| | Timely Follow-Up of Positive Fecal Occult Blood Tests: Strategies Associated with Improvement published online 15 June 2009. BackgroundIn light of previous research indicating that many patients fail to receive timely diagnostic follow-up of positive colorectal cancer (CRC) screening tests, the Veterans Health Administration (VA) initiated a national CRC diagnosis quality-improvement (QI) effort. PurposeThis article documents the percent of patients receiving follow-up within 60 days of a positive CRC screening fecal occult blood test (FOBT) and identifies improvement strategies that predict timely follow-up. MethodsIn 2007, VA facilities completed a survey in which they indicated the degree to which they had implemented a series of improvement strategies and described barriers to improvement. Three types of strategies were assessed: developing QI infrastructure, improving care delivery processes, and building gastroenterology capacity. Survey data were merged with a measure of 60-day positive-FOBT follow-up. Facility-level predictors of timely follow-up were identified and relationships among categories of improvement strategies were assessed. Data were analyzed in 2008. ResultsThe median facility-reported 60-day follow-up rate for positive screening FOBTs was 24.5%. Several strategies were associated with timeliness of follow-up. The relationship between the implementation of QI infrastructure strategies and timely follow-up was mediated by the implementation of process-change strategies. Although constraints on gastroenterology capacity were often sited as a key barrier, implementation of strategies to address this issue was unassociated with timely follow-up. ConclusionsDeveloping QI infrastructure appears to be an effective strategy for improving FOBT follow-up when this work is followed by process improvements. Increasing gastroenterology capacity may be more difficult than improving processes of care. Background  Colorectal cancer (CRC) is the third leading cause of cancer death among American men and women.1 It is estimated that one in 18 Americans will be diagnosed with CRC over their lifespan. Screening programs aimed at early diagnosis of cancer and removal of precancerous polyps have been demonstrated to reduce both CRC incidence and mortality.2 Multiple tests for CRC screening are available, however most VA patients are screened using fecal occult blood tests (FOBTs).3 To benefit from FOBT screening, positive results should be followed with a diagnostic colonoscopy.4 Research indicates that while many U.S. healthcare plans have systems in place to promote CRC screening, few have a process to monitor follow-up of positive results.5, 6 It is therefore not surprising that several studies have found that the majority of patients with a positive screening test fail to receive a compete diagnostic exam in a timely manner.7, 8, 9, 10 Although the relationship between positive-FOBT follow-up intervals and clinical outcomes is unknown, excessive delay in cancer diagnoses has been linked to increased patient stress and decreased satisfaction with care.11, 12, 13 In 2006, the Veterans Health Administration (VA) launched a national effort to increase the proportion of patients receiving a colonoscopy within 60 days of a positive FOBT lab result. This 60-day interval was determined based on consensus among VA clinical and operations leadership. The project was based on the premise that the first step to sustainable improvement is the development of a quality-improvement (QI) infrastructure. All VA medical centers were encouraged to establish multidisciplinary quality improvement teams, work collaboratively with other facilities, and develop data-collection and patient tracking systems. Sites were to use this infrastructure to identify barriers, choose strategies to improve processes of care and/or gastroenterology capacity, and monitor the effects of implementing these strategies. It was therefore anticipated that the development of QI infrastructure would not have a direct (unmediated) effect on timely follow-up, but would instead lead to the implementation of changes to processes of care and/or efforts to increase colonoscopy capacity that would in turn improve rates of timely follow-up. This article reports the proportion of VA patients with a positive FOBT CRC screening test between March and June 2007 who received a colonoscopy within 60 days and examines the association between the implementation of various improvement strategies and the proportion of patients receiving timely follow-up. The hypotheses that the development of QI infrastructure indirectly affects timely follow-up through improvements-to-care processes and/or increases in gastroenterology capacity are assessed, and the relationship between facility-reported barriers to improvement and timely follow-up is examined. Methods Data Sources and Measures Key variables in these analyses were obtained from two sources: (1) a survey of VA medical centers that assessed activities to improve the timely follow-up of positive FOBTs and identified perceived barriers to improvement; and (2) a VA performance monitor that included facility self-reported rates of 60-day follow-up of patients with