Physical activity questionnaire for adolescents validated against doubly labelled water

Longitudinal Follow-Up on Cardiopulmonary Exercise Capacity Related to Cardio-Metabolic Risk Factors in Children With Renal Transplants

Background: Children with chronic kidney disease, including those treated with kidney transplantation (KT), have an increased risk of cardiovascular disease. The aim of this study was to examine the cardiopulmonary exercise capacity after KT compared to matched controls, to relate the results to physical activity, blood pressure and biochemical findings and to follow exercise capacity over time.

Methods: Patients with KT (n = 38, age 7.7–18 years), with a mean time from transplantation of 3.7 years (0.9–13.0) and mean time in dialysis 0.8 years, were examined at inclusion and annually for up to three years. Healthy controls (n = 17, age 7.3–18.6 years) were examined once. All subjects underwent a cardiopulmonary exercise test, resting blood pressure measurement, anthropometry and activity assessment. Patients also underwent echocardiography, dual-energy X-ray absorptiometry (DXA), 24-h ambulatory BP measurements (ABPM), assessment of glomerular filtration rate (GFR) and blood sampling annually.

Results: As compared to healthy controls, KT patients showed decreased exercise capacity measured both as VO_2peak (34.5 vs. 43.9 ml/kg/min, p < 0.001) and maximal load (2.6 vs. 3.5 W/kg, p < 0.0001), similarly as when results were converted to z-scores. No significant difference was found in weight, but the KT patients were shorter and had higher BMI z-score than controls, as well as increased resting SBP and DBP z-scores. The patient or parent reported physical activity was significantly lower in the KT group compared to controls (p < 0.001) In the combined group, the major determinants for exercise capacity z-scores were activity score and BMI z-score (β = 0.79, p < 0.0001 and β = −0.38, p = 0.007, respectively). Within the KT group, low exercise capacity was associated with high fat mass index (FMI), low activity score, low GFR and high blood lipids. In the multivariate analysis FMI and low GFR remained predictors of low exercise capacity. The longitudinal data for the KT patients showed no change in exercise capacity z-scores over time.

Conclusion: Patients with KT showed decreased exercise capacity and increased BP as compared to healthy controls. Exercise capacity was associated to GFR, physical activity, FMI and blood lipids. It did not improve during follow-up.

Dietary Sugar Intake and Its Association with Obesity in Children and Adolescents

Sugar intake has been associated with increased prevalence of childhood overweight/obesity; however, results remain controversial. The aim of this study was to examine the probability of overweight/obesity with higher sugar intakes, accounting for other dietary intakes. Data from 1165 children and adolescents aged ≥2–18 years (66.8% males) enrolled in the Hellenic National Nutrition and Health Survey (HNNHS) were used; specifically, 781 children aged 2–11 years and 384 adolescents 12–18 years. Total and added sugar intake were assessed using two 24 h recalls (24 hR). Foods were categorized into specific food groups to evaluate the main foods contributing to intakes. A significant proportion of children (18.7%) and adolescents (24.5%) exceeded the recommended cut-off of 10% of total energy intake from added sugars. Sweets (29.8%) and processed/refined grains and cereals (19.1%) were the main sources of added sugars in both age groups, while in adolescents, the third main contributor was sugar-sweetened beverages (20.6%). Being overweight or obese was 2.57 (p = 0.002) and 1.77 (p = 0.047) times more likely for intakes ≥10% of total energy from added sugars compared to less <10%, when accounting for food groups and macronutrient intakes, respectively. The predicted probability of becoming obese was also significant with higher total and added-sugar consumption. We conclude that high consumption of added sugars increased the probability for overweight/obesity among youth, irrespectively of other dietary or macronutrient intakes.

Comparison of total and activity energy expenditure estimates from physical activity questionnaires and doubly labelled water: a systematic review and meta-analysis

