Hello Lynn, sorry for the delay in replying to your message. To answer your question I refer you to the MHRA guidance that was published earlier this year. This guidance is labelled as GMP guidance but I understand it, or very similar guidance, will soon be rolled out across the GxP areas. The guidance defines raw data as: "Original records and documentation, retained in the format in which they were originally generated (i.e. paper or electronic), or as a ‘true copy’. Raw data must be contemporaneously and accurately recorded by permanent means. In the case of basic electronic equipment which does not store electronic data, or provides only a printed data output (e.g. balance or pH meter), the printout constitutes the raw data." The guidance also says that the expectation is "Raw data must:
• Be legible and accessible throughout the data lifecycle.
• Permit the full reconstruction of the activities resulting in the generation of the data".
The guidance goes on to define a true copy as "An exact verified copy of an original record".
Based on all of this, I think the key factors you need to consider are: (1) When will the data be converted to PDF - will this meet the contemporaneous requirement? (2) Will the conversion to PDF be complete (i.e. will you be losing any of the associated meta data by performing this conversion)? (3)How do you want to use the data going forward - I assume you would like to look for trends (e.g. a gradual rise in the temperature over time)? Converting to PDF may make this a less efficient process but that may be outweighed by the other benefits you foresee.
If you can satisfactorily address all of these points I see no reason you cannot convert to PDF provided you validate your conversion process. For information, the FDA have a guidance for industry related to 21 CFR Part 58 (GLP) which was last updated in July 2007. This guidance contains a number of questions with associated answers. One question is "Are photocopies of raw data, which are dated and verified by signature of the copier, considered to be "exact" copies of the raw data?" The answer is "Yes". I believe a validated PDF conversion process could be considered analogous to the verified photocopy.