positive FOBT results. Medical center survey In June 2007, a web-based survey was completed by 95% of VA medical centers (n=132) on their FOBT follow-up quality improvement activities. The survey instrument was developed by a committee of VA researchers, clinical experts, and administrative leadership and was pre-tested at six VA facilities. The survey was completed by the staff member most familiar with their facility's current positive-FOBT follow-up improvement activities. Participants were asked to indicate the degree to which their facility had implemented each of 16 strategies to improve follow-up of positive FOBTs. The list of strategies was identified from a 2006 survey of 21 VA facilities participating in a pilot project to improve the timeliness of positive-FOBT follow-up. Participants indicated whether each strategy had been fully implemented, partially implemented, never implemented, or previously implemented but no longer in use. To assess predictors of timely follow-up, responses were transformed into dichotomous variables (fully implemented=1, all other responses=0). After the data were collected, strategies were classified into three general categories (Table 1). Strategies designed to identify problems, organize resources to focus on improvement, or measure the effect of system change were classified as development of QI infrastructure. Strategies that involved modifications to the care delivery system were classified as process changes. Attempts to increase gastroenterology resources were classified as gastroenterology capacity building. Variables were created representing these three categories by adding the number of items that had been fully implemented by each facility within each category. | | |  | Improvement strategy | Fully implemented | In the process of implementing | Have not implemented | Implemented in the past but no longer use | |
|---|
| Development of QI infrastructure | | | | | |  Track colonoscopy supply and demand | 56 | 28 | 12 | 4 | | | Form an active multidisciplinary improvement team | 56 | 22 | 19 | 2 | | | Participate in an improvement collaborative | 51 | 21 | 28 | 1 | | | Create system for tracking follow-up of +FOBTs | 42 | 38 | 20 | 0 | | | Track number of inappropriate FOBTs | 33 | 28 | 37 | 2 | | | Track number of incomplete colonoscopies | 28 | 20 | 48 | 4 | | | Process changes | | | | | | | Strategies to decrease cancellations/no-shows | 82 | 12 | 5 | 1 | | | Create/revise primary care/gastroenterology service agreement | 64 | 22 | 11 | 4 | | | Consult template revision | 59 | 25 | 15 | 1 | | | Revise colonoscopy prep education/protocols | 54 | 21 | 24 | 1 | | | Revise CRC screening clinical reminder | 43 | 31 | 26 | 0 | | | Gastroenterology capacity building | | | | | | Initiate/increase use of fee-based colonoscopies | 44 | 16 | 35 | 5 | | | Hire additional nurses/other staff | 29 | 33 | 37 | 1 | | | Hire additional colonoscopists | 23 | 35 | 42 | 0 | | | Contract additional onsite colonoscopists | 15 | 18 | 65 | 2 | | | Add additional endoscopy suites | 15 | 27 | 55 | 3 | | | | |
Responses to an open-ended survey question, What have been the most significant barriers to improvement? were coded independently by two coders (Kappa=0.97). Ten response categories were mentioned by seven or more facilities (>5%) and were included in analyses. FOBT follow-up performance monitor In 2006, the VA implemented an FOBT follow-up performance monitor that required facilities to flow-chart their FOBT follow-up process, initiate improvement efforts, and report data on the timeliness of positive-FOBT follow-up. As part of this monitor, in October 2007, facilities reported the number of patients receiving a positive CRC screening FOBT lab result between March and June 2007 and, of those tracked, the number receiving a colonoscopy within 60 days of the FOBT lab result. (Although facilities were not given explicit instructions regarding tests completed through digital rectal exam, VA guidelines consider this method unacceptable for CRC screening.) Data were reported by 133 (96%) medical centers, including 125 facilities that had completed the July 2007 medical center survey. Analysis The facility 60-day positive-FOBT follow-up rate is presented (median and interquartile range), as well as frequency distributions indicating the degree to which each improvement strategy was implemented. To assess which if any of the improvement strategies predicted timely FOBT follow-up, each of the dichotomous improvement-strategy variables was entered into separate regression models using the percent of positive-FOBT patients receiving 60-day follow-up as the dependent variable. Models were also created using the total number of strategies fully implemented by each medical center and each of the dichotomous barriers to improvement variables as independent variables. Two hypotheses regarding the relationship between the implementation of QI infrastructure strategies and 60-day follow-up were tested: (1) that this relationship is mediated through the implementation of process-change strategies; and (2) that this relationship is mediated through the implementation of gastroenterology capacity building strategies. For each hypothesis, Baron and