Rates of attrition, non-compliance and missingness in randomized controlled trials of child physical activity interventions using accelerometers: A brief methodological review

Study Recruitment, Retention, and Adherence Among Chinese American Immigrants During the COVID-19 Pandemic

BACKGROUND

Chinese American immigrants have been underrepresented in health research partly due to challenges in recruitment.

OBJECTIVES

This study aims to describe recruitment and retention strategies and report adherence in a 7-day observational physical activity study of Chinese American immigrants with prior gestational diabetes during the COVID-19 pandemic.

METHODS

Foreign-born Chinese women aged 18-45 years, with a gestational diabetes index pregnancy of 0.5-5 years, who were not pregnant and had no current diabetes diagnosis were recruited. They wore an accelerometer for 7 consecutive days and completed an online survey. Multiple recruitment strategies were used: (a) culturally and linguistically tailored flyers, (b) social media platforms (e.g., WeChat [a popular Chinese platform] and Facebook), (c) near-peer recruitment and snowball sampling, and (d) a study website. Retention strategies included flexible scheduling and accommodation, rapid communications, and incentives. Adherence strategies included a paper diary and/or automated daily text reminders with a daily log for device wearing, daily email reminders for the online survey, close monitoring, and timely problem-solving.

RESULTS

Participants were recruited from 17 states; 108 were enrolled from August 2020 to August 2021. There were 2,479 visits to the study webpage, 194 screening entries, and 149 inquiries about the study. Their mean age was 34.3 years, and the mean length of U.S. stay was 9.2 years. Despite community outreach, participants were mainly recruited from social media (e.g., WeChat). The majority were recruited via near-peer recruitment and snowball sampling. The retention rate was 96.3%; about 99% had valid actigraphy data, and 81.7% wore the device for 7 days. The majority of devices were successfully returned, and the majority completed the online survey on time.

DISCUSSION

We demonstrated the feasibility of recruiting and retaining a geographically diverse sample of Chinese American immigrants with prior gestational diabetes during the COVID-19 pandemic. Recruiting Chinese immigrants via social media (e.g., WeChat) is a viable approach. Nonetheless, more inclusive recruitment strategies are needed to ensure broad representation from diverse socioeconomic groups of immigrants.

Pre-school-based behaviour change intervention to increase physical activity levels amongst young children: a feasibility cluster randomised controlled trial

Background

A significant rise in childhood obesity worldwide over the past three decades highlights the urgent need for early interventions, especially in preschools as key settings for child development. This study aimed to assess the feasibility and fidelity of a randomised controlled trial of "I'm an Active Hero" (IAAH), a theory- and evidence-based multi-component behaviour change intervention targeting physical activity and sedentary behaviour amongst preschool-aged children.

Methods

Two preschools in Taif city, Saudi Arabia were randomly assigned to either the intervention (n = 3 classrooms) or the usual curriculum control group (n = 3 classrooms). The intervention ran for 10 weeks from February to April 2023 and consisted of teacher-led physical activity and sedentary behaviour sessions in preschools, with an additional interactive home component. Primary outcome measures included intervention fidelity, recruitment rates, attrition rates, and compliance with trial procedures. Secondary outcomes included body mass index (BMI), objectively measured physical activity, and sedentary time via the ActiGraph GT3X accelerometer. Outcomes were measured at baseline and at 10 weeks in both study arms.

Results

The preschool intervention component had high fidelity (93.3%), but the home component fidelity was lower (74%). A cluster-level recruitment rate of 12% (13/112 centres) was attained, whilst the individual-level recruitment rate stood at 36% (52/143 children, mean age of 4.16 years; 23 girls). Attrition was 10%. Compliance varied with 90% for BMI, 71% for accelerometery, and 45% for questionnaires. The intervention group showed small decreases in BMI, slight increases in physical activity, and decreases in sedentary time at follow-up compared to the control group. Parents, facilitators, and assistant teachers considered the intervention to be feasible and beneficial.

Conclusion

The IAAH intervention was feasible to implement in Saudi Arabian preschools. Facilitators showed high fidelity in delivering it. However, preliminary data did not demonstrate effectiveness. A more comprehensive evaluation across a broader population is warranted. The intervention could be revised to optimise recruitment, compliance, and fidelity of the home-based component. Successful elements from this pilot should be retained whilst adaptations to implementation are made to strengthen key areas.Clinical trial registration: ClinicalTrials.gov, NCT05754359.

Exploring Factors Associated With Accelerometer Validity Among Ethnically Diverse Toddlers

PURPOSE

Studying physical activity in toddlers using accelerometers is challenging due to noncompliance with wear time (WT) and activity log (AL) instructions. The aims of this study are to examine relationships between WT and AL completion and (1) demographic and socioeconomic variables, (2) parenting style, and (3) whether sedentary time differs by AL completion.

METHODS

Secondary analysis was performed using baseline data from a community wellness program randomized controlled trial for parents with toddlers (12-35 mo). Parents had toddlers wear ActiGraph wGT3x accelerometers and completed ALs. Valid days included ≥600-minute WT. Analysis of variance and chi-square analyses were used.

RESULTS

The sample (n = 50) comprised racial and ethnically diverse toddlers (mean age = 27 mo, 58% male) and parents (mean age = 31.7 y, 84% female). Twenty-eight families (56%) returned valid accelerometer data with ALs. Participants in relationships were more likely to complete ALs (P < .05). Toddler sedentary time did not differ between those with ALs and those without.

CONCLUSIONS

We found varied compliance with WT instructions and AL completion. Returned AL quality was poor, presenting challenges in correctly characterizing low-activity counts to improve internal validity of WT and physical activity measures. Support from marital partners may be important for adherence to study protocols.

School-based physical activity interventions: which intervention characteristics are associated with participation and retention? A meta-analysis

OBJECTIVE

Many school-based intervention studies are conducted to increase students' physical activity (PA). Recruitment and retention problems potentially impact the robustness of RCT findings. We conducted a meta-analysis to summarize recruitment and retention rates in long-term secondary school-based PA intervention studies and examined associated participant and intervention characteristics.

METHODS

Web of Science, Pubmed, Medline, and PsychInfo were searched until March 20th 2023. We included studies on secondary school-based PA interventions ≥12 weeks, aimed at typically developing adolescents. We abstracted number of schools and students invited, randomized, and participating at follow-up to calculate pooled recruitment and retention rates; participant and intervention characteristics were abstracted to execute subgroup or meta-regression analyses.

RESULTS

Recruitment rates were 51% for invited schools and 80% for invited students, the retention for schools was almost 100% and for students 91%. Interventions with fixed and flexible components, executed in Asia and South America, and from later publication years had higher student recruitment rates. Students' retention rates were lower for interventions which had flexible components, were theory/model-based, used an accelerometer, had a longer intervention duration, and included more females.

CONCLUSION

Recruitment and retention rates in school-based PA interventions are high. Some participant and intervention characteristics influence these rates: flexibility of the intervention, theory/model-based intervention, accelerometer use, intervention duration, continent, and number of females. Researchers should consider these characteristics in intervention development to achieve optimal balance between intervention effectiveness, recruitment, and retention.

Wearable device adherence among insufficiently-active young adults is independent of identity and motivation for physical activity

Wearable devices are increasingly being integrated to improve prevention, chronic disease management and rehabilitation. Inferences about individual differences in device-measured physical activity depends on devices being worn long enough to obtain representative samples of behavior. Little is known about how psychological factors are associated with device wear time adherence. This study evaluated associations between identity, behavioral regulations, and device wear adherence during an ambulatory monitoring period. Young adults who reported insufficient physical activity (N = 271) were recruited for two studies before and after the SARS-COVID-19 pandemic declaration. Participants completed a baseline assessment and wore an Actigraph GT3X + accelerometer on their waist for seven consecutive days. Multiple linear regression indicated that wear time was positively associated with age, negatively associated with integrated regulation for physical activity, and greater after (versus before) the pandemic declaration. Overall, the model accounted for limited variance in device wear time. Exercise identity and exercise motivation were not associated with young adults' adherence to wearing the physical activity monitors. Researchers and clinicians can use wearable devices with young adults with minimal concern about systematic motivational biases impacting adherence to device wear.

Accelerometry-assessed daily physical activity and compliance with recommendations in Spanish children: importance of physical education classes and vigorous intensity

Background

Physical activity (PA) is associated with numerous health benefits. Vigorous PA (VPA) may have a greater impact on public health than lower-intensity PA. The incorporation of a specific recommendation on VPA could complement and improve existing recommendations for average daily moderate-vigorous PA (MVPA). Physical education classes could have a positive impact on children's adherence to average daily physical activity recommendations. The aim was to investigate the association between MVPA and VPA in children, as well as adherence to recommendations, and obesity and the presence of physical education classes.

Methods

A cross-sectional study of physical activity was conducted in a sample of 8 and 9-year-old children in Andalusia (Spain). GENEActiv accelerometers were used, placed on the non-dominant wrist for at least eight consecutive days (24-h protocol). School days with and without physical education class, and weekend days were defined. ROC curves were used to calculate the threshold associated with obesity for average daily MVPA and VPA for recommendations.

