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Selected states, 2003 to 2004
Article first published online: 21 DEC 2007
Published 2007 American Cancer Society
Volume 112, Issue 3, pages 626–635, 1 February 2008
How to Cite
Ekwueme, D. U., Gardner, J. G., Subramanian, S., Tangka, F. K., Bapat, B. and Richardson, L. C. (2008), Cost analysis of the National Breast and Cervical Cancer Early Detection Program. Cancer, 112: 626–635. doi: 10.1002/cncr.23207
This article is a US Government work and, as such, is in the public of main in the United States of America.
The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
- Issue published online: 18 JAN 2008
- Article first published online: 21 DEC 2007
- Manuscript Accepted: 21 AUG 2007
- Manuscript Revised: 17 AUG 2007
- Manuscript Received: 1 MAY 2007
- cost analysis;
- National Breast and Cervical Cancer Early Detection Program;
- breast cancer;
- cervical cancer;
The National Breast and Cervical Cancer Early Detection Program (NBCCEDP) was established by the U.S. Congress in 1990. In recent years, there has been an emphasis on ascertaining the NBCCEDP's costs of delivering screening and diagnostic services to medically underserved, low-income women. The objective of this report was to address 3 economic questions: What is the cost per woman served in the program, what is the cost per woman served by program component, and what is the cost per cancer detected through the program?
The authors developed a questionnaire to systematically collect activity-based costs on screening for breast and cervical cancer from 9 participating programs. The questionnaire was developed based on well established methods of collecting cost data for program evaluation. Data were collected from July 2003 through June 2004.
With in-kind contributions, the cost of screening services to women in 9 programs was estimated at $555 per woman served. Without in-kind contributions, this cost was $519. Among the program components, screening and coalitions/partnerships accounted for the highest and lowest cost per woman served, respectively. The median cost of screening a woman for breast cancer was $94, and the cost per breast cancer detected was $10,566. For cervical cancer, these costs were $56 and $13,340, respectively.
Costs per woman served, screened, and cancers detected are needed for programs to accurately determine the resources required to reach and screen eligible women. With limited program resources, these cost estimates can provide useful information to assist programs in planning and implementing cost-effective activities that could maximize the allocation of program resources. Cancer 2008. Published 2007 by the American Cancer Society
In the U.S., both breast cancer and cervical cancer impose considerable health and economic burdens on society and on individuals who are diagnosed with these diseases. According to data from the U.S. Cancer Statistics in 2003, an estimated 181,646 American women were diagnosed with breast cancer, and 41,619 women died from it; for cervical cancer, the estimates were 11,820 women diagnosed and 3919 deaths.1 Many of these deaths are preventable with screening using mammography for breast cancer and the Papanicolaou (Pap) test for cervical cancer.
Despite their acceptability and widespread availability, these screening methods may not be affordable to low-income women. Because uninsured, low-income women may not be able to afford screening, they may lose the benefits of early detection and treatment that, in the case of cervical cancer, also may include prevention.
In response to the lack of affordability of screening and follow-up and the disproportionate burden of breast and cervical cancer borne by uninsured, low-income women, in 1990, the U.S. Congress passed the Breast and Cervical Cancer Mortality Prevention Act, (Public Law 101–354, Title XV, Public Health Service Act).2 This law established the National Breast and Cervical Cancer Early Detection Program (NBCCEDP), which is administered by the U.S. Centers for Disease Control and Prevention (CDC). The NBCCEDP is organized and implemented through cooperative agreements with health departments in the 50 states, the District of Columbia, 4 U.S. territories, and 13 American Indian/Alaska Native tribal organizations. The NBCCEDP provides support and assistance for screening medically underserved, low-income women ages 18 years to 64 years for cervical cancer and ages 40 years to 64 years for breast cancer. The NBCCEDP also provides diagnostic testing and follow-up services for women whose screening tests are abnormal. From its inception through 2004, the NBCCEDP has provided 6.5 million screening examinations to 2.7 million women and has diagnosed 26,000 breast cancers and 1700 cervical cancers.3
The NBCCEDP, as the largest organized cancer screening program in the U.S., seeks to maximize the benefits of breast and cervical cancer early detection for the nation's uninsured, low-income women not only by seeking to reach and screen hard-to-reach eligible women. The NBCCEDP uses a comprehensive approach to ensure that all women benefit from the program through educational activities, coalitions/partnerships, and quality assurance and improvement in cancer screening and diagnostic services. Furthermore, the program strives to reach and screen as many eligible women as possible. However, given the current climate of increasing healthcare costs and limited resources, there is a continuing emphasis on economic costs of delivering screening and diagnostic services to eligible women.
