Jan 20, 1995 - data. Screening mammography and clini- cal breast examination can reduce breast cancer mortality-3 ... SUDAAN (Survey Data Analysis) soft- ware was used to ..... Cervical Cancer Screening Programs. TABLE 3-Reported ...
the Use of Cervical, Breast, and Colorectal Cancer Screening Increased in the United States?
Has
Laurie M. Anderson, PhD, MPH, and Daniel S. May, PhD
Introdtion The benefits of screening for selected known from clinical trials, case-control studies, and, in the case of the Papanicolaou (Pap) test, historical data. Screening mammography and clinical breast examination can reduce breast cancer mortality-3; use of the Pap test can reduce mortality from invasive cervical cancer4; and procedures for the early detection of colorectal cancer, such as fecal occult blood testing, proctoscopy, and digital rectal examination, may also reduce mortality.5'6 However, reducing mortality through cancer screening can be fully realized only if the screening tests are acceptable to the population and are repeated at appropriate intervals to detect disease at an early stage.7 This report describes the use of cervical, breast, and colorectal cancer screening modalities within the US population in 1987 and 1992 as reported in the National Health Interview Survey, Cancer Control Supplement.8'9 The purpose is to assess trends in the use of these tests, especially among sociodemographic subcancers are
groups.
Methods The National Health Interview SurCancer Control Supplement, contains data obtained through interviews with a sample of the civilian, noninstitutionalized US population aged 18 or older using a multistage sample design.8'9 The number of persons interviewed for the 1987 survey was 22 043 and for the 1992 survey, 12 035. The 1992 sample was smaller because budgetary constraints prompted discontinuation of the cancer supplement interviews after the 28th week of that year.9 The 1987 and 1992 surveys ascertained cancer screening knowledge and practices as follows: Women aged 18 and older were asked about their use of the Pap test; women aged 40 and older, about their use of mammography and clinical breast examination; and men and women aged 40 and older, about their use of
vey,
proctoscopic examination, digital rectal examination, and fecal occult blood testing. For each of the six cancer screening tests, the number of persons in the appropriate sex-age group who had ever had the test done and the time since their last test were determined. Screening tests were distinguished from diagnostic tests by asking respondents whose most recent test was within 3 years of the interview the reason for their last test. In 1987, respondents were asked if their last test was done because of a health problem. For purposes of this analysis, it was assumed that those who answered no received the test for screening purposes. In 1992, the respondents were asked the main reason they had had the test and were given multiple-choice answers. Screening exams were determined from responses that the test was part of a routine physical exam, was a screening test, or was a baseline test (asked for mammography only). Clinically recommended screening intervals and age guidelines vary for the six tests discussed in this report; for simplicity of presentation, however, 1and 3-year intervals are presented for the screening modalities reported by persons aged 50 and older and, for the Pap test, by those aged 18 and older. To take into account the design of the complex, multistage sample, SUDAAN (Survey Data Analysis) software was used to calculate the population estimates, their standard errors, and the standard errors of differences between pairs of estimates.10
Laurie M. Anderson is with the Office of Surveillance and Analysis and Daniel S. May is with the Division of Cancer Prevention and Control at the National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Ga. Requests for reprints should be sent to Laurie M. Anderson, Mailstop K-30, Centers for Disease Control and Prevention, 1600 Clifton Rd NE, Atlanta, GA 30333. This paper was accepted on January 20, 1995.
June 1995, Vol. 85, No. 6
Public Health Briefs
Results In 1992, 35% of women aged 50 and older, or twice the proportion reported in 1987, reported having had a screening mammogram within the past year (Table 1). A doubling was also observed in screening reported within the previous 3 years. Recent Pap smear screening reported by women aged 18 and older remained basically the same in 1987 and 1992. Among the colorectal cancer screening modalities, the proportion of the population screened in the past year increased by less than 5% between 1987 and 1992 for each of the three tests reported. One third of the 1992 survey respondents aged 50 and older had never heard of proctoscopic screening for colorectal cancer, a proportion also observed in 1987.
