NHS England announced a change in July 2024 for PCN DES IIF indicator CAN02 to become CAN04. This follows months of a known data quality issue for EMIS where Practices "... may not have accurate indicator values".

CAN02 is also known as NCD123.
Problem
EMIS had been reporting a single number for each of the denominator and numerator - see below where the table counts clinical codes. The same behaviour had been happening in CAN01 (NCD112) in previous contract years.
The problem with this is that it counts every instance of a code, so a double coded referral would increase the denominator while a double coded fit test might increase the numerator. This led (usually) to some very low achievement scores due to the sheer number of referral codes for the same episode (eg: the doctor codes it, then the secretary codes it on the eRS referral, and the code is attached to the proforma).
PCIT had always got around this problem using the following numerator report which counted one episode per patient per month. The reality of cancer referrals is that most patients would only have 1 during the year, or potentially a separate second referral months later. This approach proved to be more accurate, with the caveat that a QFIT and referral coded at the end of one month and another referral code for the same episode was coded early in the next month would count twice (eg: referral coded by doctor on afternoon of Friday 30th, and secretary completes the referral with another code on Monday 2nd).
Investigation
The problem hasn't stopped there, although this next element was only reported to NHS England in late July 2024.
The effective parent search in Enquiry Manager for the above CAN02 numerator report is called FAECIMM_COD (2).
The rule here is written very similarly to how PCIT produced the rule and it works. This counts all of the patients who had a referral and a QFIT in the correct timeframe.
The problem is that the report uses a criteria of NCD123 GICANREF DATE . This exposed a problem where not all of the patients in the FAECIMM_COD (2) search were being listed in the report.
We found where a referral and QFIT are exclusively coded on the same date (that is, there is no QFIT code between 21 and 1 day before the referral), GICANREF ignores them, reducing the numerator.
Solution
NHS England's solution has been to introduce CAN04 to replace CAN02. The description for this is:

The proportion of patients who have had a lower gastrointestinal urgent suspected cancer referral in the reporting year where at least one urgent suspected cancer referral was accompanied by a faecal immunochemical test result, with the result recorded in the 21 days leading up to the referral.
This basically means a patient is counted in the numerator if there is a single counting episode, much like QOF indicators. In practical terms, this is likely to mean that EMIS will use the search FAECIMM_COD (2) as the numerator underneath a parent of patients aged greater than equal to 65 years. The denominator will be the search Percentage of lower gastrointestinal two week wait (fast track) cancer referrals. Reports used up until now will be redundant.

In addition to CAN04, CAN03 replaces CAN01 which has been a Management Indicator since April 2023 - this tracks where the FIT could be coded between 21 days before and 14 days after the referral. Again, the indicator will count patients rather than the number of codes.