Physical activity questionnaires (PAQ) could be suitable tools in free-living people for measures of physical activity, total and activity energy expenditure (TEE and AEE). This meta-analysis was performed to determine valid PAQ for estimating TEE and AEE using doubly labelled water (DLW). We identified data from relevant studies by searching Google Scholar, PubMed and Scopus databases. This revealed thirty-eight studies that had validated PAQ with DLW and reported the mean differences between PAQ and DLW measures of TEE (TEEDLW - TEEPAQ) and AEE (AEEDLW - AEEPAQ). We assessed seventy-eight PAQ consisting of fifty-nine PAQ that assessed TEE and thirty-five PAQ that examined AEE. There was no significant difference between TEEPAQ and TEEDLW with a weighted mean difference of -243·3 and a range of -841·4 to 354·6 kJ/d, and a significant weighted mean difference of AEEDLW - AEE PAQ 414·6 and a range of 78·7-750·5. To determine whether any PAQ was a valid tool for estimating TEE and AEE, we carried out a subgroup analysis by type of PAQ. Only Active-Q, administered in two seasons, and 3-d PA diaries were correlated with TEE by DLW at the population level; however, these two PAQ did not demonstrate an acceptable limit of agreement at individual level. For AEE, no PAQ was correlated with DLW either at the population or at the individual levels. Active-Q and 3-d PA diaries were identified as the only valid PAQ for TEE estimation. Further well-designed studies are needed to verify this result and identify additional valid PAQ.

The factors related to a sedentary lifestyle: A meta-analysis review

AIMS

To compare factors associated with the sedentary lifestyle described in the literature with the factors listed in NANDA International.

DESIGN

Systematic review with meta-analysis of factors associated with a sedentary lifestyle in adolescents, adults and older people.

DATA SOURCES

An electronic search of PubMed, Scopus, CINAHL and Latin America and the Caribbean Literature on Health and Science databases conducted in May 2016.

REVIEW METHODS

Descriptive data were extracted according to a standardized form. The odds ratios for each etiological factor associated with a sedentary lifestyle were extracted directly from the articles or calculated from the data described therein. The meta-analysis was conducted for factors that were investigated in more than one study.

RESULTS

Thirty-five articles were included. The statistically significant factors were: lack of social support, of physical space, of time, of motivation, of sports skills and of interest in physical activity, intolerance to activity, being retired, living in a low-income country, laziness, not having a job/studying, low socioeconomic status and level of knowledge about physical activity, female gender, living in an urban area, negative self-perception of health, using public transportation, being in the oldest age group in the study and perceived physical disability.

CONCLUSION

The new factors associated with a sedentary lifestyle and those already included in the NANDA International classification will lead to better clinical guidance for nurses.

IMPACT

Knowledge about these factors can contribute directly to public health policies.

Effect of soluble corn fiber supplementation for 1 year on bone metabolism in children, the MetA-bone trial: Rationale and design

Calcium intake is critical for adequate bone mineralization in adolescence, but it is usually inadequate in US adolescents. A strategy to maximize bone mineralization is to increase calcium absorption, which could be achieved by soluble corn fiber (SCF). There are no studies determining the long-term effects of SCF on bone mass in children.

OBJECTIVES

To determine the effect of one-year SCF supplementation compared to placebo on bone mass and bone biomarkers in children with low habitual calcium intake. We hypothesize that SCF supplementation will result in a higher bone mineral content and higher levels of bone formation and lower bone resorption biomarkers.

METHODS

240 healthy children (10-13 years), with usual low calcium intake, will be randomized to four experimental groups for 1 year: (1) SCF (12 g/d); (2) SCF (12 g/d) + 600 mg/d of calcium; (3) Placebo (maltodextrin); and (4) Placebo +600 mg/d of calcium. The supplements have been pre-mixed with a flavored powder beverage and participants will only need to dilute it in water and drink this twice per day. Bone will be measured using dual energy x-ray absorptiometry (DXA) at baseline, 6 and 12 months. Serum bone biomarkers will be measured at baseline and at 12 months.

CONCLUSIONS

If supplementing diets with SCF lead to higher bone mass during adolescence, this could help achieve the genetic potential for PBM and to start adult life with stronger bones. If successful, SCF can be incorporated into diets for promoting bone health in adolescents.

Sleep Hours: Risk behavior in adolescents from different countries

The aim of this study was to verify sleep hours and associated factors among Brazilian and Spanish students. A cross-sectional study with students aged 11 to 16 years-old was carried out in Paranavaí, Brasil (n = 264) and Cáceres, Spain (n = 233) between 2013 and 2015. Sleeping hours were verified regarding time in minutes, sleep in weekdays, weekends and after lunch/Siesta. All data were checked for normality by the Kolmogorov-Smirnov test. Mann-Whitney U test, Chi-square test (X2) and Odds Ratio estimates were used (p < 0.05). High prevalence in both groups of sleeping 8 hours or more a night at the weekend. The prevalence of sleeping on weekdays, > 8 hours, 6 to 8 hours and < 6 hours among Spanish and Brazilian students, respectively. Nearly a quarter of each group responded that makes the siesta. Spanish students had 3 times higher chance to sleep < 8 hours a night in weekdays, among students from 14 to 16 years old and among the underactive. At the weekends the chance of sleeping < 8 hours is 2 times greater among the Spanish students. Simple guidelines could help so that sleep habits do not affect school development, such as practicing physical activity regularly, sleeping at least 8 hours a night, avoid excessive access to technology at night.

