Everyone uses Excel Spreadsheets. Also in pharmaceutical companies, Excel Spreadsheets are used in different departments. The easy to use calculations allow making calculations in a very convenient way. Yet, this can also represent a huge risk. In a pharmaceutical environment, computerized systems need to be validated. Spreadsheets also need to comply with a number of requirements. However, controls are quite often inadequate and this may result in a compliance risk.
When it comes to spreadsheets, what should be validated? A Q&A issued by EMA provides the following answer: "Validation according to paragraph 4 of annex 11 is required at least for spreadsheets that contain custom code (e.g. Visual Basic for applications). Formulas or other types of algorithm should be verified for correctness." Therefore, appropriate controls for templates of spreadsheets must be in place. Erroneous calculations due to data remaining from previous calculations must be avoided. The templates should also be suitably checked for accuracy and reliability (annex 11 p7.1) and should be stored in a manner which ensures appropriate version control (chapter 4 p4.1).
When it comes to accuracy checks (as required in Annex 11 p 6), data integrity is an important issue. The Q&A document explains that both the files and the calculations should be secured in such a way that formulations are not accidentally overwritten. Accidental input of an inappropriate data type should be prevented or result in an error message.
Source: industry and authority question and answers on GMP by EMA - summarized in the ECA Question and Answer Guide