Mammography Services: Impact of Federal Legislation on Quality, Access, and Health Outcomes

Published by the Government Accountability Office on 1997-10-21.

Below is a raw (and likely hideous) rendition of the original report. (PDF)

                 United States General Accounting Office

GAO              Report to Congressional Committees

October 1997
                 Impact of Federal
                 Legislation on Quality,
                 Access, and Health

      United States
GAO   General Accounting Office
      Washington, D.C. 20548

      Health, Education, and
      Human Services Division


      October 21, 1997

      The Honorable James M. Jeffords
      The Honorable Edward M. Kennedy
      Ranking Minority Member
      Committee on Labor and Human Resources
      United States Senate

      The Honorable Thomas J. Bliley, Jr.
      The Honorable John D. Dingell
      Ranking Minority Member
      Committee on Commerce
      House of Representatives

      Breast cancer is the most commonly diagnosed nonskin cancer and the
      second leading cause of cancer deaths among American women. Experts
      estimate that during the 1990s as many as 1.8 million women will be
      diagnosed with breast cancer, and 500,000 will die from it. The probability
      of survival increases significantly, however, when the disease is
      discovered in its early stages. Currently, the most effective technique for
      early detection of breast cancer is screening mammography, an X-ray
      procedure that can detect small tumors and breast abnormalities up to 2
      years before they can be detected by touch. The use of mammography as a
      tool for detecting early cancer continues to increase. The proportion of
      women aged 50 and older who had received mammograms in the past year
      increased from 26 percent in 1987 to 57 percent in 1995, according to the
      Centers for Disease Control and Prevention (CDC).1

      The effectiveness of mammography as a cancer detection technique is
      directly related to the quality of mammography procedures. To address
      concerns about variations in the quality of mammography services
      provided by about 10,000 facilities throughout the United States and its
      territories, the Congress passed the Mammography Quality Standards Act
      of 1992 (MQSA). This act established a number of requirements aimed at
      strengthening mammography quality, including requiring accreditation and
      annual inspection of mammography facilities. The act is currently under
      congressional consideration for reauthorization.

       The proportion of women 40 to 49 who had received mammograms in the past 2 years also increased:
      from 59 percent in 1990 to 66 percent in 1995.

      Page 1                                                GAO/HEHS-98-11 Mammography Services

                   The act also mandated that we assess and report on the program
                   established by the Food and Drug Administration (FDA) to implement these
                   requirements. We issued two interim reports, the first focusing on the act’s
                   initial impact on access to and quality of mammography services, and the
                   second focusing on FDA’s annual inspection program.2 As required by the
                   act, this final report focuses on assessing the act’s effect on (1) the quality
                   of mammography services, (2) early detection of breast cancer to save
                   lives, and (3) women’s access to mammography services. We also followed
                   up on the status of our previous recommendations to FDA (see app. II).

                   This report is based primarily on our analysis of data obtained from FDA’s
                   certification and annual inspection programs, as well as on research we
                   reviewed regarding mammography’s effectiveness in cancer detection. We
                   also consulted with many mammography and cancer experts during the
                   course of our review. Details of our scope and methodology are presented
                   in appendix I. Our work was done between January and August 1997 in
                   accordance with generally accepted government auditing standards.

                   MQSA has increased mammography facilities’ adherence to accepted quality
Results in Brief   assurance standards, which has, in turn, had a positive effect on
                   mammography services. MQSA established nationwide minimum standards
                   and required facility accreditation, which resulted in thousands of
                   facilities’ having to improve their quality assurance processes. FDA’s annual
                   inspections of facilities, now in their third year, continue to show
                   increasing compliance with these national quality standards. Further
                   evidence of quality improvement can be seen in the quality of the X-ray
                   images. Before the act took effect, 11 percent of facilities tested were
                   unable to pass image quality tests; now, the nationwide figure is 2 percent.

                   Experts agree that improving the quality of mammography images should
                   lead to more accurate interpretation by physicians and, therefore, to
                   improved early detection of breast cancer. However, neither data nor
                   research methodologies are now in place to clearly establish these links.
                   FDA has established federal qualification requirements for physicians who
                   interpret mammograms but has not established criteria for measuring
                   interpretation accuracy. Furthermore, comparable pre- and post-MQSA
                   clinical data for measuring mammography performance and cancer
                   outcome either do not exist or, for a number of reasons, are too limited to
                   be useful. Some steps are being taken to address interpretation accuracy

                    Mammography Services: Initial Impact of New Federal Law Has Been Positive (GAO/HEHS-96-17, Oct.
                   27, 1995) and FDA’s Mammography Inspections: While Some Problems Need Attention, Facility
                   Compliance Is Growing (GAO/HEHS-97-25, Jan. 27, 1997).

                   Page 2                                               GAO/HEHS-98-11 Mammography Services

             and outcome measurement issues. FDA’s proposed final regulations require
             each facility to use its own data to monitor physicians’ performance on
             interpretation. In addition, as provided by MQSA, the National Cancer
             Institute (NCI) has established a Breast Cancer Surveillance Consortium of
             nine research projects. These projects are making progress in both
             developing a methodology and collecting clinical data for assessing trends
             in mammography performance in detecting breast cancer and reducing

             When MQSA was enacted, concern was expressed that some women might
             have difficulty obtaining mammography services if facilities chose to close
             down rather than to upgrade their operations to meet the new quality
             standards. We found no indication that access problems had developed as
             a result of MQSA. Nationwide, the number of facilities that stopped offering
             mammograms was nearly offset by the number of new entrants into the
             field. Further, 92 percent of all facilities that closed were within 5 miles of
             a facility that remained open, and our discussions with officials in states
             with the highest closure rates did not reveal any evidence that access
             problems had occurred.