In 2003, we undertook a multiyear research project to systematically address economic issues related to the NBCCEDP. In this report, we present the results of a cost analysis of 9 selected programs. We addressed 3 economic-related questions: 1) What is the cost per woman screened and the cost per woman served? 2) What is the cost per woman served by program component? and 3) What is the cost per cancer detected through the program? Cost per woman screened is the cost of screening a woman who received NBCCEDP-funded screening procedures, which includes either mammography and a clinical breast examination (CBE) or the Pap test. Cost per woman served is the cost of screening a woman in the program plus the cost of diagnostic follow-up of abnormal results for a woman who was screened outside the program but who was referred to the program at the diagnostic stage.
Given these research questions, we estimated 1) the cost per woman served with and without in-kind (nonfederal) contributions; 2) the cost per woman served per each program component; 3) the cost per woman served for clinical services; 4) the cost per woman screened for breast and cervical cancer, respectively; and 5) the cost per breast and cervical cancer detected. Cost data on screening and diagnostic services will be essential in assisting policy and decision makers in allocating program resources equitably across the individual programs.
MATERIALS AND METHODS
Program Selection and Data Collection Procedures
To address the questions stated above, we used both qualitative and quantitative data4 to select 9 programs. The details of data collection methods that were used for this cost analysis have been described previously (unpublished results). Briefly, we visited 4 programs. These programs were selected by their structure for delivering screening services (eg, centralized, decentralized, or mixed), by the volume of women screened, and by location. We used the same questionnaire for all 4 sites. We conducted a group interview with key staff members, including the program director and financial manager.
Using qualitative information obtained from the site visits, we developed a questionnaire to systematically collect activity-based costs. The questionnaire was developed based on well established methods of collecting cost data for program evaluation.5–8 Cost data were collected on personnel, consultants, contracts, materials, supplies, administration/overhead (eg, telephone, rent, website), and other consumables. We collected cost data on the following activities or program components: program management, screening and diagnostic procedures, case management, tracking and follow-up, data management, public education and outreach, professional education, coalitions/partnerships, quality assurance and improvement, and surveillance and evaluation.
The questionnaire was administered to 9 programs, which were identified by a combination of random selection and purposive sampling.9 The program selection process is outlined in Figure 1. We began with 51 programs that represented the 50 states and the District of Columbia; then, we excluded the 4 programs we had visited. The remaining programs (n = 47 programs) were stratified into 3 categories: centralized programs, decentralized programs, or mixed programs.
Centralized programs offer clinical services in satellite offices, but all other program activities are performed centrally, such as tracking and case-management services. Decentralized programs contract with local and regional health departments, private hospitals, or other healthcare facilities to fully manage and provide screening and diagnostic services and other program activities. Programs with a mixed service delivery structure have both centralized and decentralized features.
We randomly selected 6 programs within these 3 strata (n = 18 programs). From each of the 6 programs, we used purposive sampling to select 3 programs in each stratum (n = 9 programs). To ensure diversity across all of the programs, we used the following criteria to select 9 programs for data collection: lessons learned from the site visits, number of women served, number of women screened, distribution of screening (ie, the proportion of breast and cervical cancer screenings), type of funding source, financial data from the program, geographic location, and size of the area served. Data were collected on these 9 programs from July 2003 through June 2004.
To ensure the quality of our data, first, we conducted a thorough pilot study; then, we conducted several rounds of follow-up telephone calls with the 9 programs to ensure that the data we received were accurate and complete. Overall, we observed that the information reported by the programs was accurate; when there were inconsistencies, we consulted with the program.
