A printed analytical worksheet with space for the following information should be used by the analyst to confirm that the sample has been examined in accordance with the requirements and, when necessary, to provide documentary evidence to support regulatory action:
- the registration number of the sample;
- the date of the test request;
- a description of the sample received;
- the quality specifications to which the sample was tested (including any additional or special methods employed);
- the results obtained, including any calculations necessary;
- the interpretation of the results and final conclusions.
Additional space should be provided to indicate whether and when portions of the sample were forwarded to other units for special tests (e.g. sterility, infrared spectrum), and the date when the results were received. To ease the flow of information between collaborating units a further set of printed forms can be useful. These can be sent out in duplicate from the lead unit with the sample to which they refer. In due course one copy is returned to the lead unit for attachment to the analytical worksheet, while the other is retained in the unit that undertook the work.
A separate analytical worksheet should be completed for each numbered sample. Each completed worksheet should be signed by the analyst responsible, initialled by the supervisor and placed on file for safe-keeping together with any attachments, including calculations and tracings of instrumental analyses. If this information is filed centrally in a registry, a copy of the worksheet should be retained in the lead unit for ease of reference.
It is still the custom in many laboratories for each analyst to keep a complete record of his work in a bound laboratory notebook with numbered pages. Although this has value it is an inconvenient form of documentation in a modern laboratory where results obtained on recording instruments or printed calculations have to be entered into the worksheet. If such a notebook is kept, it should be regarded as a supporting record only.
On the day the sample is received in the unit, the registration number, the date, the name of the product, and a description of the material received should be entered on the analytical worksheet. The information contained in the test request should be checked against the data on the label and the findings recorded, dated, and initialled. Any discrepancies in the documentation, or between the data provided and the appearance of the sample, should also be recorded. Any queries should immediately be referred back to the provider of the sample.
The analyst must then determine what specification is to be used to assess the sample. In many cases, the test request will specify a particular pharmacopoeial monograph or manufacturer’s specification and the analyst must find out whether the current version is available. If no precise instructions are given, the specification in the officially recognized national pharmacopoeia should be used or, failing that, the manufacturer’s officially approved or other nationally recognized specification. The reference number of the specification should be entered on the worksheet and a photocopy of the document attached.
If no formally approved specification exists, preference should be given to a current monograph in a foreign pharmacopoeia. If no suitable pharmacopoeial monograph can be found, the requirements should be drafted in the laboratory itself on the basis of published information and any other relevant documentation (1, 2). Otherwise, if the general policy of the laboratory permits, the specification contained in the product licence may be requested from the manufacturer. Whatever happens, detailed notes on the specification selected and the methods of assessment used must be entered in the worksheet.