Cervical screening: time to change the policy

James A Dickinson
Med J Aust 2002; 176 (11): 547-550. || doi: 10.5694/j.1326-5377.2002.tb04553.x
Published online: 3 June 2002
Australian national policy

Reaching consensus on a national policy was not easy. In 1985 the National Health and Medical Research Council adopted a three-yearly cervical screening policy,2 but this was largely ignored. Estimates given by the International Agency for Research on Cancer in 1986 suggested that three-yearly screening would prevent about 90.8% of squamous cervical cancer, two-yearly screening 92.5%, and annual screening 93.5%.3 Thus, in doing two to three times as many smears, with all the burden this entails, the gain in cancers prevented by annual smears is marginal. A consensus development meeting held in 1988 under the auspices of the Australian Cancer Society agreed that the scientific evidence supported three-yearly screening. A major evaluation program on the current state of screening then culminated in a report to the Australian Health Ministers' Advisory Council (AHMAC).4 The report showed that 55%–65% of women under 50 years had a smear within two years, and these rates were higher among young urban women, but low among older and rural women, including Indigenous and migrant women. More than half the cost of the program went into follow-up services rather than smear-taking and reporting. The AHMAC report suggested that a longer interval between smears, better quality of smears, and greater effort to reach underserved groups would improve the effectiveness of the screening program without increasing costs. However, many gynaecologists, pathologists and a few women's groups were unwilling to accept the recommendation of a three-year interval because of concerns about lack of sensitivity, the quality of smears and their interpretation, and assertions that without reminder services and follow-up such a long interval would be unsafe.

The outcome was that in 1990 a two-year interval was adopted, not by consensus, but by political intervention. It was intended to be temporary, until the full program of quality assurance was in place and fail-safe reminder services were available through State screening cytology registers — a process expected to take about three years. However, establishment of the registers took longer than expected. Indeed, the final one (in Queensland) only came online in 1999.5 In 1994, an early evaluation of the program recommended that the policy not be changed at that time, but suggested review within five years.6

All the planned activities of the national program are now in place, including regular evaluation. Pathology quality assurance is now substantially improved and a uniform reporting system is used. The proportion of women being screened is steadily rising.5 Most doctors and women now seem to accept the two-year interval, although some laboratories continued to recommend annual smears for many patients until accreditation regulations required them to recommend two-yearly follow-up for all negative smears.7 Thus, a substantial number of women are still having annual smears.7,8

Recent research has shown that the absence of endocervical cells on a smear does not necessarily mean a greater chance of developing cancer and therefore does not require an early repeat smear.9

Other national policies

Most countries with national policies recommend a three-year interval between Pap smears (see Box 2). The United States and Germany are now the only countries in which certain government or professional bodies recommend annual smears,10,14 although the US Preventive Services Task Force and the American Academy of Family Physicians both recommend "at least three-yearly" smears.12,13 Canada also has varying recommendations. Finland is notable for its five-year interval, which, since its introduction in 1963, has led to a 90% reduction in squamous cervical cancer incidence.19 Finland's experience shows that, for an effective program, ensuring full population coverage is more important than frequent smears. The United Kingdom, with a 3–5-year interval, launched an organised approach in 1988 with incentives for general practitioners. This has led to a dramatic drop in invasive cancer incidence compared with the previous "unorganised" approach.20,21 Thus, Australia's current two-year interval is at the "more frequent" end of the policy range relative to other Western countries with effective programs.

Age for commencing screening

The recommended age for starting screening is also variable (Box 2). The American Cancer Society and the American College of Obstetricians and Gynecologists recommend screening all women from age 18, even if they have not commenced sexual activity — a recommendation that must surely be ignored by most doctors. UK guidelines recommend screening from age 20, while the European group recommends "screening should start at the latest before the age of 30 years and definitely not before 20 years".22

