To assess the impact of specialization on processes and outcomes of care for cancer
patients.
Papers published in English between 1980 and 1995 and identified through MEDLINE and
Embase (MeSH terms: NEOPLASM (exploded), and PHYSICIAN PRACTICE PATTERNS (or DECISION
MAKING, ATTITUDE OF HEALTH PERSONNEL, QUALITY OF HEALTH CARE, DELIVERY OF HEALTH CARE,
HEALTH EDUCATION or OUTCOME ASSESSMENT HEALTH CARE), or through the reference lists
of review articles.
Studies providing information on the association between quality of care indicators
for cancer patients and clinician/centre degree of specialization. A total of 47 papers
concerning 46 empirical studies were considered.
For studies using process of care indicators, the proportion of specific procedures
performed by specialists and non-specialists was abstracted. For studies using outcome
indicators (e.g., mortality), the effect of specialization was quantified in terms
of odds ratio (OR) expressing relative reduction in risk of death. The quality of
individual studies using process or outcome indicators was assessed according to study
design, avoidance of selection bias in patient identification and data analysis, degree
of adjustment of the comparison between clinicians/centres with different levels of
specialization.
Specialized centres/clinicians fared better both when process and outcome indicators
were used. While the former varied widely in different studies and their clinical
relevance was often questionable, mortality was consistently lower when care was provided
by specialized centres/clinicians, with the effect size being greater in smaller studies.
For breast cancer, where all the studies were of sufficiently good quality, a pooled
estimate of the effect of specialization was performed which showed that specialized
cancer care was associated with an 18% (95% CI: 12%-23%) reduction in mortality.
Despite the fact that care provided by specialized centres/clinicians appeared to
be better both when assessed in relation to process indicators and to mortality, this
evidence should be considered far from conclusive because of major methodological
flaws in these studies. Relative to current efforts to promote evidence-based policy-making,
this review underscores the limited capability of scientific information to provide
reliable guidelines for structuring better health care systems.