Measures of Effectiveness
The effectiveness measures were obtained from the NBCCEDP surveillance database. Details of this database have been described elsewhere.10, 11 To measure effectiveness, we used 3 variables: 1) the number of women screened for breast or cervical cancer, 2) the number of women served, and 3) the number of cancers detected. The number of women screened equaled those who received NBCCEDP-funded screening procedures, which included either mammography and a CBE or the Pap test. The number of women served included those screened in the program plus those screened outside the program who were referred to the program for diagnostic follow-up of abnormal screening results. The number of breast cancers detected included both carcinoma in situ (CIS) and invasive cancer. The number of cervical cancers included both cervical intraepithelial neoplasia (CIN2/CIN3/CIS) and invasive cancer.
Data Analysis and Calculation of Intermediate Outcome Measures
In this study, we estimated only intermediate outcome measures, which reflect relatively near-term effects of the program on the population being screened or served.8, 12 These intermediate measures included the cost per woman screened or served and the cost per cancer detected. One of the advantages of this approach is that it helps to guide resource allocation among the programs. The data collected were entered into a series of Microsoft Excel (Microsoft Corporation, Redmond, Wash) spreadsheets and were analyzed using that platform. The analysis was conducted from a program perspective, suggesting that we included only the direct costs of providing preventive cancer screening services. Because the study was conducted during a 1-year period, costs and outcomes were not discounted.
We calculated several intermediate outcome measures from the 9 programs. First, we calculated the cost per woman screened for breast cancer (or cervical cancer) by using the reported cost of screening plus the cost of office visits divided by the number of women screened. Second, we calculated average costs per woman served with and without in-kind contributions by using the average total program cost with and without these contributions divided by the average total number of women served. We defined in-kind contributions as those contributions that strictly represented the value of resources donated to each program through other sources (ie, opportunity cost). Third, to ascertain the level of compliance with legislative requirements that ≥60% of NBCCEDP funds must be used for direct clinical services,13 we calculated the cost of clinical services per woman served by dividing the reported average total cost of clinical services by the number of women served. We defined the cost of clinical services to include the cost of screening and diagnostic follow-up, referral for treatment and the cost of case management.13 Fourth, we calculated costs by program component per woman served; we also calculated the percent distribution of the total program cost represented by each component. Fifth, we calculated the average cost per breast cancer detected and, separately, calculated these costs by CIS and invasive cancer only. Finally, we calculated average cost per cervical cancer detected and, separately, the average cost per CIN2/CIN3/CIS only and per case of invasive cervical cancer.
Because the selected programs are heterogeneous, the estimated costs may not be representative of the costs incurred by programs around the U.S. in delivering screening and diagnostic follow-up services to a woman. To assess how the heterogeneity of these programs affected the results of the cost analysis, we performed sensitivity analyses using the Monte Carlo simulation method.14–16 We constructed probability distributions for each of the intermediate outcome measures discussed above. For example, we fitted normal distributions to the cost per woman served with and without in-kind contributions, triangular distributions to the cost per woman screened for breast and cervical cancer, and log-normal distributions to the respective cost per breast and cervical cancer detected. Using the fitted probability distributions, we performed simulations using @Risk software (version 4.5; Palisade Corporation, Newfield, NY), an Excel add-in that employs Monte Carlo sampling methods. In total, 3500 simulation runs were performed. On each simulation run, a value for each intermediate outcome measure (eg, cost per woman screened for breast cancer) was drawn from its associated distribution, and this value was stored as an output. Using the output of the 3500 simulation runs as data, descriptive statistics were calculated, including the mean, standard deviation, median, and percentile intervals for all outcome measures. We report the results of the simulation as medians with 25th and 75th percentile intervals.