Screening Trends among Sociodemographic Subgroups Reported cancer screening within the past 3 years increased significantly between 1987 and 1992 for five of the six test modalities in most sociodemographic subgroups (Table 2). Exceptions are noted below. Breast cancer screening. Mammography screening increased among all age groups. Women over age 75 continue to report less screening than women aged 50 to 74; however, the greatest percentage gain between the reporting periods ([19921987] * 1987) was in the oldest age group. The difference in reported mammography screening between Black and White women disappeared by 1992. On the other hand, reported screening among Hispanic women remained below that of non-Hispanics. Higher levels of education were associated with a greater likelihood of reported mammography. A striking gap was also evident between women living above and those living below the poverty level. Women in rural areas continued to report less breast cancer screening than did women residing in urban areas. Cervical cancer screening. Women in older age groups reported considerably lower use of the Pap test than did younger women (Table 3). Hispanic women reported less Pap testing than did nonHispanic women, although the difference decreased considerably between 1987 and 1992. Women with more than a high school education, women living above the poverty level, and women residing in urban areas continued to report more June 1995, Vol. 85, No. 6
TABLE 1-Survey Population according to Screening Status, Year, and Weighted Population Estimates' of Persons Aged 50 Years or Older (18 or Older for Pap Smear)
Test and Year
Mammography 1987 1992 Clinical breast examination 1987 1992 Pap smear 1987 1992 Proctoscopy 1987 1992 Digital rectal examination 1987 1992 Fecal occult blood test 1987 1992
Never Heard of Test, % Sample
Heard of Test, % Never Had Ever Had Test Test
Most Recently Screened in the Past, % 3 Years
1 Year
5 052 2 709
17.2 10.4
46.0 22.5
36.9 67.1
22.6 48.8
16.5 35.3
5052 2 709
10.1 ... b
11.1 12.4
78.8 87.6
56.2 61.1
41.6 46.0
3.9 b
7.1 8.7
89.0 91.3
64.6 65.4
48.6 49.3
8 240 4 428
34.1 32.1
39.7 34.8
26.2 33.1
6.4 9.4
3.3 4.7
8 240 4 428
21.0 17.7
18.5 20.1
60.5 62.2
30.7 35.7
21.3 25.8
8 240 4 428
17.0 16.7
41.6 34.9
41.4 48.4
21.7 26.3
14.9 17.3
12 868 6 981
...
aStandard errors of the estimates ranged from 0.2 to 1.1. bRespondents were not asked if they had heard of clinical breast examination or Pap smear in 1992. Those responding that they had never had the exam are in the "Heard of but Never Had" column.
cervical
cancer
screening than did their
by 1990.11 In addition, breast
cancer
counterparts. Overall, no significant
screening increased
changes in Pap testing in the demographic subgroups were observed from 1987 to 1992 except for a decrease among women with 12 years of education. Colorectal cancer screening. More men than women reported having had a screening proctoscopic examination in the past 3 years (Table 2). Such examinations increased more among older persons whereas digital rectal examination decreased with age; however, no age trend was observed for fecal occult blood testing. Use of all three colorectal screening modalities was lower among Hispanics than among non-Hispanics and was higher
specifically, lower income, less educated, and rural women-that historically have had limited access to preventive health services. Despite this progress, several public health challenges remain. Pap testing at regular intervals should continue to be emphasized. Clearly, colorectal cancer screening tests are not used as often as are other cancer screening modalities. This finding, unlike that for the Pap test and mammogram, may be owing to less consensus among providers about the benefits of recommending these procedures to their patients. Further demonstration of and education about the efficacy of colorectal cancer screening modalities may be required. Most striking are the continued disparities in the use of cancer screening
among those with more years of education. Persons living above the poverty level reported more screening than those living below. A similar relationship was found for urban and rural residents.
Discussion Between 1987 and 1992, use of mammography showed large gains, particularly among Black women; however, much of the increase was already evident
among groups-
tests in the United States between those living above and those living below the poverty level, between the more educated and the less educated, and between those living in urban areas and those living in