Differential prevalence and associations of overweight and obesity by gender and population group among school learners in South Africa: a cross-sectional study

BACKGROUND

Factors influencing the increasing prevalence of overweight/obesity among children and adolescents in sub-Saharan Africa remain unclear. We assessed the prevalence and determinants of overweight and obesity and effects on cardio-metabolic profile in school learners in the Western Cape, South Africa.

METHODS

Cross-sectional data were collected from 7 to 18-year-old South African school learners attending 14 schools, randomly selected from 107 government schools in the areas. The learners were selected through stratified random sampling techniques. Logistic regressions were used to assess the determinants of overweight/obesity and its association with cardio-metabolic profile.

RESULTS

Among the 1559 participants, the overall prevalence of overweight/obesity was 22.9%. Being a girl (Odds ratio 2.51, 95% CI: 1.92-3.29), or Black African (1.35, 1.04-.75) was associated with increased odds of being overweight/obese. The identified health consequences among the overweight/obese learners differed between the ethnic groups. Overweight/obese coloured (mixed ancestry) learners were more likely to have hypertension (3.27, 1.18-9.08), hypertriglyceridemia (1.94, 0.99-3.78) and low high-density lipoprotein cholesterol (HDL-C) (3.65, 2.33-5.72), overweight/obese Black African learners had higher odds for hypertension (3.62, 1.31-10.04) and low HDL-C (1.56, 1.01-2.40) and overweight/obese White learners were prone to low HDL-C (5.04, 1.35-18.80).

CONCLUSIONS

Overweight/obesity is highly prevalent among school learners in Western Cape (South Africa), with being female or Black African increasing the odds. That overweight/obesity is also associated with adverse cardio-metabolic risk profile aggravates the problem and suggests worse cardiovascular outcomes in South African young adults in the future.

Association between Dietary Inflammatory Index (DII) and risk of prediabetes: a case-control study

The possible relationship between diet-related inflammation and the risk of prediabetes requires further investigation, especially in non-Western populations. We examined the ability of the dietary inflammatory index (DII) to predict the risk of prediabetes in a case-control study conducted at specialized centers in Esfahan, Iran. A total of 214 incident cases of prediabetes were selected with the nonrandom sampling procedure, and the 200 controls randomly selected from the same clinics were frequency-matched on age (±5 years) and sex. DII scores were computed based on dietary intake assessed using a validated and reproducible 168-item food-frequency questionnaire. Linear and logistic regression models were used to estimate multivariable beta estimates and odds ratios (ORs). Subjects in tertile 3 versus tertile 1 (T3VS1) of DII had significantly higher fasting plasma glucose (DII_T3VS1: b = 4.49; 95% CI 1.89, 7.09), oral glucose tolerance (DII_T3VS1: b = 8.76; 95% CI 1.78, 15.73), HbA1c (DII_T3VS1: b = 0.30; 95% CI 0.17, 0.42), low-density lipoprotein (DII_T3VS1: b = 16.37; 95% CI 11.04, 21.69), triglyceride (DII_T3VS1: b = 21.01; 95% CI 8.61, 33.42) and body fat (DII_T3VS1: b = 2.41; 95% CI 0.56, 4.26) and lower high-density lipoprotein (DII_T3VS1: b = -3.39; 95% CI -5.94, -0.84) and lean body mass (DII_T3VS1: b = -3.11; 95% CI -4.83, -1.39). After multivariate adjustment, subjects in the most pro-inflammatory DII group had 19 times higher odds of developing prediabetes compared with subjects in tertile 1 (DII_T3VS1: OR = 18.88; 95% CI 7.02, 50.82). Similar results were observed when DII was used as a continuous variable, (DII_continuous: OR = 3.62; 95% CI 2.50, 5.22). Subjects who consumed a more pro-inflammatory diet were at increased risk of prediabetes compared with those who consumed a more anti-inflammatory diet.