The median number of women served was 6287 (25th–75th percentile, 2926–10,515 women), and the median total program cost without in-kind contributions was $3.3 million (25th–75th percentile, $1.4–4.5 million) across the 9 programs (Table 1). With in-kind contributions, the median total program cost was $4.9 million (25th–75th percentile, $1.9–5.3 million) or 33% higher than the cost without these contributions. The median cost per woman served without in-kind contributions was $519.16 (25th–75th percentile, $352.16–532.34); and, with in-kind contributions, it was $554.57 (25th–75th percentile, $503.05–661.11). The median cost of clinical services per woman served was $247.59 (25th–75th percentile, $208.42–289.78). The median number of women screened per program was 5880 (25th–75th percentile, 2818–9877 women) for breast cancer and 3724 (25th–75th percentile, 2278–7159 women) for cervical cancer (Table 2). The cost per woman screened was $94.43 (25th–75th percentile, $72.90–120.31) for breast cancer and $55.64 (25th–75th percentile, $43.60–62.01) for cervical cancer.
|Program||Total No. of Women Served||Without In-kind Contributions, $*||With In-kind Contributions, $†|
|Total Program Cost||Total Cost for Clinical Services||Cost per Woman Served||Cost per Woman Served for Clinical Services‡||Total Cost From In-kind Contributions||In-kind Contributions per Woman Served||Cost per Woman Served||Total Program Cost|
|Variable||Breast Screening||Cervical Screening|
|Mean ± SD||Median (25th–75th Percentile)||Mean ± SD||Median (25th–75th Percentile)|
|No. of women screened||7233 ± 5448||5880 (2818–9877)||4745 ± 3282||3724 (2278–7159)|
|No. of follow-up visits for abnormal results||1363 ± 1132||1240 (302–2125)||416 ± 549||178 (91–418)|
|Cost per office visit, $*||35.47 ± 11.85||39.91 (26.53–41.44)||35.47 ± 11.85||39.91 (26.53–41.44)|
|Total costs of office visits, $||265,857 ± 231,957||243,692 (60,884–394,765)||172,513 ± 140,088||154,339 (44,161–264,269)|
|Total cost of screening, $||445,434 ± 324,034||487,588 (158,972–689,426)||74,129 ± 35,150||79,322 (64,766–84,804)|
|Total cost of screening and office visit, $||711,291 ± 543,403||859,034 (216,022–933,118)||246,642 ± 169,572||230,931 (99,330–347,897)|
|Cost per woman screened, $||105.09 ± 47.65||94.43 (72.90–120.31)||59.75 ± 30.05||55.64 (43.60–62.01)|
The median number of breast cancers detected (CIS plus invasive carcinoma) was 75 (25th–75th percentile, 27–123 breast cancers); for cervical cancer (including CIN2/CIN3/CIS and invasive carcinoma), this number was 26 (25th–75th percentile, 12–51 cervical cancers) (Table 3). The median costs per cancer detected were $10,566 (25th–75th percentile, $8417–12,714) for breast cancer and $13,340 (25th–75th percentile, $1596–25,084) for cervical cancer.
|Variable||Median (25th–75th percentile)|
|Breast screening||Cervical screening|
|Average no. of cancers detected|
|All||75 (27–123)||26 (12–51)|
|CIS only||14 (7–21)||—|
|CIN2/CIN3/CIS only||—||23 (10–47)|
|Invasive cancer only||61 (16–105)||2 (1–4)|
|Average cost per cancer detected ($)|
|All||10,566 (8417–12,714)||13,340 (1596–25,084)|
|CIS only||46,201 (31,283–66,876)||—|
|CIN2/CIN3/CIS only||—||14,304 (1937–26,675)|
|Invasive cancer only||14,259 (10,662–18,958)||63,768 (35,081–92,447)|
The results of the multivariate sensitivity analyses are summarized in Figures 2 and 3. The median costs per woman served by the NBCCEDP component are shown in Figure 2. Screening accounted for the highest cost ($220.65; 25th–75th percentile, $172.53–268.75) (Fig. 2), which represented 48.2% of the cost per woman served. Public education/outreach was the second highest with an estimated cost of $62.52 (25th–75th percentile, $23.34–101.02). Coalitions/partnerships had the lowest cost of $1.76 (25th–75th percentile, $0.44–3.07). The estimated median costs per woman served or screened, which are shown in Figure 3, varied slightly from the baseline values reported in Tables 1 and 2. Compared with the baseline, this variation ranged from a 0.3% decrease for the cost per woman served for clinical services to a 9.9% decrease for the cost per woman served without in-kind contributions. Conversely, the estimated median cost per woman served with in-kind contributions was 9.5% higher in the sensitivity analysis in contrast to the estimated value reported at baseline. The estimated costs per woman screened for breast and cervical cancers were 6.9% higher (cervical cancer) and 10.1% higher (breast cancer) in the sensitivity analysis compared with the value reported at baseline. These variations in the estimated cost per woman served (with and without in-kind contributions), screened, and clinical services reflect the heterogeneity that exists among these programs.