rural areas. O
American Journal of Public Health 841
Public Health Briefs
TABLE 2-Reported Use of Breast and Colorectal Cancer Detection Tests for Screening In the Past 3 Years among People' Aged 50 and Older, by Sociodemographic Group, 1987 and 1992
TABLE 3-Reported Use of Pap Test In the Past 3 Years among Women Aged 18 and Older, by Sociodemographic Group, 1987 and 1992
Fecal Digital Occult MammogBreast ProctosRectal Blood raphy Examination copy Examination Test
Clinical
Sex Female
1987 1992 1987 1992
22.6 48.8*
1987 1992 1987 1992 1987 1992
26.0 54.5* 21.9 48.8* 15.2 35.0*
1987 1992 1987 1992
1987 1992 Non-Hispanic 1987 1992 Education, y < 12 1987 1992 12 1987 1992 > 12 1987 1992 Poverty levelb 1987 Above 1992 Below 1987 1992 1987 Unknown 1992 Residence Rural 1987 1992 Urban 1987 1992
Male Age, y 50-64 65-74
75+
Race Black
White Ethnicity Hispanic
56.2 61.1 *
12.1*
32.0 35.5* 29.1 36.0*
22.8 26.9* 20.3 25.4*
62.2 66.0 52.2 61.5* 46.3 48.8
5.7 8.5* 8.0 10.0 5.7 1 1.0*
31.0 37.6* 32.7 36.9* 26.3 28.9
21.1 25.5* 24.7 28.1 18.4 25.6*
19.0 50.4* 23.2 48.8*
52.1 64.2* 57.0
61.1*
4.0 10.3* 6.7 9.4*
23.5 31.0* 31.9 36.5*
15.8 22.4* 22.4 26.6*
17.7 44.7* 22.9 48.9*
51.7 58.6 56.4 61.2*
2.2 8.1* 6.6 9.5*
21.2 22.7 31.2 36.3*
12.4 16.9 22.1 26.7*
14.8 35.5* 25.4 52.0* 31.0 61.2*
46.1 53.8* 60.7 61.6 65.6 70.1
3.5 6.6* 6.4 8.6* 10.6 13.7*
22.8 24.9 32.7 35.2 39.8 48.2*
14.7 19.3* 22.7 25.3 30.8 35.2*
24.8 53.7* 10.8 27.0* 18.0 36.0*
59.6 64.3* 38.4
7.0 10.3* 2.3 5.3*
33.0 38.6* 16.4 21.6 23.6 25.9
23.7 28.8* 9.7 14.9* 14.7 17.2
16.5 43.6* 24.8 50.5*
48.2 58.0* 59.0 62.2*
25.7 30.6* 32.4 37.4*
16.8 19.8 23.4 28.4*
49.1* 47.6 51.5
5.6 7.3* 7.3
4.2 6.1
5.2 8.5* 6.8
9.7*
Note. Data come from the National Health Interview Survey, Cancer Control Supplements, 1987 and 1992. aMammography and clinical breast examination percentages are based on female respondents
only. bPoverty status calculations are based on family income, family size, and number of children younger than 18 years. Subjects in the "Unknown" category did not state their income. *Significantly different between 1987 and 1992 (P < .05).
Age, y 18-39 40-49 50-64 65-74 75+ Race Black White Ethnicity Hispanic Non-Hispanic Education, y < 12 12 > 12 Poverty level Above Below Unknown Residence Rural Urban
1. Shapiro S, Venet W, Strax P, Roeser R. Selection, followup, and analysis in the Health Insurance Plan Study: a randomized trial with breast cancer screening. Natl Cancer Inst Monogr. 1985;67:56-74. 2. Tabar L, Fagerberg CJG, Gad A, et al. Reduction in mortality from breast cancer after mass screening with mammography. Lancet. 1985;1:829-832.
842 American Journal of Public Health
3. Verbeek ALM, Hendricks JHCL, Holland R, Mravunac M, Sturmans F, Day NE. Reduction of breast cancer mortality through mass screening with modem mammography: first results of the Nijmegen Project, 1975-1981. Lancet. 1984;1:12221224. 4. International Agency for Research on Cancer, Working Group on Evaluation of Cervical Cancer Screening Programs.
%1992
72.2 68.5 60.5 50.6 35.8
71.8 70.6 63.2 54.0 35.8
67.5 64.6
71.6 64.9
57.1 65.2
62.6 65.6
47.2 66.6 74.0
48.7 63.7* 76.0
67.4 52.4 52.2
68.2 57.3 52.0
61.6 65.5
59.6 67.0
Note. Data come from the National Health Interview Survey, Cancer Control Supplements, 1987 and 1992. *Signiflcantly different between 1987 and 1992 (P < .05).
5. 6.
7.
8.
9.
References
%1987
Screening for squamous cervical cancer: duration of low risk after negative results of cervical cytology and its implication for screening policies. BrMed J. 1986;293:659664. DeCosse JJ, Tsioulias GJ, Jacobson JS. Colorectal cancer: detection, treatment, and rehabilitation. CA. 1994;44:27-42. Mandel JS, Bond JH, Church TR, et al. Reducing mortality from colorectal cancer by screening for fecal occult blood. NEnglJ Med. 1993;328:1365-1371. Morrison AS. Screening in Chronic Disease. New York, NY: Oxford University Press; 1985. 1987National Health Interview Survey Cancer Control Public Use Record. Hyattsville, Md: National Center for Health Statistics; 1989. 1992 National Health Interview Survey Cancer Control Public Use Record. Hyattsville, Md: National Center for Health Statistics;
1994. 10. SUDAAN Survey Data Analysis Software. Research Triangle Park, NC: Research Triangle Institute; 1991. 11. Breen N, Kessler L. Changes in the use of screening mammography: evidence from the 1987 and 1990 National Health Interview Surveys. Am J Public Health. 1994;84: 62-67.
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