Validity of the Bouchard activity diary in Spanish adolescents

Measuring Physical Activity in Juvenile Idiopathic Arthritis: Activity Diary Versus Accelerometer

Objective.

(1) To determine convergent validity of an activity diary (AD) and accelerometer (Actical brand/Phillips-Respironics) in measuring physical activity (PA) in children with juvenile idiopathic arthritis (JIA). (2) To determine how many days give reliable results. (3) To analyze effects of correcting accelerometer data for non-wear.

Methods.

Patients with JIA (8–13 yrs) were recruited from 3 Dutch pediatric rheumatology centers. PA was assessed for 7 days with an AD and accelerometer, and was expressed as mean min/day of rest, light PA (LPA), moderate to vigorous PA (MVPA), and PA level (PAL). To analyze convergent validity, intraclass correlation coefficients (ICC) were calculated and paired sample Student t tests were performed. The required number of days to achieve reliable results was calculated using the Spearman-Brown prophecy formula.

Results.

Convergent validity between AD and accelerometer was moderate for rest and PAL (ICC 0.41). ICC for LPA and MVPA were < 0.24. AD overestimated PAL and MVPA compared with the accelerometer. Wearing the accelerometer 7–19 days gave reliable PA estimates on group and individual levels. For the AD, 13–36 days were needed. Adjusting accelerometer data for non-wear resulted in a clinically relevant higher mean number of min/day spent in LPA (effect size 1.12), but not in MVPA (effect size 0.44).

Conclusion.

Convergent validity between AD and accelerometer is moderate to poor. In children with JIA, 1-week assessment with an accelerometer is sufficient to measure PA (all levels) reliably. On an individual level and for clinical use, 3 weeks are required. Additional use of AD enables correction for non-wear of accelerometer data.

Measuring Physical Activity and Sedentary Behavior in Youth with Type 2 Diabetes

BACKGROUND

Lifestyle interventions that encourage increasing physical activity (PA) and losing weight are critical for overweight and obese youth with comorbid conditions. Assessing PA within such lifestyle intervention efforts requires measurement tool(s) that are both accurate and appropriate for these youth. This research compares PA levels and sedentary behavior in an ethnically diverse cohort of overweight/obese youth with type 2 diabetes using both accelerometry and a questionnaire previously validated in the general youth population.

METHODS

Spearman's correlations were used to compare time spent sedentary and in different PA intensities between a questionnaire, the three-day PA recall (3DPAR), and an objective PA measure, the ActiGraph accelerometer, in 236 overweight/obese youth with diabetes.

RESULTS

Spearman correlations between 3DPAR and accelerometer results for total PA were small and not significant (rho = 0.11, p > 0.05 for males and females). Correlations for specific PA intensities (moderate/vigorous and light) were also small and not significant. Sedentary time between instruments was significant, but weakly correlated in females (rho = 0.19, p < 0.05), but not in males (rho = 0.07, p = 0.48).

CONCLUSIONS

Subjective PA measures validated in the general youth population may not be the best method for differentiating levels of movement in overweight/obese youth with type 2 diabetes, who spend most of their time in light-intensity activity and sedentary pursuits with little or no time spent in moderate/vigorous-intensity activities. Objective measures such as accelerometers that can capture the lower end of the movement scale are likely the more appropriate measures under these conditions.

A validation study of a modified Bouchard activity record that extends the concept of 'uptime' to Rett syndrome

AIM

The aim of this study was to investigate the validity of using a Bouchard activity record (BAR) in individuals with Rett syndrome to measure physical activity, as compared with pragmatic criterion standard measures of walking status and step counts recorded using the StepWatch activity monitor (SAM).

METHOD

During the waking hours of 1 day, 43 females (mean age 21y, SD 9y) wore a SAM whilst a proxy completed a modified BAR. Responses to the BAR were compared among participants, who were grouped according to walking status, using the Mann-Whitney two-sample rank-sum test. Relationships were sought between BAR responses and step counts using linear regression.