Using 9 programs in the NBCCEDP, we calculated a median cost per woman served of $555 when the value of in-kind contributions was included; without in-kind contributions, the median cost per woman served was $519. The cost of providing direct clinical services per woman served was $248. The cost of screening a woman for breast cancer using mammography was $94, and the cost per cancer detected was $10,566. For cervical cancer, these costs were $56 and $13,340, respectively. In an era of limited resources, these cost estimates can provide useful information for program planning and budget allocation. Lack of cost information is often a limiting factor in reaching and screening women who are eligible for the NBCCEDP.
It often is difficult to compare cost studies, because they use different types of costing methods, depending on the objective and the viewpoint of the study.8–12 The current study was conducted from the program's viewpoint, which implies that only direct costs incurred by the programs in providing cancer screening services were included in the study. We reviewed the literature to extract data from studies that also used the same viewpoint to generate average costs for breast and cervical cancer screening. Overall, we observed that our estimated average costs for breast and cervical cancer screening did not differ substantially from other estimates reported in the literature. For example, breast screening studies have reported that average costs of screening ranged from $64 to $172 (in 2004 dollars).17–22 For cervical screening, reported estimates (in 2004 dollars) ranged from $32 to $114.18, 23–28
Few studies have been reported on the cost per cancer detected for public health programs.29–31 These studies estimated that the cost per breast cancer detected ranged from $12,558 to $18,238 when adjusted to 2004 dollars. In general, these estimates are comparable to the cost estimates reported in the current article, because those studies were conducted in different settings, timeframes, and populations. For example, the studies by Hurley et al. and Gerard et al. were conducted in Australian mammography programs30, 31 with a different healthcare delivery system and perhaps different eligibility criteria to qualify for their programs. For cervical cancer, we could not find a comparable cost per cancer detected for a similar public health program. This reveals that, although substantial literature has been published on the cost-effectiveness of breast and cervical cancer, very few studies have been conducted in public health programs for targeted populations. Another reason could be that these studies are not reporting the cost of cancer as an outcome measure.
Because the NBCCEDP was established by the U.S. Congress to provide free or low-cost, comprehensive breast and cervical cancer screening and diagnostic follow-up of abnormal results to medically underserved, low-income women, the NBCCEDP is grounded in public law with regulations that must be complied with by participating states, district, territories, and tribal organizations. One such legislative regulation states that no less than 60% of program funds must be used for direct clinical services. These clinical services include screening and diagnostic follow-up, referral for treatment, and case management.13 In the current study, we observed that 58.2% of the program resources (excluding in-kind contributions) are allocated to clinical services, which is very close to the legislative requirement.
The remaining 40% of the program's resources are used to support other activities that are essential to the success of clinical services. These activities include data management, public education and outreach, professional education, coalitions/partnerships, quality assurance and improvement, and surveillance and evaluation. The support of these activities by policy makers is intended to address factors other than direct financial barriers that may have an impact on the ability of uninsured low-income women to receive cancer screening services. Behavioral intervention studies have identified these factors include both patient and provider behavior.32–38 For instance, studies have identified that the degree to which individual patients seek cancer screening services is influenced by usual source of care, public information and education, outreach, physician recommendation, and implementation of interventions to increase general knowledge of prevention among health providers.39–45 The NBCCEDP allocates a proportion of its resources to public education and outreach campaigns to increase program awareness among eligible women and to encourage them to use program services. In the current study, we observed that selected programs spent 12.1% of their total cost (or $62.52 per woman served) on this activity and that they spent another 5.7% (or $26.47 per woman served) on professional education. Quantifying the amount of the program resources allocated to different program activities is vital to the success of the NBCCEDP, and it provides accountability on how resources are used to influence screening behavior.
