Latest News – August 2012

Princeton Consumer Research recently carried out the first stage of user trial for a new anti-wrinkle device, developed by the founder of Crystal Clear.  This in-depth trial focussed on the positive effects of the device and involved: silflo replicas being taken, profilometry, cutometry and high resolution close-up photography in order to accurately assess the benefits of the device with the associated formulation.

Recent Policy Changes – August 2012

Comparison between ISO/EN 24444 and the International SPF test method 2006.

Recently here at Princeton Consumer Research, we have noted an increase in the number of enquiries regarding the differences between the Colipa International SPF Test Method, published in 2006, and the more recent ISO/EN 24444 Sun protection test method published in 2011. Below are the key differences and what these mean for studies already completed on your SPF products.


Key Differences Key Similarities
Age RestrictionsThe International Method (’06) did not specify an upper age limit. The ISO24444 method specifies that subjects be no older than 70 years of age. Skin PhototypeOnly Fitzpatrick skin grades of I, II and III can be used.
Skin PhototypeAn ISO24444 study must contain subjects with differing skin phototypes. Solar SimulatorBoth methods recommend the use of a Xenon arc lamp fitted with a WG320 + UG11/1mm filter.
Exposure ProgressionsThe ISO24444 method recommends that progressions of 1.25x be used for the unprotected MED determination whereas the Colipa method recommends either 1.25x or 1.12x. Similarily the ISO24444 method allows progressions of up to 1.15x for SPF products with an expected SPF of 25 or greater whereas the Colipa method allows progressions of up to 1.12x the expected SPF  MEDThe determination and observation of the MED for any treatment is the same between both study designs.
Standard Product (i.e. the P3)The acceptable range of the standard products has been narrowed for the ISO24444 methodology, based on internationally collected data. The P3 for the Colipa method was 13.8-18.7 with a mean SPF of 16.2. The ISO24444 method allows a range of 13.7-17.7 with a mean of 15.7 Number of Subjects to Validate a StudyBoth methodologies require a minimum of 10 subjects to be tested for claim substantiation.


What this means for your tests

Here at Princeton Consumer Research, we have designed (previous to publication) our SPF studies to cater for both methodologies. The more stringent ISO24444 method unknowingly adopts changes to the Colipa 2006 International Method that we ourselves have been incorporating since publication, i.e. the inclusion of a variety of skin phototypes and the progressions for unprotected MED determination. This means that any SPF study completed by Princeton Consumer Research  for your company in the last 6 years is very likely to meet with ISO24444 regulations alongside the authorised Colipa International method.