Neighborhood Characteristics: Influences on Pain and Physical Function in Youth at Risk for Chronic Pain

Neighborhood features such as community socioeconomic status, recreational facilities, and parks have been correlated to the health outcomes of the residents living within those neighborhoods, especially with regard to health-related quality of life, body mass index, and physical activity. The interplay between one’s built environment and one’s perceptions may affect physical health, well-being, and pain experiences. In the current study, neighborhood characteristics and attitudes about physical activity were examined in a high-risk (youths with a parent with chronic pain) and low-risk (youths without a parent with chronic pain) adolescent sample. There were significant differences in neighborhood characteristics between the high-risk (n = 62) and low-risk (n = 77) samples (ages 11–15), with low-risk participants living in residences with more walkability, closer proximity to parks, and higher proportion of neighborhood residents having college degrees. Results indicate that neighborhood features (e.g., walkability and proximity to parks), as well as positive attitudes about physical activity were correlated with lower levels of pain and pain-related disability, and higher performance in physical functioning tests. These findings suggest that the built environment may contribute to pain outcomes in youth, above and beyond the influence of family history of pain.

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 behavioral elements (leisure-time physical activity) and cognitive assessment of those elements (leisure-time physical activity efficacy).

Physical activity level is not a determinant of autonomic nervous system activity and clinical severity in children/adolescents with sickle cell anemia: A pilot study

BACKGROUND

Autonomic nervous system (ANS) activity has been suggested to modulate the clinical severity of sickle cell anemia (SCA) by increasing the risk for vaso-occlusive events. Regular physical activity (PA) is known to improve ANS activity and health status in several cardiovascular and metabolic diseases. Whether regular PA improves the health status of SCA patients remains unknown.

PROCEDURE

Twenty-two patients with SCA and 15 healthy (AA) children/adolescents participated to the study. Heart rate variability was measured in supine position and after a tilt-test to quantify the ANS activity. PA energy expenditure (PAEE) was assessed with questionnaire.

RESULTS

1) PAEE was lower in SCA compared to AA (190 ± 152 vs. 432 ± 277 kcal · d(-1), respectively, P < 0.01), 2) overall ANS activity was lower in SCA compared to AA, 3) parasympathetic withdrawal was observed in SCA with aging, 4) ANS reactivity was slightly impaired in SCA compared to AA (reduction in HFnu: -38 ± 27 vs. -58 ± 14%, respectively, P < 0.05), 5) ANS indices, PAEE, and rates of clinical events were not correlated.

CONCLUSION

Both the level of PA and ANS activity are reduced in SCA compared to AA children/adolescents, particularly in those older than 15 years. Neither PAEE, nor ANS activity seem to influence the clinical severity of children/adolescents with SCA.

Accuracy of self-reported physical activity levels in obese adolescents

Introduction. Self-reported measures of habitual physical activity rely completely on the respondent's ability to provide accurate information on their own physical activity behaviours. Our aim was to investigate if obese adolescents could accurately report their physical activity levels (PAL) using self-reported diaries. Methods. Total energy expenditure (TEE) was measured using doubly labelled water (DLW) and resting energy expenditure (REE) was measured via indirect calorimetry. Activity energy expenditure (AEE) and PAL values were derived from measured TEE and REE. Self-reported, four-day activity diaries were used to calculate daily MET values and averaged to give an estimated PAL value (ePAL). Results. Twenty-two obese adolescents, mean age 13.2 ± 1.8 years, mean BMI 31.3 ± 4.6 kg/m², completed the study. No significant differences between mean measured and estimated PAL values were observed (1.37 ± 0.13 versus 1.40 ± 0.34, P = 0.74). Bland Altman analysis illustrated a significant relationship (r = −0.76, P < 0.05) between the two methods; thus the bias was not consistent across a range of physical activity levels, with the more inactive overreporting their physical activity. Conclusion. At an individual level, obese adolescents are unlikely to be able to provide an accurate estimation of their own activity.

Assessment of physical activity and energy expenditure: an overview of objective measures

The ability to assess energy expenditure (EE) and estimate physical activity (PA) in free-living individuals is extremely important in the global context of non-communicable diseases including malnutrition, overnutrition (obesity), and diabetes. It is also important to appreciate that PA and EE are different constructs with PA defined as any bodily movement that results in EE and accordingly, energy is expended as a result of PA. However, total energy expenditure, best assessed using the criterion doubly labeled water (DLW) technique, includes components in addition to physical activity energy expenditure, namely resting energy expenditure and the thermic effect of food. Given the large number of assessment techniques currently used to estimate PA in humans, it is imperative to understand the relative merits of each. The goal of this review is to provide information on the utility and limitations of a range of objective measures of PA and their relationship with EE. The measures discussed include those based on EE or oxygen uptake including DLW, activity energy expenditure, physical activity level, and metabolic equivalent; those based on heart rate monitoring and motion sensors; and because of their widespread use, selected subjective measures.

