Het volume van chirurgische ingrepen en de impact ervan op ... - KCE

KCE Reports 113 Volume Outcome 15
The initial idea was to study the volume outcome relationship for 32 procedures and
medical conditions. To this end, we selected more than 400 000 hospital stays in the
MCD 2004. This large amount of data, however, obliged us to limit the IMA data that
were linked to MCD; although IMA has information on the use of (neo) adjuvant
therapy, only the decease date of patients was retrieved from the IMA database.
Nevertheless, when we were faced with the abundance of 32 procedures and
conditions, it was decided to limit the analyses to 12 surgical procedures. These were
chosen from 3 medical domains: four cardiovascular procedures, three orthopaedic and
five oncologic procedures. The choice of procedures was done in agreement with
Belgian Cancer Registry and internal KCE experts.
12 procedures will be analysed in Belgian data:
Four cardiovascular procedures: carotid endarterectomy and carotid stenting;
coronary artery bypass graft; heart valve replacement or repair; percutaneous coronary
intervention.
Three orthopaedic procedures: total hip replacement; total knee replacement; hip
fracture surgery.
Five oncologic procedures: oesophageal cancer surgery; pancreatic cancer surgery;
colon cancer surgery; breast cancer surgery and lung cancer surgery.
2.3.2.2 Available outcome measures
The following information is unavailable in the data:
1. Mortality within a very specific time frame i.e. 30-day mortality is impossible
since the IMA-AIM mortality date only mentions month and year of decease.
As best possible approximation of the 30-day mortality, we included the
mortality until the last day of the month following the procedure. For
convenience, this is called the approximate 30 day-mortality. The reader
should be aware, though, that this outcome measure covers a post-operative
window of at most 60 days. Two examples might clarify:
• If a patient undergoes a CABG on January 1 st , 2004 and the data tell us
that he deceased by the end of February 2004, we know that he lived at
least 30 days but less than 60 days after the CABG.
• A patient who has a PCI on January 31 st , 2004, who is deceased by the
end of February 2004, will have lived at least 1 day but less than 30 days
after the PCI.
2. Mortality data for this project (provided by IMA-AIM) were only available
until the end of 2006. Consequently, mortality of three years or more after a
procedure (which took place in 2004) is not available. This implies that twoyear
survival is the maximum feasible outcome measure for long-term
mortality.
3. Complication rates within a specific time frame are unavailable because the
MCD admission date only specifies month and year. This makes it, for
example, impossible to study the 30-day infection rate.
4. Information about cancer recurrence is not readily available in the BCR data.
Although information on the length of stay and costs of hospital stays is available in the
MFD, these measures will not be analysed while this study focuses on clinical endpoints
and not on resource utilization.
Table 2.1 gives an overview of the procedures and their outcome variables that were
selected to be analysed with Belgian data.