Cross-validation of cut-points in preschool children using different accelerometer placements and data axes

Acceptability, validity and responsiveness of inertial measurement units for assessing motor recovery after gene therapy in infants with early onset spinal muscular atrophy: a prospective cohort study

BACKGROUND

Onasemnogene abeparvovec gene replacement therapy (GT) has changed the prognosis of patients with spinal muscular atrophy (SMA) with variable outcome regarding motor development in symptomatic patients. This pilot study evaluates acceptability, validity and clinical relevance of Inertial Measurement Units (IMU) to monitor spontaneous movement recovery in early onset SMA patients after GT.

METHODS

Clinical assessments including CHOPINTEND score (the gold standard motor score for infants with SMA) and IMU measurements were performed before (M0) and repeatedly after GT. Inertial data was recorded during a 25-min spontaneous movement task, the child lying on the back, without (10 min) and with a playset (15 min) wearing IMUs. Two commonly used parameters, norm acceleration 95th centile (||A||_95) and counts per minute (||A||_CPM) were computed for each wrist, elbow and foot sensors.

RESULTS

23 SMA-patients were included (mean age at diagnosis 8 months [min 2, max 20], 19 SMA type 1, three type 2 and one presymptomatic) and 104 IMU-measurements were performed, all well accepted by families and 84/104 with a good child participation (evaluated with Brazelton scale). ||A||_95 and ||A||_CPM showed high internal consistency (without versus with a playset) with interclass correlation coefficient for the wrist sensors of 0.88 and 0.85 respectively and for the foot sensors of 0.93 and 0.91 respectively. ||A||_95 and ||A||_CPM were strongly correlated with CHOPINTEND (r for wrist sensors 0.74 and 0.67 respectively and for foot sensors 0.61 and 0.68 respectively, p-values < 0.001). ||A||_95 for the foot, the wrist, the elbow sensors and ||A||_CPM for the foot, the wrist, the elbow sensors increased significantly between baseline and the 12 months follow-up visit (respective p-values: 0.004, < 0.001, < 0.001, 0.006, < 0.001, < 0.001).

CONCLUSION

IMUs were well accepted, consistent, concurrently valid, responsive and associated with unaided sitting acquisition especially for the elbow sensors. This study is the first reporting a large set of inertial sensor derived data after GT in SMA patients and paves the way for IMU-based follow-up of SMA patients after treatment.

Evaluation of indoor activities for moderate-to-vigorous physical activity in preschoolers

The study objectives were 1) to determine the feasibility and acceptability of indoor activities to achieve moderate-to-vigorous physical activity (MVPA) in preschoolers, and 2) compare MVPA estimates between direct observation (DO) and various accelerometry placements. In this cross-sectional study, 35 preschoolers (51% female, 54% 3-year-olds) performed six, 6-minute activities (dancing to video, balloon/bubbles, stationary exergame cycling, circuits, running-in-place, and cleaning up) in sequential order, facilitated by a trained staff member. Triaxial accelerometers (Actigraph Gt3×BT) at the ankle, waist, and wrist measured MVPA using age-specific cut-points. Total activity and MVPA time were quantified via DO of video recordings. Feasibility and acceptability were assessed via parent and child report. Preschoolers contributed 4339, 15-second epochs of accelerometry and DO data (~31.0 minutes/preschooler). Preschoolers achieved MVPA ≥ 50% of the time while engaging in balloon/bubbles, cycling, and circuits; but not while dancing to video (15%), running-in-place (48.5%), or cleaning up (8%). There were no differences in MVPA by age, sex, or between screen and non-screen activities. Parents and preschoolers reported most activities were feasible (≥4.0/5.0). Waist and ankle accelerometry had strong agreement with DO (ICCs range: 0.70-0.84) while wrist had fair to low agreement (ICCs: 0.22-0.58). Multiple indoor activities show promise to increase preschoolers' MVPA.

The Day-Level Association Between Child Care Attendance and 24-Hour Movement Behaviors in Preschool-Aged Children

BACKGROUND

Twenty-four hour movement behaviors (ie, physical activity [PA], screen time [ST], and sleep) are associated with children's health outcomes. Identifying day-level contextual factors, such as child care, that positively influence children's movement behaviors may help identify potential intervention targets, like improving access to child care programs. This study aimed to examine the between- and within-person effects of child care on preschoolers' 24-hour movement behaviors.