Results

A total of 360 schoolchildren were included in the analyses (184 girls). An average of 7.7 (SD 1.4) valid days per participant were evaluated, with 19.9 (SD 10.5) and 11.4 (SD 5.1) minutes of VPA performed by boys and girls respectively. 25.8% of the participants were classified with central obesity. The optimal threshold determined with ROC analysis was 12.5 and 9.5 minutes of average daily VPA for boys and girls, respectively (RecVPA), and 75 minutes of average daily MVPA for both sexes (RecMVPA). The RecVPA showed stronger association with obesity. On school days with physical education class, compared to days without this class, children showed increased VPA and MVPA engagement and better compliance with recommendations, with smaller differences in adherence according to sex or obesity.

Conclusions

On days with physical education class, more physical activity was accumulated at all intensities and greater adherence to the recommendations than on days without this class. VPA had a stronger correlation with the absence of obesity than lower-intensity activity. It was also observed that boys were physically more active and had higher adherence to the recommendations than girls.

'Including us, talking to us and creating a safe environment'-Youth patient and public involvement and the Walking In ScHools (WISH) Study: Lessons learned

BACKGROUND

Young people have the right to be informed and consulted about decisions affecting their lives. Patient and public involvement (PPI) ensures that research is carried out 'with' or 'by' young people rather than 'to', 'about' or 'for' them. The aim of this paper is to outline how youth PPI can be embedded within a physical activity intervention, reflect on the impact of PPI and provide recommendations for future PPI in a similar context.

METHODS

A Youth Advisory Group (YAG) was set up within the Walking In ScHools (WISH) Study to involve adolescent girls in the delivery, implementation and dissemination of a physical activity intervention targeted at adolescents. Schools invited pupils aged 12-14 years and 15-18 years to YAG meetings (n3, from 2019 to 2023). Participative methods were used to inform recruitment strategies and data collection methods for the WISH Study.

RESULTS

Across the three YAG meetings, n51 pupils from n8 schools were involved. Pupils enjoyed the YAG meetings, felt that their feedback was valued and considered the meetings a good way to get young people involved in research. The YAG advised on specific issues and although measuring impact was not the primary aim of the YAG meetings, over the course of the study there were many examples of the impact of PPI. Recruitment targets for the WISH Study were exceeded, the attrition rate was low and pupils were engaged in data collection.

CONCLUSION

Youth PPI is a developing field and there are few physical activity studies that report the PPI work undertaken. Within the WISH Study, three YAG meetings were held successfully, and the views of adolescent girls were central to the development of the study. Considering the specific issues that the YAG advised on (study recruitment, attrition and data collection), there was evidence of a positive impact of PPI.

PATIENT OR PUBLIC CONTRIBUTION

Pupils from post-primary schools interested/participating in the WISH Study were invited to attend YAG meetings. YAG meetings were set up to consult adolescent girls on the delivery, implementation and dissemination of the WISH intervention.

Effect of an activity wristband-based intermittent teaching unit in Physical Education on students' physical activity and its psychological mediators: a cluster-randomized controlled trial. School-fit study

Objective

The main objective of the present study was to examine the effects of an intermittent teaching unit based on the use of activity wristbands and behavior modification strategies on high school students' perceptions of autonomy support, satisfaction of basic psychological needs, motivation toward Physical Education and physical activity, intention to be physically active, and habitual physical activity levels.

Materials and methods

An initial sample of 353 high school students (final sample = 175; 45.7% females; mean age = 13.3 ± 1.2 years) from two public high schools were cluster-randomly assigned into the intermittent (IG, n = 100) and control (CG, n = 75) groups. The IG performed an intermittent teaching unit twice a week for eight weeks. Specifically, the last 15 min of each lesson were used. As the main strategy to promote the practice of regular physical activity, students wore an activity wristband the whole day during the intervention period. Additionally, other behavior modification strategies were also applied (e.g., educational counseling, physical activity goals or reminders). Regarding the CG, during the intervention period (i.e,, the eight weeks that took place the intermittent teaching unit) they also performed two Physical Education sessions, but without using activity wristbands or other behavior modification strategies. Before and after the intervention, as well as at the end of the follow-up period (six weeks), students' physical activity practice mediators and physical activity levels were measured by validated questionnaires.

Results

The Multilevel Linear Model results showed that the IG students statistically significantly improved cognitive and procedural autonomy support from pre- to post-intervention (p < 0.05). They also statistically significantly improved autonomy and relatedness basic psychological needs, and autonomous motivation toward physical activity scores from post-intervention to follow-up (p < 0.05). Moreover, the results showed that the IG students statistically significantly improved habitual physical activity scores from pre- to post-intervention, and from post-intervention to follow-up (p < 0.05).

Conclusion

The intermittent teaching unit based on the use of activity wristbands and other behavior modification strategies was effective for improving students' autonomy support and habitual physical activity levels, but not the rest of physical activity practice mediators.

Clinical trial registration

https://register.clinicaltrials.gov/, ID: NCT05949463.

Validity of activity wristbands for estimating daily physical activity in primary schoolchildren under free-living conditions: School-Fit study

Introduction

The use of activity wristbands to monitor and promote schoolchildren's physical activity (PA) is increasingly widespread. However, their validity has not been sufficiently studied, especially among primary schoolchildren. Consequently, the main purpose was to examine the validity of the daily steps and moderate-to-vigorous PA (MVPA) scores estimated by the activity wristbands Fitbit Ace 2, Garmin Vivofit Jr 2, and the Xiaomi Mi Band 5 in primary schoolchildren under free-living conditions.

Materials and methods

An initial sample of 67 schoolchildren (final sample = 62; 50% females), aged 9-12 years old (mean = 10.4 ± 1.0 years), participated in the present study. Each participant wore three activity wristbands (Fitbit Ace 2, Garmin Vivofit Jr 2, and Xiaomi Mi Band 5) on his/her non-dominant wrist and a research-grade accelerometer (ActiGraph wGT3X-BT) on his/her hip as the reference standard (number of steps and time in MVPA) during the waking time of one day.

Results

Results showed that the validity of the daily step scores estimated by the Garmin Vivofit Jr 2 and Xiaomi Mi Band 5 were good and acceptable (e.g., MAPE = 9.6/11.3%, and lower 95% IC of ICC = 0.87/0.73), respectively, as well as correctly classified schoolchildren as meeting or not meeting the daily 10,000/12,000-step-based recommendations, obtaining excellent/good and good/acceptable results (e.g., Garmin Vivofit Jr 2, k = 0.75/0.62; Xiaomi Mi Band 5, k = 0.73/0.53), respectively. However, the Fitbit Ace 2 did not show an acceptable validity (e.g., daily steps: MAPE = 21.1%, and lower 95% IC of ICC = 0.00; step-based recommendations: k = 0.48/0.36). None of the three activity wristbands showed an adequate validity for estimating daily MVPA (e.g., MAPE = 36.6-90.3%, and lower 95% IC of ICC = 0.00-0.41) and the validity for the MVPA-based recommendation tended to be considerably lower (e.g., k = -0.03-0.54).

Conclusions

The activity wristband Garmin Vivofit Jr 2 obtained the best validity for monitoring primary schoolchildren's daily steps, offering a feasible alternative to the research-grade accelerometers. Furthermore, this activity wristband could be used during PA promotion programs to provide accurate feedback to primary schoolchildren to ensure their accomplishment with the PA recommendations.

Validity of the Xiaomi Mi Band 2, 3, 4 and 5 Wristbands for Assessing Physical Activity in 12-to-18-Year-Old Adolescents under Unstructured Free-Living Conditions. Fit-Person Study

The purpose was to assess the validity of four generations of Xiaomi Mi Band wristbands for the assessment of step count and physical activity (PA) levels among adolescents aged 12-18 years under free-living conditions. One hundred adolescents were invited to participate in the present study. The final sample consisted of 62 high-school students (34 females), aged 12-18 years old (Mage = 14.1 ± 1.6 years), who wore an ActiGraph accelerometer on their hip (PA and step count reference measures) and four activity wristbands (Xiaomi Mi Band 2, 3, 4, and 5) on their non-dominant wrist during the waking time of one day. Results showed that the agreement between daily PA levels (i.e., slow, brisk, and slow-brisk pace walking, total PA and moderate-to-vigorous PA) measured by Xiaomi Mi Band wristbands and the accelerometer were poor (ICC, 95% CI = 0.06-0.78, 0.00-0.92; MAPE = 50.1-150.6%). However, agreement between daily step count measured by the accelerometer and the Xiaomi Mi Band wristbands were between acceptable (MAPE = 12.2-13.6%) to excellent (ICC, 95% CI = 0.94-0.95, 0.90-0.97). Furthermore, the Xiaomi Mi Band wristbands have a good to excellent validity for correctly classifying adolescents as meeting or not meeting the recommended 10,000 steps per day (P = 0.89-0.95, k = 0.71-0.87) and the recommended 60 minutes of moderate-to-vigorous PA per day (P = 0.89-0.94, k = 0.69-0.83). Furthermore, comparability between the four Xiaomi Mi Band generations were poor to excellent (ICC, 95% CI = 0.22-0.99, 0.00-1.00) for the daily PA levels outputs, although it was excellent (ICC, 95% CI = 0.99-1.00, 0.96-1.00; MAPE = 0.0-0.1%) for daily step count. Different models of Xiaomi Mi Band wristbands were comparable and presented good validity for measuring adolescents' step count, and they accurately classified adolescents as meeting or not meeting the PA recommendations under free-living conditions.