Bidirectional associations between pain and physical activity in adolescents

OBJECTIVES

The objectives were to: (1) examine temporal relationships between pain and activity in youth, specifically, whether physical activity affects pain intensity and whether intensity of pain affects subsequent physical activity levels on a daily basis, and (2) examine clinical predictors of this relationship.

METHODS

Participants were 119 adolescents (59 with chronic pain and 60 healthy) aged 12 to 18 years, 71% female. Adolescents completed 10 days of actigraphic monitoring of physical activity and daily electronic diary recordings of pain intensity, medication use, sleep quality, and mood. Linear mixed models assessed daily associations among physical activity and pain. Daily mean (average count/min) and peak (highest daily level) activity were used for analyses. Medication use, sleep quality, and mood ratings were included as covariates, and age, sex, and body mass index percentile were adjusted for.

RESULTS

Higher pain intensity was associated with lower peak physical activity levels on the next day (t641=-2.25, P=0.03) and greater medication use predicted lower mean physical activity levels the same day (t641=-2.10, P=0.04). Higher mean physical activity levels predicted lower pain intensity ratings at the end of the day (t705=-2.92, P=0.004), but only in adolescents with chronic pain.

DISCUSSION

Youth experiencing high pain intensity limit their physical activity level on a day-to-day basis. Activity was related to subsequent pain intensity, and may represent an important focus in chronic pain treatment. Further study of the effect of medications on subsequent activity is needed.

An evaluation of questionnaires assessing physical activity levels in youth populations

The aim of this study was to revise and organize according to recall time based criteria, questionnaires created and validated to assess the level of physical activity in children and adolescents, with the intention of enabling their proper understanding and subsequent use by nurses and health care professionals. In order to determine the questionnaires' quality, their degree of reliability and validity was the main feature to be taken into account. Thirty-eight papers were retrieved and analyzed, 31 of which were aimed at designing and validating a questionnaire intended for physical activity (PA) level assessment in youth populations (four to 19 year olds). The most widely used questionnaires were those whose recall time spans from one to seven days. In general, all questionnaires were characterized by the use of pen-and-paper format and scarce utilization of new technologies. Based upon validity and reliability criteria, in order to assess PA level in children and adolescents, nurses should use the "Children's Leisure Activities Study Survey" and the "Flemish Physical Activity Computer Questionnaire", respectively. There is a need for the validation of these tools in other languages and cultures.

Doubly labeled water validation of a computerized use-of-time recall in active young people

OBJECTIVE

Low levels of daily energy expenditure (insufficient physical activity and increased sedentary time) have been associated with adverse health outcomes in young people. The Multimedia Activity Recall for Children and Adolescents (MARCA) is a computerized, self-report, use-of-time tool that can assess daily energy expenditure. The study aim was to validate the MARCA for the estimation of energy expenditure in young people, using the criterion standard doubly labeled water.

MATERIALS/METHODS

Over a 15 day assessment period, 32 participants (10-18 years) completed the MARCA and underwent a doubly labeled water protocol. Indirect calorimetry was used to assess resting metabolic rate. Total daily energy expenditure (TEE) and activity-related energy expenditure (AEE) were estimated from both the MARCA and doubly labeled water. Association and agreement between methods for TEE and AEE were assessed using Spearman correlations and Bland-Altman plots, respectively.

RESULTS

Compared to doubly labeled water, the MARCA over-estimated TEE by an average of 50 kcal/day (limits of agreement -1 589 to 1 490 kcal/day) and under-estimated AEE 105 kcal/day (limits of agreement -1 404 to 1 614 kcal/day). The MARCA showed strong correlation with doubly labeled water for TEE (rho=0.70, p<0.0001) and moderate correlation for AEE (rho=0.56, p=0.0009).

CONCLUSIONS

Overall, the MARCA indicated moderate validity for the assessment of daily TEE and AEE. The wide limits of agreement indicate the MARCA has greater utility for group-level rather than individual-level estimates.

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.

