Measurement and data transmission validity of a multi-biosensor system for real-time remote exercise monitoring among cardiac patients

Background: Remote telemonitoring holds great potential to augment management of patients with coronary heart disease (CHD) and atrial fibrillation (AF) by enabling regular physiological monitoring during physical activity. Remote physiological monitoring may improve home and community exercise-based cardiac rehabilitation (exCR) programs and could improve assessment of the impact and management of pharmacological interventions for heart rate control in individuals with AF.

Objective: Our aim was to evaluate the measurement validity and data transmission reliability of a remote telemonitoring system comprising a wireless multi-parameter physiological sensor, custom mobile app, and middleware platform, among individuals in sinus rhythm and AF.

Methods: Participants in sinus rhythm and with AF undertook simulated daily activities, low, moderate, and/or high intensity exercise. Remote monitoring system heart rate and respiratory rate were compared to reference measures (12-lead ECG and indirect calorimeter). Wireless data transmission loss was calculated between the sensor, mobile app, and remote Internet server.

Results: Median heart rate (-0.30 to 1.10 b∙min-1) and respiratory rate (-1.25 to 0.39 br∙min-1) measurement biases were small, yet statistically significant (all P≤.003) due to the large number of observations. Measurement reliability was generally excellent (rho=.87-.97, all P<.001; intraclass correlation coefficient [ICC]=.94-.98, all P<.001; coefficient of variation [CV]=2.24-7.94%), although respiratory rate measurement reliability was poor among AF participants (rho=.43, P<.001; ICC=.55, P<.001; CV=16.61%). Data loss was minimal (<5%) when all system components were active; however, instability of the network hosting the remote data capture server resulted in data loss at the remote Internet server during some trials.

Conclusions: System validity was sufficient for remote monitoring of heart and respiratory rates across a range of exercise intensities. Remote exercise monitoring has potential to augment current exCR and heart rate control management approaches by enabling the provision of individually tailored care to individuals outside traditional clinical environments.

A domain-specific approach for assessing physical activity efficacy in adolescents: from scale conception to predictive validity

Objective: To develop and test the utility of a domain-specific physical activity efficacy scale in adolescents for predicting physical activity behaviour. Design: Two independent studies were conducted. Study 1 examined the psychometric properties of a newly constructed Domain-Specific Physical Activity Efficacy Questionnaire (DSPAEQ) and study 2 tested the utility of the scale for predicting leisure- and school-time physical activity. Methods: In study 1, descriptive physical activity data were used to generate scale items. The scales factor structure and internal consistency were tested in a sample of 272 adolescents. A subsequent sample of Canadian (N = 104) and New Zealand (N = 29) adolescents, was recruited in study 2 to explore the scale's predictive validity using a subjective measure of leisure- and school-time physical activity. Results: A principle axis factor analysis in study 1 revealed a 26-item, five-factor coherent and interpretable solution; representative of leisure and recreation, household, ambulatory, transportation, and school physical activity efficacy constructs, respectively. The five-factor solution explained 81% of the response variance. In study 2 the domain-specific efficacy model explained 16% and 1% of leisure- and school-time physical activity response variance, respectively, with leisure time physical activity efficacy identified as a unique and significant contributor of leisure-time physical activity. Conclusion: Study 1 provides evidence for the tenability of a five factor DSPEAQ, while study 2 shows that the DSPEAQ has utility in predicting domain-specific physical activity. This latter finding underscores the importance of scale correspondence between the behavioural elements (leisure-time physical activity) and cognitive assessment of those elements (leisure-time physical activity efficacy).