             FDA has informed us that it has acted to implement our earlier
             recommendations for strengthening the MQSA inspection program. For
             example, FDA has efforts under way to establish procedures, guidance, and
             training to ensure timely compliance with MQSA standards. Our previous
             recommendations and the status of FDA actions taken on them appear in
             appendix II.

             Research studies, including randomized clinical trials, indicate that
Background   widespread use of mammography could reduce breast cancer mortality by
             one-third, especially in older women. The value of mammography in
             reducing mortality is directly tied to its ability to detect cancer at its
             earliest stages. Mammography is capable of detecting tumors much
             smaller than those detected by other means (see fig. 1).3

              Mammography, however, is not a perfect tool; even under ideal conditions, 10 to 20 percent of breast
             cancers cannot be detected by mammography.

             Page 3                                                   GAO/HEHS-98-11 Mammography Services

Figure 1: Size of Breast Tumors Found by Mammography and Self-Examination

                                        Source: Altered graphic from Choices, Marion Morra and Eve Potts (New York City: Avon Books,
                                        1994), p. 303.

                                        Although mammography can be very useful in finding early-stage cancer, it
                                        is one of the most technically challenging radiological procedures, and
                                        ensuring the quality of the image is difficult. If the image is poor, tumors
                                        and abnormalities may go undetected. To illustrate, two images of the
                                        same patient who had a cancerous tumor are presented in figure 2. The
                                        tumor is visible in the picture on the right, where the image is of higher
                                        quality, but it is blurred and indecipherable in the picture on the left.

                                        Page 4                                               GAO/HEHS-98-11 Mammography Services

Figure 2: Low- and High-Quality Mammography Images of the Same Patient

                                        Source: FDA.

                                        Accurate interpretation of mammograms is equally as important as image
                                        quality. According to radiological experts, mammograms are the most
                                        difficult radiographic images to read, and misreading mammograms can
                                        have considerable consequences. A mammogram that is incorrectly
                                        interpreted as showing an abnormality could cause a woman to go through

                                        Page 5                                 GAO/HEHS-98-11 Mammography Services

                             unnecessary and costly follow-up procedures, such as ultrasound or
                             biopsies. A mammogram that is read as normal when an abnormality is
                             actually present could result in missed diagnosis of early lesions and
                             delayed treatment, which could cost a woman’s life.

                             MQSA established minimum national quality standards for mammography
                             facilities and contained a number of provisions designed to ensure the
                             quality of the image and its interpretation. Among other things, MQSA
                             required that

                         •   FDA  establish quality standards for mammography equipment, personnel,
                             and practices;
                         •   all mammography facilities be accredited by an FDA-approved accrediting
                             body once every 3 years and obtain a certificate from FDA in order to
                             legally provide mammography services after October 1, 1994; and
                         •   all mammography facilities have an annual evaluation by a qualified
                             medical physicist and an annual inspection by FDA-approved inspectors
                             that includes a test of image quality.

                             FDA implemented MQSA under interim regulations issued in December 1993.
                             The quality standards of FDA’s interim regulations were substantially based
                             on standards and an accreditation program developed in 1987 by the
                             American College of Radiology (ACR), a private, nonprofit professional
                             association of radiologists. Since early 1994, FDA has been working with
                             the National Mammography Quality Assurance Advisory Committee to
                             develop final regulations.4 On April 3, 1996, FDA published the proposed
                             final regulations for public comment but as of September 1997 had not
                             issued the final regulations.

                             To assess MQSA’s effect on the quality of mammography services, we
MQSA Has Had a               analyzed the results of implementing three important quality assurance
Positive Effect on the       requirements of the act: accreditation review, annual facility inspections,
Quality of                   and testing the quality of X-ray images. Both accreditation and annual
                             inspection processes required by MQSA show that facilities are doing a
Mammography                  better job of complying with quality standards, and image tests show that
Services                     the quality of images has improved.

                              The committee is responsible for advising FDA on the appropriateness of quality standards for
                             mammography facilities and accrediting bodies and for studying (1) the effect of MQSA on access to
                             services in rural and health-professional-shortage areas, (2) the costs and benefits of compliance with
                             MQSA, and (3) the sufficient number of medical physicists after Oct. 1, 1999, to ensure compliance
                             with MQSA. As of September 1997, the committee had not submitted final reports to the Congress.

                             Page 6                                                    GAO/HEHS-98-11 Mammography Services

Accreditation Process Has   MQSA required that all of the nation’s approximately 10,000 mammography
Brought Improvement in      facilities, regardless of location or setting, pass an accreditation review to
Compliance With Quality     ensure that they meet quality assurance requirements for equipment
                            performance, radiation safety, personnel qualifications, and clinical image
Standards                   quality, among other things. Before MQSA, between 37 and 44 percent of
                            mammography units in the country met ACR’s quality assurance
                            requirements by participating in ACR’s voluntary accreditation program.
                            Since MQSA’s implementation, FDA has approved ACR and the states of
                            Arkansas, California, and Iowa as official accrediting bodies. Because of
                            ACR’s pre-MQSA involvement in establishing the voluntary accreditation
                            program, it serves as the major accreditation body, responsible for more
                            than 95 percent of the workload.

                            MQSA’s quality standards and the related accreditation process have had a
                            substantial effect on improving quality assurance activities. In an earlier
                            report,5 we noted that when MQSA initially took effect, many
                            mammography units did not meet the standards. For example, between
                            October 1, 1994, and August 1, 1995, about 2,600 (35 percent) of the
                            mammography units that sought ACR accreditation initially failed to meet
                            accreditation requirements. While almost all of these units were eventually
                            granted full accreditation, they first had to demonstrate that they had
                            improved their quality assurance activities.