Global positive expectancies in adolescence and health-related behaviours: longitudinal models of latent growth and cross-lagged effects

Constructs representative of global positive expectancies (GPE) such as dispositional optimism and hope have been theoretically and empirically linked to many positive mental and physical health outcomes. However such expectancies' health implications for adolescents, as well as their trajectory over time, are less well understood than for adult populations. This study tested whether GPE predict the key indicators of adolescents' future physical health status, their health-related behaviours. A prospective longitudinal study design was employed whereby a diverse population-based cohort (N = 744; mean age at baseline = 12) completed three surveys over approximately 18 months. Rigorous tests of causal predominance and reciprocal effects were conducted through latent growth and cross-panel structural equation models. Results showed GPE systematically decreased during the course of the study, yet higher initial levels of GPE predicted less alcohol drinking, healthier food choice and greater physical activity over time. GPE's protective relationships towards health protective behaviours (vs. health risk behaviours that also included tobacco smoking) appear more independent from depressive symptomatology, and the primary findings were robust across socio-demographic groups.

[Validity and reliability of self-report instruments for measuring physical activity in adolescents: a systematic review]

This was a systematic review of studies on the reliability and validity of self-report instruments for measuring physical activity, or subjective measurements, in adolescents (10-18 years). Searches were conducted in databases (MEDLINE, PsycInfo, SportsDiscus, Scopus, Web of Science, SciELO, Lilacs) and in the references of the retrieved articles. Sixty-six studies met the inclusion criteria. The majority were from North America, with only 5 from Brazil. Fifty-two different instruments were identified: 42 questionnaires, 6 diaries or logs, and 4 interviews. "Test-retest" reliability varied from 0.20 to 0.98; the majority (28/50) of the coefficients showed values < 0.70. Validity coefficients showed wide variation (-0.13 to 0.88), with the majority (64/84) < or = 0.50. Only 3 instruments displayed correlations > or = 0.70. Various instruments were tested in adolescents, especially questionnaires. These instruments generally showed better "test-retest" reliability than validity.

Physical activity energy expenditure of adolescents in India

Physical activity (PA) has rarely been quantified in adolescent populations undergoing economic transition; therefore relationships with disease still remain uncertain. This study assessed whether absolute PA energy expenditure (PAEE), PAEE/kg, and PAEE/kg(FFM) could be accurately estimated using accelerometry and a questionnaire in Indian adolescents and how these values compared to those of other populations. PAEE was assessed using doubly labeled water (DLW) in 30 adolescents from Chennai, India, over seven consecutive days, simultaneous with the measurement of PA using accelerometry and a previous-week recall questionnaire. Accelerometry counts (regression analysis) and questionnaire data were used to estimate PAEE; estimates were cross-validated using the Bland-Altman method. Accelerometry data and DLW-derived PAEE were visually compared to values from four North American and European populations. For boys, 49% of the variance in DLW-derived PAEE was explained with an equation including accelerometry counts and fat-free mass (FFM). Questionnaire-derived estimates did not contribute to the explained variance in DLW derived PAEE. The group-level PA of these Indian adolescents was successfully assessed using accelerometry, but not questionnaire. DLW-derived PAEE/kg(FFM) (mean (s.d.): 53.0 (27.5) kJ/kg(FFM)/day) was lower in this group than other adolescent populations in Europe and similar to those in North America. Additionally, four boys and none of the girls accumulated ≥60 min/day of accelerometry-derived moderate intensity activity, indicating low levels of PAEE and PA in these adolescents. Further research is necessary to investigate the association between PA and health outcomes in Indian adolescents.

Measures of physical activity using cell phones: validation using criterion methods

Background

Physical activity is associated with reduced risks of many chronic diseases. Data collected on physical activity in large epidemiological studies is often based on paper questionnaires. The validity of these questionnaires is debated, and more effective methods are needed.

Objective

This study evaluates repeated measures of physical activity level (PAL) and the feasibility of using a Java-based questionnaire downloaded onto cell phones for collection of such data. The data obtained were compared with reference estimates based on the doubly labeled water method and indirect calorimetry (PAL_ref).

Method

Using a Java-based cell phone application, 22 women reported their physical activity based on two short questions answered daily over a 14-day period (PAL_cell). Results were compared with reference data obtained from the doubly labeled water method and indirect calorimetry (PAL_ref). Results were also compared against physical activity levels assessed by two regular paper questionnaires completed by women at the end of the 14-day period (PAL_quest1 and PAL_quest2). PAL_cell, PAL_quest1, and PAL_quest2 were compared with PAL_ref using the Bland and Altman procedure.

Results

The mean difference between PAL_cell and PAL_ref was small (0.014) with narrow limits of agreement (2SD = 0.30). Compared with PAL_ref, the mean difference was also small for PAL_quest1 and PAL_quest2 (0.004 and 0.07, respectively); however, the limits of agreement were wider (PAL_quest1, 2SD = 0.50 and PAL_quest2, 2SD = 0.90). The test for trend was statistically significant for PAL_quest1 (slope of regression line = 0.79, P = .04) as well as for PAL_quest2 (slope of regression line = 1.58, P < .001) when compared with PAL_ref.