Starting too early may cause considerable morbidity as a result of the procedures used to investigate false positive results. Over half of a sample of US college women contracted papillomavirus infections in the first few years after commencing sexual activity, but most of these infections resolved spontaneously within a year.23 One in every 13 smears in women under the age of 25 leads to colposcopy,24,25 which may result in biopsy and treatment. High-grade cytological abnormalities are diagnosed in about 1.4% of women screened under the age of 25, although the risk of invasive disease at this age is extremely low5 and the majority of these abnormalities will regress without treatment.26 While doctors are pleased to find and treat an abnormality, such intervention is only helpful to the small fraction of women whose changes would progress to cancer. Minor abnormalities that come and go are unimportant and can cause unnecessary alarm. While treatment of some papillomavirus infections is useful for symptom control, this does nothing to prevent the incorporation of high-risk wart virus into the genome of cervical cells, or the subsequent development of cancer. It would be better to commence screening after this period of initial viral reactions, as our current understanding is that the malignant process usually takes more than 10 years to develop24 after infection with specific papillomavirus types.26,27 The proportion of abnormal smears decreases with age, but abnormalities among older women have a much greater chance of leading to true malignancy.24

Objections to policy change

Objections to longer intervals and higher commencement age include the low sensitivity of smears, errors in detection, the possibility of a rapid-onset variant of cancer in young women, clinical presentation of some cancers after screening, and the apparent increase in adenocarcinoma.28

While one 1995 meta-analysis suggested that a single smear may have a sensitivity as low as 30%–50%,29 a more recent study has estimated sensitivities in the range 51%–88%.30 Moreover, the power of the screening program comes from repeated opportunities to screen during the long pre-invasive phase. Even when carefully sought, little evidence can be found for accelerated disease among young women.26,31 Besides, screening programs only work effectively for chronic, slowly developing diseases — screening for rapidly invasive cases is futile. Any screening program will miss some squamous cell cancers, as a pathology report reflects cell morphology at an arbitrary point in a spectrum of changes and depends greatly on judgement, whether it be by humans or by machines. The theoretical maximum preventive ability is slightly over 90%.3,30

Adenocarcinoma of the cervix usually represents only a small proportion of cervical cancers, but Pap smears cannot reliably detect it, so they have little effect on its incidence. As the incidence of invasive squamous cancer decreases, the apparent proportion of adenocarcinomas will increase, as it has done in Finland.19

Effect on women of having Pap smears

Having a cervical smear is an uncomfortable procedure, and some women find it embarrassing and demeaning.32,33 One would therefore expect that women would prefer a less frequent screening interval and fewer smears in their lifetime. In the absence of screening, perhaps at worst only one in 50 Australian women would get cervical cancer over their lifetime, so the 98% who would not get this cancer will never benefit from screening. On the other hand, there are definite risks associated with having a "positive" smear result — over a lifetime, annual smears appear likely to expose 75% of women to having colposcopy.25 These women are referred for further investigation, and often for biopsy and ablative therapy. While gynaecologists regard these as "minor procedures", women find them unpleasant, and the healing process may take several weeks.34 There is also a small risk of complications, including cervical stenosis. Some women misunderstand the implications of a positive smear, and may think they have cancer,35,36 while some develop definite psychological distress.35-37

New technologies for taking and reading smears promise greater sensitivity, but their reduced specificity leads to more false positives.29,30

As the frequency of smears increases, the benefits (in terms of detection and prevention of cancers) increase only marginally, while costs and potential harm rise substantially.30 Therefore, reducing the amount of unnecessary treatment by reducing the frequency of smears and starting them at a later age is worthwhile, provided this does not substantially increase the chance of untreatable invasive cancer.

Making change

After 10 years, the time has come to change to a three-year interval, and to start screening at age 25, or several years after sexual activity commences.

Such a change may prove difficult to implement. It will require rethinking the reminder interval for the smear registries, and a certain amount of reprogramming. It would reduce cost,5 although some claim that economic arguments are not relevant when women's lives are at stake. Even accepting that premiss, greater value per dollar and less chance of harm would be obtained by rediverting energy and funding to currently underserved and high-risk groups of women. Mechanisms to reward practitioners for population screening coverage might require amendment to focus their activity better. Perhaps some of the savings made by increasing the interval between smears could go towards increasing the Medicare rebate for women who have smears at the recommended interval.