METHODS

Children (N = 74, 4.7 [0.9] y, 48.9% girls, 63.3% White) wore an Axivity AX3 accelerometer on their nondominant wrist 24 hours per day for 14 days to measure PA and sleep. Parents completed surveys each night about their child's ST and child care attendance that day. Linear mixed effects models predicted day-level 24-hour movement behaviors from hours spent in child care.

RESULTS

Children spent an average of 5.0 (2.9) hours per day in child care. For every additional hour of child care above their average, children had 0.3 hours (95% CI, -0.3 to -0.2) less ST that day. Between-person effects showed that compared with children who attended fewer overall hours of child care, children who attended more hours had less overall ST (B = -0.2 h; 95% CI, -0.4 to 0.0). Child care was not significantly associated with PA or sleep.

CONCLUSIONS

Child care attendance was not associated with 24-hour PA or sleep; however, it was associated with less ST. More research utilizing objective measures of ST and more robust measures of daily schedules or structure is necessary to better understand how existing infrastructure may influence preschool-aged children's 24-hour movement behaviors. In addition, future research should consider how access to child care may influence child care attendance.

Calibration and validation of physical behaviour cut-points using wrist-worn ActiGraphs for children and adolescents: A systematic review

OBJECTIVES

To review cut-points calibrated and independently validated from wrist-worn ActiGraph accelerometers to measure moderate to vigorous physical activity (MVPA) and time spent sedentary (SED) in children and adolescents.

DESIGN

Systematic literature review.

METHODS

Five databases were searched for relevant cut-point calibration and independent validation studies relating to wrist worn ActiGraphs in children and adolescents from inception through 30 April 2022. Extracted data included: country of publication; study name; population; device model; wear location; sampling frequency; epoch length; activity protocol; criterion method and definitions used to classify PA intensity; statistical methods for calibration; statistical methods for validation/cross-validation; and MVPA and SED outcome.

RESULTS

Fourteen calibration studies and seven independent validation studies were identified. Calibrated cut-points for MVPA vector magnitude counts ranged from 7065 to 9204 counts per minute (cpm) and 63.5 to 201 milli-gravitational units (mg). For SED, calibrated cut-points ranged from <2556 cpm to 4350 cpm and 30.8 to 48.1 mg. Classification accuracy values determined by independent validation studies varied, with kappa values ranging from 0.31 to 0.60 and area under the curve statistics ranging from 0.51 to 0.84 for MVPA and kappa values ranging from 0.31 to 0.44 and area under the curve statistics ranging from 0.70 to 0.85 for SED.

CONCLUSIONS

The results of this systematic literature review support the use of the Crouter and colleagues cut-points for the measurement of MVPA and SED for children and adolescents aged 6-12 years. Further work is required to independently validate cut-points developed in younger children and older adolescents.

Physical Activity and Chronic Stress in Early Life: Findings From the 2015 Pelotas (Brazil) Birth Cohort

BACKGROUND

The association of physical activity through early childhood on children's chronic stress still is unclear. Therefore, the aim of the present study is to test the association of physical activity through early childhood (1-4 y) with chronic stress, measured by hair cortisol at age 4.

METHODS

Longitudinal study including children from the 2015 Pelotas (Brazil) Birth Cohort. Cortisol at age 4 was measured using a hair sample, which provided cortisol concentration from the past months. Physical activity was measured using accelerometers at 1, 2, and 4 years. Linear regression models were used to assess the association between physical activity and chronic stress. Trajectory models were also applied to examine chronic stress in relation to physical activity patterns throughout early childhood.

RESULTS

Children with valid physical activity and hair cortisol data were included in the analyses (N = 1475). Three groups of physical activity trajectories between 1 and 4 years were identified: low, medium, and high. No association between physical activity at 1, 2, and 4 years and chronic stress at age 4 was observed. However, children in the "high" physical activity trajectory presented low cortisol concentration; the magnitude of the regression coefficient was slightly larger in girls (β = -0.125; 95% confidence interval, -0.326 to 0.074) than boys (β = -0.051; 95% confidence interval, -0.196 to 0.09).

CONCLUSION

There was no clear association between physical activity and chronic stress in early childhood. Trajectories models suggest that higher activity throughout early childhood may positively impact chronic stress; however, more studies are needed to confirm that hypothesis.

