Coding of procedures can both clarify and reduce information.
Coding of procedures has been validated, with a data accuracy of 93% reported (NHS National Services Scotland 2007).
In addition, many hospitals lack official training programs for coding of procedures (Lofthus et al. 2005).
However, coding of procedures is time-consuming, and is an additional administrative task over and above practical care [ 23, 24].
Nonetheless, owing to direct economic incentives, coding of procedures in the Danish National Health Service Registry is considered highly valid.
As in VA databases, coding of procedures is with ICD-9 procedure codes, although coding is not as extensive, with a maximum of 4 procedures per hospitalization.
A panel of experts was consulted for issues that needed clarification both regarding the identified procedures and the coding of procedures.
While coding of procedures and primary diagnoses in the hospital episode statistics is fairly complete, coding of secondary diagnoses (used for several AHRQ indicators) is less complete, hence the adverse outcome rates are likely to be underestimated.
With all approaches, there is under reporting as a result of poor compliance with completing audit data, incorrect coding of procedures (Cockbain et al, 2012) and treatment of patients for complications in primary care or in institutions other than the hospital where the initial surgery was performed.
"There are so many different practices going on, it is difficult to get agreements on a standard code of procedure," says Quest.
