UK DATA ARCHIVE DOCUMENTATION 4588 - Road Accident Data, 2001 Data Archive processing standards --------------------------------- The data were processed to the UK Data Archive's 'A' standard. A rigorous and comprehensive series of checks was carried out to ensure the quality of the data and documentation. The most important procedures were as follows. Firstly, checks were made that the number of cases and variables matched the depositor's records. Secondly, checks were made that all variables had variable labels and all nominal (categorical) variables had value labels. Where possible, either with reference to the documentation and/or in communication with the depositor, absent labels were created. Thirdly, logical checks were performed to ensure that nominal (categorical) variables had values within the range defined (either by value labels or in the depositor's documentation). Lastly, any data or documentation that breached confidentiality rules were altered or suppressed to preserve anonymity. All notable and/or outstanding problems discovered are detailed under the 'Data and documentation problems' heading below. Conversion of data and documentation formats -------------------------------------------- SPSS files created from the fixed-width ascii .txt files originally deposited. The User Guide from the 1999 and 2000 datasets is still valid, so this has been added to the 2001 dataset. All files checked for accuracy and completeness. Useful Notes ------------ 1. Accident record file (acc01): Variable name changes: Many of the variable names contained within each ascii file are in an unsuitable format for SPSS. Therefore, variable names have had to be changed from those listed in the PDF user guide for each file. Variables ACCYR, ACCREF, A3, ACCDAY, ACCMTH, A7, A8H, A8M, A10 and A11 remain the same. Other variables are changed as follows: 1.2 - changed to a1_2 1.5 - changed to a1_5 1.6 - changed to a1_6 1.10 - changed to a1_10 1.12 - changed to a1_12 1.13 - changed to a1_13 1.14 - changed to a1_14 1.15 - changed to a1_15 1.16 - changed to a1_16 1.17 - changed to a1_17 1.18 - changed to a1_18 1.19 - changed to a1_19 1.20A - changed to a1_20a 1.20B - changed to a1_20b 1.21 - changed to a1_21 1.22 - changed to a1_22 1.23 - changed to a1_23 1.24 - changed to a1_24 1.25 - changed to a1_25 1.26 - changed to a1_26 2. Vehicle record file (veh01): Variable name changes: Many of the variable names contained within each ascii file are in an unsuitable format for SPSS. Therefore, variable names have had to be changed from those listed in the PDF user guide for each file. Variables ACCYR, ACCREF, V7, V8, V15, V24 and V25 remain the same. Other variables are changed as follows: 2.4 - changed to v2_4 2.5 - changed to v2_5 2.6 - changed to v2_6 2.7 - changed to v2_7 2.9A - changed to v2_9a 2.9B - changed to v2_9b 2.10 - changed to v2_10 2.11 - changed to v2_11 2.12 - changed to v2_12 2.13 - changed to v2_13 2.14 - changed to v2_14 2.16 - changed to v2_16 2.17 - changed to v2_17 2.21 - changed to v2_21 2.22 - changed to v2_22 2.23 - changed to v2_23 2.24 - changed to v2_24 In December 2004, the breath test data variable (V2_23) was removed from the Vehicle Record file at the request of the depositor. V15: Variable V15 (vehicle prefix/suffix letter) was found to contain numeric codes as well as alphabetical codes for vehicle registration. The User Guide lists the values for these numeric codes as 2 to 5, but the codes contained in the variable run 0 to 4. This was queried with the depositor for the 1999 dataset, who advised UKDA at the time that the correct codes are as follows: 1 Unknown or cherished no. 2 Foreign or diplomatic 3 Military 4 Trade Plates These values have been added to the SPSS file. However, the depositor also advised UKDA at the time that this variable is under review, and that users should be aware that national coverage of this variable is very patchy - its use is strongly discouraged at present. This is still the case for the 2001 data. Variable/value listings in User Guide: Users should note that the variable/value label information given for Vehicle Data on page 6 of the PDF user guide does not list the variables in file order. The Record Layout for Vehicle Records, however, on page 16 of the guide, does list them in file order. 3. Casualty record file (cas01): Variable name changes: Many of the variable names contained within each ascii file are in an unsuitable format for SPSS. Therefore, variable names have had to be changed from those listed in the PDF user guide for each file. Variables ACCYR, ACCREF, C13 and C16 remain the same. Other variables are changed as follows: 3.4 - changed to c3_4 3.5 - changed to c3_5 3.6 - changed to c3_6 3.7 - changed to c3_7 3.8 - changed to c3_8 3.9 - changed to c3_9 3.10 - changed to c3_10 3.11 - changed to c3_11 3.12 - changed to c3_12 3.13 - changed to c3_13 3.15 - changed to c3_15 3.16 - changed to c3_16 C13: Variable C13 (seat belt usage) is noted in the user guide (page 7) as being available for 1979-1993 only, but is present in the 2001 data and also in data for the years 1994-1998 (see other datasets in the series).