To estimate the value of process validation, a systematic evaluation of the collected opinions and experiences of it was performed using technology assessment (TA). TA is an evaluation process that aims to protect people/society from the consequences of rapid technological developments and attempts to identify all the possible impacts of a technology, not just the intended ones.1 Today, technology in this context refers not only to the logical products of science, but also to the attitudes, processes, apparatus and consequences associated with it, and in that wider meaning, the principles of TA are well suited to the evaluation of process validation as a tool for pharmaceutical manufacturing.
Delphi method. The procedure used in the Delphi method aims at structuring and distilling the mass of information from a selected group of experts by means of a series of questionnaires based on a structured process with controlled feedback.4 Moreover, this method was chosen for the following benefits:
- it enables participants from various countries and different fields (industry, authorities, schools) to take part
- it allows anonymous participation; a benefit that was of special value because the survey intended to facilitate discussion between the industry and its authorities, and to obtain comments from different organizational levels
- participants can take part asynchronously; that is, one may choose when to participate
- participants can choose to contribute to areas in which they are best qualified.
For development in the Delphi survey, see sidebar "Changes in the Delphi survey."
The replies to one round of questions are summarized and used to construct the next questionnaire. This reiterative process is continued until consensus or clear disagreement is reached among the participants.
Locating experts One disadvantage of the Delphi method is the definition and selection of experts; that is, whom to regard as an expert and how to create a representative group.
For this survey, experts were defined as those people working on process validation in:
- the pharmaceutical industry
- pharmaceutical authorities
- pharmaceutical schools
- consultant companies.
Representatives of the pharmaceutical industry were chosen from quality assurance, production and product development positions; representatives of the authorities had to either evaluate pharmaceutical and chemical aspects of the marketing authorization applications or work in inspection; and the representatives of pharmaceutical education had to teach process validation. Further details were unspecified; educational background was disregarded and the objective was to obtain the widest possible representation of different organizational levels. The level of experience of pharmaceutical process validation would have been of interest, but because of the limited number of experts in the field, this issue was not used as an exclusion criterion.