list is ordered in ascending order based on the percent difference between actual cost and norm expected cost determined in block 302 such that the physician with actual cost most below the expected cost is ordered first in the list in blocks 304 the number of attending physicians in the selection criteria of a product line for the best practice norm is compared to a predetermined threshold of the number of physicians meeting a selection criteria best practice norm for example the predetermined number of physicians meeting a selection criteria best practice norm can be five attending physicians accordingly if the number of attending physicians in the selection criteria is less than the threshold of the number of physicians meeting a selection criteria best practice norm then no best practice norm is computed for that product line in block 305 an indication that the best practice norm has not been determined can be provided in block 306 the physicians who represent the top u2018 n u2019 of cases of within each apr drg grouping are selected to establish the bpn for illustration purposes the ordered list of physicians in an apr drg grouping is determined which is labeled a through z starting at the first physician in the list physician a the list of physicians is descended and the number of claims for each physician is accumulated until the sum of cases is.