Parents of children who are overweight often fail to accurately identify their child’s weight status. Although these misperceptions are presumed to be a major public health concern, little research has examined whether parental perceptions of child weight status are protective against weight gain during childhood. Our objective was to examine whether parental perceptions of child weight status are associated with weight gain across childhood.
Data from the Longitudinal Study of Australian Children were used to assess parental perceptions of child weight status and to examine changes in researcher measured child BMI z scores across childhood, from 4 to 13 years old. Participants included 3557 Australian children and their parents.
Children whose parents perceived their weight as being “overweight,” as opposed to “about the right weight,” gained more weight (increase in BMI z score) from baseline to follow-up in all analyses. This finding did not depend on the actual weight of the child; the association between perceiving one’s child as being overweight and future weight gain was similar among children whose parents accurately and inaccurately believed their child was overweight.
Contrary to popular belief, parental identification of child overweight is not protective against further weight gain. Rather, it is associated with more weight gain across childhood. Further research is needed to understand how parental perceptions of child weight may counterintuitively contribute to obesity.
Comments
Response to Zhang and colleagues
We enjoyed reading Zhang and colleagues comment on our recent study in which we examined the relationship between parental perceptions of child weight status and weight gain (1). In our initial analysis we examined the association between parental perception of child overweight and child weight gain. We found that parental perception of child overweight was associated with increased child weight gain. We also tested whether this association was moderated by child weight at baseline by examining interaction terms between parental perception of child overweight and child weight at baseline. However, in all of the models we run we found no statistical evidence for moderation and we interpreted this finding as being evidence that the association between parental perception of child overweight and weight gain is not dependent on a child’s actual weight.
In their comment (2), Zhang and colleagues suggested that additional analyses may provide more insight into the overall results we reported and resolve some concerns they had surrounding the issue of residual confounding in our reported analyses. In particular, the authors suggested that stratifying our analyses and examining the association between parental perception of child overweight and subsequent weight gain in overweight and obese children (as opposed to also including normal weight children in the analyses) would be informative. We did not consider reporting this analysis in our study because of a lack of statistical evidence from our moderation analyses. However, we appreciate Zhang and colleagues’ suggestion and now report this analysis below.
We re-ran our main analysis strategy examining whether parental perception of child weight status at age 4/5 years predict weight gain from age 4/5 years to 12/13 years only in overweight and obese children (n=703). We combined data from overweight and obese children for this analysis because of sample size constraints. Among overweight and obese children parental perception of child overweight was associated with increased child weight gain (b=.135, SE=.071, p=.058), although just short of conventional statistical significance. We also conducted the same analysis in the sampling period in which we had the largest number of children in our study (weight gain from age 4/5 years to 6/7 years) to test the association between parental perception of child overweight and child weight gain. In this analysis we again found that parental perception of child overweight was associated with increased child weight gain in overweight/obese children (n = 833, b=.192, SE=.052, p<.001). It is important to note that these findings are also consistent with a study we cited in our original article (3), which showed that among overweight and obese Dutch children accurate parental perception of child overweight was associated with increased weight gain.
We would like to thank Zhang and colleagues for their interest in our work. We suggest that parental perception of child overweight appears to be associated with increased child weight gain in both normal weight and overweight/obese children. Further research to explain this association will now be valuable.
RE: Proper awareness, but wrong action, What is missing?
The study by Robinson and Sutin suggests that “Contrary to popular belief, parental identification of child overweight is not protective against further weight gain”(1) We were approached by the press to address the potential contradictions between Robinson’s study and previous reports, including ours(2), and possible confusion to the public. We failed to see any conflicts between the Robinson’s study and ours. Instead, we found consistency between this new study and ours.
Correctly recognizing when a child has a weight issue is one thing, taking the appropriate action to correct it is another. The 3As framework, i.e. Awareness, Acceptance and Action, for promoting personal growth postulates that being aware is the important first step, but acceptance is the crucial step after elevating awareness necessary prior to taking action(3). Acceptance involves full acknowledgment of the true nature of an issue. In this case, we should remove the stigma attached to obesity, and parents should be persuaded that childhood overweight/obesity is preventable and reversible, otherwise, serious medical consequences are certain if not corrected in a timely manner. Instead of creating contradictions, Robinson’s study, if confirmed by additional studies, brings another serious issue to the table. That is, in addition to the declining awareness demonstrated in our study(2), the translation from awareness to action is also not efficient, and even worse; the translation is going in the wrong direction.
Robinson’s study(1) is an important contribution to the ongoing efforts to explore the effective strategies to curb the childhood obesity epidemic. We also believe that the study, if analyzed more appropriately, is able to provide more insight into the puzzling results reported. The study has a decent number of overweight/obese children (n=703) at the baseline survey, offering a great opportunity to see specifically the effect of parental perceptions on the trajectory of body weight among overweight and obese children. Parentally-perceived overweight status may have fundamentally different meanings for healthy weight, overweight and obese children. More than 10% of parentally perceived overweight children were children with healthy weight. Unfortunately, the authors lumped all participants together, fully relying on the interaction terms to statistically discern the delicately psychological and behavioral impact of parental perception. Assessing “interaction terms between parental perceptions of weight status and baseline child BMI z score” may end with a substantial amount of residual confounding. Stratified regression for overweight and obese children, if sample size allows, might be a more reliable way to remove confounding, describe modifying effects and generate more specific conclusions(4); It’s true that stratifying a study population by BMI-z scores may reduce variations, but simply assuming BMI-z score linearly predicts future body weight at selected time points is more problematic.
Apparently, there is a misinterpretation regarding correcting weight misperception, not only among the general public, but also the scientific literature. Correcting weight misperception is more than perfectly matching the image in the mirror and the number on the scale. It is about correcting weight stigma and understanding the preventability and reversibility of childhood obesity and the associated health risks.
Reference List
1. Robinson E, Sutin AR. Parental Perception of Weight Status and Weight Gain Across Childhoodd behaviors. Pediatrics 2016; 137(5):e20153957.
2. Hansen AR, Duncan DT, Tarasenko YN, Yan F, Zhang J. Generational shift in parental perceptions of overweight among school-aged children. Pediatrics 2014; 134(3):481-488.
3. Cardaciotto L, Herbert JD, Forman EM, Moitra E, Farrow V. The assessment of present-moment awareness and acceptance: the Philadelphia Mindfulness Scale. Assessment 2008; 15(2):204-223.
4. Greenland S, Rothman KJ. Introduction to Stratified Analysis. In: Rothman KJ, Lash TL, Greeland S, eds. Modern Epidemiology. Third Edition (Revised) ed. Lippincott, Williams, & Wilkins, 2012, pp. 258-282.