Scientific validity

Under the MDR, a clinical evaluation is only as strong as the scientific validity of the data behind it. Reviewers look at design, bias control, sample size, follow-up and whether the conclusions really follow from the evidence, so a large volume of weak data does not make up for poor quality. It should not be confused with the IVDR's scientific validity of an analyte.

• ‘scientific validity’, ‘scientifically valid’: this terminology is used in the MDR in reference to clinical data planning, evaluation and conclusions. Clinical evaluations must follow a “defined and methodologically sound procedure”, for which expectations of scientific validity are implicit. Embedded in the term ‘scientific validity’ are concepts including adequacy of study design and controls for bias, appropriateness and relevance of research questions, adequacy of sample sizes and statistical analyses, completeness of data, adequacy of follow up period, and appropriateness of conclusions on the basis of objective evidence. Section 9.3.1 of MEDDEV 2.7/1 rev. 4 provides guidance for the evaluation of methodological quality and scientific validity under the MDD/AIMDD which are equally valid under the MDR which can be considered to apply when referencing ‘scientific validity’ in this guidance.

MDCG 2020-6, Section 1.2, Additional terms not defined in MDR Article 2