1995 NATIONAL HEALTH INTERVIEW SURVEY 04/15/2008 PUBLIC USE DATA RELEASE * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * WARNING - DATA USE RESTRICTIONS! Read Carefully before Using The Public Health Service Act (Section 308 (d)) provides that the data collected by the National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention (CDC), may be used only for the purpose of health statistical reporting and analysis. Any effort to determine the identity of any reported case is prohibited by this law. NCHS does all it can to assure that the identity of data subjects cannot be disclosed. All direct identifiers, as well as any characteristics that might lead to identification, are omitted from the data files. Any intentional identification or disclosure of a person or establishment violates the assurances of confidentiality given to the providers of the information. Therefore, users will: 1. Use the data in these data files for statistical reporting and analysis only. 2. Make no use of the identity of any person or establishment discovered inadvertently and advise the Director, NCHS, of any such discovery (301-458-4000). 3. Not link these data files with individually identifiable data from other NCHS or non-NCHS data files. By using these data, you signify your agreement to comply with the above-stated statutorily based requirements. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * INTRODUCTION The National Health Interview Survey (NHIS) is conducted annually by the National Center for Health Statistics, Centers for Disease Control and Prevention (CDC). The NHIS administers face-to-face interviews in a nationally representative sample of households. Each week a probability sample of the civilian non- institutionalized population of the United States is interviewed by personnel of the U.S. Bureau of the Census. Information is obtained about the health and other characteristics of each member of the household. The NHIS includes a basic questionnaire that remains the same each year plus one or more additional questionnaires that change periodically. In 1995 the additional questionnaires were: Disability, Access to Care, AIDS Knowledge and Attitudes, Family Resources (Income), Health Insurance, Immunization, and Year 2000 Objectives. NOTES TO USERS Disability questionnaires were administered in both 1994 and 1995. Five of the 1995 questionnaires asked questions about each member of every sample family (basic questionnaire or "Core," Disability, Access to Care, Family Resources, and Health Insurance), two asked questions about a randomly selected adult member of sample families (AIDS Knowledge and Attitudes, Year 2000 Objectives), and one asked questions about preschool aged children (Immunization). Information about the same person is found on all files. Each file can be linked by using the unique identification number assigned to each person which is found in locations 5-16 on each file. Both 1994 and 1995 NHIS included the Phase 1 of the Disability supplement (NHIS-D). NHIS-D included two household interviews: in Phase 1 all members of sample families were screened for any indication of disability; in Phase 2 persons with any indication of disability were followed-up for additional information. Phase 1 interviews were conducted in calendar years 1994 and 1995; Phase 2 interviews were conducted 6-8 months after the Phase 1 interviews and were completed in early 1997. The data from the 1995 Phase 1 interviews and their Phase 2 follow-up interviews are included in the 1994-1995 NHIS files. Users are advised to subscribe to the NHIS Listserv to receive notice of any corrections/updates. For information about joining the Listserv, see the CONTACT INFORMATION section at the bottom of this document. 1995 NHIS FILES AND DOCUMENTATION The 1995 NHIS files and related documentation have been previously distributed via various formats -- magnetic tape, ASCII CDs, SETS CDs, etc. The files listed below comprise the 1995 National Health Interview Survey (NHIS) public use data release as found on the Internet. A copy of this file (README.TXT) is located in ASCII format at the following ftp location: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Program_Code/NHIS/1995 1995 NHIS DATA FILES Five 1995 NHIS files are referred to as "core" files because they were administered each year (through 1996) without major modification. The five core files are Household, Person, Condition, Doctor Visit, and Hospital. The 1995 NHIS data have been divided into sixteen data files, consisting of the five core files and eleven supplemental