient geriatric rehabilitation therapy sessions.

BACKGROUND: Physiotherapy and occupational therapy are currently described using the duration of treatment (days or weeks), the frequency of therapy sessions (on a daily or 3-5 days per week basis) and considering the duration of a session (e.g., 30 or 45 min). The content is often poorly defined and the intensity is rarely reported. Using digital technology some of these shortcomings can be overcome. The cumulative parameters of walking and activity sessions, the duration of walking, the time spent in an upright or lying/sitting position and the number of steps can now be analyzed. In this study, we examined the parameters during non-treatment periods and therapy time in patients recovering from fragility fractures. METHODS: The study is a secondary data analysis of a trial that examined the improvement of physical activity (PA) and self-efficacy of fragility fracture patients. Changes in mobility parameters were measured using the ActivPal3 sensor during the 1st and 3rd weeks of rehabilitation and 104 patients were analyzed (mean age 82.5 years). Parameters included the time during supervised treatment, the mean number of steps, cumulative time in an upright position and walking duration, the number of walking intervals of > 10 s and sit to stand transfers. RESULTS: Patients received 3-4 therapy sessions adding up to 90-120 min per day. More than 50% of the daily walking activities were achieved in these sessions until discharge. With this amount of therapeutic input most parameters meaningfully improved from baseline to the second measurement. The number of steps increased by 30%, the mean time in an upright position increased by 26% and the mean time spent walking increased by 49%. CONCLUSION: The sensor-derived measurements describe the amount of walking activity administered during the supervised therapy sessions. This could be used as a starting point for future trials to improve the outcomes or as a standard of process evaluation for clinical services.

Lifestyle-integrated functional exercise to prevent falls and promote physical activity: Results from the LiFE-is-LiFE randomized non-inferiority trial.

BACKGROUND: The 'Lifestyle-integrated Functional Exercise' (LiFE) program successfully reduced risk of falling via improvements in balance and strength, additionally increasing physical activity (PA) in older adults. Generally being delivered in an individual one-to-one format, downsides of LiFE are considerable human resources and costs which hamper large scale implementability. To address this, a group format (gLiFE) was developed and analyzed for its non-inferiority compared to LiFE in reducing activity-adjusted fall incidence and intervention costs. In addition, PA and further secondary outcomes were evaluated. METHODS: Older adults (70 + years) at risk of falling were included in this multi-center, single-blinded, randomized non-inferiority trial. Balance and strength activities and means to enhance PA were delivered in seven intervention sessions, either in a group (gLiFE) or individually at the participant's home (LiFE), followed by two "booster" phone calls. Negative binomial regression was used to analyze non-inferiority of gLiFE compared to LiFE at 6-month follow-up; interventions costs were compared descriptively; secondary outcomes were analyzed using generalized linear models. Analyses were carried out per protocol and intention-to-treat. RESULTS: Three hundred nine persons were randomized into gLiFE (n = 153) and LiFE (n = 156). Non-inferiority of the incidence rate ratio of gLiFE was inconclusive after 6 months according to per protocol (mean = 1.27; 95% CI: 0.80; 2.03) and intention-to-treat analysis (mean = 1.18; 95% CI: 0.75; 1.84). Intervention costs were lower for gLiFE compared to LiFE (-€121 under study conditions; -€212€ under "real world" assumption). Falls were reduced between baseline and follow-up in both groups (gLiFE: -37%; LiFE: -55%); increases in PA were significantly higher in gLiFE (+ 880 steps; 95% CI 252; 1,509). Differences in other secondary outcomes were insignificant. CONCLUSIONS: Although non-inferiority of gLiFE was inconclusive, gLiFE constitutes a less costly alternative to LiFE and it comes with a significantly larger enhancement of daily PA. The fact that no significant differences were found in any secondary outcome underlines that gLiFE addresses functional outcomes to a comparable degree as LiFE. Advantages of both formats should be evaluated in the light of individual needs and preferences before recommending either format. TRIAL REGISTRATION: The study was preregistered under clinicaltrials.gov (identifier: NCT03462654 ) on March 12th 2018.

Association between everyday walking activity, objective and perceived risk of falling in older adults.

