Proficiency testing of laboratories for paralytic shellfish poisoning toxins in shellfish by QUASIMEME: A review

Data from these exercises is presented and laboratory performance is assessed to determine any changes in overall performance over the six rounds, together with any potential method-related performance issues. The data showed the improvement of laboratories over the six exercises with between laboratory CV% values decreasing from an average of 39% in the first year to 22% in 2014 and the average percentage of participants receiving satisfactory z-scores increasing from 50% in 2009 to over 66% in 2014.