Construct validity of the Dutch version of the 12-item Partners in Health scale : measuring self-management behaviour and knowledge in COPD patients

The 12-item Partner in Health (PIH) scale was developed in Australia to measure self-management behaviour and knowledge in patients with chronic diseases. The scale has undergone several changes since first published. Our study aim was to validate the latest PIH in Dutch COPD patients.The 12 items of the PIH are scored on a self-rated 9-point Likert scale (range: 0-8; higher scores indicate better self-management), providing total and subscale scores (knowledge, coping, recognition and management of functions, adherence to treatment).We used forward-backward translation of the latest version of the Australian PIH. Dimensionality and reliability analyses were performed to investigate the psychometric properties, and to determine whether the Dutch PIH replicated the same four subscales of self-management as the original PIH.Reanalysis of the original PIH validation study (186 Australian patients with chronic diseases) showed a single scale. Two scales (1. knowledge and coping; 2. recognition and management of symptoms, adherence to treatment) were found for the Dutch PIH (118 Dutch COPD patients). The correlation between the two Dutch scales was 0.43. The lower-bound of the reliability of the total scale was 0.81 (Australian PIH) and 0.84 (Dutch PIH).Different scale structures were found for the original Australian and the Dutch PIH. Our results did not support the 4-scale structure reported previously. To increase comparability and generalisability of our findings, the scale structure of the revised Australian PIH needs to be investigated further. Meanwhile, we advise using the PIH total score or two subscale scores when assessing COPD patients.

Validity of a wearable accelerometer device to measure average acceleration values during high speed running

The aim of this study was to determine the validity of an accelerometer to measure average acceleration values during high speed running. Thirteen subjects performed three sprint efforts over a 40 m distance (n = 39). Acceleration was measured using a 100 Hz tri-axial accelerometer integrated within a wearable tracking device (SPI-HPU, GPSports, Canberra). To provide a concurrent measure of acceleration, timing gates were positioned at 10 m intervals (0 m - 40 m). Accelerometer data collected during 0 m - 10 m and 10 m - 20 m provided a measure of average acceleration values. Accelerometer data was recorded as the raw output and filtered by applying a 3 point moving average and a 10 point moving average. The accelerometer could not measure average acceleration values during high speed running. The accelerometer significantly overestimated average acceleration values during both 0 m - 10 m and 10 m - 20 m, regardless of the data filtering technique (p < 0.001). Body mass significantly affected all accelerometer variables (p < 0.10, partial η = 0.091 - 0.219). Body mass and the absence of a gravity compensation formula affect the accuracy and practicality of accelerometers. Until GPSports integrated accelerometers incorporate a gravity compensation formula the usefulness of any accelerometer derived algorithms is questionable.

Validity and reliability of a pictorial instrument for assessing perceived motor competence in Portuguese children

BACKGROUND: It is important to assess young children's perceived Fundamental Movement Skill (FMS) competence in order to examine the role of perceived FMS competence in motivation toward physical activity. Children's perceptions of motor competence may vary according to the culture/country of origin; therefore, it is also important to measure perceptions in different cultural contexts. The purpose was to assess the face validity, internal consistency, test-retest reliability and construct validity of the 12 FMS items in the Pictorial Scale for Perceived Movement Skill Competence for Young Children (PMSC) in a Portuguese sample.

METHODS: Two hundred one Portuguese children (girls, n = 112), 5 to 10 years of age (7.6 ± 1.4), participated. All children completed the PMSC once. Ordinal alpha assessed internal consistency. A random subsamples (n = 47) were reassessed one week later to determine test-retest reliability with Bland-Altman method. Children were asked questions after the second administration to determine face validity. Construct validity was assessed on the whole sample with a Bayesian Structural Equation Modelling (BSEM) approach. The hypothesized theoretical model used the 12 items and two hypothesized factors: object control and locomotor skills.

RESULTS: The majority of children correctly identified the skills and could understand most of the pictures. Test-retest reliability analysis was good, with an agreement ration between 0.99 and 1.02. Ordinal alpha values ranged from acceptable (object control 0.73, locomotor 0.68) to good (all FMS 0.81). The hypothesized BSEM model had an adequate fit.

CONCLUSIONS: The PMSC can be used to investigate perceptions of children's FMS competence. This instrument can also be satisfactorily used among Portuguese children.

Construct validity of the Dutch version of the 12-item Partners in Health scale: measuring patient self-management behaviour and knowledge in patients with Chronic Obstructive Pulmonary Disease

Objective The 12-item Partners in Health scale (PIH) was developed in Australia to measure self-management behaviour and knowledge in patients with chronic diseases, and has undergone several changes. Our aim was to assess the construct validity and reliability of the latest PIH version in Dutch COPD patients.