                            ACR data suggest that the accreditation process continues to result in more
                            facilities’ meeting quality assurance standards. For example, the
                            percentage of facilities that passed ACR’s accreditation on the first attempt
                            increased from 66 percent in 1995 to 82 percent in 1997.6

On-Site Inspections Show    MQSA’s inspection requirement gives FDA another means to ensure that
Continued Improvement in    facilities comply with standards on a day-to-day operating level. While
Compliance                  accreditation is generally a mail-in-process that involves the submission
                            and review of application materials, annual inspections are conducted on

                             GAO/HEHS-96-17, Oct. 27, 1995.
                             The accreditation process under ACR allows facilities to go through two reviews. Facilities that fail
                            the first accreditation review can correct deficiencies and resubmit their application materials for a
                            second review. If a facility fails the second review, accreditation is denied. The Arkansas and Iowa
                            accreditation bodies allow facilities to have more than two reviews before denying accreditation.
                            While the state of California has been approved as an accreditation body, it contracts with ACR for a
                            portion of accreditation review.

                            Page 7                                                    GAO/HEHS-98-11 Mammography Services

site, which allows inspectors to verify information provided during the
accreditation process.7

As FDA entered its third year of annual inspections, inspection results
continued to show improvement in facility compliance with MQSA quality
standards. Both level 1 and level 2 violations, which FDA considers to be
significant and for which it requires the facility to submit written plans for
corrective actions, have dropped.8 As shown in figure 3, from fiscal year
1995 to fiscal year 1997, the proportion of inspected facilities whose
highest-level violation was level 1 dropped from 3 percent to 1 percent,
and the proportion whose highest-level violation was level 2 dropped from
20 percent to 12 percent.9 Most facilities with violations had only level 3
violations (considered by FDA to be minor deviations); these numbers also
dropped during the 3-year period. The portion of facilities with no
violations at all nearly doubled, from about 30 percent in 1995 to about
55 percent in 1997.

Annual inspections are generally performed by FDA-approved state inspectors. FDA has contracted
with virtually all states and territories to conduct inspections.
 Level 1 violations are those that can have the most detrimental effect on the quality of mammography
services—for example, a facility’s having personnel who do not meet FDA’s minimum qualification
standards. For level 1 violations, FDA issues a warning letter; the facility must respond in writing to
FDA within 15 working days of receiving the warning letter. Level 2 violations are considered less
significant—for example, a facility’s not having an evaluation of equipment by a medical physicist
during the past 14 months—and do not generate a warning letter. However, the facility must respond
in writing to FDA within 30 working days of receiving its inspection report. Level 3 violations—for
example, a facility’s not having the required documentation of a quality control test—do not require a
written response.
 Under their contracts with FDA, many states began inspecting facilities in January 1995, but some did
not begin until later. In fiscal year 1997, FDA began to manage its inspection workload and compare its
inspection results by fiscal years. Results for 1997 are for facilities inspected during the first 9 months
of the fiscal year. We have no reason to assume that the percentages will change greatly for facilities
that will be inspected during the remainder of the year.

Page 8                                                     GAO/HEHS-98-11 Mammography Services

Figure 3: Comparison of
Mammography Facilities’ Inspection
Results, Fiscal Years 1995-97

                                     Another way to assess whether facilities are improving their compliance is
                                     to consider the extent of repeat violations—violations found in one
                                     inspection and recurring in the next inspection. As of June 30, 1997, 8,619
                                     facilities had been inspected at least twice. Facilities had a better record
                                     for not repeating the more severe violations than they did for the minor
                                     deviations. Less than 1 percent of facilities that had level 1 violations in the
                                     first year repeated one or more of the same violations in the second year,
                                     while about 17 percent of those with level 3 violations in the first year
                                     repeated one or more of the same violations in the second year. FDA
                                     considers level 3 violations to be minor findings. However, to reduce the
                                     incidence of repeat violations, and in response to a recommendation in
                                     our second report, FDA has revised its policy guidance to include
                                     procedures for addressing repeat level 3 violations.

                                     Page 9                                      GAO/HEHS-98-11 Mammography Services

More Facilities Are Passing   One of the most important aspects of FDA’s annual inspection process is
Tests of Image Quality        testing the performance of a facility’s mammography system through what
                              is called a “phantom image test.” This test involves taking an X-ray image
                              of a plastic block containing 16 test objects to determine how many of the
                              test objects can be seen on the image generated by the facility’s
                              mammography equipment.10 To pass the evaluation, the phantom image
                              must show at least the minimum number of test objects required by FDA.11

                              Because FDA was already conducting some phantom image testing before
                              MQSA, it is possible to make general comparisons about image quality
                              before and after the law took effect. Before MQSA, FDA, in a cooperative
                              agreement with the Conference of Radiation Control Program Directors (a
                              professional association of state and local radiation control program
                              officials), conducted several Nationwide Evaluation of X-ray Trends (NEXT)
                              surveys to evaluate the technical performance of mammography facilities.
                              The phantom image scores from these pre-MQSA NEXT surveys are
                              considered the baseline for comparison with the phantom image scores
                              from post-MQSA annual inspections, because the standards for evaluating
                              phantom images are essentially identical.

                              NEXT survey data before MQSA implementation showed that phantom image
                              scores were improving under ACR’s voluntary accreditation program. Data
                              from the post-MQSA inspections show continued improvement in image
                              quality, as indicated by the acceptable rates of phantom image scores. For
                              example, the proportion of facilities with acceptable phantom image
                              scores has remained at 98 percent since 1995, as compared with
                              89 percent in 1992.