Development and Validation of Physical Activity-Specific Rumination Scale for Children Through UK Children's Voice

Many physical activity (PA) interventions implemented to tackle the child obesity epidemic have shown limited effectiveness, possibly due to a lack of consideration of potential stress that accompanies behavior adaptation and the automatic perseverative cognition that exacerbates the stress (namely rumination). Purpose: The main aim of this paper is to develop and validate the PA-specific Rumination Scale for Children (PARSC) that assesses children's tendencies to engage in repeated negative thoughts about PA (Study 2). Items in the scale were derived from qualitative information about factors that inherently demotivates PA participation (intrinsic barriers) through the lived experience of UK children (Study 1). Methods: For Study 1, pedometry PA data were collected from 143 children (aged 6-10 years). Twenty-one focus groups were formed based on participants' year group, sex and PA level. For PARSC validation (Study 2), 382 children completed the questionnaire twice. Self-report PA, device-based PA, and avoidant coping were also assessed. Results: Study 1-Four overarching themes identified as intrinsic barriers were lack of competence, fear of negative experiences, external constraints and lacking a sense of purpose. Altogether, 10 higher order and lower order themes were used to construct PARSC items. Study 2-From Rasch analysis, PARSC possessed sound internal validity, internal consistency, and test-retest reliability. Self-report PA and avoidant coping were predictive of PA-specific rumination, but not device-based PA. Conclusion: PARSC is a useful tool to identify children ruminative about PA for whom interventions can be designed, with the intrinsic barriers considered, to promote PA behavior adaptation.

The Challenge of Incomplete Data in Accelerometer Studies: Characteristics of Nonparticipation and Noncompliance in a Nationwide Sample of Adolescents and Young Adults in Germany

BACKGROUND

Incomplete data due to nonparticipation and noncompliance with the study protocol can bias the results of studies. We investigated how a nationwide accelerometer sample of adolescents and young adults is affected by such incomplete data.

METHODS

We analyzed cross-sectional data from 6465 participants (11-31 y old) who participated in a national health survey in Germany (KiGGS Wave 2; 2014-2017). The data included information about the participation in the measurement of physical activity using accelerometers, compliance with the wear-time protocol, and sociodemographic and health-related variables. Multivariable regression analyses were conducted to detect factors associated with incomplete data.

RESULTS

Of the total sample, 78.0% participated in the accelerometer part of the study, and 83.5% of the participants with data available complied with the wear-time protocol. In 11- to 17-year-olds, the likelihood of having incomplete accelerometer data was higher in boys, older adolescents, adolescents with a lower sociodemographic status, adolescents with overweight, adolescents not participating in organized sport, adolescents not speaking only German at home, current smokers, and adolescents having a higher soft drink consumption. In 18- to 31-year-olds, the likelihood of having incomplete accelerometer data was higher in men, adults with a lower educational level, adults not speaking only German at home, and adults who smoke.

CONCLUSIONS

Our results suggest that accelerometer samples are biased such that participants with more beneficial health behaviors provide complete accelerometer data more often. This knowledge should be used to design effective recruitment strategies and should be considered when interpreting results of accelerometer studies.

An Evaluation of Participant Perspectives and Wear-Time Compliance for a Wrist-Worn Versus Thigh-Worn Accelerometer in Cancer Survivors

BACKGROUND

Accelerometers are frequently used to measure free-living physical activity and sleep in cancer survivors. To obtain valid data, participants must adhere to wear-time guidelines; therefore, understanding survivor's preference may be critical when selecting an accelerometer. This study compared cancer survivors' reported discomfort and interference, and wear-time compliance between a wrist-worn accelerometer and a thigh-worn accelerometer.

METHODS

This was a secondary data analysis. Cancer survivors (N = 52, mean age = 51.8 [13.0], 82.3% female) wore the Actiwatch-2 (wrist) and the activPAL (thigh) for 7 days, 24 hours per day. On day 7, participants completed a questionnaire to evaluate each accelerometer using a 1 to 5 Likert scale and open-ended questions. The Kolmogorov-Smirnov test evaluated differences in discomfort and interference. Paired samples t test evaluated differences in wear-time compliance. Open-ended responses were analyzed using thematic analysis methods.

RESULTS

No differences were observed in discomfort, interference, or wear-time compliance (P = .08). Qualitative analysis resulted in 2 themes: discomfort and ease of use and interference and adverse reaction. Interferences were primarily reported with the Actiwatch-2, whereas discomfort and ease were primarily reported with the activPAL.

CONCLUSION

No significant differences were observed regarding discomfort, interference, and compliance. Results of this study can prepare researchers for common issues regarding accelerometer compliance, allowing researchers to offer resources to alleviate discomforts or interferences that may affect wear-time compliance.

High School Students' Accelerometer-Measured Physical Activity and Sedentary Behavior by Motivational Profiles Toward Physical Activity

Purpose: Based on a Self-Determination Theory with a person-centered approach, the purposes were: (1) to identify motivational profiles toward physical activity (PA) among high school students, and (2) to compare students' accelerometer-measured PA and sedentary behavior (SB) levels between the motivational profiles toward PA. Methods: The present study followed a cross-sectional design. A total of 394 high school students (173 females; final sample = 360 and 198 for the purposes 1 and 2, respectively) aged 12-16 years completed the study. Participants' PA and SB levels were objectively measured by ActiGraph GT3X+ accelerometers (right hip) during seven consecutive days. Later, motivation toward PA was measured by the Behavioral Regulation in Exercise Questionnaire. Results: Based on a two-stage cluster analysis approach, the results identified three clusters: (1) "Self-determined motivational profile toward PA" (65.3%); (2) "Non-self-determined motivational profile toward PA" (23.9%), and (3) "Controlled motivational profile toward PA" (10.8%). The results of the chi-square test showed that a statistically significantly higher percentage of males were represented in cluster 1 (p < .001). The results of the one-way analysis of variance showed that students from cluster 1 had statistically significantly lower levels of SB, and higher levels of light PA, moderate-to-vigorous PA and total PA than those from cluster 2 (p < .05; |d| = 0.40-0.61). Conclusions: In line with the Self-Determination Theory, the students within the self-determined motivational profile had lower SB and higher PA. This preliminary evidence could inform and guide future policy regarding students' PA promotion.

Feasibility of Measuring Screen Time, Activity, and Context Among Families With Preschoolers: Intensive Longitudinal Pilot Study

BACKGROUND

Digital media has made screen time more available across multiple contexts, but our understanding of the ways children and families use digital media has lagged behind the rapid adoption of this technology.

OBJECTIVE

This study evaluated the feasibility of an intensive longitudinal data collection protocol to objectively measure digital media use, physical activity, sleep, sedentary behavior, and socioemotional context among caregiver-child dyads. This paper also describes preliminary convergent validity of ecological momentary assessment (EMA) measures and preliminary agreement between caregiver self-reported phone use and phone use collected from passive mobile sensing.

METHODS

Caregivers and their preschool-aged child (3-5 years) were recruited to complete a 30-day assessment protocol. Within 30-days, caregivers completed 7 days of EMA to measure child behavior problems and caregiver stress. Caregivers and children wore an Axivity AX3 (Newcastle Upon Tyne) accelerometer to assess physical activity, sedentary behavior, and sleep. Phone use was assessed via passive mobile sensing; we used Chronicle for Android users and screenshots of iOS screen time metrics for iOS users. Participants were invited to complete a second 14-day protocol approximately 3-12 months after their first assessment. We used Pearson correlations to examine preliminary convergent validity between validated questionnaire measures of caregiver psychological functioning, child behavior, and EMA items. Root mean square errors were computed to examine the preliminary agreement between caregiver self-reported phone use and objective phone use.

RESULTS

Of 110 consenting participants, 105 completed all protocols (105/110, 95.5% retention rate). Compliance was defined a priori as completing ≥70%-75% of each protocol task. There were high compliance rates for passive mobile sensing for both Android (38/40, 95%) and iOS (64/65, 98%). EMA compliance was high (105/105, 100%), but fewer caregivers and children were compliant with accelerometry (62/99, 63% and 40/100, 40%, respectively). Average daily phone use was 383.4 (SD 157.0) minutes for Android users and 354.7 (SD 137.6) minutes for iOS users. There was poor agreement between objective and caregiver self-reported phone use; root mean square errors were 157.1 and 81.4 for Android and iOS users, respectively. Among families who completed the first assessment, 91 re-enrolled to complete the protocol a second time, approximately 7 months later (91/105, 86.7% retention rate).