BACKGROUND: older persons can be grouped according to their objective risk of falling (ORF) and perceived risk of falling (PRF) into 'vigorous' (low ORF/PRF), 'anxious' (low ORF/high PRF), 'stoic' (high ORF/low PRF) and 'aware' (high ORF/PRF). Sensor-assessed daily walking activity of these four groups has not been investigated, yet. OBJECTIVE: we examined everyday walking activity in those four groups and its association with ORF and PRF. DESIGN: cross-sectional. SETTING: community. SUBJECTS: N = 294 participants aged 70 years and older. METHODS: ORF was determined based on multiple independent risk factors; PRF was determined based on the Short Falls Efficacy Scale-International. Subjects were allocated to the four groups accordingly. Linear regression was used to quantify the associations of these groups with the mean number of accelerometer-assessed steps per day over 1 week as the dependent variable. 'Vigorous' was used as the reference group. RESULTS: average number of steps per day in the four groups were 6,339 ('vigorous'), 5,781 ('anxious'), 4,555 ('stoic') and 4,528 ('aware'). Compared with the 'vigorous', 'stoic' (-1,482; confidence interval (CI): -2,473; -491) and 'aware' (-1,481; CI: -2,504; -458) participants took significantly less steps, but not the 'anxious' (-580 steps; CI: -1,440; 280). CONCLUSION: we have integrated a digital mobility outcome into a fall risk categorisation based on ORF and PRF. Steps per day in this sample of community-dwelling older persons were in accordance with their ORF rather than their PRF. Whether this grouping approach can be used for the specification of participants' needs when taking part in programmes to prevent falls and simultaneously promote physical activity remains to be answered in intervention studies.

Associations of sedentary behavior bouts with community-dwelling older adults' physical function.

The study aim was to explore associations between sedentary behavior (SB) bouts and physical function in 1360 community-dwelling older adults (≥65 years old). SB was measured using an ActiGraph wGT3X + accelerometer for seven consecutive days at the dominant hip and processed accordingly. Various SB bout lengths were assessed including: 1- to 9-minutes; 10- to 29-minutes; 30- to 59-minutes; and ≥60-minutes, as well as maximum time spent in a SB bout. Total SB time was adjusted for within the SB bout variables used (percentage SB time in the SB bout length and number of SB bouts per total SB hour). Physical function was assessed using the 2-minute walk test (2MWT), 5-times sit-to-stand (chair stand) test, and unipedal stance test (UST). Hierarchical linear regression models were utilized. Covariates such as moderate-vigorous physical activity (MVPA), demographic and health characteristics were controlled for. Lower percentage time spent in ≥60-minute SB bouts was significantly (P < .05) associated with longer 2MWT distance while lower numbers of ≥60-minute SB bouts were associated with longer 2MWT distance, shorter chair stand time and longer UST time. There were mixed associations with physical function for 10- to 29-minute SB bouts. In a large cohort of European older adults, prolonged SB bouts lasting ≥60-minutes appear to be associated with reduced physical function after controlling for MVPA and numerous other important covariates. Besides reducing SB levels, these findings suggest there is a need to regularly interrupt prolonged SB to improve physical function in older adults.

Estimate of gait speed by using persons' walk ratio or step-frequency in older adults.

BACKGROUND AND AIMS: Gait speed estimation using wearable inertial sensors during daily activities suffers from high complexity and inaccuracies in distance estimation when integrating acceleration signals. The aim of the study was to investigate the agreement between the methods of gait speed estimation using the persons' walk ratio (step-length/step-frequency relation) or step-frequency (number of steps per minute) and a "gold standard". METHODS: For this cross-sectional validation study, 20 healthy community-dwelling older persons (mean age 72.1 years; 70% women) walked at slow, normal, and fast speed over an instrumented walkway (reference measure). Gait speed was calculated using the person's pre-assessed walk ratio. Furthermore, the duration of walking and number of steps were used for calculation. RESULTS: The agreement between gait speed calculation using the walk ratio or step-frequency (adjusted to body height) and reference was r = 0.98 and r = 0.93, respectively. Absolute and relative mean errors of calculated gait speed using pre-assessed walk ratio ranged between 0.03-0.07 m/s and 1.97-4.17%, respectively. DISCUSSION AND CONCLUSIONS: After confirmation in larger cohorts of healthy community-dwelling older adults, the mean gait speed of single walking bouts during activity monitoring can be estimated using the person's pre-assessed walk ratio. Furthermore, the mean gait speed can be calculated using the step-frequency and body height and can be an additional parameter in stand-alone activity monitoring.

Template-Based Recognition of Human Locomotion in IMU Sensor Data Using Dynamic Time Warping.