There are some caveats in our analysis. First, although we used a combination of random selection and purposive sampling9 to select 9 programs, the average (or median) costs reported here may not be generalizable beyond the 9 programs we selected for this study. This is because of substantial variations that exist among the programs nationally. However, we performed a detailed literature search and conducted appropriate sensitivity analyses to assess the consistency of our findings. We plan to conduct more detailed, empiric investigation to explore the sources of variation between average cost per woman served or cost per cancer detected on the number of women served or the number of cancers detected. Describing the true underlying factors may help public health officials understand why a given program may not be able to allocate its limited resources more efficiently to screen as many eligible women as possible. Second, we analyzed only 1 year of data. We know that program funding and other sources of resources vary from year to year, depending on the activities planned in that year. This year-to-year variation may have affected our calculated costs of delivering screening services. An ideal study would be to analyze economic cost data from multiple years, which is part of Phase 2 of this project, which currently is being conducted. A third concern is that selected programs (within the 9 we analyzed) could not separate the cost of office visits for breast screening from those for cervical screening; thus, we assumed that these costs are identical. This assumption may have caused us to underestimate or overestimate the costs of screening for these cancers; however, our review of the literature indicated that the impact of this limitation on average costs may be minimal. For instance, Goldie et al. reported the cost of an office visit for cervical screening ranged from $11 to $50,28 a range that includes our estimate of $35.47. Fourth, many of the programs could not distinguish the cost of CBE from that of mammography. The programs, however, informed us that the cost of CBE is very small and, in most women, is included in the costs for office visits. Two studies have reported that the cost of CBE ranges from $8.16 to $24.74 (adjusted to 2004 dollars).17, 18 Because we were unable to separate the cost of CBE from mammography, the average cost of breast screening we report may be a combination of mammography and CBE. Finally, we reported the cost per cancer detected as an intermediate outcome measure, but a program such as the NBCCEDP, which is designed to detect early-stage cancer, would save more life-years than programs that detect cancers at later stages. Therefore, reporting intermediate outcomes for this program may provide practical information on the direct cost of detecting a case of cancer in medically underserved, low-income women. However, it may not provide complete information on the benefits of the NBCCEDP. Hence, readers should note that this study is not a cost-effectiveness analysis, but a cost analysis.
These caveats notwithstanding, we believe that the results presented in this report provide a good picture of the overall allocation of NBCCEDP resources in the selected programs. We also believe that our findings may help to inform decision making in the NBCCEDP once all programs have been surveyed. To our knowledge, our study provides the first systematic cost analysis in the selected programs and is unique, in that it attempts to determine the real costs of providing comprehensive screening and diagnostic follow-up services to low-income, uninsured women.
This study addressed short-term economic costs in 9 programs. Currently, the CDC is conducting Phase 2 of this project in all 68 programs operating in the U.S. Phase 2 addresses long-term economic issues related to the evaluation of the NBCCEDP. These issues include developing cost-assessment tools for the better collection of data on economic cost and developing cost-effectiveness models to estimate the full costs and benefits of the NBCCEDP. Phase 2 also includes developing econometric methods that would relate outcomes and inputs in allocating program resources based on the effectiveness and efficiency of each program; conducting threshold and scenario analyses to determine the amount of resources required to screen 25%, 50%, or 75% of the eligible women nationally; estimating the cost of treating a woman diagnosed with cancer in the NBCCEDP; describing the methods used by programs to deliver screening and diagnostic follow-up services; documenting the extent to which these programs use a common set of service delivery structures; and determining how different types of service delivery structures affect the number of women screened or served. It is our hope that addressing these economic issues will provide invaluable information that program directors and managers can use to make informed decisions on how to allocate NBCCEDP resources more efficiently. It also will provide a framework for establishing the minimum number of NBCCEDP-eligible women who can be screened given the resources available.
We sincerely thank the selected programs that participated in this phase of the project. In addition, we thank Mary C. White, Donald K. Blackman, and Susan True for their support of this project. We also thank the National Breast and Cervical Cancer Early Detection Program editorial office for their review of an earlier draft of this article and Amber Moore and Caren Kramer for their assistance in developing the site-visit instrument.
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- 13Centers for Disease Control and Prevention, National Breast and Cervical Cancer Early Detection Program. Policies and Procedures Manual. Atlanta, Ga: Centers for Disease Control and Prevention; 2005.
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