Pay for Quality

84 Pay for Quality KCE Reports 118
The current results are mainly based on a rapid increasing amount of experience in the
USA and the UK. Although a number of start up countries were also included, they still
are in such a premature phase that the lessons to be learned from their experience are
still limited. However, where appropriate we will refer to their choices of P4Q design
and implementation.
Before discussing the results the following methodological limitations should be taken
into account:
Although the systematic review was performed using multiple databases and several
languages, there exist still other databases and languages which we were unable to
check.
The tool used for the quality appraisal to eliminate low quality primary studies was
based on several existing validated tools, which were combined into a generic tool
applicable to P4Q studies. The use of this combined tool is not validated as such.
Because observational studies are the main source of information on P4Q, it was
decided to report P4Q results comprehensively, without a restriction to randomized
designs. A distinction between strong and weak evidence was made. Selection bias can
therefore not be excluded.
Not all relevant contextual information is available for each of the included studies. For
example, leadership as a factor might impact P4Q results, but is rarely reported upon.
As has become clear in the previous study description section, for the contextual
factors, the P4Q intervention description and the process of implementation and
communication, the completeness of reporting is often lacking in P4Q evaluation
studies.
The limitations in terms of review selection criteria have to be taken into account. A
strict P4Q definition was used (e.g. public reporting is not considered to be a form of
P4Q). The population does not include studies outside a primary care or general
hospital setting (e.g. psychiatric care and nursing homes).
The limitations in terms of studies’ selection criteria have to be taken into account.
With regard to context, studies are more performed in urban areas than in rural areas.
Since a number of studies use a minimal patient panel size per provider or per target for
each provider, it is likely that smaller practices are underrepresented. Furthermore,
because many studies focus upon a stabile and regular type of patients, results may not
be applicable for one time only and quickly physician switching patients. The same is
true for patients who are exception reported in the UK system and are excluded from
most UK study samples, because their performance data are rarely available.
As described in chapter 4 (section 4.2.6), there is a general trend of quality
improvement present in some of the countries where P4Q studies took place, like in
the UK. Only results based on strong evidence take this trend into account to isolate
the P4Q effect from the time trend effect. In addition, P4Q is an intervention that’s
typically combined with other interventions. Because of the mix throughout all P4Q
studies, it is impossible to separate the P4Q impact from the other concurrent quality
improvement initiatives’ impact. The studies discussed here are always based on a
‘bundled’ approach.
P4Q is still a very recent phenomenon. For many medical conditions there is no P4Q
evidence (urology, intensive care, geriatrics, most of surgical care, etc). Secondly, there
are medical conditions for which some first evaluation attempts have been performed,
but for which the evidence is still scarce and no conclusions about P4Q effects can be
drawn (urinary tract infections, skin infections, gastric infections, depression/mental
illness, chronic child care, COPD, epilepsy, hyperthyroidism, chronic cancer care,
osteoarthritis). In more generic terms the same can be said for the introduction of new
drugs and for P4Q effects on the use of most care management processes when
assessed separately.
However, this still leaves a large group of target conditions for which evidence is
available. The effects on the clinical effectiveness domain are reported firstly.