RESULTS

According to the proxy-reported BAR responses, those who needed assistance with walking spent more time sitting (median [interquartile range] 9h 15min [8h 8min-10h 30min] vs 6h 15min [4h 15min-8h 30min]; p<0.001) and less time standing (1h [38min-1h 30min] vs 2h 15min [45min-3h 45min]; p=0.04) than those who could walk independently. In those who could walk independently, time classified as 'uptime' (standing and walking) using the BAR was associated with increased step count (r(2) =0.58; p<0.001).

INTERPRETATION

These data support the validity of proxy-reported BAR responses. In those who could walk independently, uptime, classified using the BAR, could be used to estimate daily step count. This tool offers an inexpensive method for clinicians to gain insights into physical activity levels in individuals with Rett syndrome.

A systematic review of reliability and objective criterion-related validity of physical activity questionnaires

Physical inactivity is one of the four leading risk factors for global mortality. Accurate measurement of physical activity (PA) and in particular by physical activity questionnaires (PAQs) remains a challenge. The aim of this paper is to provide an updated systematic review of the reliability and validity characteristics of existing and more recently developed PAQs and to quantitatively compare the performance between existing and newly developed PAQs.

A literature search of electronic databases was performed for studies assessing reliability and validity data of PAQs using an objective criterion measurement of PA between January 1997 and December 2011. Articles meeting the inclusion criteria were screened and data were extracted to provide a systematic overview of measurement properties. Due to differences in reported outcomes and criterion methods a quantitative meta-analysis was not possible.

In total, 31 studies testing 34 newly developed PAQs, and 65 studies examining 96 existing PAQs were included. Very few PAQs showed good results on both reliability and validity. Median reliability correlation coefficients were 0.62–0.71 for existing, and 0.74–0.76 for new PAQs. Median validity coefficients ranged from 0.30–0.39 for existing, and from 0.25–0.41 for new PAQs.

Although the majority of PAQs appear to have acceptable reliability, the validity is moderate at best. Newly developed PAQs do not appear to perform substantially better than existing PAQs in terms of reliability and validity. Future PAQ studies should include measures of absolute validity and the error structure of the instrument.

Practical physical activity measurement in youth: a review of contemporary approaches

BACKGROUND

The accurate evaluation of physical activity levels amongst youth is critical for quantifying physical activity behaviors and evaluating the effect of physical activity interventions. The purpose of this review is to evaluate contemporary approaches to physical activity evaluation amongst youth.

DATA SOURCES

The literature from a range of sources was reviewed and synthesized to provide an overview of contemporary approaches for measuring youth physical activity.

RESULTS

Five broad categories are described: self-report, instrumental movement detection, biological approaches, direct observation, and combined methods. Emerging technologies and priorities for future research are also identified.

CONCLUSIONS

There will always be a trade-off between accuracy and available resources when choosing the best approach for measuring physical activity amongst youth. Unfortunately, cost and logistical challenges may prohibit the use of "gold standard" physical activity measurement approaches such as doubly labelled water. Other objective methods such as heart rate monitoring, accelerometry, pedometry, indirect calorimetry, or a combination of measures have the potential to better capture the duration and intensity of physical activity, while self-reported measures are useful for capturing the type and context of activity.

Convergent validity of the Arab Teens Lifestyle Study (ATLS) physical activity questionnaire

The Arab Teens Lifestyle Study (ATLS) is a multicenter project for assessing the lifestyle habits of Arab adolescents. This study reports on the convergent validity of the physical activity questionnaire used in ATLS against an electronic pedometer. Participants were 39 males and 36 females randomly selected from secondary schools, with a mean age of 16.1 ± 1.1 years. ATLS self-reported questionnaire was validated against the electronic pedometer for three consecutive weekdays. Mean steps counts were 6,866 ± 3,854 steps/day with no significant gender difference observed. Questionnaire results showed no significant gender differences in time spent on total or moderate-intensity activities. However, males spent significantly more time than females on vigorous-intensity activity. The correlation of steps counts with total time spent on all activities by the questionnaire was 0.369. Relationship of steps counts was higher with vigorous-intensity (r = 0.338) than with moderate-intensity activity (r = 0.265). Pedometer steps counts showed higher correlations with time spent on walking (r = 0.350) and jogging (r = 0.383) than with the time spent on other activities. Active participants, based on pedometer assessment, were also most active by the questionnaire. It appears that ATLS questionnaire is a valid instrument for assessing habitual physical activity among Arab adolescents.