                               The plastic block, which represents an average-sized compressed breast, contains a wax insert that
                              holds 16 test objects—6 fibrous structures (fibers), 5 embedded microcalcifications (speck groups),
                              and 5 different-sized tumor-like masses that simulate growths that could be cancerous.
                                To pass the phantom image test, at least 4 fibers, 3 speck groups, and 3 masses need to be visible in
                              the phantom image.

                              Page 10                                                   GAO/HEHS-98-11 Mammography Services

                            Because MQSA can be linked to improved quality of mammography images,
Data and                    a logical case can be made that MQSA has also helped improve
Methodology                 mammography interpretation, thereby improving early breast cancer
Problems Prevent            detection and, ultimately, saving lives. However, neither data nor research
                            methodologies are now in place to clearly demonstrate these links. One
Measuring MQSA’s            problem is that criteria have not been established to assess how reliably
Impact on Saving            images are being interpreted. Another is the lack of comparable clinical
                            data12 for measuring any outcome changes that have occurred as a result
Lives                       of the act. In addition, researchers still disagree on how to compute
                            mammography performance and cancer outcome measures. In response to
                            MQSA requirements, NCI has funded research and established a consortium
                            that is making progress in collecting clinical data and resolving
                            disagreements over how to measure mammography performance and
                            cancer outcomes.

MQSA’s Impact on the        We were unable to determine if MQSA has had an effect on improving the
Quality of Image            accuracy and reliability with which mammograms are interpreted, because
Interpretation Is Unknown   criteria are not available to determine an appropriate measure. How to
                            develop a quality assurance system for monitoring the accuracy with
                            which mammograms are interpreted is a controversial issue in the medical
                            community. Several academic studies have shown wide variation in the
                            interpretation of the same mammogram by different radiologists. On one
                            hand, some experts suggest that some type of peer review or proficiency
                            test is needed to improve accuracy. On the other hand, FDA and others take
                            the position that such measures are too difficult and costly to implement
                            and that a self-monitoring, facility-based system of physician performance
                            assessment is a better approach to achieve the goal of quality

                            FDA’s  current approach reflects its preference for a facility-based
                            monitoring system that tracks and reviews mammography and pathology
                            results. Current MQSA regulations include a general requirement that each
                            facility have a medical audit system in place to collect and review clinical
                            data, which includes follow-up on positive mammograms (those identified
                            as suspicious or highly suggestive of cancer) and their correlation to
                            biopsy results. In proposed final regulations published in April 1996, FDA
                            requires that at least one interpreting physician review this information
                            annually and that data be analyzed both collectively for the facility and
                            individually for each interpreting physician. The results are then to be

                             Clinical data include patient information such as demographics, risk factors, mammography results,
                            and pathology results.

                            Page 11                                                 GAO/HEHS-98-11 Mammography Services

                         used to provide feedback to the interpreting physician as part of the
                         facility’s quality assurance system. However, these regulations do not
                         include standards for measuring physician performance. FDA officials
                         stated that one of the main reasons for the general nature of FDA’s
                         requirements is that there is no consensus in the medical and scientific
                         community on the most desirable methodologies for arriving at such

Clinical Data Are        Comparable clinical data for measuring outcome changes are not available
Insufficient to Assess   for a number of reasons. Some data are available from clinical trials, CDC’s
MQSA’s Contribution to   National Breast and Cervical Cancer Early Detection Program, a
                         facility-based medical audit system, and cancer registries. However, none
Mammography              of these is an appropriate source to use in assessing MQSA’s effect on
Performance and Cancer   mammography performance and cancer outcomes.
                         Randomized clinical trials and other less comprehensive studies have
                         demonstrated that regular screening mammography can significantly
                         reduce breast cancer mortality. Such studies, while lending support to
                         using mammography as a cancer detection technique, have not reported
                         data that allow MQSA’s specific contribution to be assessed. For example,
                         the only clinical trial in the United States—New York’s Health Insurance
                         Plan Study—was conducted from 1963 to 1986 and was based on
                         equipment, imaging, and interpreting techniques that are no longer
                         applicable today.13 Also, although several community studies have shown
                         the effectiveness of mammography screening in early detection, the results
                         of each study were applicable to only one geographic area, and none of the
                         studies was current enough for a pre- and post-MQSA comparison.14

                         CDC’sNational Breast and Cervical Cancer Early Detection Program,
                         established in 1991 to provide screening services to medically underserved
                         women, has collected a fairly large volume of mammography and cancer
                         outcome data. However, the data focus on only a subset of the population

                          Four other major clinical trials have been undertaken in Sweden, two in the United Kingdom, and
                         two in Canada.
                           For example, one of the largest community studies was conducted in Albuquerque, New Mexico. The
                         study tracked mammography and pathology results of 87,433 patients from 1991 to 1993 to assess the
                         performance of community mammography screening. The study showed that community
                         mammography screening could detect breast cancer at early, treatable stages and that the distribution
                         of cancer stages was similar to that seen in successful clinical trials.