Kenny's three-step regression procedure was used to ascertain the relationships between a proposed independent, dependant and mediator variable.14 In the first step, the dependent variable was regressed on the independent variable to determine if there was a relationship to explain. Second, to ascertain whether the independent variable was associated with the proposed mediator, the mediator variable was regressed on the independent variable. Third, the dependent variable was regressed on both the mediator and the independent variable. This assessed whether the mediator was associated with the dependent variable while controlling for any direct effect of the independent variable. This third regression also assessed the direct (unmediated) effect of the independent variable on the dependent variable. In addition to conducting this three-step analysis, the significance of the mediated path was tested.15, 16 All models were first developed using linear least squares regression analysis; however, the error terms of some models were not normally distributed. Parameters of each model were therefore also estimated using bootstrapping techniques, which are robust to nonnormality.17 This computational method involves resampling the data multiple times to generate a mean estimate of coefficients and confidence intervals. Both bootstrapped and nonbootstrapped results were very similar. Bootstrapped unstandardized beta coefficients and 95% CIs are reported. The unstandardized beta coefficient quantifies the change in the dependent variable attributed to one unit change in the independent variable. Although five variables were initially considered for inclusion as covariates in the regression models—number of clinical gastroenterology staff, number of total gastroenterology staff, number of outpatients seen by the facility, median patient age, and median patient income—only the number of clinical gastroenterology staff was associated with the 60-day follow-up dependent variable. However, data on this measure were unavailable for 26 facilities. Analyses conducted on facilities with complete data on gastroenterology staffing indicated that controlling for this measure had little effect on the results and did not alter our conclusions. Therefore, the results presented here do not control for this factor. All analyses were conducted in R version 2.7.1 with the exception of the bootstrapped mediation analyses which were generated in SAS version 9.1 with macros created by Preacher and Hayes.18 Results The median facility-reported 60-day follow-up rate for patients receiving positive FOBT lab results between March and June 2007 was 24.5% (interquartile range=13.8% to 40.7%). Table 1 depicts the degree to which each of the 16 change strategies had been implemented at VA facilities. Strategies to decrease cancellations or no-shows and to create/revise primary care/gastroenterology service agreements were most common. The effect of each improvement strategy on the timely follow-up of positive FOBTs is reported in Table 2. | | | | Improvement strategy (fully implemented versus any other response) | β (95% CI) | |
|---|
| DEVELOPMENT OF QI INFRASTRUCTURE | | | | Track colonoscopy supply and demand | 8.5(0.7to16.4) | | | Form an active multidisciplinary improvement team | 7.2(−0.3to14.7) | | | Participate in an improvement collaborative | 5.6(−1.9to13.2) | | | Create system for tracking follow-up of +FOBTs | 7.7(0.3to15.1) | | | Track number of inappropriate FOBTs | 2.0(−6.6to10.6) | | | Track number of incomplete colonoscopies | 5.8(−2.5to15.1) | | | PROCESS CHANGES | | | | Strategies to decrease cancellations/no-shows | 7.9(0.1to15.7) | | | Create/revise primary care/gastroenterology service agreement | 11.2(4.2to18.3) | | | Consult template revision | 5.1(−1.5to11.8) | | | Revise colonoscopy prep education/protocols | 10.6(3.9to17.4) | | | Revise CRC screening clinical reminder | 7.6(−0.2to15.4) | | | GASTROENTEROLOGY CAPACITY BUILDING | | | | Initiate/increase use of fee-based colonoscopies | 1.3(−6.7to9.2) | | | Hire additional nurses/other staff | 7.8(−.2to15.7) | | | Hire additional colonoscopists | 4.9(−4.2to14.0) | | | Contract additional onsite colonoscopists | 3.5(−7.1to14.0) | | | Add endoscopy suites | 3.7(−7.5to14.9) | | | | |
Strategies that were significantly associated with timely follow-up include two strategies to develop QI infrastructure and three process-change strategies. Additionally two QI infrastructure strategies and one gastroenterology capacity strategy approached significance. On average, facilities indicated that they had fully implemented 6.84 improvement strategies. The total number of strategies fully implemented was positively associated with 60-day follow-up (β=1.9, 95% CI=0.9, 3.0). Results of two mediation analyses are depicted in Figure 1. The hypothesis that the effect of QI infrastructure on timely follow-up is mediated by process changes was supported. The number of QI infrastructure strategies implemented significantly predicted timely FOBT follow-up (Path a, β=2.9, 95% CI=0.6, 5.2). The QI infrastructure variable also predicted the number of process-change variables implemented (Path bprocess, β=0.36, 95% CI=0.24, 0.48). When timely follow-up was regressed on both QI infrastructure and process-change variables, the effect of process change was significant (Path cprocess, β=4.0, 95% CI=1.8, 6.3) but the effect of QI infrastructure was no longer significant (Path a′process, β=1.8, 95% CI=−0.5, 4.0). The coefficient associated with the mediated path was significant (Path bcprocess, β=1.2, 95% CI=0.3, 2.6). The hypothesis that the effect of QI infrastructure on timely follow-up is mediated by changes in gastroenterology capacity was not supported. The first mediation analysis had already established that QI infrastructure predicted timely follow-up (Path a). QI infrastructure also predicted the number of gastroenterology capacity changes implemented (Path bcapacity, β=0.17, 95% CI=0.05, 0.28). However, when timely follow-up was regressed both on QI infrastructure and gastroenterology capacity, the relationship between capacity and timely follow-up was not significant (Path ccapacity, β=2.4, 95% CI=−0.4, 5.3) and the relationship between QI infrastructure and timeliness remained significant (Path a′capacity, β=2.7, 95% CI=0.4, 5.0). Additionally the mediated path coefficient was not significant (Path bccapacity, β=0.3, 95% CI=−0.2, 1.1). Table 3 displays commonly mentioned barriers to timely FOBT follow-up, their frequency of mention, and the relationship between each barrier and 60-day follow-up. The most commonly sited barrier to improvement was the number of endoscopists on staff. The second and third most commonly mentioned barriers also concerned limitations in gastroenterology capacity (number of non-endoscopist staff and gastroenterology clinic space issues). Facilities that mentioned either the number of endoscopists or the number of non-endoscopist staff as a barrier had a significantly lower rate of FOBT follow-up than those that did not. | | | | Barrier | Number mentioning | β (95% CI) | |
|---|
| CAPACITY-RELATED BARRIERS | | | | | Number of endoscopists | 55 | −9.4(−17.6,−1.2) | | | Number of non-endoscopist staff | 35 | −9.3(−15.5,−3.1) | | | Number of procedure/recovery rooms | 33 | −1.4(−10.2,7.5) | | | Resource/staff limitations (type not specified) | 19 | −1.5(−12.4,9.3) | | | Fee basis limitations | 10 | −5.4(−17.2,6.4) | | | OTHER BARRIERS | | | | | Patient cancellations/no-shows | 19 | 3.7(−7.9,15.3) | | | Tracking/record keeping problems | 21 | 8.8(−2.3,20.0) | | | Poor primary care/gastroenterology communication | 10 | 1.8(−9.1,12.8) | | | Patient travel issues | 9 | 18.5(−2.6,39.6) | | | Inappropriate FOBTs | 8 | −5.3(−15.8,5.2) | | | | |
Discussion The VA's adoption of a CRC screening performance measure and clinical reminder system has led to substantial increases in VA screening rates, primarily through the extensive use of FOBTs.3 As a result, VA patients are more likely to be screened for CRC than are individuals covered by commercial, Medicare or Medicaid plans.19 However, this increase in FOBT screening has led to a downstream increase in the demand for colonoscopies following positive screens. Results of this study suggest that the benefit to veterans of the VA's high screening rate may be limited by lower rates of timely follow-up. Only one in four patients received follow-up colonoscopies within 60 days of a positive FOBT lab result. Other studies with follow-up windows ranging from 6 to 12 months have documented CRC screening follow-up rates of 34 to 65%.8, 10, 20, 21, 22 Improving Timely FOBT Follow-Up There does not appear to be a single “silver bullet” for improving timely follow-up of positive FOBTs. Several improvement strategies that were implemented by VA facilities significantly predicted the proportion of patients receiving timely follow-up. These include two QI infrastructure strategies (tracking colonoscopy supply and demand and creating a system for tracking follow-up of +FOBTs) and three process-improvement strategies (creating/revising primary care/gastroenterology service agreement, revising colonoscopy prep education protocols, and decreasing cancellations and/or no-shows). These strategies, either individually or in combination, should be considered in the development of future interventions to improve the timeliness of positive-FOBT follow-up. Additionally these results suggest that the percent of patients receiving timely follow-up may be partially a function of the total number of improvement strategies implemented. The hypothesis that the implementation of process changes mediates the relationship between the development of QI infrastructure and timely FOBT follow-up was supported. Creating QI infrastructure takes substantial resources, especially if collecting the necessary data for tracking events and outcomes is not easily automated. This research suggests that in order for the development of QI infrastructure to translate into improvement there must be enough resources remaining and enough tension for continued change so that the infrastructure created is used to facilitate the implementation of process changes. By planning up front for work beyond the development of QI infrastructure, there is a greater chance that efforts will lead to improvement. The hypothesis that the relationship between QI infrastructure and timely follow-up would be mediated by the implementation of strategies to increase gastroenterology capacity was not supported. One possible reason for this is that although a strong QI infrastructure may help in identifying what type of additional gastroenterology clinic resources are needed, a facility's ability to obtain these additional resources may be unrelated to QI infrastructure. Instead changes in gastroenterology capacity are more likely to be a function of the facility's capital planning process, available funds, and the local labor pool for appropriate staff (e.g., gastroenterology physicians and nurses). Another possibility is that process changes have greater potential for impact than increases in capacity. Research on delay in healthcare systems suggests that access limitations are more frequently the result of suboptimal management of current capacity than insufficient levels of capacity.23, 24 A third possibility is that the medical centers that were the poorest performers to start with were more likely to allocate financial resources to increasing gastroenterology capacity. A single-point measure of timely positive-FOBT follow-up is unable to account for any such variations in baseline performance. Barriers to Improvement The most commonly cited barriers to improvement involved capacity constraints. Sites listing insufficient gastroenterology staff as a barrier had a lower percent of patients receiving timely follow-up than those that did not. One interpretation of this finding is that higher performing facilities have adequate staff to meet their demand for colonoscopies. It is also possible that some facilities believe that long waits for colonoscopies are unavoidable because their gastroenterology clinic is understaffed. This belief may keep these facilities from attempting to identify and implement process improvements. The fact that none of the improvement strategies designed to address gastroenterology capacity constraints were associated with timely follow-up suggests that this barrier may be more difficult or take more time to address than process inefficiencies. Limitations Data on timeliness of follow-up were self-reported by facilities. Data definitions and the completeness of reporting may have varied across sites. If inaccuracies in these self-reports varied systematically between facilities that did and did not fully implement a system to track positive FOBTs, the reported association between fully implementing a positive-FOBT tracking system and timeliness of follow-up may be spurious. It should be noted however that although 20% of facilities indicated that they had not fully implemented a positive-FOBT tracking system, all facilities included in this analysis had, at a minimum, developed a means of obtaining positive-FOBT follow-up data for the 4-month FOBT follow-up performance monitor reporting period. A second limitation is that because data on implementation strategies were collected in June of 2007 and 60-day follow-up data were collected on patients with positive FOBT results between March and June of 2007, it is possible that some implemented strategies had not been in place long enough to affect 60-day follow-up rates. A third limitation is that no information was obtained on the context in which improvement strategies were implemented. Contextual factors may play a critical role in determining each strategy's success. Fourth, this work does not assess the relationship between rates of 60-day follow-up and clinical or psychological outcomes. Further research is necessary to examine this issue. Finally, because the strategies implemented were measured but not manipulated, this research does not provide definitive evidence of the effectiveness of each strategy. This work does however identify several specific strategies that were associated with improvement. Perhaps more importantly, this work suggests a framework for the creation of improvement programs in which initial efforts are focused on the development of QI infrastructure and are then followed by targeted strategies designed to improve processes of care. We would like to express our appreciation to George Ponte, George Jackson, Dawn Provenzale, Heidi Martin, David Haggstrom, Emily Bliss, and Janice Hersh for their help in the development of the data-collection instruments used in this study. Additionally we thank all VA staff members that were involved in the CRC diagnosis quality improvement project for their hard work and cooperation with this research. 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24. 24Murray M, Tantau C. Same day appointments: exploding the access paradigm. Fam Pract Manag. 2000;7:45–50. MEDLINE a Center for Chronic Disease Outcomes Research, Veterans Affairs Medical Center, Minneapolis, Minnesota b Veterans Affairs Office of Quality and Performance, Washington, DC c Edith Nourse Rogers Memorial Veterans Hospital, Bedford, Massachusetts  Address correspondence and reprint requests to: Adam A. Powell, PhD, MBA, Center for Chronic Disease Outcomes Research (CCDOR), One Veterans Drive (111-0), Minneapolis MN 55417
PII: S0749-3797(09)00294-3 doi:10.1016/j.amepre.2009.05.013 Published by Elsevier Inc. | |
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