PWM: Eating Behaviors of Children (2006)
Alaimo K, Olson CM, Frongillo EA Jr. Low family income and food insufficiency in relation to overweight in US children. Arch Pediatr Adolesc Med 2001; 155:1161-1167.
Examine the following questions:
- Does an increased prevalence of food insufficiency and overweight coexist in the population of US children living in families with low income?
- Is food insufficiency independently associated with overweight, controlling for known confounders?
Data from the Third National Health and Nutrition Examination Survey. Responses were included if
- respondent answered "yes" to question asking whether their family sometimes or often did not get enough food to eat
- children whose race was listed as "other"
- pregnant teenage girls
- girls who had previously given birth
Defining Food Insufficiency
The authors distinguish between different levels of hunger, "food insecurity" and "food insufficiency". Although the categories are not entirely clear (multiple definitions are used in the literature), the authors distinguish among three general levels of hunger:
- food insecurity: if members are habitually concerned about their food situation or if an adult in the family occasionally goes without food (eg, skips meals)
- food insufficiency (similar to "moderately hungry): roughly, an adult in the family goes without food or a child is cutting the size of his or her meals or "not eating enough"
- severe hunger: an adult in the family goes without food for a whole day or a child in the family ever goes without food (skips meals)
The authors focus on food insufficiency and this is operationalized in terms of a response to a question in the NHANES III: "sometimes" or "often" answer to question of whether the family did not get enough food to eat.
Weighted sample to take into account over sampling; separate analyses by ethnic group; multivariate logistic regression.
The poverty/income ratio variable was entered as a continuous variable.
BMI (measured height, weight): ‘risk of overweight’ = BMI > 85th percentile
- Food insufficiency (based on if responded to single question: “sometimes” or “often” did not get enough food to eat)
Confounding Figure 1 shows list of control variables, including income (get this figure)
Ethnicity and age (due to separate analyses)
- 5200 males and females; 2-7 years
- 3996 males and females; 8-16 years
Ethnicity: White, black (all non-Hispanic) & Mexican American
SES: Mixed SES
Are food insufficiency, overweight, and low income related?
The authors report that these three characteristics tend to "coexist" only among older (8-16 year-old) non-Hispanic white children.
In other words, only among slightly older white children is overweight associated with low-income and food insufficiency.
Is food insufficiency associated with overweight when confounding variables are taken into account?
No differences in overweight by food insufficiency status after adjusting for confounding variables, except:
2-7 year old food-insufficient girls were 1.6 times less likely to be overweight
white 8-16 year old food-insufficient girls were 3.5 times more likely to be overweight than food-sufficient girls (p < 0.10).
Further research to evaluate whether food insecurity causes overweight in American children requires longitudinal quantitative and in depth qualitative methods.
- food insufficiency measure may be closer to the concept of “hunger” than mild-moderate food insecurity; did not assess fluctuations in food availability; based on single question to caretakers
- food insufficiency measure applies to household, not necessarily to children
- p = 0.10 not typically considered significant!
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)||N/A|
|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)||N/A|
|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?||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?||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?||Yes|
|3.||Were study groups comparable?||N/A|
|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?||No|
|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?||No|
|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?||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?||Yes|
|7.7.||Were the measurements conducted consistently across groups?||Yes|
|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?||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)?||Yes|
|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?||Yes|
|10.2.||Was the study free from apparent conflict of interest?||Yes|