U.S. Department of Health and Human Services Office of Disease Prevention and Health Promotion

Reduce the proportion of adults who don't know they have prediabetes — D‑02 Data Methodology and Measurement

On this page:  About the National Data  |  Methodology

About the National Data

Data

Data Source:  National Health and Nutrition Examination Survey (NHANES), CDC/NCHS

Baseline: 38.0 percent of adults aged 18 years and over, who had not been diagnosed with prediabetes or diabetes, had undiagnosed prediabetes in 2013-16

Target: 33.2 percent

Numerator
Number of adults aged 18 years and over who have undiagnosed prediabetes (a fasting blood glucose level between 100 and 126 mg/dl or an HbA1c between 5.7 and 6.5).
Denominator
Number of adults aged 18 years and over without diagnosed or undiagnosed diabetes or diagnosed prediabetes (i.e. adults aged 18 years and over who have A1c less than 6.5 or fasting plasma glucose less than 126 and do not report being diagnosed with prediabetes or diabetes by a health care professional).
Target-setting method
Percentage point improvement
Target-setting method details
Percentage point improvement from the baseline using Cohen's h effect size of 0.10.
1
Target-setting method justification
Trend data were not available for this objective. A percentage point improvement was calculated using Cohen's h effect size of 0.1. This method was used because it was a statistically significant improvement from the baseline.

Methodology

Questions used to obtain the national baseline data

(For additional information, please visit the data source page linked above.)

From the 2013-2016 National Health and Nutrition Examination Survey:

Denominator:
{Have you/Has SP} ever been told by a doctor or other health professional that {you have/SP has} any of the following: prediabetes, impaired fasting glucose, impaired glucose tolerance, borderline diabetes or that {your/her/his} blood sugar is higher than normal but not high enough to be called diabetes or sugar diabetes?
  1. Yes
  2. No
  3. Refused
  4. Don't know/Not stated
Other than during pregnancy, {have you/has SP}/{Have you/Has SP}} ever been told by a doctor or other health professional that {you have/{he/she/SP} has} diabetes or sugar diabetes?
  1. Yes
  2. No
  3. Borderline or pre-diabetes
  4. Refused
  5. Don't know/Not stated

Methodology notes

The population at high risk for developing diabetes is defined as persons who have prediabetes—this includes persons who do not have doctor diagnosed diabetes (do not respond yes to ever being diagnosed with diabetes or sugar diabetes) and have either a fasting blood glucose level of greater than or equal to 100 or less than 126 mg/dl or have an A1c level of =5.7% to <6.5%.
  Persons are considered not to have diagnosed pre-diabetes if they respond "no" to the question "have you ever been told by a doctor you have pre-diabetes" and "no" to the question "have you ever been told by a doctor that you have diabetes." Women who report that the only time they have been diagnosed with diabetes was during pregnancy (gestational diabetes) are also considered not to have diagnosed diabetes.   Data for HbA1c are available for the whole sample, but data for fasting glucose are only measured for the morning examination session. For this analysis the cohort examined is restricted to persons in the AM exam session only. Backward calibration equations were used to account for changes in plasma glucose laboratory procedures over time. This indicator uses age-adjustment groups:   Total: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+.

Age-adjustment notes

This Indicator uses Age-Adjustment Groups:

  • Total: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Sex: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Race/Ethnicity: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Educational Attainment: 25-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Family Income (percent poverty guidelines): 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Health Insurance Status: 18-29, 30-39, 40-49, 50-59, 60-64
  • Marital Status: 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Geographic Location: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Country of Birth: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Veteran Status: 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Activity Limitations: 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Sexual Orientation: 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+
  • Obesity Status: 20-49, 50-59, 60-69, 70-79, 80+

1. Effect size h=0.1 was chosen to correspond with 10% improvement from a baseline of 50%.