Child Nutrition and Environment
Liu GC, Cunningham C, Downs SM, Marrero DG, Fineberg N. A spatial analysis of obesogenic environments for children. Proc AMIA Symp 2002; 459-463.PubMed ID: 12463866
To describe the convergence of technologies and research efforts to deepen the understanding of the environmental context of childhood obesity and enable precise targeting of systems-based environmental prevention efforts.
- Children and adolescents aged four to 18 in the calendar year 2000
- Visited Wishard Medical Center (Indianapolis, IN) in the calendar year 2000 and had a medical record available for query in the Regenstrief Medical Record System
- Simultaneous measured height and weight available in the medical record
- Race information available in the medical record
- Resident of Marion, County, Indiana.
- Age less than four years old or older than 18 years old
- Did not reside in Marion, County, Indiana in the calendar year 2000
- Could not query a medical record in the Regenstrief Medical Record System
- Did not have simultaneous measured height and weight in the medical record
- Did not have race information recorded.
Medical records queried through the Regenstrief Medical Record System to identify all children between the ages of four and 18 years seem at the Wishard medical Center in Indianapolis, IN during the calendar year 2000.
Implied in measurements
Univariate analysis performed on individual model variables for significance and overall model performance.
Timing of Measurements
A retrospective review of eligible participants' medical records was performed to determine age, race, gender, height, weight, BMI and demographic information. Spatial analysis was performed using address data obtained from the participants' medical records through a geocoding process.
BMI (calculated from measured height and weight)
- Proximity to the nearest public play space (measured in meters).
- Initial N: 2,496
- 1,015 males
- 1,481 females
- Attrition (final N): 2,496
- Age: Four to 18 years
- 1,475 Black
- 877 White
- 144 other
- Other relevant demographics: Authors report a high representation of children insured through government assistance programs such as Medicaid
- 1,521 children had a BMI in the normal range
- 470 had a BMI in the overweight range
- 505 had a BMI in the obese range
- Location: Indianapolis, IN.
There were no statistically significant differences between normal, overweight and obese children in terms of their straight-line proximity to public play space. In 505 obese children the mean distance was 567±450 meters. In 1991 non-obese children, the mean distance was 571±478 meters.
In general, with increasing age, the proportion of children falling into the overweight and obese categories increased. The mean age for 1,521 normal weight children was 14.51±1.99 years. The mean age for 470 overweight children was 14.84±2.04 years. The mean age for 505 obese children was 15.20±1.94 years.
- Authors are designing (at time of publication) a multivariate model of environmental predictors of childhood obesity
- Preliminary analysis show that markers of low socioeconomic status at the census tract level correlate with both overweight and obese outcomes in this study population
- The population reported in this paper has an over-representation of African-Americans, Latinos and patients receiving Medicaid. This bias may be advantageous given that several minority populations are disproportionately affected by obesity.
- This paper is a preliminary report of a conceptual model of environmental and social factors that may predict childhood obesity. Individual model variables are reported here with univariate analysis. Future work (at the time of publication) was planned to incorporate significant variables into a logistic regression model.
- The N of 2,496 included all children in the study with BMI data. Table 4 reported an N of 4,999. This table reported all children in the medical record database with an ICD-9 code for asthma in addition to the 2,496 children with available BMI data. This table is included to show racial discrepancies in terms of proximity to public play space in a larger sample of the same pediatric population.
Quality Criteria Checklist: Primary Research
|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)||Yes|
|2.||Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?||Yes|
|3.||Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?||Yes|
|4.||Is the intervention or procedure feasible? (NA for some epidemiological studies)||Yes|
|1.||Was the research question clearly stated?||Yes|
|1.1.||Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?||Yes|
|1.2.||Was (were) the outcome(s) [dependent variable(s)] clearly indicated?||Yes|
|1.3.||Were the target population and setting specified?||Yes|
|2.||Was the selection of study subjects/patients free from bias?||No|
|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?||Yes|
|2.2.||Were criteria applied equally to all study groups?||Yes|
|2.3.||Were health, demographics, and other characteristics of subjects described?||Yes|
|2.4.||Were the subjects/patients a representative sample of the relevant population?||No|
|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)||Yes|
|3.2.||Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?||Yes|
|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?||Yes|
|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.)||Yes|
|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?||Yes|
|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?||Yes|
|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.)||Yes|
|5.3.||In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?||Yes|
|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?||Yes|
|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?||Yes|
|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?||Yes|
|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?||Yes|
|7.2.||Were nutrition measures appropriate to question and outcomes of concern?||Yes|
|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?||Yes|
|7.5.||Was the measurement of effect at an appropriate level of precision?||Yes|
|7.6.||Were other factors accounted for (measured) that could affect outcomes?||No|
|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?||No|
|8.1.||Were statistical analyses adequately described and the results reported appropriately?||Yes|
|8.2.||Were correct statistical tests used and assumptions of test not violated?||Yes|
|8.3.||Were statistics reported with levels of significance and/or confidence intervals?||Yes|
|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)?||No|
|8.6.||Was clinical significance as well as statistical significance reported?||Yes|
|8.7.||If negative findings, was a power calculation reported to address type 2 error?||No|
|9.||Are conclusions supported by results with biases and limitations taken into consideration?||Yes|
|9.1.||Is there a discussion of findings?||Yes|
|9.2.||Are biases and study limitations identified and discussed?||Yes|
|10.||Is bias due to study's funding or sponsorship unlikely?||Yes|
|10.1.||Were sources of funding and investigators' affiliations described?||No|
|10.2.||Was the study free from apparent conflict of interest?||Yes|