Validation of the Netherlands physical activity questionnaire in Brazilian children

BACKGROUND

Physical activity instruments can be subjective or objective. There is a need to assess the reliability of these instruments, especially for researches in children. The aim of this study was to determine the validity of the Netherlands Physical Activity Questionnaire (NPAQ).

METHODS

Population under study were Brazilian children aged 4 to 11 years old, enrolled in a population-based study. Data collection took place in two distinct moments: 1) application of the NPAQ by face-to-face interviews with mothers' children and 2) utilization of accelerometers by children as the reference method. GT1M Actigraph accelerometer was worn for five consecutive days. Validity analyses were performed by sensitivity and specificity and ROC (Receiver Operator Characteristic) curve.

RESULTS

Two hundred and thirty nine children participated in both phases of the study. A total of 73.2% children achieved the recommendation of 60 min/day of moderate to vigorous physical activity. The mean and median of the NPAQ score were 25.5 and 26, respectively. The score ranged from 7 to 35 points. The correlation coefficient between the NPAQ and the time spent in moderate to vigorous physical activities was 0.27. Based on the area under the ROC curve, the median value presented the best indicators of sensitivity (59.4%) and specificity (60.9%), and the area under curve was 0.63. The predictive capacity of the NPAQ to identify active children was high regardless the cut-off point chosen. This capacity was even higher if the score was higher than 30.

CONCLUSIONS

Based on sensitivity and specificity values, the NPAQ did not show satisfactory validity. The comparison of the reliability of the NPAQ with other instruments is limited, but correlation coefficients found in this study are similar to others. Physical activity level of children estimated from the NPAQ must be interpreted cautiously, and objective measures such as accelerometers should be encouraged.

[Determining factors of physical activity level in school children and adolescents: the OPACA study]

INTRODUCTION

Physical activity is a key factor for human health. This study attempts to measure the level of physical activity in children and to find out what are the factors that determine it.

METHOD

In a sample of the 11 and 14 year-old population of the centre-south area of Palencia, physical activity was measured using a three day diary, and anthropometric and socioeconomic variables were collected. Three variables were analysed: fat-free mass adjusted activity energy expenditure (AEE/FFM), physical activity level (PAL), and categorical physical activity (active/inactive).

RESULTS

A total of 179 children were included, of whom 71.5% were active or very active. Males were more active than females, and activity was also higher in summer. Physical activity declined between 11 and 14 years, and was lower during the weekends than in working days. There were no differences related to obesity, overweight or percent body fat. More active children had lower blood pressure. Physical activity was directly related to weekly hours spent in sport activities, and inversely related to time spent on sedentary activities. Multivariate analysis showed that children from families with low educational levels had a higher activity level not related to sport activities.

CONCLUSIONS

The level of physical activity in this population is acceptable, although there are sex differences and there is a declining trend through the adolescence.

Convergent validity of a questionnaire for assessing physical activity in Spanish adolescents with overweight

OBJECTIVE

To evaluate the convergent validity of the PAQ-A for assessing physical activity (PA) in overweight (including obese) adolescents.

MATERIAL AND METHOD

Two hundred and three Spanish adolescents (96 females), aged 13-17 years, were selected for this study. Levels of PA were self-reported by 3-day activity diary, activity rating and PAQ-A. Adolescents wore the ActiGraph accelerometer for 7 days. Overweight was classified according to International Obesity Task Force age- and sex-specific body mass index cut offs.

RESULTS

Fifty-four (33 male and 21 female) adolescents (27%) were classified as overweight or obese. The PAQ-A was moderately related in the overweight adolescent group to an activity rating (ρ=0.52), total PA and moderate-to-vigorous PA assessed by activity monitor (ρ=0.52 and 0.43) and total PA and moderate-to-vigorous PA assessed by activity diary (ρ=0.32 and 0.47). There were no significant differences in the correlation coefficients between non-overweight and overweight adolescents.

CONCLUSION

The PAQ-A shows a reasonable validity for assessing PA in Spanish overweight adolescents.