CONCLUSIONS

It is feasible to collect intensive longitudinal data on objective digital media use simultaneously with accelerometry and EMA from an economically and racially diverse sample of families with preschool-aged children. The high compliance and retention of the study sample are encouraging signs that these methods of intensive longitudinal data collection can be completed in a longitudinal cohort study. The lack of agreement between self-reported and objectively measured mobile phone use highlights the need for additional research using objective methods to measure digital media use.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-36240.

Accuracy of gait and posture classification using movement sensors in individuals with mobility impairment after stroke

Background: Stroke leads to motor impairment which reduces physical activity, negatively affects social participation, and increases the risk of secondary cardiovascular events. Continuous monitoring of physical activity with motion sensors is promising to allow the prescription of tailored treatments in a timely manner. Accurate classification of gait activities and body posture is necessary to extract actionable information for outcome measures from unstructured motion data. We here develop and validate a solution for various sensor configurations specifically for a stroke population.

Methods: Video and movement sensor data (locations: wrists, ankles, and chest) were collected from fourteen stroke survivors with motor impairment who performed real-life activities in their home environment. Video data were labeled for five classes of gait and body postures and three classes of transitions that served as ground truth. We trained support vector machine (SVM), logistic regression (LR), and k-nearest neighbor (kNN) models to identify gait bouts only or gait and posture. Model performance was assessed by the nested leave-one-subject-out protocol and compared across five different sensor placement configurations.

Results: Our method achieved very good performance when predicting real-life gait versus non-gait (Gait classification) with an accuracy between 85% and 93% across sensor configurations, using SVM and LR modeling. On the much more challenging task of discriminating between the body postures lying, sitting, and standing as well as walking, and stair ascent/descent (Gait and postures classification), our method achieves accuracies between 80% and 86% with at least one ankle and wrist sensor attached unilaterally. The Gait and postures classification performance between SVM and LR was equivalent but superior to kNN.

Conclusion: This work presents a comparison of performance when classifying Gait and body postures in post-stroke individuals with different sensor configurations, which provide options for subsequent outcome evaluation. We achieved accurate classification of gait and postures performed in a real-life setting by individuals with a wide range of motor impairments due to stroke. This validated classifier will hopefully prove a useful resource to researchers and clinicians in the increasingly important field of digital health in the form of remote movement monitoring using motion sensors.

The GRANDPACT Project: The Development and Evaluation of an Intergenerational Program for Grandchildren and Their Grandparents to Stimulate Physical Activity and Cognitive Function Using Co-Creation

In recent years, increased attention has been devoted to intergenerational physical activity (PA) programs because they may have several benefits for both children and older adults (e.g., the reduction of ageism). An intergenerational PA program focusing on grandchildren and grandparents in a 'standard' family setting that combines PA and cognitive function is innovative and may hold potential for promoting PA and improving cognitive functioning in both grandchildren and grandparents. The aim of this study is to describe the protocol of the GRANDPACT (GRANDparents and GRANDchildren improve their Physical Activity and Cognitive functions using co-creaTion) Project, focusing on the development of an intergenerational, cognitively enriched, movement program for grandchildren and grandparents using the theoretical framework of the "Behaviour Change Wheel" in combination with a co-creation approach. Two co-creation trajectories will be organized to develop the program, followed by a pilot study to refine the program and an RCT with a pre-test (at baseline), a post-test (after 24 weeks), and a follow-up (after 36 weeks) to measure the outcomes of co-PA, cognitive functions, psychosocial well-being, and the quality of the family relationship ingrandchildren and grandparents. The outcomes will be measured using accelerometry for PA, the Cambridge Neuropsychological Test Automated Battery (CANTAB) for cognitive functions, and questionnaires for the psychological well-being and quality of the family relationship. Co-development with end-users and stakeholders during both co-creation trajectories is expected to result in an effective, attractive, and feasible program. Co-PA is expected to improve PA, cognitive functioning, psychosocial well-being, and the quality of the family relationships between grandchildren and grandparents.

Peer-led physical activity intervention for girls aged 13 to 14 years: PLAN-A cluster RCT

Background

Increasing physical activity among girls is a public health priority. Peers play a central role in influencing adolescent behaviour. Peer-led interventions may increase physical activity in adolescent girls, and a feasibility trial had shown that PLAN-A (Peer-led physical Activity iNtervention for Adolescent girls) had evidence of promise to increase physical activity in adolescent girls.

Objective

The objective was to test whether or not PLAN-A can increase adolescent girls’ physical activity, relative to usual practice, and be cost-effective.

Design

This was a two-arm, cluster-randomised controlled trial, including an economic evaluation and a process evaluation.

Participants

State-funded secondary schools in the UK with girls in Year 9 (aged 13–14 years) participated in the trial. All Year 9 girls in participating schools were eligible.

Randomisation

Schools were the unit of allocation. They were randomised by an independent statistician, who was blinded to school identities, to the control or intervention arm, stratified by region and the England Index of Multiple Deprivation score.

Intervention

The intervention comprised peer nomination (i.e. identification of influential girls), train the trainers (i.e. training the instructors who delivered the intervention), peer supporter training (i.e. training the peer-nominated girls in techniques and strategies underpinned by motivational theory to support peer physical activity increases) and a 10-week diffusion period.

Outcomes

The primary outcome was accelerometer-assessed mean weekday minutes of moderate to vigorous physical activity among Year 9 girls. The follow-up measures were conducted 5–6 months after the 10-week intervention, when the girls were in Year 10 (which was also 12 months after the baseline measures). Analysis used a multivariable, mixed-effects, linear regression model on an intention-to-treat basis. Secondary outcomes included weekend moderate to vigorous physical activity, and weekday and weekend sedentary time. Intervention delivery costs were calculated for the economic evaluation.

Results

A total of 33 schools were approached; 20 schools and 1558 pupils consented. Pupils in the intervention arm had higher Index of Multiple Deprivation scores than pupils in the control arm. The numbers randomised were as follows: 10 schools (n = 758 pupils) were randomised to the intervention arm and 10 schools (n = 800 pupils) were randomised to the control arm. For analysis, a total of 1219 pupils provided valid weekday accelerometer data at both time points (intervention, n = 602; control, n = 617). The mean weekday moderate to vigorous physical activity was similar between groups at follow-up. The central estimate of time spent engaging in moderate to vigorous physical activity was 2.84 minutes lower in the intervention arm than in the control arm, after adjustment for baseline mean weekday moderate to vigorous physical activity, the number of valid days of data and the stratification variables; however, this difference was not statistically significant (95% confidence interval –5.94 to 0.25; p = 0.071). There were no between-arm differences in the secondary outcomes. The intervention costs ranged from £20.85 to £48.86 per pupil, with an average cost of £31.16.

Harms

None.

Limitations

The trial was limited to south-west England.

Conclusions

There was no evidence that PLAN-A increased physical activity in Year 9 girls compared with usual practice and, consequently, it was not cost-effective.

Future work

Future work should evaluate the utility of whole-school approaches to promote physical activity in schools.

Trial registration

This trial is registered as ISRCTN14539759.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 10, No. 6. See the NIHR Journals Library website for further project information. This trial was designed and delivered in collaboration with the Bristol Randomised Trials Collaboration (BRTC), a United Kingdom Clinical Research Commission (UKCRC)-registered Clinical Trials Unit that, as part of the Bristol Trials Centre, is in receipt of NIHR Clinical Trials Unit support funding. The sponsor of this trial was University of Bristol, Research and Enterprise Development www.bristol.ac.uk/red/. The costs of delivering the intervention were funded by Sport England.

Effect of incentive amount on US adolescents' participation in an accelerometer data collection component of a national survey

Behavioral research increasingly uses accelerometers to provide objective estimates of physical activity. This study extends research on methods for collecting accelerometer data among youth by examining whether the amount of a monetary incentive affects enrollment and compliance in a mail-based accelerometer study of adolescents. We invited a subset of adolescents in a national web-based study to wear an accelerometer for seven days and return it by mail; participants received either $20 or $40 for participating. Enrollment did not significantly differ by incentive amount. However, adolescents receiving the $40 incentive had significantly higher compliance (accelerometer wear and return). This difference was largely consistent across demographic subgroups. Those in the $40 group also wore the accelerometer for more time than the $20 group on the first two days of the study. Compared to $20, a $40 incentive may promote youth completion of mail-based accelerometer studies.

A school-based, peer-led programme to increase physical activity among 13- to 14-year-old adolescents: the GoActive cluster RCT

Background

Adolescent physical activity levels are low and are associated with rising disease risk and social disadvantage. The Get Others Active (GoActive) intervention was co-designed with adolescents and teachers to increase physical activity in adolescents.

Objective

To assess the effectiveness and cost-effectiveness of the school-based GoActive programme in increasing adolescents’ moderate-to-vigorous physical activity.

Design

A cluster randomised controlled trial with an embedded mixed-methods process evaluation.

Setting

Non-fee-paying schools in Cambridgeshire and Essex, UK (n = 16). Schools were computer randomised and stratified by socioeconomic position and county.

