How to reinforce the proficiency of SPF testing
439
Presented by: Florence POURADIER
OBJECTIVE:
As photoprotection is about public health, sunscreen labelling must be sincere and reliable. Performance on UVB or UVA protection (expressed through SPF or UVA-PF) and Water-resistance is determined through standardized methods (e.g. ISO 24444 for SPF). Considering the importance to control the quality of the performed determination, all these standards consider the use of sunscreen formulation reference to validate the test, on each of the volunteers included in the trial.
To reinforce this approach, we choose to also include in our main photoprotection studies well-known formulae, representative of marketed products. Through this approach, we were able to collect a large amount of data, from different labs, worldwide.
The objective of this study was to investigate how this data could be exploited, beyond the one-point approach test by test, to reinforce our global quality process and leverage knowledge on testing of the same formula across different world populations.
METHODS:
We consider in this study 3 formulae from our database:
RESULTS:
Being inspired by BIPEA’s approach and referring to the ISO 13528 standard, we define a “z-score” which is continuously updated by considering the global data from a formula to calculate an accepted range. The z-score reveals to be a relevant and useful criterion to assist the study sponsor in validating the reliability of the obtained results.
Analysis of the data obtained on the 3 same formulae worldwide proves that consistent results can be obtained from different populations when measured with the same standardized method.
CONCLUSION:
This approach allows us to control both the instantaneous performance and the continuous performance of the laboratory (quality assurance by different properties: bias, stability, and repeatability), ensuring the robustness of the SPF determination. The analysis of the resulting database highlights the consistency of the value obtained from different population across the world on which this standardized determination is performed.
As photoprotection is about public health, sunscreen labelling must be sincere and reliable. Performance on UVB or UVA protection (expressed through SPF or UVA-PF) and Water-resistance is determined through standardized methods (e.g. ISO 24444 for SPF). Considering the importance to control the quality of the performed determination, all these standards consider the use of sunscreen formulation reference to validate the test, on each of the volunteers included in the trial.
To reinforce this approach, we choose to also include in our main photoprotection studies well-known formulae, representative of marketed products. Through this approach, we were able to collect a large amount of data, from different labs, worldwide.
The objective of this study was to investigate how this data could be exploited, beyond the one-point approach test by test, to reinforce our global quality process and leverage knowledge on testing of the same formula across different world populations.
METHODS:
We consider in this study 3 formulae from our database:
- Formula 1 (medium protection): 378 individual data from 60 studies, from 10 labs located in Europe (3 countries), Canada, US, Singapore.
- Formula 2 (high protection): 2076 individual data from 222 studies, from 15 labs located in Europe (6 countries), Canada, Brazil, China, Japan, Singapore.
- Formula 3 (very high protection): 2473 individual data from 306 studies, from 15 labs located in Europe (6 countries), Canada, Brazil, China, Japan, Singapore.
RESULTS:
Being inspired by BIPEA’s approach and referring to the ISO 13528 standard, we define a “z-score” which is continuously updated by considering the global data from a formula to calculate an accepted range. The z-score reveals to be a relevant and useful criterion to assist the study sponsor in validating the reliability of the obtained results.
Analysis of the data obtained on the 3 same formulae worldwide proves that consistent results can be obtained from different populations when measured with the same standardized method.
CONCLUSION:
This approach allows us to control both the instantaneous performance and the continuous performance of the laboratory (quality assurance by different properties: bias, stability, and repeatability), ensuring the robustness of the SPF determination. The analysis of the resulting database highlights the consistency of the value obtained from different population across the world on which this standardized determination is performed.