Process

Expected time for completion

Deadline

Data specification and request

• Addition of new variables / codes to data specifications
• Distribution of data specifications and request for data to centres.
  The request is for data for all patients ever seen for care at a centre

6 weeks

19/12/2008

Checking general integrity of data from sites (not of individual records)

• Recode/manipulate centre-specific data so that it conforms with data specifications
• Tabulate all variables to identify obvious errors
• Check of new data against previous data submission for each centre
• Resolve any problems arising from above with local data manager
• Clean ART data from each centre via SAS program: includes removal of overlapping datees and short breaks (<14d)

3.5 months

20/03/2009

Import of data into database

• Prepare data files as tab delimited text files, with dates in dd/mm/yyyy format, and include leading zero's
• Import data into database

3 weeks

09/04/2009

Data cleaning of individual records

• Print out within-centre data queries and consistency checks using pre-existing queries and reports at MRC
• Liaise with data managers/assistants/research nurse or visit centre to resolve errors
• Individual edits applied to the database (maintains audit trail)

2 months

05/06/2009

Notify centres:

• send summary of centre-specific data and the results of the cleaning process i.e how many inconsistencies identified and resolved
• feedback results of data checks for centres to update their local database

1 week

12/06/2009

De-duplication

• Run de-duplication program
• Manually resolve any ambiguous matches
• Merge demographic, AIDS, ART and other data files

6 weeks

31/07/2009

Data export

• Export data as text files to study statistician
• Final SAS manipulation of files (by study statistician) to resolve outstanding data quirks
• Export selelcted data to other statisticians as required
• Notify sites that they may have an export of their own (cleaned) data if required

1 month

31/08/2009