Six years' audit of laboratory workload and rates of referral for colposcopy in a cervical screening programme in three districts.

OBJECTIVE--To determine laboratory workload and rates of referral for colposcopy in a three district cervical screening programme during 1983-9 to assess the feasibility of accommodating call up of all women at risk, recall at three year intervals (now five year intervals), and investigation of women with all degrees of abnormality. DESIGN--Analysis of computerised screening histories dating back to 1977 of women screened in the Avon cervical screening programme. SETTING--Three district health authorities covering the population of Bristol and Weston-super-Mare, comprising 800,000 people, of whom 250,000 were female residents aged 20 to 64. SUBJECTS--196,977 Women aged 20 to 64 screened in cervical screening programme since 1983. RESULTS--Laboratory workload devoted to follow up of women with abnormalities increased sharply between 1987-8 and 1988-9, with increases of 54% (from 2075 to 3196) in the number of smears for follow up of severe dyskaryosis and invasive cancer, 40% (from 1925 to 2695) for mild and moderate dyskaryosis, and 49% (from 1793 to 2677) for borderline change. The increases were partly explained by the introduction in April 1988 of protocols for follow up and investigation based on guidance in an intercollegiate working party report. The proportion of women with mild and moderate dyskaryosis who were recommended for referral for colposcopy increased steadily from 9.9% in 1983-4 to 79.9% in 1988-9, and for borderline change the proportions were 3.5% and 13.6% respectively. Of all women tested in 1988-9, referral for colposcopy was recommended in 3%. CONCLUSIONS--The increase in laboratory follow up work identified, if it continued, could result in half of existing laboratory capacity in Avon being devoted to follow up work by 1993, with little prospect of maintaining call, recall, and quality control. Investigation of all women with minor cytological abnormalities is neither justifiable nor sustainable and will undermine the benefits of screening by increasing the rate of false positive results and the financial costs.     

Cervical screening in Perth and Kinross since introduction of the new contract.

OBJECTIVE--To determine changes in the cervical screening service since the introduction of the new general practitioner contract on 1 April 1990. DESIGN--Analysis of computerised records of cervical screening both before and after introduction of the new contract. SETTING--General practices in Perth and Kinross Unit, Tayside. PATIENTS--A total of 30,071 women aged 21-60 on 26 general practitioner partnership lists. MAIN OUTCOME MEASURES--Percentage average of target population for cervical screening in each practice for first three quarters on introduction of the contract. RESULTS--Perth and Kinross Unit completed a computerised cervical screening call programme in July 1989, which produced an increase from 71% to 78% in the mean percentage of women aged 20-60 who had had cervical smear tests within 5.5 years. Six months after the introduction of the new general practitioner contract the mean population coverage was increased to 85% in women aged 21-60 and only four practices had not attained the 80% upper target compared with 10 on 1 April 1990. Detailed examination of randomly selected practices immediately before the new contract was introduced showed an average artificial list inflation of 4.3% in health board records when compared with practice records, a hysterectomy rate of 6.2%, and an additional 3% of women who were considered to be ineligible for smear testing due to putative virginity or illness or infirmity, or both. There was a considerable shift away from use of well woman clinics (2.7% of smears in 1990 compared with 5.6% in 1988) for taking cervical smears, potentially threatening the long term viability of the clinics. CONCLUSION--The introduction of the new contract for general practitioners has brought about a further sustained increase in population coverage for cervical screening in a small Scottish unit with a stable population, well motivated general practitioners, and a fully integrated computerised call and recall system based on the community health index. To optimise the screening service revision of the targets levels is necessary.     

Evaluation of the cervical cytology screening programme in an inner city health district.

District health authorities have been instructed to operate a cervical cytology call and recall screening programme using the age-sex registers held by family practitioner committees. A detailed evaluation of implementation in an inner London district showed that 477 out of 687 (69%) invitation letters sent to women by the family practitioner committee were either inaccurate or inappropriate: almost half of the recorded addresses were incorrect and a further fifth of the women were not eligible for a test. Overall, 90 women had a smear, which is only 13% of the total but 43% of those found to be eligible. The findings did not differ significantly with age. The findings have major implications not only for the effectiveness of call and recall for screening for cervical cancer but also for the future development of screening for breast cancer in such areas.     

How complete can cervical screening be? The outcome of a call screening programme for women aged 20–60 years in Perth and Kinross

In this paper a computer system for cervical screening call and recall based on the Community Health Index (CHI) population data-base is described. It allows the unscreened population to be identified and located on an individual general practice basis. The results of the call programme on 9517 women aged 20-60 years listed on the CHI and with no record of a cervical smear is described. There was a 24% smear uptake in the call programme which meant that after the call programme the total population cover had risen from 71% to 78%. In addition, if women with a valid reason are excluded, and the data-base corrected for women no longer in the area, the true cover rises to 88%. An analysis of the percentage cover in each GP practice is described with the implications for implementation of screening targets for primary care.     

Preliminary results of a district call scheme for cervical screening organised in general practice.