files. In addition, in 2008, a file containing additional imputation flags for the 1995 Family Resources supplement was released. For ease of transmission, each of the 1995 NHIS data files has been converted into a self-extracting compressed format. To load and expand a compressed file into an ASCII file, perform the following steps: Download a compressed file onto your hard drive into an appropriate directory (folder). For example: Copy the data file HOUSEHLD.EXE into a directory called NHIS1995. To do this, create a directory on your C: drive called NHIS1995. Then, using your browser, go to the FTP site containing the 1995 NHIS data files (see address at end of this section). Right click on the HOUSEHLD.EXE file. Depending on your browser, select Save Link As... or Save Target As... Type c:\nhis1995\HOUSEHLD.EXE in the box labeled File Name and hit Enter. To then extract HOUSEHLD.EXE into the ASCII file HOUSEHLD.DAT, go to the directory NHIS1995 and do the following: - From DOS - in the c:\nhis1995 directory, type HOUSEHLD and hit Enter - From Windows - Double-click on HOUSEHLD.EXE or Click the Start Button, Click Run, enter c:\nhis1995\HOUSEHLD.EXE and hit Enter. The ASCII file HOUSEHLD.DAT will be generated which can then be used for processing by PC statistical software packages which utilize ASCII formatted input, or transferred to another computer for processing. NOTE: The 1995 NHIS files are large in size. Please use caution and check your disk drive capacity before extracting. 1995 NHIS DATA FILES RECORD NHIS FILE TYPE FILE NAME LENGTH # RECS ------------------- ------------ ------ ------- HOUSEHOLD HOUSEHLD.DAT 355 41,824 PERSON PERSONSX.DAT 355 102,467 CONDITION CONDITON.DAT 355 75,701 DOCTOR VISIT DRVISITX.DAT 355 22,721 HOSPITAL HOSPITAL.DAT 355 10,120 ACCESS TO CARE ACCESSXX.DAT 440 102,467 AIDS K AND A AIDSKNOW.DAT 543 16,848 DISABILITY COND DIS1COND.DAT 473 37,409 DISABILITY PERS DIS1PERS.DAT 1660 95,091 DISAB2 ADULT DFSADULT.DAT 3400 9,691 DISAB2 CHILD DFSCHILD.DAT 1860 2,687 DISAB2 OUTCOME OUTCOMEX.DAT 18 95,091 FAMILY RESOURCE FAMLYRES.DAT 655 102,467 HEALTH INSURANC HEALTHIN.DAT 560 102,467 IMMUNIZATION IMMUNIZE.DAT 620 7,287 YEAR 2000 OBJ YEAR2000.DAT 650 17,317 FAM RES - FLAGS FLGNEW95.DAT 105 102,467 Notes: The above data files are the unzipped files in ASCII format. See 1994 NHIS release for the 1994-1995 Disability Phase 2 Polio files. The 1995 NHIS data files are located at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Datasets/NHIS/1995 1995 NHIS FILE LAYOUTS (CODEBOOKS) There is a file layout (also called codebook or data dictionary) for with each data file. The file layouts are in PDF format and can be viewed with Adobe Acrobat software. The Adobe Acrobat Reader software can be downloaded from the Adobe Acrobat Web site at: http://www.adobe.com/products/acrobat/readstep2.html File File Name Description of Component Format NHISCORE.PDF Core* files layout Adobe PDF ACCESSXX.PDF Access to Care file layout Adobe PDF AIDSKNOW.PDF AIDS Knowledge and Attitudes file layout Adobe PDF DIS1COND.PDF Disability Phase 1 Condition file layout Adobe PDF DIS1PERS.PDF Disability Phase 1 Person file layout Adobe PDF DFSADULT.PDF Disability Phase 2 Adult file layout Adobe PDF DFSCHILD.PDF Disability Phase 2 Child file layout Adobe PDF OUTCOMEX.PDF Disability Phase 2 Outcome file layout Adobe PDF FAMLYRES.PDF Family Income file layout Adobe PDF HEALTHIN.PDF Health Insurance file layout Adobe PDF IMMUNIZE.PDF Immunization file layout Adobe PDF YEAR2000.PDF Year 2000 Objectives file layout Adobe PDF FREQ1995.PDF Fam. Res. - Added imp. flags Adobe PDF (frequencies) LAYOUT95.PDF Fam. Res. - Added imp. flags Adobe PDF (file layout) READMEFR.PDF Fam. Res. - Added imp. flags Adobe PDF (readme file) *Note: NHISCORE.PDF contains the file layouts for the following five core files: Household, Person, Condition, Doctor Visit, and Hospital. The 1995 NHIS data file layout documentation files are located at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/1995 1995 NHIS SAS INPUT STATEMENTS Sample SAS programs containing input statements have been provided for each data file. By using the ASCII data files (.DAT files) as input to these programs, SAS data files can be created. The SAS input statement programs are stored in ASCII format. File File Name Description of Component Format HOUSEHLD.SAS Household file SAS program ASCII PERSONSX.SAS Person file SAS program ASCII CONDITON.SAS Condition file SAS program ASCII DRVISITX.SAS Doctor Visit file SAS program ASCII HOSPITAL.SAS Hospital file SAS program ASCII