Tests of trend between disease outcomes and ordinal covariates discretized from underlying continuous variables: simulation studies and applications to NHANES 2007–2008

Table 1 Description of NHANES Data by BMI Class

BMI Class	WHO Defined Lower Limit (kg/m²)	WHO Defined Upper Limit (kg/m²)	Number of Individuals	Unweighted Percent of Sample	WHO Defined Median (kg/m²)	Sample Median BMI (kg/m²)
Underweight	12	18.5	93	1.7	17	17.8
Normal Weight	18.5	25	1513	27.3	23	22.7
Overweight	25	30	1919	34.6	28	27.5
Obese	30	70	2026	36.5	35	34.0

ISSN: 1471-2288