Participants

A total of 2862 Year 9 students (aged 13–14 years; 84% of eligible students).

Intervention

The iteratively developed feasibility-tested refined 12-week intervention trained older adolescents (mentors) and in-class peer leaders to encourage classes to undertake two new weekly activities. Mentors met with classes weekly. Students and classes gained points and rewards for activity in and out of school.

Main outcome measures

The primary outcome was average daily minutes of accelerometer-assessed moderate-to-vigorous physical activity at 10 months post intervention. Secondary outcomes included accelerometer-assessed activity during school, after school and at weekends; self-reported physical activity and psychosocial outcomes; cost-effectiveness; well-being and a mixed-methods process evaluation. Measurement staff were blinded to allocation.

Results

Of 2862 recruited participants, 2167 (76%) attended 10-month follow-up measurements and we analysed the primary outcome for 1874 (65.5%) participants. At 10 months, there was a mean decrease in moderate-to-vigorous physical activity of 8.3 (standard deviation 19.3) minutes in control participants and 10.4 (standard deviation 22.7) minutes in intervention participants (baseline-adjusted difference –1.91 minutes, 95% confidence interval –5.53 to 1.70 minutes; p = 0.316). The programme cost £13 per student compared with control. Therefore, it was not cost-effective. Non-significant indications of differential impacts suggested detrimental effects among boys (boys –3.44, 95% confidence interval –7.42 to 0.54; girls –0.20, 95% confidence interval –3.56 to 3.16), but favoured adolescents from lower socioeconomic backgrounds (medium/low 4.25, 95% confidence interval –0.66 to 9.16; high –2.72, 95% confidence interval –6.33 to 0.89). Mediation analysis did not support the use of any included intervention components to increase physical activity. Some may have potential for improving well-being. Students, teachers and mentors mostly reported enjoying the GoActive intervention (56%, 87% and 50%, respectively), but struggled to conceptualise their roles. Facilitators of implementation included school support, embedding a routine, and mentor and tutor support. Challenges to implementation included having limited school space for activities, time, and uncertainty of teacher and mentor roles.

Limitations

Retention on the primary outcome at 10-month follow-up was low (65.5%), but we achieved our intended sample size, with retention comparable to similar trials.

Conclusions

A rigorously developed school-based intervention (i.e. GoActive) was not effective in countering the age-related decline in adolescent physical activity. Overall, this mixed-methods evaluation provides transferable insights for future intervention development, implementation and evaluation.

Future work

Interdisciplinary research is required to understand educational setting-specific implementation challenges. School leaders and authorities should be realistic about expectations of the effect of school-based physical activity promotion strategies implemented at scale.

Trial registration

Current Controlled Trials ISRCTN31583496.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 9, No. 6. See the NIHR Journals Library website for further project information. This work was additionally supported by the Medical Research Council (London, UK) (Unit Programme number MC_UU_12015/7) and undertaken under the auspices of the Centre for Diet and Activity Research (Cambridge, UK), a UK Clinical Research Collaboration Public Health Research Centre of Excellence. Funding from the British Heart Foundation (London, UK), Cancer Research UK (London, UK), Economic and Social Research Council (Swindon, UK), Medical Research Council, the National Institute for Health Research (Southampton, UK) and the Wellcome Trust (London, UK), under the auspices of the UK Clinical Research Collaboration, is gratefully acknowledged (087636/Z/08/Z; ES/G007462/1; MR/K023187/1). GoActive facilitator costs were borne by Essex and Cambridgeshire County Councils.

Physical activity and fitness: The feasibility and preliminary effectiveness of wearable activity tracker technology incorporating altruistic motivation in youth

PURPOSE

The purpose of this study was to examine the feasibility and preliminary effectiveness of using wearable activity tracker technology, integrated with altruistic motivation in children to increase physical activity (PA), fitness, and prosocial behavior.

DESIGN AND METHODS

A quasiexperimental design was employed in two 4th grade classrooms in a rural southern state. The intervention was a wearable PA tracker and a web-based curriculum with activities to earn power points redeemable to provide life-saving food to undernourished kids internationally. Seventeen children in the intervention group participated in the 10-week PA program and 18 children were in the wait listed control group. Three measures were assessed in both groups at baseline and postintervention: (a) PA measured with accelerometers, (b) fitness levels measured with shuttle run, and (c) prosocial behavior measured with Strengths and Difficulties questionnaire.

RESULTS

Of the 35 children enrolled, the majority were nine years old (n = 28), black (n = 31) and female (n = 23). An overall enrollment rate of 88%, attrition rate of 9%, and an accelerometer noncompliance rate of 25% was determined to assess feasibility. There was no statistical significance between the control and intervention group outcome variables. The average minutes of PA in the control group decreased 8 min from baseline to postintervention (p = .05). In the intervention group, PA decreased by 10 min from baseline to postintervention (p = .12). In both the control and intervention groups, prosocial behavior scores decreased (p = .09 control; p = .62 intervention). The fitness scores, VO₂ max, did not significantly change (intervention p = .21; control p = .35).

PRACTICE IMPLICATIONS

Developing effective interventions that foster PA and dissuade sedentary behaviors are essential to enhancing PA and fitness levels. The recruitment, retention, and accelerometer wear adherence suggest this setting, with this population is feasible. The intervention is deliverable, however, the potential of wearable activity trackers and the effect of prosocial behavior that benefits others in increasing PA and improving cardiorespiratory fitness, should be further researched by building on the successful elements of this study.

Reducing cardiovascular disease risk among families with familial hypercholesterolaemia by improving diet and physical activity: a randomised controlled feasibility trial

OBJECTIVE

Familial hypercholesterolaemia (FH) elevates low-density lipoprotein cholesterol (LDL-C) and increases cardiovascular disease (CVD) risk. This study aimed to provide evidence for the feasibility of conducting a randomised controlled trial to evaluate the efficacy of an intervention designed to improve diet and physical activity in families with FH.

DESIGN

A parallel, randomised, waitlist-controlled, feasibility pilot trial.

SETTING

Three outpatient lipid clinics in the UK.

PARTICIPANTS

Families that comprised children (aged 10-18 years) and their parent with genetically diagnosed FH.

INTERVENTION

Families were randomised to either 12-week usual care or intervention. The behavioural change intervention aimed to improve dietary, physical activity and sedentary behaviours. It was delivered to families by dietitians initially via a single face-to-face session and then by four telephone or email follow-up sessions.

OUTCOME MEASURES

Feasibility was assessed via measures related to recruitment, retention and intervention fidelity. Postintervention qualitative interviews were conducted to explore intervention acceptability. Behavioural (dietary intake, physical activity and sedentary time) and clinical (blood pressure, body composition and blood lipids) outcomes were collected at baseline and endpoint assessments to evaluate the intervention's potential benefit.

RESULTS

Twenty-one families (38% of those approached) were recruited which comprised 22 children and 17 adults with FH, and 97% of families completed the study. The intervention was implemented with high fidelity and the qualitative data revealed it was well accepted. Between-group differences at the endpoint assessment were indicative of the intervention's potential for improving diet in children and adults. Evidence for potential benefits on physical activity and sedentary behaviours was less apparent. However, the intervention was associated with improvements in several CVD risk factors including LDL-C, with a within-group mean decrease of 8% (children) and 10% (adults).

CONCLUSIONS

The study's recruitment, retention, acceptability and potential efficacy support the development of a definitive trial, subject to identified refinements.

TRIAL REGISTRATION NUMBER

ISRCTN24880714.

Improving remote lifestyle intervention studies in children: Participant and caregiver feedback of the smart heart study

OBJECTIVES

We sought to describe and analyze the quantitative and qualitative feedback obtained from participants and their caregivers of the Smart Heart study, a successful 12-month lifestyle intervention for children with overweight or obesity and congenital heart disease that provided remote lifestyle counseling, to improve future lifestyle interventions in children.

METHODS

Thirty-six participants and caregivers were polled using a standard program evaluation questionnaire at the end of the intervention. Feedback was compiled into themes, and facilitators and barriers to program success were identified.

RESULTS

There was a high level of satisfaction with the intervention and staff interactions as well as a low perceived burden of participation. There were also specific concerns, including mixed impressions regarding technology usage and a less impressive indication of actual impactful behavior change.

CONCLUSIONS

The study identified five themes, and corresponding facilitators and barriers to participant compliance, from the Smart Heart intervention feedback and offered suggestions for improving future lifestyle behavioral intervention study designs in children.

PRACTICE IMPLICATIONS

Remote smartphone counseling is effective and efficient. It is recommended that the counseling messages are specific, the counseling schedule is patient-centric, patient burden is limited, methods with immediate patient feedback are used and family is included when feasible.

Effectiveness and cost-effectiveness of the GoActive intervention to increase physical activity among UK adolescents: A cluster randomised controlled trial

BACKGROUND

Less than 20% of adolescents globally meet recommended levels of physical activity, and not meeting these recommended levels is associated with social disadvantage and rising disease risk. The determinants of physical activity in adolescents are multilevel and poorly understood, but the school's social environment likely plays an important role. We conducted a cluster randomised controlled trial to assess the effectiveness of a school-based programme (GoActive) to increase moderate-to-vigorous physical activity (MVPA) among adolescents.

