USING SAS WITH NAMCS DATA
   
  There are two ways to read the 2014 NAMCS public use data file using SAS:

  Option 1 - Use the zipped file namcs2014_sas.zip in the SAS folder on 
  the FTP server to open a complete SAS dataset of the 2014 NAMCS public use file.

  The steps for this option are as follows:

  1) Create a new folder on your local workstation, for example, 'c:\myfiles\namcs'

  2) Download to the new folder the file namcs2014_sas.zip and the file nam14for.txt 
     from the FTP server: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/dataset_documentation/namcs/sas

  3) namcs2014_sas.zip is a compressed file which you must unzip prior to use. 
     In order to do this, double click on the file name in your directory screen; 
     an option to unzip the file should appear. Once you have selected the unzip option, 
     a new unzipped file called namcs2014_sas.sas7bdat should appear. This is the SAS 
     dataset. You can then move the file to your preferred location.

     nam14for.txt is the file containing the formats which you will need to include in your
     program in order for the SAS file to run.  

  4) To use the SAS dataset, the following code provides an example for a file saved to 'c:\myfiles\namcs':

     %inc "c:\myfiles\namcs\nam14for.txt";  /*read in the SAS formats*/
     libname out1 'c:\myfiles\namcs';  /*point to file location on your workstation*/
     data test14; set out1.namcs2014_sas;  /*create a temporary working file copied from the unzipped file*/
     proc surveyfreq data=test14;
     tables sex*ager /clwt cl;
     cluster cpsum;
     strata cstratm;
     weight patwt;
     run;
 
  Option 2 - Use the SAS input, label and format files provided to create your own SAS data set. 

  The steps for this option are as follows:

  1) Create a new folder on your local workstation, for example, c:\myfiles\namcs

  2) Download to the new folder the 2014 NAMCS ASCII dataset (namcs2014.zip) from the FTP server: 
     ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/datasets/namcs

  3) namcs2014.zip is a compressed file which must be unzipped prior to use.
     In order to do this, double click on the file name in your directory screen; 
     an option to unzip the file should appear. Once you select the unzip option, a new file 
     called namcs2014 should appear.  This is the unzipped NAMCS ASCII dataset and has no file 
     extension. You can then move the file to your preferred location. 

  4) Download to the new folder the nam14inp.txt, nam14lab.txt and nam14for.txt files from the FTP server:
     ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/dataset_documentation/namcs/sas

  5) Sample SAS code is shown below; other examples can be found here: 
     https://www.cdc.gov/nchs/ahcd/ahcd_presentations.htm

     filename nam14pub "c:\myfiles\namcs\namcs2014";        /*unzipped ASCII data set*/
     filename nam14for "c:\myfiles\namcs\nam14for.txt";     /*SAS format statement*/
     filename nam14inp "c:\myfiles\namcs\nam14inp.txt";     /*SAS input statement*/
     filename nam14lab "c:\myfiles\namcs\nam14lab.txt";     /*SAS label statement*/

     %inc nam14for;  /*reads in the formats*/

     data test14; 
     infile nam14pub missover lrecl=9999;
     %inc nam14inp;  /*reads in the input statement*/
     %inc nam14lab;  /*reads in the labels*/
     run;

     proc surveyfreq data=test14;
     tables sex*ager /clwt cl;
     cluster cpsum;
     strata cstratm;
     weight patwt;
     run;


   CAUTION - Because the NAMCS is a sample survey, the application of 
   weights to the sample data is REQUIRED to produce national estimates
   of office visits, as well as to accurately assess the sampling error of
   statistics based on the survey data.  Please refer to the appropriate
   sections of the documentation file for information on how to apply the 
   weights and to obtain relative standard errors of national estimates.
                                                                                                
   For questions, suggestions, or comments concerning NAMCS data, please
   contact the Ambulatory and Hospital Care Statistics Branch at 
   (301) 458-4600 or by email at ambcare@cdc.gov. 

   For additional information on NCHS data products, please call CDC-INFO at 
   800-CDC-INFO (800-232-4636), TTY (888-232-6348), Monday-Friday 8am-8pm EST, 
   or use the CDC-INFO online request form at https://www.cdc.gov/info.