Increased levels of light, moderate and vigorous physical activity (PA) are positively associated with health benefits. Therefore, sensor-based human activity recognition can identify different types and levels of PA. In this paper, we propose a two-layer locomotion recognition method using dynamic time warping applied to inertial sensor data. Based on a video-validated dataset (ADAPT), which included inertial sensor data recorded at the lower back (L5 position) during an unsupervised task-based free-living protocol, the recognition algorithm was developed, validated and tested. As a first step, we focused on the identification of locomotion activities walking, ascending and descending stairs. These activities are difficult to differentiate due to a high similarity. The results showed that walking could be recognized with a sensitivity of 88% and a specificity of 89%. Specificity for stair climbing was higher compared to walking, but sensitivity was noticeably decreased. In most cases of misclassification, stair climbing was falsely detected as walking, with only 0.2-5% not assigned to any of the chosen types of locomotion. Our results demonstrate a promising approach to recognize and differentiate human locomotion within a variety of daily activities.

Applying Social Cognition Models to Explain Walking Duration in Older Adults: The Role of Intrinsic Motivation.

This study examined the applicability of the health action process approach (HAPA) to walking duration in older adults and the added value of extending the HAPA by intrinsic motivation. Self-reports from older adults (N = 309; Mage = 78.7, 70-95 years) regarding activity-related intrinsic motivation and HAPA variables were collected at the baseline of a fall prevention intervention study. Walking duration at ≥3 metabolic equivalents of task was measured for 7 days via body-worn accelerometers. Two structural equation models with walking duration as a manifest outcome were specified. In both models, the model fit was acceptable, but intention and planning were not associated with walking duration. Intrinsic motivation was significantly related to most HAPA variables and walking duration. Variance explained for walking duration was R2 = .14 in the HAPA and R2 = .17 in the extended model. For explaining older adults' walking duration, intrinsic motivation, but not HAPA-based intention and planning, seemed to be important.

Perturbation in public transport as a basic concept for perturbation-based balance training for fall prevention.

INTRODUCTION: The aim of the study was to collect real-world sensor data on acceleration and deceleration while riding a bus or tram. With respect to the risk of suffering fall-related injuries while using public transportation, our interest was to understand the amplitude of real-world perturbations to translate them to innovative reactive balance training programs. METHODS: Acceleration and deceleration data were collected during 12 days in buses and trams in a German city. A sensor, which was fixed to a vertical bar in the vehicle, measured the acceleration signals. Additionally, extreme values of deceleration during full braking were collected in a driving school bus. RESULTS: For the incident type acceleration from standing extreme values of acceleration and jerking were higher in buses compared to trams with a maximum acceleration of 3.37 m/s2 and 1.80 m/s2, respectively, and extreme jerking of 13.30 m/s3 and -5.56 m/s3, respectively. Similarly, for the incident type deceleration approaching a stop extreme values of deceleration and jerking were higher in buses compared to trams with maximum deceleration of -3.12 m/s2 and -2.31 m/s2, respectively, and extreme jerking of -19.19 m/s3 and -10.83 m/s3, respectively. Extreme values for maximum deceleration and extreme jerking as simulated at the driving school were not reached during real-world measurements. The duration of incidents in acceleration from standing and deceleration approaching a stop was shorter for buses than for trams. CONCLUSION: Acceleration and jerking values were higher in buses compared to trams. Based on this study, laboratory simulation paradigms can be developed to study balance responses in older persons and to design fall prevention interventions which are ecologically valid.

Effects of an intervention to reduce fear of falling and increase physical activity during hip and pelvic fracture rehabilitation.

BACKGROUND: fear of falling and reduced fall-related self-efficacy are frequent consequences of falls and associated with poorer rehabilitation outcomes. To address these psychological consequences, geriatric inpatient rehabilitation was augmented with a cognitive behavioural intervention ("Step by Step") and evaluated in a RCT. METHODS: one hundred fifteen hip and pelvic fracture patients (age = 82.5 years, 70% female) admitted to geriatric inpatient rehabilitation were randomly allocated to the intervention or control group. The intervention consisted of eight additional individual sessions during inpatient rehabilitation, one home visit and four telephone calls delivered over 2 months after discharge. Both groups received geriatric inpatient rehabilitation. Primary outcomes were fall-related self-efficacy (short falls efficacy scale-international) and physical activity as measured by daily walking duration (activPAL3™ sensor) after admission to rehabilitation, before discharge and 1-month post-intervention. RESULTS: in covariance analyses, patients in the intervention group showed a significant improvement in fall-related self-efficacy (P = 0.025, d = -0.42), but no difference in total daily walking duration (P = 0.688, d = 0.07) 1-month post-intervention compared to the control condition. Further significant effects in favour of the intervention group were found in the secondary outcomes "perceived ability to manage falls" (P = 0.031, d = 0.41), "physical performance" (short physical performance battery) (P = 0.002, d = 0.58) and a lower "number of falls" (P = 0.029, d = -0.45). CONCLUSIONS: the intervention improved psychological and physical performance measures but did not increase daily walking duration. For the inpatient part of the intervention further research on the required minimum intensity needed to be effective is of interest. Duration and components used to improve physical activity after discharge should be reconsidered.