METHODS AND FINDINGS

Non-fee-paying, co-educational schools including Year 9 students in the UK counties of Cambridgeshire and Essex were eligible for inclusion. Within participating schools (n = 16), all Year 9 students were eligible and invited to participate. Participants were 2,862 13- to 14-year-olds (84% of eligible students). After baseline assessment, schools were computer-randomised, stratified by school-level pupil premium funding (below/above county-specific median) and county (control: 8 schools, 1,319 participants, mean [SD] participants per school n = 165 [62]; intervention: 8 schools, 1,543 participants, n = 193 [43]). Measurement staff were blinded to allocation. The iteratively developed, feasibility-tested 12-week intervention, aligned with self-determination theory, trained older adolescent mentors and in-class peer-leaders to encourage classes to conduct 2 new weekly activities. Students and classes gained points and rewards for engaging in any activity in or out of school. The primary outcome was average daily minutes of accelerometer-assessed MVPA at 10-month follow-up; a mixed-methods process evaluation evaluated implementation. Of 2,862 recruited participants (52.1% male), 2,167 (76%) attended 10-month follow-up measurements; we analysed the primary outcome for 1,874 participants (65.5%). At 10 months, there was a mean (SD) decrease in MVPA of 8.3 (19.3) minutes in the control group and 10.4 (22.7) minutes in the intervention group (baseline-adjusted difference [95% confidence interval] -1.91 minutes [-5.53 to 1.70], p = 0.316). The programme cost £13 per student compared with control; it was not cost-effective. Overall, 62.9% of students and 87.3% of mentors reported that GoActive was fun. Teachers and mentors commented that their roles in programme delivery were unclear. Implementation fidelity was low. The main methodological limitation of this study was the relatively affluent and ethnically homogeneous sample.

CONCLUSIONS

In this study, we observed that a rigorously developed school-based intervention was no more effective than standard school practice at preventing declines in adolescent physical activity. Interdisciplinary research is required to understand educational-setting-specific implementation challenges. School leaders and authorities should be realistic about expectations of the effect of school-based physical activity promotion strategies implemented at scale.

TRIAL REGISTRATION

ISRCTN Registry ISRCTN31583496.

Physical activity across the curriculum (PAAC3): Testing the application of technology delivered classroom physical activity breaks

Only 43% of children in the U.S., ages 6-11 yrs., meet current physical activity (PA) guidelines. To satisfy the MVPA requirement, schools have begun incorporating MVPA in the form of activity breaks or MVPA academic lessons. We completed two, 3 academic-yr. cluster randomized trials (DK61489, DK85317) called "Physical Activity Across the Curriculum" (PAAC) which involved increasing MVPA in the classroom. Across 3-yrs. teachers in PAAC schools delivered ~60 min/wk. (12 min/day) of MVPA. Although short of our MVPA goal (20 min/d), the PAAC approach substantially increased in-school MVPA. Teacher reluctance to devote additional time to develop and integrate PA lessons into their curriculum was the overwhelming barrier to meeting the MVPA goal. Therefore, to reduce barriers to delivery of classroom PA we developed a 3-academic yr. cluster randomized trial (2 yrs. active intervention, 1 yr. follow-up) to compare the effectiveness and sustainability of technology delivered (PAAC-R) and classroom teacher delivered (PAAC-T) activity breaks for increasing classroom MVPA in elementary school students in grades 2 and 3 at baseline who will progress to grades 4-5. NCT registration: NCT03493139.

Pathways to Increasing Adolescent Physical Activity and Wellbeing: A Mediation Analysis of Intervention Components Designed Using a Participatory Approach

We assessed which intervention components were associated with change in moderate-to-vigorous physical activity (MVPA) and wellbeing through proposed psychosocial mediators. Eight schools (n = 1319; 13–14 years) ran GoActive, where older mentors and in-class-peer-leaders encouraged classes to conduct two new activities/week; students gained points and rewards for activity. We assessed exposures: participant-perceived engagement with components (post-intervention): older mentorship, peer leadership, class sessions, competition, rewards, points entered online; potential mediators (change from baseline): social support, self-efficacy, group cohesion, friendship quality, self-esteem; and outcomes (change from baseline): accelerometer-assessed MVPA (min/day), wellbeing (Warwick-Edinburgh). Mediation was assessed using linear regression models stratified by gender (adjusted for age, ethnicity, language, school, BMI z-score, baseline values), assessing associations between (1) exposures and mediators, (2) exposures and outcomes (without mediators) and (3) exposure and mediator with outcome using bootstrap resampling. No evidence was found to support the use of these components to increase physical activity. Among boys, higher perceived teacher and mentor support were associated with improved wellbeing via various mediators. Among girls, higher perceived mentor support and perception of competition and rewards were positively associated with wellbeing via self-efficacy, self-esteem and social support. If implemented well, mentorship could increase wellbeing among adolescents. Teacher support and class-based activity sessions may be important for boys’ wellbeing, whereas rewards and competition warrant consideration among girls.

A feasibility cluster randomised controlled trial of a preschool obesity prevention intervention: ToyBox-Scotland

BACKGROUND

High levels of childhood obesity have been observed globally over the last three decades. Preschools are promising settings to implement obesity prevention interventions in the early years. The aim of this study was to test the feasibility of a cluster randomised controlled trial of the ToyBox-Scotland preschool obesity prevention intervention.

METHODS

Six preschools in predominantly deprived areas of Glasgow, UK, were randomised to either the ToyBox intervention (n = 3) or usual curriculum control group (n = 3). The intervention ran for 18 weeks from March-June 2018, and consisted of practitioner-led physical activity and sedentary behaviour sessions in preschools, with an additional interactive home component. Primary outcome measures were intervention fidelity, recruitment rates, attrition rates, and compliance with trial procedures. Secondary outcomes were body mass index (BMI) z-score, bioelectrical impedance analysis (BIA), objectively measured physical activity and sedentary time via activPAL accelerometer, and parent-reported home eating, snacking, and water consumption.

RESULTS

The preschool component of the intervention was implemented with high fidelity (64%), while the home component was implemented with low fidelity (41%). A cluster-level recruitment rate of 10% was achieved, and the individual-level recruitment rate was 18% (42/233 children, mean age 4.4 years; 17 girls). The attrition rate was 14%, and compliance rates varied considerably by the outcome. Compliance was highest for BMI (86%), while 19% of the sample returned valid accelerometer data for both baseline and follow-up and the parental questionnaire response rate was 23%. Both intervention and control groups showed small increases in BMI z-scores at follow-up of 0.02 and 0.06, respectively. Both groups had small decreases in physical activity and increases in sedentary time at follow-up.

CONCLUSIONS

Before progression to an effectiveness trial, additional procedures should be considered to improve recruitment rates, compliance with outcome measures, and implementation of the home-based component of the ToyBox-Scotland intervention.

TRIAL REGISTRATION

ISRCTN12831555.

Compliance of Adolescent Girls to Repeated Deployments of Wrist-Worn Accelerometers

PURPOSE

This study aimed to determine the cross-sectional and cumulative compliance of adolescent girls to accelerometer wear at three deployment points and to identify variables associated with compliance.

METHODS

Girls from 20 secondary schools were recruited: 10 schools were participating in the "Girls Active" intervention and 10 were control schools. Physical activity was measured using the GENEActiv accelerometer worn on the nondominant wrist 24 h·d for up to 7 d at baseline, 7 months, and 14 months. Demographic and anthropometric characteristics were recorded.

RESULTS

Seven valid days (≥16 h) of accelerometer wear was obtained from 83%, 77%, and 68% of girls at baseline (n = 1734), 7 months (n = 1381), and 14 months (n = 1326), respectively. Sixty-eight percent provided 7 valid days for both baseline and 7 months, 59% for baseline and 14 months, and 52% for all three deployment points. Estimates of physical activity level from 3 d of measurement could be considered equivalent to a 7-d measure (i.e., they fell within a ±5% equivalence zone). Cross sectionally, 3 valid days was obtained from at least 91% of girls; cumulatively, this was obtained from ≥88% of girls across any two deployment points and 84% of girls across all three deployment points. When controlling for clustering at school level and other potential predictors, physical activity level, being South Asian, being in the intervention group, and prior compliance were positively associated with monitor wear.

CONCLUSIONS

Compliance reduced across deployment points, with the reduction increasing as the deployment points got further apart. High prior compliance and high physical activity level were associated with the most additional wear time.

A school-based intervention (‘Girls Active’) to increase physical activity levels among 11- to 14-year-old girls: cluster RCT

Background

Physical activity (PA) levels among adolescent girls in the UK are low. ‘Girls Active’, developed by the Youth Sport Trust (YST), has been designed to increase girls’ PA levels.

Objective

To understand the effectiveness and cost-effectiveness of the Girls Active programme.