Conclusion

A Java-based physical activity questionnaire administered daily using cell phones produced PAL estimates that agreed well with PAL reference values. Furthermore, the limits of agreement between PAL obtained using cell phones, and reference values were narrower than for corresponding estimates obtained using paper questionnaires. Java-based questionnaires downloaded onto cell phones may be a feasible and cost-effective method of data collection for large-scale prospective studies of physical activity.

An elevated level of physical activity is associated with normal lipoprotein(a) levels in individuals from Maracaibo, Venezuela

Coronary artery disease is the main cause of death worldwide. Lipoprotein(a) [Lp(a)], is an independent risk factor for coronary artery disease in which concentrations are genetically regulated. Contradictory results have been published about physical activity influence on Lp(a) concentration. This research aimed to determine associations between different physical activity levels and Lp(a) concentration. A descriptive and cross-sectional study was made in 1340 randomly selected subjects (males = 598; females = 712) to whom a complete clinical history, the International Physical Activity Questionnaire, and Lp(a) level determination were made. Statistical analysis was carried out to assess qualitative variables relationship by chi2 and differences between means by one-way analysis of variance considering a P value <0.05 as statistically significant. Results are shown as absolute frequencies, percentages, and mean +/- standard deviation according to case. Physical activity levels were ordinal classified as follows: low activity with 24.3% (n = 318), moderate activity with 35.0% (n = 458), and high physical activity with 40.8% (n = 534). Lp(a) concentration in the studied sample was 26.28 +/- 12.64 (IC: 25.59-26.96) mg/dL. Lp(a) concentration according to low, moderate, and high physical activity levels were 29.22 +/- 13.74, 26.27 +/- 12.91, and 24.53 +/- 11.35 mg/dL, respectively, observing statistically significant differences between low and moderate level (P = 0.004) and low and high level (P < 0.001). A strong association (chi2 = 9.771; P = 0.002) was observed among a high physical activity level and a normal concentration of Lp(a) (less than 30 mg/dL). A lifestyle characterized by high physical activity is associated with normal Lp(a) levels.

Is it possible to assess free-living physical activity and energy expenditure in young people by self-report?

BACKGROUND

It is unclear whether it is possible to accurately estimate physical activity energy expenditure (PAEE) by self-report in youth.

OBJECTIVE

We assessed the validity and reliability of 4 self-reports to assess PAEE and time spent at moderate and vigorous intensity physical activity (MVPA) over the previous week in British young people between 4 and 17 y of age.

DESIGN

PAEE and MVPA were derived from the Children's Physical Activity Questionnaire, Youth Physical Activity Questionnaire, and Swedish Adolescent Physical Activity Questionnaire; a lifestyle score indicative of habitual activity was derived from the Child Heart and Health Study in England Questionnaire. These data were compared with criterion methods, PAEE, and MVPA derived from simultaneous measurements by doubly labeled water and accelerometry in 3 age groups: 4-5 y (n = 27), 12-13 y (n = 25), and 16-17 y (n = 24). Validity was assessed by using Spearman correlations and the Bland-Altman method, and reliability was assessed by using intraclass correlation coefficients.

RESULTS

The strength of association between questionnaire and criterion methods varied (r = 0.09 to r = 0.46). Some questionnaires were able to accurately assess group-level PAEE and MVPA for some age groups, but the error was large for individual-level estimates throughout. Reliability of the Youth Physical Activity Questionnaire and Child Heart and Health Study in England Questionnaire was good (intraclass correlation coefficient: 0.64-0.92).

CONCLUSIONS

Absolute PAEE and MVPA estimated from these self-reports were not valid on an individual level in young people, although some questionnaires appeared to rank individuals accurately. Age (the outcome of interest) and whether individual or group-level estimates are necessary will influence the best choice of self-report method when assessing physical activity in youth.

Assessment of physical activity: a critical appraisal

Assessment of physical activity in a free-living environment is important for understanding relations between physical activity and health and determining the effectiveness of interventions. Techniques include behavioral observation, questionnaires in the form of diaries, recall questionnaires and interviews, and physiological markers like heart rate, calorimetry, and motion sensors. The doubly labeled water method has become the gold standard for the validation of field methods of assessing physical activity. Then, questionnaires show a low reliability and validity but can be adequately applied as an activity-ranking instrument. The heart rate requires individual calibration to be an effective method to assess physical activity only at group level. The indicated method for the assessment of habitual physical activity in daily life is a doubly labeled water validated accelerometer. Future developments are simultaneous measurement of body acceleration and heart rate for the assessment of physical fitness. A new generation of accelerometers will provide information on body posture and activity recognition to allow objective assessment of subjects' habitual activities, options for a healthy change, and effects of the follow-up of any changes.