ACCESSXX.SAS Access to Care SAS program ASCII AIDSKNOW.SAS AIDS Knowl. & Att. SAS program ASCII DIS1COND.SAS Disab. Ph. 1 Condition SAS pgm ASCII DIS1PERS.SAS Disab. Ph. 1 Person SAS pgm ASCII DFSADULT.SAS Disab. Ph. 2 Adult SAS pgm ASCII DFSCHILD.SAS Disab. Ph. 2 Child SAS pgm ASCII OUTCOMEX.SAS Disab. Ph. 2 Outcome SAS pgm ASCII FAMLYRES.SAS Family Income SAS program ASCII HEALTHIN.SAS Health Insurance SAS program ASCII IMMUNIZE.SAS Immunization SAS program ASCII YEAR2000.SAS Year 2000 Objectives SAS pgm ASCII FLGNEW95.SAS Fam. Res. - Added imp. flags ASCII The 1995 NHIS sample SAS input statement programs are located at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Program_Code/NHIS/1995 1995 NHIS SURVEY QUESTIONNAIRES and FLASHCARDS The 1995 NHIS questionnaires and flashcards can be found as an appendix to the 1995 Current Estimates publication which is on the internet at: http://www.cdc.gov/nchs/data/series/sr_10/sr10_199acc.pdf MISCELLANEOUS All information collected in the survey is from reports by responsible family members residing in the household. When possible, all adult family members participate in the interview. However, proxy responses are accepted for family members who are not at home and are required for all children and for family members who are physically or mentally incapable of responding for themselves. Although a considerable effort is made to ensure accurate reporting, the information from both proxy respondents and self-respondents may be inaccurate because the respondent is unaware of relevant information, has forgotten it, does not wish to reveal it to an interviewer, or does not understand the intended meaning of a question. Data from the special health topics (supplements) and core in 1995 were collected for 48 weeks. The first week of the year was used for interviewer training and the last three weeks of the year were missed due to a general government furlough. This resulted in a slightly smaller sample size. The interviewed sample for 1995 consisted of 39,239 households containing 102,467 persons. The total noninterview rate was 6.2 percent: 4.4 percent was the result of respondent refusal, and the remainder was primarily the result of failure to locate an eligible respondent at home after repeated calls. Fields on NHIS files that are used for matching between files are different beginning in 1995. The sample for the NHIS is redesigned every decade using population data from the most recent decennial census. A redesigned sample was implemented in 1995, so the sample design for 1995 is different from the sample designs in 1994 and earlier years of the NHIS. This new design includes a greater number of primary sampling units (PSU's) (from 198 in 1994 to 358 for the 1995 design), and a more complicated nonresponse adjustment based on household screening and oversampling of black and Hispanic persons for more reliable estimates of these groups. Additionally, the 1995 population estimates were adjusted to the national population estimates by age, sex, and race/ethnicity, based on projections from the 1990 U.S. Census. Users who combine data from the 1995 NHIS with NHIS data from earlier years must use a modified SUDAAN procedure for estimating sampling errors. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * CONTACT INFORMATION Updates about new data releases, publications, or errors will be sent to members of the NHIS Listserv. To join, visit the CDC website at: http://www.cdc.gov/nchs/about/major/nhis/nhislist.htm For additional information on the NHIS, visit the website at: http://www.cdc.gov/nchs/nhis.htm If you have questions or comments on any aspect of the NHIS, please contact us: E-mail : nhislist@cdc.gov Call : 301-458-4901 FAX : 301-458-4035 Mail : DHHS:PHS:CDC:NCHS:DHIS 3311 Toledo RD Room 2217 Hyattsville MD 20782 Home Page: http://www.cdc.gov/nchs/nhis.htm For additional information on NCHS data products, contact the: Data Dissemination Branch, NCHS 3311 Toledo Road. Hyattsville, MD 20782 Tel: 1-301-458-4636 or 1-866-441-NCHS E-mail: nchsquery@cdc.gov Internet: http://www.cdc.gov/nchs/ STATEMENT OF AUTHENTICITY This material has been cleared for public distribution by CDC/ATSDR and will be authentic if obtained directly from ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/. CDC/ATSDR takes all effort to assure the authenticity of electronically distributed documents. However, in all instances where the electronic and official agency record differ, the authenticity of the official agency record is controlling. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *