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Although colorectal cancer (CRC) prognosis is improved by early diagnosis, screening rates remain low.
To determine the effect of an automated telephone intervention on completion of fecal occult blood testing (FOBT).
In this randomized controlled trial conducted at Kaiser Permanente Northwest, a not-for-profit health maintenance organization, 5,905 eligible patients aged 51–80, at average risk for CRC and due for CRC screening, were randomly assigned to an automated telephone intervention (n=2,943) or usual care (UC; n=2,962). The intervention group received up to 3 one-minute automated telephone calls that provided a description and health benefits of FOBT. During the call, patients could request that an FOBT kit be mailed to their home. Those who requested but did not return the cards received an automated reminder call.
Cox proportional hazard method was used to determine the independent effect of automated telephone calls on completion of an FOBT, after adjusting for age, gender, and prior CRC screening.
By 6 months post call initiation, 22.5% in the intervention and 16.0% in UC had completed an FOBT. Those in the intervention group were significantly more likely to complete an FOBT (HR = 1.31, 95% CI = 1.10–1.56) compared to UC. Older patients (aged 71–80 vs. aged 51–60) were also more likely to complete FOBT (HR = 1.48, 95% CI=1.07–2.04).
Automated telephone calls increased completion of FOBT. Further research is needed to evaluate automated telephone interventions among diverse populations and in other clinical settings.
Colorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer-related death in the United States (1). In 2009, CRC will be newly diagnosed in about 112,340 people, resulting in over 52,180 deaths (2). Total direct costs associated with treating CRC are $17 billion, with 9.8 million work days lost annually to hospitalization for colon cancer (2).
The early detection of high-risk lesions or CRC through appropriate screening is associated with decreased incidence and mortality from CRC (3–5). The US Preventive Services Task Force (USPSTF) recommends that men and women of average risk begin screening for CRC starting at age 50 (6), and specialty care guidelines provide recommendations for higher-risk groups (7). Among the currently recommended CRC screening modalities for average-risk patients, only routine fecal occult blood testing (FOBT) has been evaluated in the context of a randomized clinical trial for reducing CRC mortality.
Despite the benefits of CRC screening, it is estimated that only 50–60% of adults aged 50 and older receive screening tests at recommended intervals (8–14). Moreover, rates for CRC screening are substantially lower than for other types of recommended cancer screening (9) and there is a need to enhance CRC screening efforts (15).
Telephone reminder calls using live callers were effective in prompting adults eligible for CRC screening to complete needed tests (16–18,20–22,24) Interventions ranged from simple telephone reminder calls to intensive personalized messaging, including targeted and tailored contacts delivered by telephone and mail (20–22) to reduce screening barriers. Although successful, live-caller interventions to increase CRC screening are often expensive and resource-intensive. In contrast, automated-call interventions offer a low-cost method for delivering CRC screening messages and may be more sustainable in a variety of healthcare delivery systems. We sought to determine the effect of an automated telephone contact campaign on completion of FOBT, an evidence-based screening method for populations with average risk for CRC.
The protocol for this study was approved by the institutional review board within the study health maintenance organization (HMO). The need for individual signed consent was waived.
The study was conducted in 2008 at Kaiser Permanente Northwest (KPNW), a nonprofit group-model HMO operating in southern Washington and northern Oregon, consisting of 15 medical clinics and about 485,000 members. At the time of the study FOBT was the recommended method of screening for those with average risk of CRC within KPNW.
KPNW member demographics (age, gender, race/ethnicity) are similar to those of the area population. KPNW regional electronic databases provided data on patient membership, demographics, primary care assignment, clinical data including weight and height, laboratory results, and other healthcare utilization, including CRC screening. These data capture over 95% of all medical care and pharmacy services that members receive, and data are linked through each member’s health record number.
Figure 1 outlines the study design and participant flow during the trial. Our goal in participant selection was to identify an age-eligible population at average risk for developing CRC, for whom CRC screening using FOBT was both appropriate and due. The rationale for selecting FOBT as the primary CRC screening method was based on the USPSTF report that FOBT is the only evidence-based CRC screening test for those with average CRC risk. Secondly, based upon prior organizational-use trends, the investigators and KPNW clinical experts felt that encouraging FOBT (at a minimum, even if patient also later chose to have endoscopy) was likely to be acceptable to the largest number of people.
We first identified HMO members aged 51–80 who did not have any of the following: 1) colonoscopy within 10 years, 2) flexible sigmoidoscopy or double-contrast barium enema (DCBE) within 5 years, 3) FOBT screening within the past 12 months, or 4) a clinician order or referral for FOBT or DCBE in the past 3 months (n=45,558). We then excluded a total of 6,063 patients because of medical conditions that suggested they were inappropriate for CRC screening through FOBT. These included: 1) active CRC/GI risk factors (n=4,261) in the previous 12 months (referral for chronic diarrhea, esophageal reflux, iron deficiency, polyp follow-up/rectal surgery, diagnosis of adenomatous polyps, diagnosis of HIV/AIDS, or referral for colonoscopy or sigmoidoscopy in the past 3 months); 2) use of medications (n=174) in the previous 4 months (plavix, warfarin) that elevated the risk of a false positive FOBT; or 3) other medical conditions (n=1,628) for which routine screening was not indicated (end-stage renal disease, hospice care, receipt of total colectomy). Of the remaining 39,495 individuals, 7,175 were excluded because continuous medical coverage was not maintained for the minimum duration of 2 years prior to randomization. This left a total eligible patient population of 32,320. We then randomly selected 6,000 of these patients for study participation.
We conducted a randomized clinical trial (RCT) with randomization at the patient level. The 6,000 patients were randomly assigned either to receive usual care (UC) (n=3,000) or automated telephone contacts (n=3,000), using a stratified randomization approach, balancing on age, gender, and prior CRC screening. After randomization but prior to the start of the intervention, 38 patients in UC and 57 patients in the intervention group had either disenrolled from the HMO or received CRC screening. These patients were excluded from the primary analyses.
The general automated call (call type 1) lasted about 1 minute and provided a brief overview, including information about the benefits of CRC screening, and encouraged FOBT as a relatively simple and low-risk method of cancer screening. Recipients could request FOBT cards by pressing a number via touch-tone telephone. If a live person did not answer, callers heard a detailed message with a telephone number they could call to request cards. Patients who did not complete FOBT screening received up to two reminder calls, 6 weeks apart. Call content was identical to the first automated telephone call. Call scripts were developed in close collaboration with KPNW quality improvement and care management staff.
One additional reminder call was targeted to intervention participants who had requested an FOBT kit but did not return the completed FOBT cards within 4–5 weeks from the date of request. The call to non-returners (call type 2) emphasized the benefits of CRC screening and reminded patients to return completed FOBT cards. Patients were given the opportunity to request additional FOBT cards if needed.
Patients randomized to usual care did not receive the telephone contact intervention but may have been referred for CRC screening by their clinicians during normal care processes. KPNW clinicians have access to national guidelines, Intranet-based screening guidelines (available since November 9, 2007), and KPNW’s “panel support tool,” an electronic prompt system embedded in the electronic medical record that informs physicians which patients are overdue for preventive services (including CRC screening) at primary care visits and prompts physicians to order needed services.
The primary outcome measure was completion of FOBT during the 6 months after call initiation. FOBT screening used the guaiac method, which required samples from three consecutive stools. The secondary outcome was screening through any USPSTF-recommended CRC screening modality during the RCT and included: receipt of FOBT, colonoscopy, flexible sigmoidoscopy, or DCBE.
Explanatory variables included: age (51–60, 61–70, 71–80), gender, prior CRC screening status (yes, no, for whether the patient had ever been screened by any method at study site), race/ethnicity (white, non-white, unknown), primary care provider assignment (yes, no), obesity status (yes, no, unknown) and receipt of prior CRC reminder calls (yes, no). Receipt of prior CRC reminder calls included whether a prior automated call was sent to the study population. As part of an ongoing quality improvement effort, eligible patients overdue for CRC screening received similar automated messages as the study population in the RCT. Automated calls began 4 months prior to the initiation of the RCT, included 1 automated call, and did not target non-responders. Age was assessed upon randomization, while race/ethnicity was available at the individual level for 60% of patients, with the remainder being geo-coded (19). Obesity status was defined as body mass index (BMI) > 30, if height and weight were available, or > 250 pounds if height was not available. Height and weight values were collected as close to the call-initiation date as possible or within a window of 60 months before and 5 months after call initiation. Primary care utilization (% > 1 visits) was also measured six months post call initiation.
Based on the sample size of 6,000, we had 80% power to detect an absolute difference of 2.8% (relative difference of 28.6%), assuming the FOBT return rate was 9.7% in UC vs. 12.5% in the intervention group. We used Cox proportional hazard models for the primary analysis of time until completion of FOBT, in days, during the 6-month follow-up period. Group (automated telephone call vs. usual care group) was the primary independent variable of interest. The association between completion of FOBT with other factors–age, gender, prior receipt of CRC screening, race/ethnicity, whether or not the patient had a primary care provider-assigned obesity status, and receipt of prior CRC screening reminder call–were tested with bivariate Cox proportional regression models. Significant associations (p<.10) were included in the final model as covariates. In addition, we examined whether the intervention effect differed across age groups, gender, and prior CRC screening by testing interaction terms with the intervention group. Interactions with the intervention group were selected to better understand whether subgroups respond differently from one another.
The final Cox model included: 1) intervention status (usual care [reference group] vs. CRC automated telephone contact group); 2) age (51–60 [reference group] vs. 61–70, 71–80); 3) age x intervention interaction term (intervention x age 51–60 [reference group] vs. intervention x 61–70, intervention x 71–80); 4) gender (male [reference group] vs. female) and 5) prior receipt of CRC screening (no [reference group] vs. yes).
Table 1 presents the baseline characteristics for the CRC reminder population (intervention group) and usual care group. No statistically significant differences were found between the two populations for any of the baseline characteristics. The mean age was about 60 years. There were nearly equal proportions of men and women, and about 92% were white. Nearly 40% were considered obese. Lastly, about 30% in each condition had ever received any prior CRC screening, nearly 90% were assigned to a primary care provider (PCP), and a similar proportion of each group had received one prior CRC screening reminder call (intervention group = 13.4%, vs. usual care = 12.4%). Nearly 50% in each group had 1+ primary care visits, 6 months post call initiation.
By 6 months post call initiation, 22.5% in the intervention vs. 16.0% in the UC group had completed FOBT, and 23.9% in the intervention vs. 17.6% in the UC group had completed any CRC screening method (results not shown). Of the total intervention group, 2,943 (100%) received the initial call type 1 (general reminder), 2,406 (81.8%) received 2 calls of type 1, and 1,632 (55.5%) received 3 calls of type 1 (results not shown). Of those that received general reminder calls, 488/2,943 (16.6%) requested stool cards on the first reminder; 290/2,406 (12.1%) requested them on the second call; and 85/1,632 (5.2%) did so on the third general call. Call type 2 (FOBT return reminder) was administered to 18.3% (540/2,943) of the intervention group.
Figure 2 shows the unadjusted time-to-completion of FOBT curves for both study groups. Overall, a larger proportion of the intervention group completed FOBT over time. This effect appears to begin at about 8 weeks. After maximum effect at about 12–14 weeks, there does not appear to be much additional intervention effect, with study group lines becoming and remaining parallel until the end of the observation period. In the unadjusted model, the intervention group was 1.48 times more likely (95% CI 1.31–1.66) to complete the test than the UC group (p<.001). Completion of FOBT did not vary by gender (p=.066), race/ethnicity (p=.724), whether or not the patient had an assigned primary care physician (p=.221), obesity status (p=.108), or receipt of prior CRC automated telephone call (p=.373), but was associated with age (p<.001) and prior screening (p<.001). Only the interaction of age and intervention group was significant (p=.018).
Table 2 presents the multivariable Cox proportional hazards models predicting time until FOBT. After adjusting for the other variables in the model, those in the CRC reminder group were 1.31 times more likely (95% CI = 1.10–1.56, p <0 .001) to complete an FOBT, compared to those in usual care. Receipt of prior CRC screening was also strongly associated (H.R. = 2.68; 95% CI = 2.37–3.02; p <0.001) with completion of FOBT screening, when compared to no prior CRC screening. The significant group-by-age interaction revealed that the 71–80-year-old group was also more likely to respond to the intervention than the 51–60-year-old group (H.R. = 1.48; 95% CI = 1.07–2.04; p =0.02). Using any CRC screening (including all modalities) as an outcome measure did not substantively change these results.
In additional analysis (results not shown), after removing adults aged 76–80 from the final Cox model, those aged 71–75 were more likely to complete FOBT (HR = 1.56 95% CI =1.16–2.08) than were younger adults aged 51–60. Moreover, the overall effect of intervention (CRC reminder call vs. usual care) remained significant, even after removing the population age 71+ (HR = 1.31 95% CI = 1.10 – 1.56).
We found that an automated telephone contact intervention for FOBT screening was effective in increasing CRC screening when compared to usual care in a population aged 51–80 at average risk for CRC. At 6 months, FOBT screening rates were 22.5% in the intervention group and 16.0% for UC. The intervention increased the likelihood of FOBT screening by about 30%, markedly so for patients aged 71–80 compared to those aged 51–60. Although statistically significant, the effect size of the intervention was modest in that less than 25% of the intervention population completed FOBT.
Our study findings are consistent with previous research that reported positive effects of telephone contact interventions. Previous studies have found that telephone contact interventions using live callers were associated with increased screening for CRC (16–18;20–22,24) and breast and cervical cancers (19,23–26). These interventions are least effective when using telephone contact alone (OR = 1.7–1.9), (24–25) and most effective when using targeted and tailored contacts by telephone and mail (OR = 1.9–4.4), (20,22).
This study is the first randomized trial to examine the effect of an automated telephone contact intervention with CRC screening. Only one other study has evaluated the use of automated calls to improve cancer screening in a similar population overdue for screening: Feldstein (27) found that automated telephone calls after a reminder mailing and followed by a live call for non-responders were effective in increasing use of mammography, compared to usual care (HR 1.51; 95% CI = 1.40–1.62). In this study, an informational postcard was sent prior to delivery of automated calls, and live-callers were used to schedule mammography for non-responders. The multi-modal approach of this intervention may explain the stronger effect size, compared to results found in our study (HR 1.31; 95% CI = 1.10–1.56). The automated call content regarding mammography was similar to the message regarding FOBT delivered in our study. In both studies, respondents were informed of the importance of screening and encouraged to complete screening.
The main finding—that simple automated telephone calls can increase use of FOBT screening—has large implications for real-world medical practices. These types of patient calls could be implemented in a variety of delivery systems. Moreover, the effect size of the intervention may be even stronger in delivery systems that do not have other active system interventions, such as the clinician electronic visit-based CRC screening prompts at this study site (KPNW).
Although this study did not include a formal cost-effectiveness analysis, automated telephone contact interventions are relatively inexpensive compared to live-person telephone-contact interventions. Live-person interventions are often labor-intensive and require hiring telephone staff for implementation. Conversely, automated telephone contact interventions do not require telephone-based staff and are much less resource-intensive. These less-costly interventions can be delivered through public delivery systems, which are often constrained for resources. Moreover, because the intervention’s maximum effect occurs by 12–14 weeks, automated reminder campaigns do not need to be lengthy, which further reduces delivery costs.
Of particular interest was the finding that individuals aged 71–80 were most likely to complete a FOBT in response to automated telephone calls, compared to younger individuals (aged 51–60). Supporting our findings, a recent study that evaluated telephone-based motivational interviewing followed by telephone reminder calls also found that older individuals were more responsive to mailed reminders for CRC screening (21;22). While our study did not isolate the reasons for such higher responsiveness, we hypothesize that older individuals are more receptive to the intervention because they are more sensitive to their increased risks for CRC; furthermore, older people are generally home more often to receive calls.
For two reasons, the responsiveness of older participants (ages 71–80) remains important, despite the recent USPSTF guidelines recommending against CRC screening for populations between ages 76–85. First, the USPSTF recommendation was based on life expectancy concerns and time needed to benefit from screening but didn’t largely apply to this study population, since fewer than 10% of participants were 76–80. Second, the intervention was equally effective even after removing individuals age 76–80.
Interestingly, while both Rosen (28) and Ferrante (29) found that obese patients were less likely to complete FOBT screening, our research demonstrated that obesity was not associated with completion of FOBT. It is unclear why our findings differed; more research is needed to fully understand the effect of obesity status on completion of FOBT and CRC screening.
Finally, we found that baseline CRC screening status did not interact with the intervention group. This suggests that the automated messages may be effective for previously unscreened patients and in encouraging repeat CRC screenings. More research is needed to understand what best facilitates a pattern of routine screening.
Although we found increased use of FOBT after implementation of the intervention in KPNW, national trends suggest that colonoscopy is being used over FOBT (8). Given this trend, we believe that aspects of this automated telephone intervention could be applied to facilitate scheduling of colonoscopy. Feldstein (27) found that automated telephone reminder calls resulted in increased mammography use.
This study is not without limitations. First, the magnitude of the results may not be generalizable beyond a group-model HMO setting or populations without telephones. However, notwithstanding this limitation, study results are likely applicable to other delivery systems, given that automated reminder calls are a simple direct-to-patient intervention. Second, the study included few racial/ethnic minorities, which precluded our ability to assess differences in FOBT screening by race/ethnicity. However, the study population was representative of the KPNW population, which is predominantly white, and most members (99%) have telephones. Nevertheless, implementation of automated telephone interventions may have generalizability concerns, since certain sub-populations, such as African-Americans and Hispanics, are more likely to not have telephones compared to the overall U.S. population (30).
Findings from this research suggest several additional areas for future research. First, work is needed to implement and evaluate automated CRC telephone contact interventions in a variety of public and private delivery systems. Second, more research is needed to better understand provider and patient characteristics associated with non-completion of FOBT or alternatively a pattern of routine screening. Moreover, given the modest effect size, further methods are needed to strengthen the intervention, perhaps by combining mailings and/or live calls, or switching to a fecal test that is easier to use, such as the fecal immunochemical test (FIT).
Last, given advancements in communication technologies, alternative methods for delivering screening reminders, such as e-mail and text messaging, should be tested, especially in younger populations.
We found that an automated telephone contact intervention was effective in increasing CRC screening using FOBT in a population aged 51–80 at average risk of CRC, when compared to usual care. The direct-to-patient aspect of automated telephone contact interventions has the potential to increase CRC screening rates in a variety of public and private delivery systems.
We would like to thank the following individuals whose contributions made this research possible: Gail Morgan, Dixie Sweo, Mary Rix, Kara Keel, Heather Block, Stephanie Schoap, Maureen Wright, Mike Lassi, and Andre Smith.