Percent reduction in infestation rate on a consignment basis for bark- and wood-infesting insects in WPM associated with US imports after implementation of ISPM15, using two different dates to separate pre- and post-ISPM15 and different country groupings.

aAll countries were included in the analyses except various combinations of Canada (CA), China (CN), and Mexico (MX). See text for details.
bTotal = number of consignments analyzed after dropping the data from the selected countries listed. Pre- and Post-ISPM15 values, in order of appearance, are the number of pre-ISPM15 consignments with and without pests, and the number of post-ISPM15 consignments with and without pests. These were the values used in the contingency tables.
cAnalyses were conducted on AQIM records with WPM from 1 October 2003 through 30 September 2009. The United States implemented the first phase of ISPM15 on 16 September 2005 (Phase 1) and the final phase on 5 July 2006 (Phase 3).
dInfestation rates were based on the table values presented here under ‘No. consignments.’ For example: (12/6327) *100 = 0.1897%.
ePercent reduction is based on the difference between the pre- and post-ISPM15 infestation rates as given in this table. The formula used was [(Pre – Post) *100/Pre]. The P values were based on 2 x 2 contingency tables using the values presented in this table and analyzed with the Fisher’s exact test (right-sided).