                         Page 12                                                 GAO/HEHS-98-11 Mammography Services

and are too incomplete to yield a meaningful analysis of the effect of MQSA
on cancer outcomes.15

The current MQSA requirement for a facility-based medical audit system
also has numerous limitations that prevent its consideration in developing
national measures of MQSA’s effectiveness. The fundamental limitation is
that because the data collected in this process were not intended to serve
as a mechanism for comparable reporting, little attention has been given to
ensuring data and system consistency across facilities. Each facility
decides how to collect and use the results as a quality control feedback
tool, and FDA acknowledges that, as expected, there is wide variability in
the data facilities include in their medical audits and in how they track

Problems also exist with trying to use various regional, state, and local
cancer registries to evaluate MQSA’s effects. These registries collect clinical
data on breast cancer cases, including stage and tumor size of cancer
detected. For example, the National Cancer Institute’s Surveillance,
Epidemiology, and End Results Program (SEER) has nine cancer registries
that have been in existence since 1973.16 Since 1992, CDC has also funded a
national program that establishes or improves cancer registries in states
that do not have registries such as those of the SEER program. While these
registries contain clinical data that track the status of cancer cases, they
do not collect data showing whether the cancer was detected by
mammography. Thus, they cannot be used to measure mammography
performance over time. Furthermore, while SEER cancer registry data
(which contain substantial historical data) can be used to evaluate the
trends of cancer incidence, cancer detection, and mortality, they are not
current enough to enable a pre- and post-MQSA implementation
comparison. For example, MQSA inspection of facilities began in 1995 and,
at the time of our review, the SEER registry data were only current through

 CDC’s program works with state public health agencies to provide screening, referral, and follow-up
services for underserved women. The program began with 6 states in 1991 and is currently operating in
35 states. We attempted to use CDC data to compare the cancer detection rates of the program before
and after MQSA, but several key data elements, such as history of prior mammograms and stage of
cancers, were too incomplete to be useful for our analysis.
 The program consists of nine regional population-based cancer registries covering about 14 percent
of the U.S. population.

Page 13                                                 GAO/HEHS-98-11 Mammography Services

No Clear Consensus Exists                In addition to the problems involved with the lack of data, controversy
on Appropriate Measures                  exists over how to measure mammography performance and related
for Mammography                          cancer outcomes.
Performance and Cancer

Mammography Performance                  Several performance measures are based on assessments of the extent to
Measures                                 which mammography results are accurate. The two most common
                                         measures involve sensitivity and specificity.17 Sensitivity is defined as the
                                         probability of detecting cancer when a cancer really exists, and specificity
                                         is defined as the probability of obtaining a negative mammogram when no
                                         cancer exists. The computation of these measures is shown in the
                                         following formulas:

                                         Sensitivity = True Positive/(True Positive + False Negative)

                                         Specificity = True Negative/(True Negative + False Positive)

                                         Although the definitions of sensitivity and specificity are widely accepted,
                                         calculating sensitivity and specificity is complicated by the need to know
                                         the number of true and false positives, as well as the number of true and
                                         false negatives (see table 1 for definitions).

Table 1: Definitions of True and False
Positive and Negative                    Classification of
                                         mammogram result                  Definition
                                         True positive                     Cancer diagnoseda during the specified follow-up period
                                                                           after a mammogram was interpreted as positive
                                         False positive                    No cancer diagnosed during the specified follow-up
                                                                           period after a mammogram was interpreted as positive
                                         True negative                     No cancer diagnosed during the specified follow-up
                                                                           period after a mammogram was interpreted as negative
                                         False negative                    Cancer diagnosed during the specified follow-up period
                                                                           after a mammogram was interpreted as negative
                                          Cancer is generally considered present only after being confirmed by a pathological diagnosis.

                                          Another type of performance measure uses the positive predictive values of mammograms (the
                                         proportion of women with a positive mammogram who are found to actually have breast cancer). This
                                         measure can be used with three separate definitions: it can be based on the number of cancers
                                         detected from positive mammograms, the number of biopsies recommended, and the number of
                                         biopsies performed. Using the second and third definitions would require information to be readily
                                         available about the number of positive mammograms that resulted in biopsy recommendations and the
                                         number of recommendations that actually resulted in biopsies’ being performed.

                                         Page 14                                                GAO/HEHS-98-11 Mammography Services

                          Moreover, while researchers generally accept the above definitions, they
                          have not agreed on the proper length of time for the follow-up period. For
                          example, researchers have used various follow-up time periods, ranging
                          from 7 months to over a year. Using different time periods can result in
                          different determinations of true or false positives and true or false
                          negatives. For example, if a mammogram is interpreted as negative and
                          the follow-up period is 12 months, then the negative mammogram is
                          considered a false negative if a cancer is detected during the next 12
                          months. However, if the specified follow-up period is 7 months, then the
                          negative mammogram is considered a false negative only if a cancer is
                          detected within 7 months.

                          In addition, researchers disagree on how certain mammography results
                          should be classified. In 1992, the ACR developed the Breast Imaging
                          Reporting and Data System, which established six discrete categories for
                          interpreting physicians to use in recording the results of mammograms:
                          “needs additional evaluation,” “negative,” “benign finding,” “probably
                          benign finding,” “suspicious finding,” and “highly suggestive of
                          malignancy.”18 Although researchers generally agree that two categories
                          (“negative” and “benign finding”) should be considered to be negative
                          mammograms and that two other categories (“suspicious finding” and
                          “highly suggestive of malignancy”) should be considered positive
                          mammograms, they disagree on how the remaining categories (“needs
                          additional evaluation” and “probably benign finding”) should be

                          Standards for the follow-up time period and mammography result
                          categories are essential for consistent application of such performance

Cancer Outcome Measures   Because the ultimate goal of mammography is to reduce breast cancer
                          mortality, some studies have used mortality reduction as a measure of
                          mammography effectiveness in cancer outcomes. However, because
                          women with breast cancer generally survive longer than 5 years,
                          measuring the change in mortality reduction requires a long follow-up
                          time. This need for a long follow-up period makes it difficult to use

                            Although many interpreting physicians are using these categories, they are not required to do so
                          under MQSA. However, in FDA’s proposed final regulations, recording mammography results using
                          these categories will be required for standardization purposes.
                           The “probably benign” category is often associated with a recommendation for another mammogram
                          within 6 months.