Doctors and pathology laboratories who have always been opposed to the two-year interval will have even more difficulty accepting the three-year interval, but this reluctance is largely based on emotion rather than science. Fearing legal censure and citing the O'Shea case,38 some laboratories have been recommending that doctors screen more frequently than two-yearly.8 However, the court case in question was about failure to refer for postcoital bleeding and inadequate laboratory standards and is irrelevant for those who follow the screening guidelines. Mandatory performance standards for laboratories, which from 1999 have required that a reminder notice be issued at two-yearly intervals after normal smears, should change the recommended interval to three years.

One might even ask whether it is ethical to recommend more frequent smears without giving full information and obtaining proper consent. Young, educated urban women, who are currently the group most likely to have smears at less than two-yearly intervals, should be informed through publicity campaigns that this is unnecessary and may be harmful. While a woman may request more frequent smears, there is no obligation on the rest of the population to encourage and subsidise this through Medicare.

Clearly, a policy change cannot be made instantaneously, and will require consideration and consultation, but, once again, achieving consensus is unlikely. It may require another political decision!

  • James A Dickinson

  • Department of Community and Family Medicine, The Chinese University of Hong Kong, Sha Tin, New Territories, Hong Kong.


Competing interests:

None declared.

  • 1. Cervical Cancer Prevention Taskforce. Screening for the prevention of cervical cancer. Canberra: Department of Health, Housing and Community Services, 1991.
  • 2. National Health and Medical Research Council Report. Frequency of cervical cytology. Med J Aust 1985; 142: 275.
  • 3. IARC Working Group on evaluation of cervical cancer screening programmes. Screening for squamous cervical cancer: duration of low risk after negative results of cervical cytology and its implication for screening policies. BMJ 1986; 293: 659-664.
  • 4. Australian Health Ministers' Advisory Council. Cervical Cancer Screening Evaluation Committee. Cervical cancer screening in Australia: options for change. Canberra: Australian Institute of Health, 1991. (Prevention Program Evaluation Series No. 2.)
  • 5. Australian Institute of Health and Welfare. Cervical screening in Australia 1997-1998. Canberra: AIHW, 2001. (Catalogue No. CAN 9. Cancer Series No. 14.)
  • 6. Guest C, Griffith L, Lewis Y, Moulding N. Evaluation of the organised approach to preventing cancer of the cervix. Screening policy, recruitment and participation. Report to the Commonwealth Department of Human Services and Health. Adelaide: Cervical Screening Program Steering Committee, Department of Community Medicine, University of Adelaide, 1994.
  • 7. Mitchell H, Hocking J. Predictors of early rescreening in the National Cervical Screening Program, Australia. Aust N Z J Public Health 2001; 25: 334-338.
  • 8. Morris KA, Kavanagh AM, Gunn JM. Management of women with minor abnormalities of the cervix detected on screening: a qualitative study. Med J Aust 2001; 174: 126-129.
  • 9. Mitchell HS. Longitudinal analysis of histologic high-grade disease after negative cervical cytology according to endocervical status. Cancer 2001; 93: 237-240.
  • 10. Smith RA, Eschenbach AC, Wender R, et al. American Cancer Society guidelines for the early detection of cancer: update of early detection guidelines for prostate, colorectal, and endometrial cancers. CA Cancer J Clin 2001; 51: 38-75.
  • 11. American Cancer Society. Summary of American Cancer Society recomendations for the early detection of cancer in asymptomatic people. CA Cancer J Clin 1993; 43: 42-46.
  • 12. Zoorob R, Anderson R, Cefalu C, Sidani M. Cancer screening guidelines. Am Fam Physician 2001; 63: 1101-1112.
  • 13. Screening for cervical cancer. In: U.S. Preventive Services Task Force. Guide to clinical preventive services. 2nd ed. Baltimore: Williams and Wilkins, 1996.
