This study examined the organizational and environmental characteristics associated with accrual in the NCI’s CCOP program. One of the most striking findings in the analysis may be that, compared with analyses of the prior decade [7
], very few traditionally-measured CCOP organizational or environmental characteristics remain associated with CCOP accrual performance. A hallmark of the CCOP has been its long history of performance data collection and a philosophy of systematic self-examination to inform continuous improvement [1
]. As the CCOP continues to embrace this philosophy and engage in strategic planning efforts, also incorporating guidance from the recent IOM and OEWG [3
], one of its most important priorities may be to examine new measures associated with organizational performance and implement them to augment the set of measures it currently collects.
Interpreting the results of this analysis in the context of prior research, we see current CCOPs experiencing higher per-CCOP accrual in current years, suggesting greater efficiencies in operation than before. The CCOPs had a comparable number of CP/C trials open, though substantially fewer treatment trials open compared to the 1990s. Given this trend, it may be the case that funding previously allocated to administrative staff for opening and processing trials may have been reallocated to fund more staff that enrolled or helped manage patients on trials, and thus be a key driver of the apparent accrual efficiencies. CCOPs in the 2000s tended to be larger and have a slightly greater number of accruing physicians than those in the 1990s, further suggesting that achieving a “critical mass” may be associated with CCOP success. This may be through greater programmatic stability (i.e., better able to absorb individual physicians coming and going) or broader access to additional funding from affiliated hospitals and clinical programs. Alternatively, it may offer enhanced access to a greater number of patients or a more diverse patient population. This may also be reflected in CCOPs recently being affiliated with a greater number of Research Bases than before, with associated access to a more diverse set of clinical trials from which to choose to meet the needs of the more diverse population.
The non-significance of HMO penetration and hospital competition suggests that CCOPs able to adapt to the disruptive changes in healthcare financing seen in the 1980s and 1990s were more likely to survive and thrive in the 2000s. It may also indicate that the once-volatile market characteristics are in fact less disruptive than they once were.
For CP/C accrual, surprisingly few factors are strongly predictive of performance compared to those associated with either CP/C in the 1990s or with treatment accrual in the 2000s. Another notable contrast is the physician accrual profile, in which treatment trial performance appears to have favored few physicians who were responsible for most accrual, compared to a broader set of physicians with more equal accrual among CP/C trials. Comparing CP/C and treatment models further, statistical specification tests suggested that a different model (Random Effects estimation) had a better fit for CP/C compared to treatment (Fixed Effects estimation). Together, these points jointly suggest that factors associated with CP/C accrual performance are fundamentally different from those associated with treatment accrual. In practical terms, this observation reflects the reality of CCOP operations and is quite logical, as treatment accrual tends to take place in oncology practices while CP/C accrual commonly takes place in a much broader set of clinical as well as non-clinical settings. Therefore, it makes sense that organizational and environmental factors associated with oncology treatment may differently affect accrual to treatment trials compared to accrual to CP/C trials, for example, in primary care practices, follow-up clinics, or the broader non-clinical community.
Study findings suggest that, more so than clinical competition, there may be academic competition. Specifically, there tends to be less accrual among CCOPs in communities with a stronger academic presence vis-à-vis the proportion of hospitals affiliated with a medical school. It may be that patients who would contemplate enrollment in a clinical trial would be likely to accept referral or self-refer to an academic center, rather than refer to a CCOP practice. On one hand, this speaks to the CCOP’s strategic priority focus outside of the academic medical centers, and the establishment of local CCOPs in communities that do not have a medical school. Conversely, it may be that CCOPs in communities with a strong academic presence are functionally different from other CCOPs either in terms of their structure, the trials they offer, the strength or consistency of referral relationships, or the different practice focus and priorities of CCOP practitioners in these communities. Again, we look at the trend toward greater treatment trial accrual among CCOPs with low accrual equity physicians (i.e., a small proportion of physicians have a preponderance of accrual). There are several possible causes of this phenomenon. CCOP physicians in communities where there is an academic presence may feel greater pressure to more broadly serve the practice organization’s many missions, rather than “specialize” in clinical research. This may contrast to communities without academic centers, where the CCOP may be the only source of clinical trial participation, and thus functionally serve as “the academic center” for that community, in turn promoting cultural norms that encourage specialization in different areas among professionals — clinical care, research, and others. Additionally, this finding may indicate that a dynamic, motivated physician may provide a bolus in trial enrollment. It may also suggest that small practices with a strong focus on trial enrollment may outperform their larger peer practices. Further research should examine these issues, as understanding them may inform CCOP organization and physician practice focus, and strengthen those CCOPs operating in both academic and non-academic communities.
Among study limitations, our study involves a sample of only 45 CCOPs followed for eight years. Though this represents nearly all CCOPs, it is a small sample to examine with fixed effects and random effects estimation, and close attention must be paid to balance sufficient model specification with a need for erring on the side of parsimony in terms of degrees of freedom. A tradeoff of being parsimonious is that this minimally-specified model may suffer from excluding relevant variables. This study examined the variables collected by CCOPs that were most relevant and incorporated additional measures. However, there may be other environmental and organizational factors or patient population, physician, hospital and clinical trial specific characteristics that may have had an effect on clinical trial accrual for which our model did not control. If these factors truly belonged in the model, omitting them will result in biased estimates. As the CCOP goes forward to identify additional relevant variables, understanding the relative strength of relevance for each will be important.
Among other issues, many of our environmental variables are linked to the CCOPs by the MSA where the CCOP headquarters is located, which is suboptimal because some CCOPs are active in more than one MSA. In these instances, variables such as hospital competition or HMO penetration might not comprehensively reflect the environment in which the CCOP actually operates. However, most CCOPs operate in a limited region, and for this study sample, there was limited variation with these regions, and thus limited risk of bias due to this measurement method. In this study, hospital competition was based on the number of hospital admissions; given the outpatient nature of the majority of cancer care, it may be more relevant to measure hospital competition differently in the future. Finally, physician competition was measured using the number of practicing physicians in the MSA. Given that this study focuses on clinical trials for cancer patients, it may have been more accurate to reflect physician competition in terms of practicing oncologists in the MSA or CCOP service area. This data was not available for this study.