                          Page 15                                                 GAO/HEHS-98-11 Mammography Services

                             mortality reduction as a measure for assessing MQSA’s effect on cancer
                             outcomes, since not enough time has elapsed since MQSA’s implementation.

                             As an alternative to mortality reduction rates, some researchers have used
                             the early-stage disease rate as an intermediate measure of the
                             effectiveness of mammography.20 This intermediate measure is thought to
                             be appropriate because early detection of breast cancer has been shown to
                             improve survival rates. However, considerable disagreement exists about
                             how to define early-stage cancer for measurement purposes. Perhaps the
                             most controversial problem relates to whether or not cases of carcinoma
                             in situ (CIS) should be included when measuring mammography
                             effectiveness. CIS is considered the earliest stage of breast cancer and is
                             confined to the place or site where it started. In recent years, as the
                             number of CIS cases detected by mammography has continued to increase,
                             researchers have questioned how to classify them. Some experts view CIS
                             as a very slow-growing, noninvasive tumor and contend that including CIS
                             cases as early stages of cancer will overstate the benefit of mammography
                             in reducing mortality, since a large proportion of CIS tumors never spread.
                             Others argue that some CIS tumors can grow quickly and develop into
                             serious, even fatal, disease and, therefore, CIS cases should be considered
                             early-stage cancer. Because of the above controversies, some researchers
                             now believe that the late-stage disease rate is a more appropriate
                             intermediate measure than the early-stage disease rate. However, there is
                             no clear consensus on the use of this measure either.

Consortium Is Making         To help evaluate mammography’s overall impact, MQSA called for a system
Progress in Resolving Data   that would collect a large volume of data on mammography results and
and Measurement              cancer detection from select geographical areas. In response, NCI
                             established the Breast Cancer Surveillance Consortium in 1994, which
Problems                     consists of nine federally funded research projects at sites in most of the
                             major geographical regions of the United States.21 These projects collect
                             data from affiliated area mammography practices and link mammography
                             data to cancer registry data. The Consortium’s goal is to ensure that the
                             data collected can be analyzed to address issues relating to mammography
                             performance and cancer outcomes. By the year 2000, the Consortium

                              The most widely used approach to categorizing cancers involves the use of staging classifications,
                             with the size of the tumor being one of the most important factors in determining the stage of the
                               These projects are being administered by the University of California at San Francisco, the Colorado
                             Department of Public Health and the Environment, the Norris Cancer Center, the Fred Hutchinson
                             Cancer Research Center, the Group Health Cooperative of Puget Sound, the University of New Mexico,
                             the University of North Carolina, the University of Vermont, and the University of Iowa.

                             Page 16                                                  GAO/HEHS-98-11 Mammography Services

                         expects to have data on more than 3.2 million mammography
                         examinations and more than 24,000 breast cancer cases.22 According to
                         Consortium members, the large sample is necessary to examine
                         mammography performance and cancer outcomes in different health care
                         delivery systems and regions of the country and in populations of diverse
                         race and socioeconomic status.

                         To create an effective database, the Consortium is taking the following
                         steps to overcome the kinds of data and measurement problems discussed

                     •   With regard to collecting clinical data, the Consortium has spent
                         considerable time developing a consensus on which data elements to
                         collect in order to obtain consistent and reliable data. The Consortium has
                         been using standardized data collection procedures and linkage
                         mechanisms to pool data from individual projects, but 1996 was the first
                         year common data elements were collected at all projects. The
                         Consortium has just begun some descriptive analysis using pooled data
                         from all projects; however, analysis of cancer outcomes will not begin
                         until the winter of 1998, because valid data on cases of breast cancer will
                         not be available until then.
                     •   The Consortium is also working to obtain a consensus on performance
                         measures such as sensitivity and specificity. Officials of the Consortium
                         informed us that they had just begun to test aspects of these performance
                         measures and could not tell us when they will be able to reach a

                         These efforts can help strengthen the quality of information about the
                         general efficacy of mammography in improving cancer outcomes, but they
                         are unlikely to provide substantial information about MQSA’s specific effect
                         because data are not available for a pre- and post-MQSA comparison.
                         However, the Consortium efforts may have other positive MQSA-related
                         benefits in that researchers involved with several of the nine research
                         projects are currently helping mammography facilities collect data for
                         cancer outcomes audits to meet MQSA requirements.

                         When MQSA was passed, the Congress was concerned that access to
MQSA Did Not Limit       mammography services might be limited because many providers would
Access                   choose to drop mammography services rather than upgrade operations to

                          Studies show that the incidence of breast cancer ranges from 2 to 10 cancers per 1,000
                         mammography examinations.

                         Page 17                                                 GAO/HEHS-98-11 Mammography Services

comply with the standards. This has not occurred. Facility closures, both
in anticipation of MQSA and since MQSA took effect, appear to have had no
adverse effect on access to mammography services.

We addressed the question of the initial closures in our 1995 report. In all,
404 facilities, or about 4 percent of the approximately 10,000 facilities that
were providing mammography services before MQSA was implemented, had
ceased providing mammography services during the 12 months before
MQSA became effective. On the basis of (1) a study conducted by a private
research firm under contract with FDA and (2) our interviews with state
officials, we concluded that these initial closures had no negative impact
on access to services.

To assess the impact of facility closures since MQSA implementation, FDA
asked the same contractor to do an updated study. The study, completed
in May 1997, found that 1,085 facilities had stopped offering
mammography services either temporarily or permanently between
December 15, 1994, and March 19, 1997. During the same period, 922
facilities had opened or had resumed providing services. This net loss of
163 facilities since MQSA was implemented is a relatively small number
when compared with the approximately 10,000 facilities operating before
MQSA. Further, 99 percent of the closed facilities were located within 25
miles of another certified mammography facility, and 92 percent were
within 5 miles.

