Sensitivity and Specificity of Obesity Diagnosis in Pediatric Ambulatory Care in the United States

1Boston Medical Center/Boston Children's Hospital, Boston, MA, USA.
Clinical Pediatrics (Impact Factor: 1.26). 05/2013; 52(9). DOI: 10.1177/0009922813488648
Source: PubMed

ABSTRACT Objective. We examined the sensitivity and specificity of an obesity diagnosis in a nationally representative sample of pediatric outpatient visits. Methods. We used the 2005 to 2009 National Ambulatory Medical Care and National Hospital Ambulatory Medical Care surveys. We included visits with children 2 to 18 years, yielding a sample of 48 145 database visits. We determined 3 methods of identifying obesity: documented body mass index (BMI) ≥95th percentile; International Classification of Diseases, Ninth Revision (ICD-9) code; and positive answer to the question, "Does the patient now have obesity?" Using BMI as the gold standard, we calculated the sensitivity and specificity of a clinical obesity diagnosis. Results. Among the 19.5% of children who were obese by BMI, 7.0% had an ICD-9 code and 15.2% had a positive response to questioning. The sensitivity of an obesity diagnosis was 15.4%, and the specificity was 99.2%. Conclusions. The sensitivity of the obesity diagnosis in pediatric ambulatory visits is low. Efforts are needed to increase identification of obese children.

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