Design

A two-arm cluster randomised controlled trial.

Setting

State secondary schools in the Midlands, UK.

Participants

Girls aged between 11 and 14 years.

Intervention

Girls Active involves teachers reviewing PA, sport and physical education provision, culture and practices in their school; attending training; creating action plans; and effectively working with girls as peer leaders to influence decision-making and to promote PA to their peers. Support from a hub school and the YST is offered.

Main outcome measures

The change in objectively measured moderate to vigorous intensity PA (MVPA) levels at 14 months. Secondary outcomes included changes in overall PA level (mean acceleration), light PA levels, sedentary time, body composition and psychosocial outcomes. Cost-effectiveness and process evaluation (qualitative and quantitative) data were collected.

Results

Twenty schools and 1752 pupils were recruited; 1211 participants provided complete primary outcome data at 14 months. No difference was found in mean MVPA level between groups at 14 months [1.7 minutes/day, 95% confidence interval (CI) –0.8 to 4.3 minutes/day], but there was a small difference in mean MVPA level at 7 months (2.4 minutes/day, 95% CI 0.1 to 4.7 minutes/day). Significant differences between groups were found at 7 months, but not at 14 months, in some of the objective secondary outcomes: overall PA level represented by average acceleration (1.39 mg, 95% CI 0.1 to 2.2 mg), after-school sedentary time (–4.7 minutes/day, 95% CI –8.9 to –0.6 minutes/day), overall light PA level (5.7 minutes/day, 95% CI 1.0 to 10.5 minutes/day) and light PA level on school days (4.5 minutes/day, 95% CI 0.25 to 8.75 minutes/day). Minor, yet statistically significant, differences in psychosocial measures at 7 months were found in favour of control schools. Significant differences in self-esteem and identified motivation in favour of intervention schools were found at 7 and 14 months, respectively. Subgroup analyses showed a significant effect of the intervention for those schools with higher numbers of pupils at 14 months. Girls Active was well received by teachers, and they reported that implemented strategies and activities were having a positive impact in schools. Barriers to implementation progress included lack of time, competing priorities and the programme flexibility. Implementation costs ranged from £2054 (£23/pupil) to £8545 (£95/pupil) per school. No differences were found between groups for health-related quality-of-life scores or frequencies, or for costs associated with general practitioner, school nurse and school counsellor use.

Conclusions

Girls Active may not have had an effect on the random 90 girls per school included in the evaluation. Although we included a diverse sample of schools, the results may not be generalisable to all schools. Girls Active was viewed positively but teachers did not implement as many aspects of the programme as they wanted. The intervention was unlikely to have a wide impact and did not have an impact on MVPA level at 14 months. Capitalising on the opportunities of a flexible programme like this, while also learning from the stated barriers to and challenges of long-term implementation that teachers face, is a priority for research and practice.

Trial registration

Current Controlled Trials ISRCTN10688342.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full inPublic Health Research; Vol. 7, No. 5. See the NIHR Journals Library website for further project information. The YST funded the intervention. This study was undertaken in collaboration with the Leicester Clinical Trials Unit, a UK Clinical Research Collaboration-registered clinical trials unit in receipt of NIHR Clinical Trials Unit support funding. Neither the YST nor the NIHR Clinical Trials Unit had any involvement in the Trial Steering Committee, data analysis, data interpretation, data collection or writing of the report. The University of Leicester authors are supported by the NIHR Leicester–Loughborough Biomedical Research Unit (2012–17), the NIHR Leicester Biomedical Research Centre (2017–22) and the Collaboration for Leadership in Applied Health Research and Care East Midlands. These funders had no involvement in the Trial Steering Committee, the data analysis, data interpretation, data collection or writing of the report.

Accelerometer-Derived Activity Phenotypes in Young Adults: a Latent Class Analysis

PURPOSE

To identify "activity phenotypes" from accelerometer-derived activity characteristics among young adults.

METHODS

Participants were young adults (n = 628, mean age, 22.1, SD 0.6) in the Raine Study in Western Australia. Sex-specific latent class analyses identified sub-groups using eight indicators derived from 7-day hip-worn Actigraph GT3X+ accelerometers: daily steps, total daily moderate-to-vigorous physical activity (MVPA), MVPA variation, MVPA intensity, MVPA bout duration, sedentary-to-light ratio, sedentary-to-light ratio variation, and sedentary bout duration.

RESULTS

Five activity phenotypes were identified for women (n = 324) and men (n = 304). Activity phenotype 1 for both women (35%) and men (30%) represented average activity characteristics. Phenotype 2 for women (17%) and men (16%) was characterized by below average total activity and MVPA (10.6 and 16.7 min of MVPA/day, women and men respectively). Phenotype 3 for women (15%) and men (23%) was characterized by below average total physical activity, average MVPA (32.6 and 36.5 min/day), high sedentary-light ratio and long sedentary bouts. Phenotype 4 differed between women (29%) and men (18%) but both had low sedentary-to-light ratios and shorter sedentary bouts. Finally, phenotype 5 in both women (4%) and men (12%) was characterized by extreme MVPA metrics (81.3 and 96.1 min/day).

CONCLUSIONS

Five activity phenotypes were identified for each gender in this population of young adults which can help design targeted interventions to enhance or modulate activity phenotypes.

Feasibility of Using a Commercial Fitness Tracker as an Adjunct to Family-Based Weight Management Treatment: Pilot Randomized Trial

Background

Fitness trackers can engage users through automated self-monitoring of physical activity. Studies evaluating the utility of fitness trackers are limited among adolescents, who are often difficult to engage in weight management treatment and are heavy technology users.

Objective

We conducted a pilot randomized trial to describe the impact of providing adolescents and caregivers with fitness trackers as an adjunct to treatment in a tertiary care weight management clinic on adolescent fitness tracker satisfaction, fitness tracker utilization patterns, and physical activity levels.

Methods

Adolescents were randomized to 1 of 2 groups (adolescent or dyad) at their initial weight management clinic visit. Adolescents received a fitness tracker and counseling around activity data in addition to standard treatment. A caregiver of adolescents in the dyad group also received a fitness tracker. Satisfaction with the fitness tracker, fitness tracker utilization patterns, and physical activity patterns were evaluated over 3 months.

Results

A total of 88 adolescents were enrolled, with 69% (61/88) being female, 36% (32/88) black, 23% (20/88) Hispanic, and 63% (55/88) with severe obesity. Most adolescents reported that the fitness tracker was helping them meet their healthy lifestyle goals (69%) and be more motivated to achieve a healthy weight (66%). Despite this, 68% discontinued use of the fitness tracker by the end of the study. There were no significant differences between the adolescent and the dyad group in outcomes, but adolescents in the dyad group were 12.2 times more likely to discontinue using their fitness tracker if their caregiver also discontinued use of their fitness tracker (95% CI 2.4-61.6). Compared with adolescents who discontinued use of the fitness tracker during the study, adolescents who continued to use the fitness tracker recorded a higher number of daily steps in months 2 and 3 of the study (mean 5760 vs 4148 in month 2, P=.005, and mean 5942 vs 3487 in month 3, P=.002).

Conclusions

Despite high levels of satisfaction with the fitness trackers, fitness tracker discontinuation rates were high, especially among adolescents whose caregivers also discontinued use of their fitness tracker. More studies are needed to determine how to sustain the use of fitness trackers among adolescents with obesity and engage caregivers in adolescent weight management interventions.

The effectiveness of eHealth interventions on physical activity and measures of obesity among working-age women: a systematic review and meta-analysis

Physical inactivity and obesity are modifiable risk factors for cardiovascular disease, particularly in women. eHealth interventions may increase physical activity and improve obesity-related outcomes among women. The objective of this study was to review the evidence of the effectiveness of eHealth interventions to increase moderate-to-vigorous physical activity among working-age women. The secondary objective was to examine their effectiveness on improving obesity-related outcomes. A comprehensive search strategy was developed for eight electronic databases; through July 2016. All studies consisting of >80% women of working-age (18-65 years) in high income countries were included. Multiple unblinded reviewers determined study eligibility and extracted data. Risk of bias was evaluated using the Cochrane Risk of Bias Tool and data quality using the Grading of Recommendations Assessment, Development and Evaluation approach. Data were pooled using a random-effects model. Sixty studies were included in the review of which 20 were in the meta-analysis. The meta-analysis demonstrated eHealth interventions improved moderate-to-vigorous physical activity (standard mean difference = 1.13, 95% confidence interval: 0.58, 1.68, P < 0.0001); an increase of ~25 min week^-1 . No changes were observed in obesity-related outcomes; waist circumference (P = 0.06), body mass (P = 0.05) and body mass index (P = 0.35). eHealth interventions are effective at increasing min week^-1 of moderate-to-vigorous physical activity among working-age women from high income countries.