To determine if the states most affected by these closures had experienced
problems with access, we conducted additional follow-up work on the
contractor’s study. For the District of Columbia and the seven states
identified in the contractor’s study as having closure rates of at least
4 percent, we asked state health officials to determine if the closure of any
facility on the list had caused access problems. No problems were
reported to us. Officials said many of the closed facilities were either
low-volume providers that did not generate enough revenue to cover the
costs of meeting MQSA requirements or poor-quality providers that could
not pass accreditation. Furthermore, in five of the seven states, more than
40 percent of the facilities identified as closed have actually continued to
provide services in some form. For example, some facilities continued to
provide services by merging with another facility or consolidating their
equipment from satellite clinics. Some other facilities contracted with
mobile service providers to continue serving their patients.

Page 18                                    GAO/HEHS-98-11 Mammography Services

                  As the Congress considers reauthorization of MQSA, two points are clear
Conclusions       with regard to assessing what the act has accomplished. First, overall,
                  MQSA has had a positive impact on the quality of mammography services
                  and no effect on access to them. In looking at the currently measurable
                  areas, such as the accreditation and inspection results, the quality of X-ray
                  images, and the extent of facility closures, the evidence is strong that the
                  quality of services has improved and that access has not been adversely
                  affected. We believe it is reasonable to attribute a large part of the quality
                  improvement to (1) MQSA processes that enforced accreditation standards
                  that were not previously followed by many facilities and (2) FDA’s annual
                  inspection process, which provides a valuable, systematic means of
                  helping ensure that these higher standards are maintained.

                  Second, quantifying MQSA’s effect on the accuracy of mammogram
                  interpretation or on the improvement in cancer outcomes is much more
                  problematic. Although data collection efforts now under way will probably
                  make it easier to monitor the quality of image interpretation and the
                  effects of mammography on cancer outcomes in the future, the absence of
                  pre-MQSA data means that analysts may not be able to fully measure how
                  the act itself has affected image interpretation and cancer outcomes.

                  In commenting on a draft of this report, Department of Health and Human
Agency Comments   Services (HHS) officials agreed with our presentation of the issues. In
                  addition, ACR officials provided some technical comments, which we
                  incorporated as appropriate. Appendix III contains the full text of HHS’

                  Page 19                                    GAO/HEHS-98-11 Mammography Services

We are sending copies of this report to the Secretary of Health and Human
Services, the Commissioner of the Food and Drug Administration, the
Director of the National Cancer Institute, the Director of the Centers for
Disease Control and Prevention, the Director of the Office of Management
and Budget, and other interested parties. We will also make copies
available to others on request.

Please contact me at (202) 512-7719 if you or your staff have any questions.
Other GAO contacts and staff acknowledgments are listed in appendix IV.

Bernice Steinhardt
Director, Health Services, Quality
  and Public Health Issues

Page 20                                   GAO/HEHS-98-11 Mammography Services
Page 21   GAO/HEHS-98-11 Mammography Services

Letter                                                                                           1

Appendix I                                                                                      24

Scope and
Appendix II                                                                                     26

Follow-Up on Our
January 1997 Report
Appendix III                                                                                    28

Comments From the
Department of Health
and Human Services
Appendix IV                                                                                     29

GAO Contacts and
Appendix V                                                                                      30

Tables                 Table 1: Definitions of True and False Positive and Negative             14
                       Table II.1: Summary of Recommendations and FDA Actions                   27

Figures                Figure 1: Size of Breast Tumors Found by Mammography and                  4
                       Figure 2: Low- and High-Quality Mammography Images of the                 5
                         Same Patient
                       Figure 3: Comparison of Mammography Facilities’ Inspection                9
                         Results, Fiscal Years 1995-97

                       Page 22                                  GAO/HEHS-98-11 Mammography Services


ACR        American College of Radiology
CDC        Centers for Disease Control and Prevention
CIS        carcinoma in situ
FDA        Food and Drug Administration
HHS        Department of Health and Human Services
MQSA       Mammography Quality Standards Act of 1992
NCI        National Cancer Institute
NEXT       Nationwide Evaluation of X-ray Trends
SEER       Surveillance, Epidemiology, and End Results Program

Page 23                                GAO/HEHS-98-11 Mammography Services
Appendix I

Scope and Methodology

             To assess whether the Food and Drug Administration’s (FDA)
             implementation of the Mammography Quality Standards Act of 1992
             (MQSA) has resulted in improvement in the quality of mammography
             services, we relied on three analyses: the American College of Radiology’s
             (ACR) accreditation results, FDA’s annual inspection results, and FDA’s
             pre-MQSA surveys of mammography equipment performance. Specifically,
             we obtained and reviewed data on ACR’s accreditation failure rates and
             reasons for failures for each fiscal year from 1995 to 1997. In addition, we
             analyzed the results of FDA’s annual inspections that took place between
             January 1995 and June 1997 at about 10,000 mammography facilities
             nationwide. To assess improvement in the quality of X-ray images, we
             compared pre- and post-MQSA phantom image scores using data from the
             Nationwide Evaluation of X-ray Trends (NEXT) surveys and FDA’s annual
             inspections. The NEXT surveys collected data on the technical performance
             of mammography, including such things as phantom image scores,
             radiation dose, and existence of darkroom fog (excessive light that fogs
             the image). We considered the phantom image scores from pre-MQSA NEXT
             surveys to be the baseline for comparison with the phantom image scores
             from post-MQSA annual inspections. Although we did not perform a
             reliability assessment of FDA’s data systems, we conducted several data
             tests and found FDA’s data to be adequate to meet our objectives.

