Weight Perception Measured by Verbal Descriptions and Visual Descriptions: Which Measurement Correlates with Weight Loss Intentions among Female Nursing Students?

Abstract

Background: Young females tend to overestimate their weight status, which might induce unhealthy weight loss intentions and behaviours. This study aimed to examine weight perception measured by visual and verbal descriptions and its correlation with weight loss intentions among female nursing students. Methods: A cross-sectional survey was conducted among 600 female nursing students from four medical colleges in Shanghai, China. The participants rated perceptions of their weight by selecting a silhouette from the female Photographic Figure Rating Scale (PFRS) and one of the following verbal descriptions: “very underweight”, “slightly underweight”, “normal”, “overweight” or “obese”. Weight loss intentions were measured using the question “How often do you want to lose weight?”. Body mass index (BMI) was calculated from self-reported height and weight. Data were analysed using univariate and ordinal logistic regression analyses. Results: The accuracy of weight perceptions measured by verbal descriptions and visual descriptions was 44.50% and 55%, respectively. In females with underweight BMI (n = 135), 88.15% and 49.63% accurately classified their weight using visual descriptions and verbal descriptions, respectively. These females were more likely to overestimate (53.83% vs. 14.50%) and less likely to underestimate (1.67% vs. 30.50%) their weight when using verbal descriptions than when using visual descriptions. For verbal descriptions, weight overestimation was associated with weight loss intentions (odds ratio, 1.80; 95% confidence interval, 1.25–2.60). However, for visual descriptions, the two variables were not associated. Conclusions: A mismatch occurred between weight perceptions measured by the two methods and BMI status among female nursing students. Compared with verbal descriptions, visual descriptions had higher weight perception accuracy. However, weight overestimation measured by verbal descriptions was more likely to be associated with stronger intentions to lose weight than that of visual descriptions. These findings suggest that methodological discrepancies should be taken into account when measuring weight perception in future studies.