Methods The 12 items of the PIH, scored on a self-rated 9-point Likert scale, are used to calculate total and subscale scores (knowledge; coping; recognition and management of symptoms; and adherence to treatment). We used forward-backward translation of the latest version of the Australian PIH to define a Dutch PIH (PIH(Du)). Mokken Scale Analysis and common Factor Analysis were performed on data from a Dutch COPD sample to investigate the psychometric properties of the Dutch PIH; and to determine whether the four-subscale solution previously found for the original Australian PIH could be replicated for the Dutch PIH.

Results Two subscales were found for the Dutch PIH data (n = 118); 1) knowledge and coping; 2) recognition and management of symptoms, adherence to treatment. The correlation between the two Dutch subscales was 0.43. The lower-bound of the reliability of the total scale equalled 0.84. Factor analysis indicated that the first two factors explained a larger percentage of common variance (39.4% and 19.9%) than could be expected when using random data (17.5% and 15.1%).

Conclusion We recommend using two PIH subscale scores when assessing self-management in Dutch COPD patients. Our results did not support the four-subscale structure as previously reported for the original Australian PIH.

Validity of short food questionnaire items to measure intake in children and adolescents: a systematic review

BACKGROUND: Short food questions are appealing to measure dietary intakes. METHODS: A review of studies published between 2004 and 2016 was undertaken and these were included in the present study if they reported on a question or short item questionnaire (≤50 items, data presented as ≤30 food groups) measuring food intake or food-related habits, in children (aged 6 months to 18 years), and reported question validity or reliability. Thirty studies met the inclusion criteria. RESULTS: Most questions assessed foods or food groups (n = 29), with the most commonly assessed being fruit (n = 22) or vegetable intake (n = 23), dairy foods and discretionary foods (n = 20 studies each). Four studies assessed food habits, with the most common being breakfast and meal frequency (n = 4 studies). Twenty studies assessed reliability, and 25 studies determined accuracy and were most commonly compared against food records. Evaluation of question performance relied on statistical tests such as correlation. CONCLUSIONS: The present study has identified valid and reliable questions for the range of key food groups of interest to public health nutrition. Questions were more likely to be reliable than accurate, and relatively few questions were both reliable and accurate. Gaps in repeatable and valid short food questions have been identified that will provide direction for future tool development.

Criterion validity of the activPAL™ and ActiGraph for assessing children's sitting and standing time in a school classroom setting

BACKGROUND: Few studies have investigated the accuracy of the ActiGraph (AG) GTX3 accelerometer for assessing children's sitting and standing time. The activPAL (aP) has an inclinometer function that enables it to distinguish between sitting/lying and standing; however, its accuracy for assessing sitting and standing in older children is unknown. This study validated the accuracy of these devices for estimating sitting and standing time in a school classroom against a criterion measure of direct observation (DO).

FINDINGS: Forty children in grades 5-7 wore both devices while being video recorded during two school lessons. AG and aP data were simultaneously collected in 15-s epochs. Individual participant DO and aP data were recorded as total time spent sitting/lying, standing and stepping. AG data were converted into time spent sitting and standing using previously established cut-points. Compared with DO, the aP underestimated sitting time (mean bias = -1.9 min, 95 % LoA = -8.9 to 5.2 min) and overestimated standing time (mean bias = 1.8 min, 95% LoA = -9.6 to 13.3 min). The best-performing AG cut-point across both sitting and standing (<75 counts/15 s) was more accurate than the aP, underestimating sitting time (mean bias = -0.8 min, 95 % LoA = -10.5 to 9.9 min) and standing time (mean bias = -0.4 min, 95% LoA = -9.8 to 9.1 min), but was less precise as evidenced by wider LoAs and poorer correlations with DO (sitting r = 0.86 aP vs 0.80 AG; standing r = 0.78 aP vs 0.60 AG).

CONCLUSIONS: The aP demonstrated good accuracy and precision for assessing free-living sitting and standing time in classroom settings. The AG was most accurate using a cut-point of < 75 counts/15 s. Further studies should validate the monitors in settings with greater inter- and intra-individual variation in movement patterns.