Wear-Time Compliance with a Dual-Accelerometer System for Capturing 24-h Behavioural Profiles in Children and Adults

To advance the field of time-use epidemiology, a tool capable of monitoring 24 h movement behaviours including sleep, physical activity, and sedentary behaviour is needed. This study explores compliance with a novel dual-accelerometer system for capturing 24 h movement patterns in two free-living samples of children and adults. A total of 103 children aged 8 years and 83 adults aged 20-60 years were recruited. Using a combination of medical dressing and purpose-built foam pouches, participants were fitted with two Axivity AX3 accelerometers—one to the thigh and the other to the lower back—for seven 24 h periods. AX3 accelerometers contain an inbuilt skin temperature sensor that facilitates wear time estimation. The median (IQR) wear time in children was 160 (67) h and 165 (79) h (out of a maximum of 168 h) for back and thigh placement, respectively. Wear time was significantly higher and less variable in adults, with a median (IQR) for back and thigh placement of 168 (1) and 168 (0) h. A greater proportion of adults (71.6%) achieved the maximum number of complete days when compared to children (41.7%). We conclude that a dual-accelerometer protocol using skin attachment methods holds considerable promise for monitoring 24-h movement behaviours in both children and adults.

Does school physical education really contribute to accelerometer-measured daily physical activity and non sedentary behaviour in high school students?

Physical education has been highlighted as an important environment for physical activity promotion, however, to our knowledge there are no previous studies examining the contribution of physical education to daily accelerometer-measured physical activity and non sedentary behaviour. The purpose was to compare the accelerometer-measured physical activity and sedentary behaviour between physical education, non-physical education and weekend days in adolescents. Of the 394 students from a Spanish high school that were invited to participate, 158 students (83 boys and 75 girls) aged 13-16 years were analyzed (wear time ≥ 600 min). Participants' physical activity and sedentary behaviour were objectively-measured by GT3X+ accelerometers during physical education (one session), non-physical education and weekend days. Results indicated that overall adolescents had statistically significant greater physical activity levels and lower values of sedentary behaviour on physical education days than on non-physical education and weekend days (e.g., moderate-to-vigorous physical activity = 71, 54 and 57 min; sedentary = 710, 740 and 723 min) (p < 0.05). Physical education contributes significantly to reducing students' daily physical inactivity and sedentary behaviour. Increasing the number of physical education classes seems to be an effective strategy to reduce the high current prevalence of physical inactivity and sedentary behaviour in adolescence.

Validity and reliability of the Fitbit Zip as a measure of preschool children's step count

OBJECTIVES

Validation of physical activity measurement tools is essential to determine the relationship between physical activity and health in preschool children, but research to date has not focused on this priority. The aims of this study were to ascertain inter-rater reliability of observer step count, and interdevice reliability and validity of Fitbit Zip accelerometer step counts in preschool children.

METHODS

Fifty-six children aged 3-4 years (29 girls) recruited from 10 nurseries in North Wales, UK, wore two Fitbit Zip accelerometers while performing a timed walking task in their childcare settings. Accelerometers were worn in secure pockets inside a custom-made tabard. Video recordings enabled two observers to independently code the number of steps performed in 3 min by each child during the walking task. Intraclass correlations (ICCs), concordance correlation coefficients, Bland-Altman plots and absolute per cent error were calculated to assess the reliability and validity of the consumer-grade device.

RESULTS

An excellent ICC was found between the two observer codings (ICC=1.00) and the two Fitbit Zips (ICC=0.91). Concordance between the Fitbit Zips and observer counts was also high (r=0.77), with an acceptable absolute per cent error (6%-7%). Bland-Altman analyses identified a bias for Fitbit 1 of 22.8±19.1 steps with limits of agreement between -14.7 and 60.2 steps, and a bias for Fitbit 2 of 25.2±23.2 steps with limits of agreement between -20.2 and 70.5 steps.

CONCLUSIONS

Fitbit Zip accelerometers are a reliable and valid method of recording preschool children's step count in a childcare setting.

A Review of Recruitment, Adherence and Drop-Out Rates in Omega-3 Polyunsaturated Fatty Acid Supplementation Trials in Children and Adolescents

INTRODUCTION

The influence of n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) supplementation on health outcomes has been studied extensively with randomized controlled trials (RCT). In many research fields, difficulties with recruitment, adherence and high drop-out rates have been reported. However, what is unknown is how common these problems are in n-3 LCPUFA supplementation studies in children and adolescents. Therefore, this paper will review n-3 LCPUFA supplementation studies in children and adolescents with regard to recruitment, adherence and drop-out rates.

METHODS

The Web of Science, PubMed and Ovid databases were searched for papers reporting on RCT supplementing children and adolescents (2-18 years) with a form of n-3 LCPUFA (or placebo) for at least four weeks. As a proxy for abiding to CONSORT guidelines, we noted whether manuscripts provided a flow-chart and provided dates defining the period of recruitment and follow-up.

RESULTS

Ninety manuscripts (reporting on 75 studies) met the inclusion criteria. The majority of the studies did not abide by the CONSORT guidelines: 55% did not provide a flow-chart, while 70% did not provide dates. The majority of studies provided minimal details about the recruitment process. Only 25 of the 75 studies reported an adherence rate which was on average 85%. Sixty-five of the 75 studies included drop-out rates which were on average 17%.

CONCLUSION

Less than half of the included studies abided by the CONSORT guidelines (45% included a flow chart, while 30% reported dates). Problems with recruitment and drop-out seem to be common in n-3 LCPUFA supplementation trials in children and adolescents. However, reporting about recruitment, adherence and dropout rates was very heterogeneous and minimal in the included studies. Some techniques to improve recruitment, adherence and dropout rates were identified from the literature, however these techniques may need to be tailored to n-3 LCPUFA supplementation studies in children and adolescents.

Methodological considerations and impact of school-based interventions on objectively measured physical activity in adolescents: a systematic review and meta-analysis

OBJECTIVE

The aims of this systematic review and meta-analysis are (i) to determine the impact of school-based interventions on objectively measured physical activity among adolescents and (ii) to examine accelerometer methods and decision rule reporting in previous interventions.

METHODS

A systematic search was performed to identify randomized controlled trials targeting adolescents (age: ≥10 years), conducted in the school setting, and reporting objectively measured physical activity. Random effects meta-analyses were conducted to determine the pooled effects of previous interventions on total and moderate-to-vigorous physical activity. Potential moderators of intervention effects were also explored.

RESULTS

Thirteen articles met the inclusion criteria, and twelve were included in the meta-analysis. The pooled effects were small and non-significant for both total physical activity (standardized mean difference = 0.02 [95% confidence interval = -0.13 to 0.18]) and moderate-to-vigorous physical activity (standardized mean difference = 0.24 [95% confidence interval = -0.08 to 0.56]). Sample age and accelerometer compliance were significant moderators for total physical activity, with a younger sample and higher compliance associated with larger effects.

CONCLUSION

Previous school-based physical activity interventions targeting adolescents have been largely unsuccessful, particularly for older adolescents. There is a need for more high-quality research using objective monitoring in this population. Future interventions should comply with best-practice recommendations regarding physical activity monitoring protocols.

A non-equivalent group pilot trial of a school-based physical activity and fitness intervention for 10-11 year old english children: born to move

Background

PE lessons are the formal opportunity in schools for promotion of physical activity and fitness. This study aimed to evaluate the effectiveness of a pilot PE intervention on physical activity, fitness, and psychosocial outcomes.

Methods

Participants were 139 children aged 10–11 years from four schools. For six weeks children in two schools received a twice-weekly pilot ‘Born to Move’ (BTM) physical activity (PA) and fitness intervention alongside one regular PE lesson. Children in the two comparison (COM) schools received their regular twice weekly PE lessons. Outcomes were lesson time and whole-day light (LPA), moderate (MPA), vigorous (VPA), and MVPA, and sedentary time, muscular fitness, cardiorespiratory fitness (CRF), and lesson-specific perceived exertion, enjoyment, and perceived competence. Outcomes were assessed at baseline (T0), midway through the intervention (T1), and at the end (T2) using ANOVAs and ANCOVAs. Intervention fidelity was measured using child and teacher surveys at T2 and analysed using Chi-square tests.

Results

The BTM group engaged in moderate PA for significantly more lesson time (29.4 %) than the COM group (25.8 %; p = .009, d = .53). The amount of moderate-to-vigorous PA (MVPA) during the T1 BTM lesson contributed 14.0 % to total MVPA, which was significantly more than the COM group’s T1 PE lesson (11.4 %; p < .001, d = .47). The BTM group were significantly more active during the whole-day (p < .05) and the school-day (p < .01). In both groups push-up test performance increased (p < .001) and CRF test performance decreased (p < .01). Perceived exertion, enjoyment, and perceived competence increased in both groups (p < .05), but the BTM group rated their enjoyment of the T1 BTM lesson higher than the COM group rated their PE lesson (p = .02, d = .56). The children’s and teachers’ responses to the intervention indicated that the delivery aims of enjoyment, engagement, inclusivity, and challenge were satisfied.

Conclusions

The BTM pilot programme has potential to positively impact on physical activity, fitness, and psychosocial outcomes. Further, BTM was enjoyed by the children, and valued by the teachers. This study can inform the design of a modified larger-scale cluster RCT evaluation.