Despite substantial progress made in increasing colorectal cancer (CRC) screening adherence, how to appropriately measure CRC screening adherence and how to apply the measurement for evaluating interventions designed for improving CRC screening adherence remain challenging.
This study has two objectives. First, this project is to construct a longitudinal, repeated, individual-level measurement of VA-wide performance in CRC screening adherence by average-risk veterans, Second, this project is to examine the effects of a VA health information technology application (i.e., VISN 7 Colorectal Cancer Oncology Watch Intervention) on CRC screening adherence.
This study will use VA Medical SAS and Fee Basis claims-based data to longitudinally measure individual-level CRC screening adherence among non-elderly average-risk veterans over a 10-year period from 2001-2010.
The first study showed a new application of VA administrative data for measuring VA system-wide performance of colorectal cancer (CRC) screening adherence among veterans at average-risk for CRC. The new measurement has two features: it is specifically designed for average-risk populations and is applied repeatedly at the veteran level each year over the study period. Using 1997-2007 VA administrative data, we developed an algorithm that first constructed 7 independent cohorts of average-risk veterans eligible for CRC screening, one for each year from 2001 to 2007, and then appended the seven cohorts together to form 2001-2007 veteran-level panel data. Veterans in a cohort for a given year were considered adherent if they received fecal occult blood test (FOBT) during that given year, or received flexible sigmoidoscopy (FS), double-contrast barium enema (DCBE), or colonoscopy during that given year or the 4 previous years. The main analysis shows that VA CRC screening rates increased from 30.11% in2001 to 35.51% in 2004, but declined to 31.54% in 2007. Among the screened, the proportion adherent to colonoscopy increased over the 7-year period while the proportion adherent to FOBT, FS, or DCBE decreased during the same period.
A second study evaluated the CRC Oncology Watch intervention, a clinical reminder implemented in VISN 7 (including 8 hospitals) to improve CRC screening rates in 2008. This study used VA administrative data to construct 4 cross-sectional groups of average-risk, age 50-64 veterans, one for each of 2006-2007 and 2009-2010. We applied hospital fixed-effects for estimation, using a difference-in-differences model in which the 8 hospitals served as the intervention sites and the other 121 hospitals as controls, with 2006-2007 as the pre-intervention period and 2009-2010 as the post-intervention period. The sample included 4,352,082 veteran-years in the 4 years. The adherence rates were 37.6%, 31.6%, 34.4%, and 33.2% in the intervention sites in 2006-2007 and 2009-2010, respectively, and the corresponding rates in the controls were 31.0%, 30.3%, 32.3%, and 30.9%. Regression analysis showed that among those eligible for screening, the intervention was associated with a 2.2-percentage-point decrease in likelihood of adherence (P<0.0001). Additional analyses showed that the intervention was associated with a 5.6-percentage-point decrease in likelihood of screening colonoscopy among the adherent, but with increased total colonoscopies (all indicators) of 3.6 per 100 veterans age 50-64. This study concluded that the intervention had little impact on CRC screening rates for the studied population. This absence of favorable impact may have been caused by an unintentional shift of limited VA colonoscopy capacity from average-risk screening to higher-risk screening and to CRC surveillance, or physicians' fatigue due to the large number of clinical reminders implemented in the VA.
There were two major publications, supported by this VA Merit Award. The first article described an innovative algorithm used to measure CRC screening adherence at the individual level among non-elderly veteran level over a 7-year period from 2001 to 2007.
A second article (and a reply to the comments on the second) evaluated the effects of the CRC Oncology Watch intervention, implemented in eight Veterans Affairs hospitals within VISN 7 during fiscal year 2008, on CRC screening adherence. Our results suggested that although the intervention was surprisingly associated with slightly lower overall screening adherence for the studied population, it may have potentially improved efficiency of colonoscopy utilization by directing limited colonoscopy capacity to higher risk screening, diagnostics, and surveillance purposes.
The impact of this project is two-fold. First, our claims-based, individual-level measurement of CRC screening adherence represents a more efficient and more accurate way for measuring quality of CRC cancer screening, applicable not only for veterans but also for non-veterans. Second, the longitudinal structure of this measurement may open opportunities for better conducting comparative effectiveness research of CRC screening technologies that are often subject to measurement errors and selection biases. Furthermore, we have demonstrated the feasibility of using this measurement for evaluating an intervention designed to assess performance of CRC screening adherence.
- Bian J, Bennett C, Fisher D, Riberio M, Lipscomb J. Reply to S.P.Sura et al. Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 2013 Jul 1; 31(19):2512.
- Bian J, Bennett CL, Fisher DA, Ribeiro M, Lipscomb J. Unintended consequences of health information technology: evidence from veterans affairs colorectal cancer oncology watch intervention. Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 2012 Nov 10; 30(32):3947-52.
- Bian J, Fisher DA, Gillespie TW, Halpern MT, Lipscomb J. Using VA administrative data for measuring colorectal cancer screening adherence among average-risk non-elderly veterans. Health Services and Outcomes Research Methodology. 2010 Jan 1; 10:165-177.