Pediatrics and Physical Activity

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To examine the tracking of physical activity from adolescence to young adulthood and its influence on selected coronary heart disease risk factors in a 6 year study of Finnish adolescents and young adults.

Inclusion Criteria:
Not Specified
Exclusion Criteria:
Not Specified
Description of Study Protocol:
Physical activity, anthropometric information, dietary data and smoking were assessed over a 6 year period.
Data Collection Summary:

Independent Variables:

  • Physical Activity – assessed by a questionnaire.
    • Constantly active = PA index of >85 for all 3 years.
    • Constantly sedentary = PA index of <15 for all 3 years.

Dependent Variables:

  • Obesity status – BMI was calculated and skin fold thickness.
  • Serum samples
  • Smoking (self-administered questionnaire)

Confounding: Dietary status (polyunsaturated vs saturated ratio, saturated fat and carbohydrates)

Statistical Analyses:

  • Tracking was assessed by calculating Spearman’s rank order correlation coefficients between two measurements of physical activity index 3 and 6 years apart.
  • Differences in continuous variables between groups were tested with a t test or with a nonparametric Mann-Whitney t-test.
  • Differences in proportions were tested with chi-square or Fisher’s exact test.
  • Six year change in serum total cholesterol, HDL cholesterol, triglycerides, insulin, HDL cholesterol/total cholesterol ratio, and sub-scapular skin fold thickness were modeled as dependent variables in a regression analysis.  The independent variables included change in PA index, change in sub-scapular skin fold thickness, change in smoking habits, changes in poly-unsaturated to saturated fatty acids ratio, change in saturated fat intake and change in carbohydrate intake.
Description of Actual Data Sample:

N: 1159 participants with complete data for years 1 and 2. 961 participants with data on year 1 and the last year.

Age: The children were age 3,6,9,12, 15, 18 . 

Race/Ethnicity: Not reported

Location: Finland

Summary of Results:
  • Probability of remaining physically active over 6 year period was 29-57% in girls and 41-54% in boys. Of those participants who were initially classified as sedentary in 1980, 51-63% of the girls and 54-61% of boys were considered sedentary in 1986.
  • The probability of remaining sedentary was significantly stronger than the probability of remaining active (57vs. 44%, p = .002).
  • Among young active women, physically active trackers had thinner subscapular skinfolds (10.5+ 2.9 vs. 14.2 +5.6, p = .005 compared with sedentary women.
  • Physically active men also had thinner subscapular skinfolds (9.9 +4.4 vs. 12.1 + 5.3, p = .012)
Author Conclusion:

The results of our study give support to the idea that life-style activity patterns adopted in childhood persist to adulthood, since there were significant tracking correlations between subsequent measurements.

 

Approximately 44% of subjects considered as highly active in 1980 did not change their behavioral pattern and remained active over the 6 year follow-up. Tracking of sedentary life-style was better: 57% of those initially sedentary remained sedentary at follow-up.

 

Overall conclusion:

 

Early adaptation to sedentary life-style seems to have stronger modifying effect on later activity patterns compared with adaptation to high levels of activity.

 

The level of physical activity shows tracking from adolescence to young adulthood.

Funding Source:
Government: the Academy of Finland
University/Hospital: University of Turku, University of Helsinki, University of Jyvaskyla
Not-for-profit
0
Foundation associated with industry:
Reviewer Comments:

Limitations: Didn’t address limitations.

 

Strengths: 

  • PA measure gets at multiple forms of activity
  • Large sample
  • Longitudinal
Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) N/A
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? N/A
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? N/A
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) N/A
 
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? N/A
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? N/A
  1.3. Were the target population and setting specified? N/A
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? N/A
  2.2. Were criteria applied equally to all study groups? N/A
  2.3. Were health, demographics, and other characteristics of subjects described? N/A
  2.4. Were the subjects/patients a representative sample of the relevant population? N/A
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? N/A
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) N/A
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? N/A
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? N/A
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) N/A
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? N/A
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? N/A
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? N/A
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? N/A
  7.2. Were nutrition measures appropriate to question and outcomes of concern? N/A
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? N/A
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? N/A
  7.5. Was the measurement of effect at an appropriate level of precision? N/A
  7.6. Were other factors accounted for (measured) that could affect outcomes? N/A
  7.7. Were the measurements conducted consistently across groups? N/A
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? N/A
  8.2. Were correct statistical tests used and assumptions of test not violated? N/A
  8.3. Were statistics reported with levels of significance and/or confidence intervals? N/A
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? N/A
  8.6. Was clinical significance as well as statistical significance reported? N/A
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? N/A
  9.2. Are biases and study limitations identified and discussed? N/A
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? N/A
  10.2. Was the study free from apparent conflict of interest? N/A