Mediating factors on the association between fear of falling and health-related quality of life in community-dwelling German older people: a cross-sectional study.

BACKGROUND: Previous research has shown that not only falls, but also fear of falling (FoF) influences health-related quality of life (HrQoL) negatively. The EQ-5D (consisting of an index and a visual analogue scale [EQ-VAS]) is a frequently used instrument to determine HrQoL in clinical studies and economic evaluations, but no previous study compared the association between FoF and the EQ-5D index with the association between FoF and the EQ-VAS. Moreover, factors that influence the association between FoF and HrQoL are rarely examined. Thus, this study aimed to examine the association between FoF and HrQoL and to examine factors that mediate the association. METHODS: FoF (Short Falls Efficacy Scale International) and HrQoL (EQ-5D descriptive system, EQ-5D index, and EQ-VAS) were assessed in a sample of community-dwelling older persons (≥70 years) participating in the baseline assessment of a randomized controlled trial (N = 309). Linear and logistic regression analyses were performed, adjusting for sociodemographic variables, frequency of falls, number of chronic conditions, functional mobility (Timed up-and-go test), and subjective functional capacity (LLFDI function and disability scales). Multiple regression models were used to test the mediating effects. RESULTS: Moderate or high FoF was prevalent in 66% of the sample. After adjusting for covariates, FoF was negatively associated with the EQ-5D index, but not with the descriptive system or the EQ-VAS. Subjective functional capacity partly mediated the association between FoF and the EQ-5D index and completely mediated the association between FoF and the EQ-VAS. CONCLUSION: FoF was negatively associated with the EQ-5D index. As subjective functional capacity mediated the association between FoF and HrQoL, future interventions should account for subjective functional capacity in their design.

Re-Enactment as a Method to Reproduce Real-World Fall Events Using Inertial Sensor Data: Development and Usability Study.

BACKGROUND: Falls are a common health problem, which in the worst cases can lead to death. To develop reliable fall detection algorithms as well as suitable prevention interventions, it is important to understand circumstances and characteristics of real-world fall events. Although falls are common, they are seldom observed, and reports are often biased. Wearable inertial sensors provide an objective approach to capture real-world fall signals. However, it is difficult to directly derive visualization and interpretation of body movements from the fall signals, and corresponding video data is rarely available. OBJECTIVE: The re-enactment method uses available information from inertial sensors to simulate fall events, replicate the data, validate the simulation, and thereby enable a more precise description of the fall event. The aim of this paper is to describe this method and demonstrate the validity of the re-enactment approach. METHODS: Real-world fall data, measured by inertial sensors attached to the lower back, were selected from the Fall Repository for the Design of Smart and Self-Adaptive Environments Prolonging Independent Living (FARSEEING) database. We focused on well-described fall events such as stumbling to be re-enacted under safe conditions in a laboratory setting. For the purposes of exemplification, we selected the acceleration signal of one fall event to establish a detailed simulation protocol based on identified postures and trunk movement sequences. The subsequent re-enactment experiments were recorded with comparable inertial sensor configurations as well as synchronized video cameras to analyze the movement behavior in detail. The re-enacted sensor signals were then compared with the real-world signals to adapt the protocol and repeat the re-enactment method if necessary. The similarity between the simulated and the real-world fall signals was analyzed with a dynamic time warping algorithm, which enables the comparison of two temporal sequences varying in speed and timing. RESULTS: A fall example from the FARSEEING database was used to show the feasibility of producing a similar sensor signal with the re-enactment method. Although fall events were heterogeneous concerning chronological sequence and curve progression, it was possible to reproduce a good approximation of the motion of a person's center of mass during fall events based on the available sensor information. CONCLUSIONS: Re-enactment is a promising method to understand and visualize the biomechanics of inertial sensor-recorded real-world falls when performed in a suitable setup, especially if video data is not available.