National Long-Term Care Survey

NLTCS Codebook Overview


Non-questionnaire Survey Variables

Code book documentation of the non-questionnaire survey variables appears immediately after the Caregiver Survey Code book.  Non-questionnaire variables come from several sources and may be referenced as appropriate within the questionnaire and code books.  The non-questionnaire survey variables document case level information used in sample selection such as the sample person's date of birth and sex.   Date of birth and sex are included on the CAPI input file as dependent data used to confirm the identity of the respondent during the interview.  These type of variables also document information associated with the results of sample selection such as a sample person's cohort assignment and base weight.  In addition, the non-questionnaire variables can include information derived from data collected in the CAPI instrument, but not defined in the questionnaire code books. Finally, non-questionnaire variables include information resulting from post-data collection processing such as the assignment of the screener cross-sectional weight.


Sample Person: A person age 65 years of age or older who was selected from the

CMS list of eligible Medicare beneficiaries.


Proxy: If the sample person is unavailable or unable to answer a person who is knowledgable about the sample person's health conditions and physical activities may be used. The proxy must be at least 15 years old. A list of eligible proxies appears below:

Spouse/spousal equivalent




Other relative living in household

Other relative not living in household

Legal guardian

Proxy designated by sample person/family member/legal guardian

If the sample person is deaf or does not speak English and an interpreter is available during the interview, the interview is considered to be a self-interview. However, if the person answers for the sample person without first interpreting the question for him/her, that person is considered a proxy. The interview is a proxy interview. You may also use a proxy for part of the interview if the sample person indicates that someone else can answer certain items more accurately.

Who can be a Proxy?

Ideally, a proxy should be a household member 15 years of age or older who knows about the care obtained or needed by the sample person. (Do not interview a teenager, however, except as a last resort.) The proxy may or may not be related to the sample person. The key requirement is that the proxy know about the sample person's regular care.

When to interview a Proxy.

Proxies should be interviewed when the sample person is unavailable for interview because he/she:

Is temporarily absent during the survey period

Is unable to be interviewed due to a physical or mental disability

Does not speak sufficient English.

When the sample person lives by himself/herself and cannot be interviewed because he/she is deaf or cannot speak understandably, you should try to interview a non-household member over the age of 15 who knows he/she does not speak English.) You may have to make inquiries to find the name, address, or telephone number of a relative if the sample person lives alone.


Screener Codebook

Control Card Codebook

Community Codebook

Institutional Codebook

Caregiver Codebook

Non-Questionnaire Variables Codebook


Currently, an online codebook is available for 1999 only. The 1999 codebook describes the data in the 1999 Final Version 1.0 data release. There are several points to make. The values for all responses are coded in alphanumeric format. This was done to accommodate permissible responses such as 'D' for 'Don't know' and 'R' for 'Refused.' This coding has some unfortunate side effects. Responses were coded with or without leading zeros ('4' and '04'). A frequency done on such a variable would have a count for '4' and a separate one for '04.' Also, when the data are read in one of the popular analysis packages such as SAS, the researcher is faced with the dilemma of reading it as numeric data, in which case 'Ds' and 'Rs' are interpreted as missing, or reading it as alphanumeric and dealing with the conversion internally.

The 1999 Final Version 1.0 data release is a single physical file incorporating the variables from all questionnaires except Venipuncture, Buccal, and Next-of-Kin. These reside in separate files. Some variables are common to the three core questionnaires: Screener, Community Detail, and Institutional Detail. An example is the variable OUTCOME, which is generated by the CAPI program to record the outcome of the interview. In 1999, this single variable was used to record the outcome for all three questionnaires. Consequently, the value recorded in the data file is for the last questionnaire administered only.

There are significant performance issues that force segmenting the codebook into separate files, each with its own link. This version of the codebook has the codebook segmented according to questionnaires. A segmentation based on some other feature such as alphabetic lists of variables would be preferable and will be done in future versions.

Lookup Variables by Name

[ A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z ]

Lookup Variables by Survey Section


Section A: Amounts and Kinds of Help   (Printer Friendly Versions: .txt  .pdf)

Section B: Help from Others   (Printer Friendly Versions: .txt  .pdf)

Section C: Caregiver's Experience   (Printer Friendly Versions: .txt  .pdf)

Section D: Caregiver's Living Situation   (Printer Friendly Versions: .txt  .pdf)

Section E: Caregiver's Work Situation   (Printer Friendly Versions: .txt  .pdf)

Section F: General Information on Caregiver   (Printer Friendly Versions: .txt  .pdf)


Section A: Functional Status

Section A, Part 1: Condition List   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 2: Activities of Daily Living   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 3: Instrumental Activities of Daily Living   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 4: Helpers Section   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 5: Range of Motion and Impairment   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 6: Nutrition and Social Activities   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 7: Alcohol Consumption and Smoking   (Printer Friendly Versions: .txt  .pdf)

Section A, Part 8: Cognitive Functioning   (Printer Friendly Versions: .txt  .pdf)

Section B: Other Functioning   (Printer Friendly Versions: .txt  .pdf)

Section C: Housing and Neighborhood Characteristics   (Printer Friendly Versions: .txt  .pdf)

Section D: Health Insurance   (Printer Friendly Versions: .txt  .pdf)

Section E: Medical Providers and Prescription Medicines   (Printer Friendly Versions: .txt  .pdf)

Section F: Military Service, Ethnicity, Income and Assets   (Printer Friendly Versions: .txt  .pdf)

Section G: Field Observations   (Printer Friendly Versions: .txt  .pdf)

Control Card

All Sections   (Printer Friendly Versions: .txt  .pdf)


Section ADL: Activities of Daily Living   (Printer Friendly Versions: .txt  .pdf)

Section AMN: Admissions, Who Pays, and Health Insurance   (Printer Friendly Versions: .txt  .pdf)

Section BED: Certified Beds   (Printer Friendly Versions: .txt  .pdf)

Section FAM: Family   (Printer Friendly Versions: .txt  .pdf)

Section IAA: Income and Assets   (Printer Friendly Versions: .txt  .pdf)

Section MNTI: Cognitive Functioning   (Printer Friendly Versions: .txt  .pdf)


All Sections   (Printer Friendly Versions: .txt  .pdf)

Non Survey Variables

All Sections   (Printer Friendly Versions: .txt  .pdf)