  • 14. van Ballegooijen M, Akker-van Marle E, Patnick J, et al. Overview of important cervical cancer screening process values in European Union (EU) countries, and tentative predictions of the corresponding effectiveness and cost-effectiveness. Eur J Cancer 2000; 36: 2177-2188.
  • 15. Ontario Cervical Screening Collaborative Group. New cervical screening guidelines issued to Ontario physicians. Ontario Medical Review December 1996; 40-44.
  • 16. British Columbia Cancer Agency. Personal questions on cervical cancer screening. Available at: <>. Accessed 29 April 2002.
  • 17. Canadian Task Force on the Periodic Health Examination. The Canadian guide to cinicial preventive health care. Ottawa: Canada Communication Group, 2001.
  • 18. Recommendations for cervical screening 1997. Members of the Working Party on Cervical Screening. N Z Med J 1998; 111: 94-98.
  • 19. Nieminen P, Kallio M, Hakama M. The effect of mass-screening on incidence and mortality of squamous and adenocarcinoma of cervix uteri. Obstet Gynecol 1995; 85: 1017-1021.
  • 20. Gibson L, Spiegelhalter DJ, Camilleri-Ferrante C, Day NE. Trends in invasive cervical cancer incidence in East Anglia from 1971 to 1993. J Med Screen 1997; 4: 44-48.
  • 21. Sasieni P, Adams J. Effect of screening on cervical cancer mortality in England and Wales: analysis of trends with an age period cohort model. BMJ 1999; 318: 1244-1245.
  • 22. Advisory Committee on Cancer Prevention. Recommendations on cancer screening in the European union. Eur J Cancer 2000; 36(12): 1473-1478.
  • 23. Ho GY, Bierman R, Beardsley L, et al. Natural history of cervicovaginal papillomavirus infection in young women. N Engl J Med 1998; 338: 423-428.
  • 24. Holowaty P, Miller AB, Rohan T, To T. Natural history of dysplasia of the uterine cervix. J Natl Cancer Inst 1999; 91: 252-258.
  • 25. Kavanagh AM, Santow G, Mitchell H. Consequences of current patterns of Pap smear and colposcopy use. J Med Screen 1996; 3: 29-34.
  • 26. Olamijulo J, Duncan ID. Is cervical cytology screening of teenagers worthwhile? Br J Obstet Gynaecol 1995; 102: 515-516.
  • 27. van Oortmarssen GJ, Habbema JD. Duration of preclinical cervical cancer and reduction in incidence of invasive cancer following negative pap smears. Int J Epidemiol 1995; 24: 300-307.
  • 28. Australian Medical Association Federal Council. AMA discussion paper on cervical cancer screening. Canberra: AMA, 2001.
  • 29. Fahey MT, Irwig L, Macaskill P. Meta-analysis of Pap test accuracy. Am J Epidemiol 1995; 141: 680-689.
  • 30. Myers ER, McCrory DC, Subramanian S, et al. Setting the target for a better cervical screening test: characteristics of a cost-effective test for cervical neoplasia screening. Obstet Gynecol 2000; 96: 645-652.
  • 31. Wain GV, Farnsworth A, Hacker NF. Cervical carcinoma after negative pap smears — evidence against rapid-onset cancers. Int J Gynecol Cancer 1992; 22: 318.
  • 32. Holroyd E, Twinn SF, Shia AT. Chinese women's experiences and images of the Pap smear examination. Cancer Nurs 2001; 24: 68-75.
  • 33. Shelley JM, Irwig LM, Simpson JM, Macaskill P. Evaluation of a mass-media-led campaign to increase Pap smear screening. Health Educ Res 1991; 6: 267-277.
  • 34. Harper DM, Mayeaux EJ, Daaleman TP, Johnson CA. Healing experiences after cervical cryosurgery. J Fam Pract 2000; 49: 701-706.
  • 35. Jones MH, Singer A, Jenkins D. The mildly abnormal cervical smear: patient anxiety and choice of management. J R Soc Med 1996; 89: 257-260.
  • 36. Kavanagh AM, Broom DH. Women's understanding of abnormal cervical smear test results: a qualitative interview study. BMJ 1997; 314: 1388-1391.
  • 37. Campion MJ, Brown JR, McCance DJ, et al. Psychosexual trauma of an abnormal cervical smear. Br J Obstet Gynaecol 1988; 95: 175-181.
  • 38. O'Shea v Sullivan (1994) Aust Torts Rep ¶81-273 (SCNSW).


remove_circle_outline Delete Author
add_circle_outline Add Author

Do you have any competing interests to declare? *

I/we agree to assign copyright to the Medical Journal of Australia and agree to the Conditions of publication *
I/we agree to the Terms of use of the Medical Journal of Australia *
Email me when people comment on this article

Online responses are no longer available. Please refer to our instructions for authors page for more information.