             To assess whether MQSA has improved the early detection of breast cancer,
             we reviewed numerous studies and analyses on the accuracy of physician
             interpretation, breast cancer incidence and mortality, and mammography’s
             effectiveness in cancer detection. We also interviewed many
             mammography and cancer experts; researchers; and officials from FDA, the
             National Cancer Institute (NCI), and the Centers for Disease Control and
             Prevention (CDC) to discuss mammography performance and cancer
             outcome measures, as well as the availability of current and future data to
             assess performance and outcome improvement. In addition, we consulted
             with members of NCI’s Breast Cancer Surveillance Consortium who
             provided a written response to our questions on the methodological and
             data problems in measuring mammography performance and assessing
             MQSA’s impact on cancer outcomes.

             To assess MQSA’s effect on accessibility, we examined an FDA contractor’s
             study on newly opened and newly closed mammography facilities, by
             state, between December 1994 and March 1997. We supplemented this
             work by interviewing state radiation control program officials in seven
             states—California, Colorado, Florida, Kansas, New Hampshire, North
             Dakota, and Virginia—and the District of Columbia to discuss why

             Page 24                                   GAO/HEHS-98-11 Mammography Services
Appendix I
Scope and Methodology

facilities in their localities closed and the impact that these closures had
on access to mammography services.

Page 25                                    GAO/HEHS-98-11 Mammography Services
Appendix II

Follow-Up on Our January 1997 Report

              In our January 1997 report reviewing FDA’s mammography inspection
              program,23 we identified several issues that needed management attention
              with regard to conducting inspections and following up on deficiencies.
              FDA generally agreed with our recommendations and has taken action on
              all of them. The following table summarizes the problems, our
              recommendations, and the actions that FDA has taken in response.

                GAO/HEHS-97-25, Jan. 27, 1997.

              Page 26                                 GAO/HEHS-98-11 Mammography Services
                                  Appendix II
                                  Follow-Up on Our January 1997 Report

Table II.1: Summary of
Recommendations and FDA Actions   Problems we found                Our recommendations              FDA’s actions
                                  Inspection results varied        Monitor the inspection           FDA distributed new
                                  considerably from state to       results more closely to          inspection software to
                                  state. It was not clear          ensure consistent reporting      monitor inspection results
                                  whether the differences were     of violations and corrections.   more closely. FDA also
                                  due to variations in the                                          conducted additional
                                  quality of mammography at                                         training of staff who audit
                                  different facilities or the                                       the performance of MQSA
                                  inspectors’ approaches in                                         inspectors to ensure
                                  conducting inspections and                                        consistent application of
                                  reporting results.                                                inspection procedures.
                                  We found variability in how      Strengthen procedures for        FDA implemented an
                                  inspectors scored phantom        assessing image quality by       annual program to test
                                  images.                          providing additional             MQSA inspectors on
                                                                   inspector training and           phantom image scoring.
                                  FDA had no procedure in          Protect patients from risk of    FDA established a policy
                                  place for clinical image         poor mammograms by               that allows it to initiate a
                                  review or patient notification   requiring follow-up clinical     clinical image review and
                                  when evidence suggested          image reviews and patient        patient notification when
                                  problems with the quality of a   notification when                serious violations are found.
                                  facility’s mammograms.           inspections detect serious
                                  When violations posed a          Develop procedures for (1)       FDA issued guidance to
                                  serious health risk, FDA did     determining when the             compliance officers to
                                  not have criteria to help        health risk is serious           establish the criteria and
                                  determine when to require        enough to justify the            procedures necessary to
                                  the immediate suspension of      immediate suspension of a        determine the degree of
                                  a facility’s certificate.        facility’s certificate and (2)   health risks and when to
                                                                   implementing the                 seek suspension of a
                                                                   suspension.                      facility’s certificate.
                                  FDA’s follow-up efforts did      Reevaluate the                   FDA revised its policy
                                  not always ensure that           classification and               guidance to strengthen its
                                  corrective actions were taken    enforcement policy for level     procedures for addressing
                                  on less serious violations.      3 violations.                    less serious violations that
                                                                                                    recur from one inspection to
                                  FDA’s compliance system          Make complete, up-to-date        FDA distributed an
                                  was inadequate in three field    information on violations        automated compliance
                                  offices included in our review   accessible to compliance         information system that
                                  because staff did not have       personnel.                       provides current information
                                  direct access to inspection                                       on inspection violations.

                                  Page 27                                              GAO/HEHS-98-11 Mammography Services
Appendix III

Comments From the Department of Health
and Human Services

               Page 28      GAO/HEHS-98-11 Mammography Services
Appendix IV

GAO Contacts and Staff Acknowledgments

                  Frank Pasquier, Assistant Director, (206) 287-4861
GAO Contacts      Sophia Ku, Evaluator-in-Charge, (206) 287-4888

                  In addition to those named above, the following individuals made
Staff             important contributions to this report: Donna Bulvin, Senior Evaluator;
Acknowledgments   Susan Lawes, Senior Social Science Analyst; Stan Stenersen, Senior
                  Evaluator; Evan Stoll, Computer Specialist; and Craig Winslow, Senior

                  Page 29                                  GAO/HEHS-98-11 Mammography Services
Appendix V


             We would like to acknowledge the members of the NCI’s Breast Cancer
             Surveillance Consortium and officials from CDC’s Division of Cancer
             Prevention and Control for their advice and technical assistance on the
             methodological and data problems of measuring mammography
             performance and cancer outcomes.

(108310)     Page 30                                  GAO/HEHS-98-11 Mammography Services
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