Protocol - Current Age
The interviewer asks the respondent for his or her date of birth in MM/DD/YYYY format. If the respondent does not know his or her date of birth, the interviewer asks an alternative question to determine his or her age. NOTE: The current age of the respondent can be calculated, given the date of the interview.
The question may be asked of a proxy. Proxies are others in the household who can answer on behalf of the index person (e.g., parent, spouse) if the index person is too young, incapacitated, deceased, or cannot be located.
What is your birthdate? MM/DD/YYYY;
9[ ]Don’t Know [ask follow-up question];
[Follow-up question if "don’t know":] About how old are you? AGE _______;
999[ ]Don’t Know
Personnel and Training Required
The interviewer must be trained to conduct personal interviews with individuals from the general population. The interviewer must be trained and found to be competent (i.e., tested by an expert) at the completion of personal interviews.* The interviewer should be trained to prompt respondents further if a "don’t know" response is provided.
* There are multiple modes to administer this question (e.g., paper-and-pencil and computer-assisted interviews).
While the source instrument was developed to be administered by computer, the PhenX Working Group acknowledges these questions can be administered in a noncomputerized format (i.e., paper-and-pencil instrument). Computer software is necessary to develop computer-assisted instruments. The interviewer will require a laptop computer or handheld computer to administer a computer-assisted questionnaire.
|Specialized requirements for biospecimen collection||No|
|Average time of greater than 15 minutes in an unaffected individual||No|
Mode of Administration
Infant, Toddler, Child, Adolescent, Adult, Senior, Pregnancy
Age is a primary predictor of disease and the most important potential confounder in epidemiologic studies.
Age at date of interview or exam can be compared to age in future follow-up interviews or exams for longitudinal research purposes.
Vetted against several other current age questions, the National Health and Nutrition Examination Survey (NHANES) question was selected because it included the date of birth (DOB) and a follow-up question to collect current age if the respondent did not know his or her DOB.
Chinese, English, Spanish
|caDSR Common Data Elements (CDE)||Birth Date||2201154||CDE Browser|
|Logical Observation Identifiers Names and Codes (LOINC)||Current age proto||62293-6||LOINC|
Age at onset, present age
Process and Review
The Expert Review Panel #2 (ERP 2) reviewed the measures in the Demographics, Environmental Exposures, and Social Environments domains.
Guidance from ERP 2 includes:
• No significant changes to measure
Back-compatible: no changes to Data Dictionary
Previous version in Toolkit archive (link)
Protocol Name from Source
National Health and Nutrition Examination Survey (NHANES), 2005-2006
National Center for Health Statistics. National Health and Nutrition Examination Survey (NHANES), Screener Module 1, 2005–2006. Question numbers: SCQ.290 and SCQ.292.
Public Population Project in Genomics (P3G) Data Shaper.
|Variable Name||Variable ID||Variable Description||dbGaP Mapping|
|PX010101020000||About how old are you?||Variable Mapping|
|PX010101020100||About how old are you?||N/A|
|PX010101010400||What is your birthdate?||N/A|
|PX010101010200||What is your birthdate? Day||Variable Mapping|
|PX010101010100||What is your birthdate? Month||Variable Mapping|
|PX010101010300||What is your birthdate? Year||Variable Mapping|
February 6, 2009
Question to determine the respondent’s current age using his or her date of birth.
Current age is a critical component of a respondent’s demographic background. Date of birth (DOB)/current age is essential to medical research because it captures the age at the time of the clinical visit or diagnosis. Age is related to nearly all diseases and conditions and is the strongest potential confounder of other effects on these processes. Current age is often used to stratify respondents for more valid comparison (e.g., obesity of males aged 40-45 in Mississippi).
current age, Demographics, National Center for Health Statistics, NCHS, Centers for Disease Control and Prevention, CDC, age, date of birth, DOB, National Health and Nutrition Examination Survey, NHANES, Demographics-Populations with HD
|Protocol ID||Protocol Name|
- Joint Effects of PON1 Polymorphisms and Vegetable Intake on Ischemic Stroke: A Family-Based Case Control Study
- Electronic Medical Records and Genomics (eMERGE) Network
- Perceived Discrimination as a Risk Factor for Use of Emerging Tobacco Products: More Similarities Than Differences Across Demographic Groups and Attributions for Discrimination
- Pennsylvania Adult Smoking Study
- Personalized Medicine Research Project (PMRP) (eMERGE I)