Adherence to the World Health Organization's physical activity recommendation in preschool-aged children: a systematic review and meta-analysis of accelerometer studies

BACKGROUND

The World Health Organization (WHO) recommend that preschool-aged children should engage in 180 min of total physical activity (TPA) including 60 min of moderate-to-vigorous physical activity (MVPA) each day. No systematic reviews or meta-analyses have pooled adherence to the recommendation across multiple studies. This study aimed to estimate the prevalence of preschool-aged children achieving the WHO's physical activity recommendation for young children, and determine if the prevalence differed between boys and girls.

METHODS

Primary literature searches were conducted on six online databases and a machine learning assisted systematic review was used to identify relevant studies. Studies written in English reporting on the prevalence of children aged 3-5 years achieving overall WHO physical activity recommendation or the individual TPA or MVPA aspects of the recommendation measured using accelerometers were eligible for inclusion. Random effects meta-analysis was used to determine the prevalence of preschools achieving the overall WHO recommendation and the individual TPA and MVPA aspect of the recommendation, and to determine difference in prevalence between boys and girls.

RESULTS

Forty-eight studies reporting on 20,078 preschool-aged children met the inclusion criteria. Based on the most commonly employed accelerometer cut-points across all aspects of the recommendation, 60% (95% Confidence Interval [CI] = 37%, 79%) of preschool-aged children adhered to the overall physical activity recommendation, 78% (95% CI = 38%, 95%) adhered to the TPA aspect of the recommendation, and 90% (95% CI = 81%, 95%) adhered to the MVPA aspect of the recommendation. There was substantial variability is prevalence estimates between different accelerometer cut-points. Girls were significantly less likely to achieve the overall recommendation and the MVPA aspect of the recommendation than boys were.

CONCLUSIONS

Although there was substantial variability in estimated prevalence of preschool-aged children adhering the WHO physical activity recommendation between various accelerometer cut-points, the weight of available evidence suggests that the majority of young children are adhering to the overall recommendation and the individual TPA and MVPA aspects of the recommendation. Large-scale, intercontinental surveillance studies are needed to further strengthen the evidence regarding the prevalence of preschool-aged children achieving physical activity recommendation globally.

Methods recently used for the assessment of physical activity in children and adolescents

PURPOSE OF REVIEW

The aim of this review is to summarize recent evidences and advances on the implementation and the use of new tools to assessing physical activity (PA) in children.

RECENT FINDINGS

Technological advances provide, increasingly, new objective methods for the evaluation of PA in children. In addition to accelerometry, there are other objective methods for assessing PA in children such as new wearable monitoring and activity bracelets, smartphone and recording software applications, Global Positioning System or Inertial Sensors Devices.

SUMMARY

Doubly labeled water and calorimetry are reference methods to assessing PA but with limitations of use. Accelerometry is an accurate method for measuring sedentary behavior and PA levels in children. In fact, it is a real alternative reference method for the validation of methods and tools of assessing PA. However, there is still no consensus about the most appropriate approach to analyze the duration and intensity of PA in children. Therefore, the implementation of other alternative objective methods, as well as complementation with PA questionnaires, can provide a more precise evaluation of different patterns and behaviors related with sedentarism and PA.

Evaluating Outdoor Nature-Based Early Learning and Childcare Provision for Children Aged 3 Years: Protocol of a Feasibility and Pilot Quasi-Experimental Design

Systematic reviews have demonstrated the scarcity of well-designed evaluations investigating outdoor nature-based play and learning provision for children in the early learning and childcare (ELC) sector among global Western countries. This study will examine the feasibility and acceptability of the programme and the evaluation design of outdoor nature-based play and learning provision across urban ELC settings in a Scottish metropolitan city. Six ELC settings with different outdoor nature-based play delivery models will be recruited. One trial design will be tested: a quasi-experimental comparison of children attending three different models of outdoor play and learning provision. Measures will be assessed at baseline and five weeks later. Key feasibility questions include: recruitment and retention of ELC settings and children; suitability of statistical matching based on propensity score; completeness of outcome measures. Process evaluation will assess the acceptability of trial design methods and provision of outdoor nature-based play among ELC educators. These questions will be assessed against pre-defined progression criteria. This feasibility study will inform a powered effectiveness evaluation and support policy making and service delivery in the Scottish ELC sector.