Assessment of physical activity in youth

Despite much progress with physical activity assessment, the limitations concerning the accurate measurement of physical activity are often amplified in young people due to the cognitive, physiological, and biomechanical changes that occur during natural growth as well as a more intermittent pattern of habitual physical activity in youth compared with adults. This mini-review describes and compares methods to assess habitual physical activity in youth and discusses main issues regarding the use and interpretation of data collected with these techniques. Self-report instruments and movement sensing are currently the most frequently used methods for the assessment of physical activity in epidemiological research; others include heart rate monitoring and multisensor systems. Habitual energy expenditure can be estimated from these input measures with varying degree of uncertainty. Nonlinear modeling techniques, using accelerometry perhaps in combination with physiological parameters like heart rate or temperature, have the greatest potential for increasing the prediction accuracy of habitual physical activity energy expenditure. Although multisensor systems may be more accurate, this must be balanced against feasibility, a balance that shifts with technological and scientific advances and should be considered at the beginning of every new study.

Validity of two physical activity questionnaires (IPAQ and PAQA) for Vietnamese adolescents in rural and urban areas

BACKGROUND

Although physical activity is recognised to be an important determinant of health and nutritional status, few instruments have been developed to assess physical activity in developing countries. The aim of this study was to compare the validity of the short form of the International Physical Activity Questionnaire (IPAQ) and a locally adapted version of the Physical Activity Questionnaire for Adolescents (PAQA) for use in school going adolescents in rural and urban areas in Vietnam.

METHODS

Sixteen year old adolescents from rural areas (n = 137) and urban areas (n = 90) completed the questionnaires in 2006. Test-retest reliability was assessed by comparing registrations after 2 weeks. Criterion validity was assessed by comparison with 7 days continuous accelerometer logging. Validity of the two methods was assessed using Spearman correlation coefficient, intra class correlation coefficients (ICC) and Kappa statistics.

RESULTS

Reliability of both questionnaires was poor for both the IPAQ (ICC = 0.37) and the PAQA (ICC = 0.40). Criterion validity of both questionnaires was acceptable and similar for the IPAQ (rho = 0.21) and the PAQA (rho = 0.27) but a significantly lower validity was observed in rural areas. Both forms poorly estimated time spent on light, moderate and vigorous physical activity. Agreement of both questionnaires to classify individuals was also low but the IPAQ performed better than the PAQA.

CONCLUSION

Both questionnaires have a similar and overall poor validity to be used as a population instrument in Vietnam. Low reliability and classification properties in rural areas call for further research for specific use in such settings.

Validity of the modified Baecke questionnaire: comparison with energy expenditure according to the doubly labeled water method

Background

In epidemiological research, physical activity is usually assessed by questionnaires. Questionnaires are suitable for large study populations since they are relatively inexpensive and not very time consuming. However, questionnaire information is by definition subjective and prone to recall bias, especially among elderly subjects. The Modified Baecke Questionnaire, developed by Voorrips and coworkers, measures habitual physical activity in the elderly. The questionnaire includes questions on household activities, sports, and leisure time activities, over a time period of one year. The Modified Baecke Questionnaire results in a score to classify people as high, moderate, or low in daily physical activity, based on tertiles.

Methods

The validity of the Modified Baecke Questionnaire score was assessed among 21 elderly men and women using the doubly labeled water method as the reference criterion. This method is considered to be the gold standard for measuring energy expenditure in free-living individuals. Energy expenditure on physical activity is estimated by the ratio of total energy expenditure measured by the doubly labeled water method and resting metabolic rate measured by indirect calorimetry. This ratio is called the physical activity ratio.

Results

The Spearman correlation coefficient between the questionnaire score and the physical activity ratio (PAR) was 0.54 (95% CI 0.22–0.66). Correct classification by the questionnaire occurred in 71% of participants who were in the lowest tertile of PAR, in 14% of participants in the middle tertile, and in 43% of participants in the highest tertile. Subjects were not wrongly classified in an opposite tertile.

Conclusion

The validity of the Modified Baecke Questionnaire is fair-to-moderate. This study shows that the questionnaire can correctly classify individuals as low or high active, but does a poor job for moderately active individuals.