A recognised problem with the cervical screening programme in the United Kingdom is the failure to include women who have never had a cervical smear test, who are a high risk group. The implementation of a district based call scheme in East Berkshire in 1986 is described whereby women aged 20-64 with no record of a cervical smear test who were judged to be eligible for testing by their general practitioner were sent a personal invitation from their general practitioner to attend for a test. A list of high risk unscreened women was kept by each practice, and a duplicate sent to the cytology laboratory to update the central records. Six months after each batch of invitations had been sent the resulting number of women having a smear test was assessed. Forty three of 51 practices approached agreed to participate in the five year scheme. During the first year lists were sent to the 43 participating practices. The first list was returned to the cytology laboratory by 37 practices and the second by 33; practices varied in their responses, however, some needing considerable persuasion to return the lists. Of 972 identified unscreened women from the total 3757 women listed in the lists of the family practitioner committee, 247 (25%) had a cervical smear test in response to the invitation, representing an overall increase of 7% in the screened population. The preliminary findings of the five year study have shown that screening can be improved by a systematic call scheme. Coordinated support from the area health authority in health education, monitoring of screening, and feedback of data from the scheme to practices is required to reduce the proportion of unscreened women.     

Prospective randomised controlled trial of methods of call and recall for cervical cytology screening.

OBJECTIVE--To discover whether systematic methods of call and recall are more effective than a non-systematic method and to see which of the two systematic methods was more effective. DESIGN--Prospective randomised controlled trial over a year. SETTING--One group general practice. PATIENTS--416 Women over 35 eligible for a smear test who had never had a cervical smear test or in whom a smear test was overdue (previous test more than five years before). INTERVENTIONS--One group received written invitations to have a smear taken. The second group had their notes tagged so that the doctor would remind them (when they attended for another reason) to have a smear test. No special intervention was made in the third group. MAIN OUTCOME MEASURE--Performance of a cervical smear test during the year of the study. RESULTS--32% (45/140) of the screened group, 27% (39/142) of the tagged group, and 15% (20/134) of the control group had a smear test during the year. The percentage of women having a smear test in the screened group was not significantly different from that in the tagged group, but the percentages in the two groups were significantly different from that in the control group. Whether a woman had had a previous smear test significantly affected the uptake of the invitation to have a smear test independently of the method of invitation. CONCLUSIONS--The systematic methods of call and recall were more effective than a non-systematic method. There was no significant difference between the two systematic methods (sending letters or tagging the notes) at one year.     

Cervical screening: how often should women be screened?

Introduction
As a result of major improvements that have been made to cervical screening during the last 15 years, and implementation of call and recall to invite all women aged 20–64 for screening, the incidence of cervical carcinoma has fallen by 42% since 1990¹. Cervical cancer is now a rare disease, largely thanks to the widespread uptake of screening by the women at risk. Despite the manifest success of the NHS Cervical Screening Programme (NHSCSP), there is pressure on one hand to improve its sensitivity by the introduction of new technology, including human papillomavirus (HPV) testing², and on the other hand to reduce the cost of the programme, which is more than £130m per year. The main method suggested to reduce costs is the restriction of routine screening to an interval of 5 years^3–5.     

Costs and benefits of cervical screening. III. Cost/benefit analysis of a call of previously unscreened women

A population‐based cervical screening programme issued invitations to women with no record of a previous smear. This call was very good value, at £5780 per life saved or £159 per life‐year saved at 1991 prices. The first priority for the cervical screening service should be comprehensive coverage.     

Evaluation of a call programme for cervical cytology screening in women aged 50-60.

For many years Tayside has benefited from a successful opportunistic cytology screening programme. In recent years, however, the decrease in mortality due to cervical cancer has levelled off, with most cases of severe disease arising in women who have not been screened. In view of this the health board developed a new computer system for call and recall based on the community health index. This facility allowed the unscreened population to be identified and located on an individual general practice basis. The findings of the call programme in the 3136 women aged 50-60 were studied. The 29 practices in Perth and Kinross participated in the scheme. Before the call started 4287 out of 7423 (58%) women had been screened, and after the call programme this had risen to 5109 (69%). Moreover, a further 1158 (15%) women were identified who had a valid reason for exclusion from the programme. This meant that 6267 (84%) women of the study population were accounted for by the system. The call programme in Tayside will be completed in 1989 and will include all women aged 20-60.     

The use of screening episodes linked to CIN3 and invasive cancer registrations to study outcomes from the NHS Cervical Screening Programme

Objective: To examine how NHS cervical screening data can be collected and analysed in order to evaluate women’s screening histories as episodes rather than as individual smears. Design: Analysis of routine cervical screening data grouped into screening episodes for a cohort of women regarding episodes starting in a given year. Setting: NHS Cervical Screening Programme. Population: Data from four Health Authorities (now eight Primary Care Trusts) from the NHS Cervical Screening Programme with primary smears (first in an episode) taken between 1 April 1999 and 31 March 2000. Methods: Cytology information obtained from the call/recall (‘Exeter’) computer system was linked to cervical intraepithelial neoplasia (CIN) 3 and invasive cancer outcome information obtained from cancer registries. Screening histories were divided into episodes, each starting with a primary smear that was followed up to episode closure or, for episodes still open followed for an average 4.25 years, from the primary smear. The episode was divided into two parts (up to referral to colposcopy and following the referral). The outcomes of the episodes are described including referral rate to colposcopy and CIN3 and invasive cancer rates by factors such as age. Main outcome measures: Episode histories and rates of referral to colposcopy, CIN3 and invasive cancer. Results: There were 176 923 episodes from 176 319 women (1.003 episodes per woman) followed up to March 2004, the date at which the first phase of information accrual ceased. Of these episodes, 172 100 (97.3%) were closed either by a negative smear referring the woman back to routine recall or by default (defined as no smear recorded within 21 months following a smear requiring an action of repeat or refer to colposcopy). The remaining 4823 (2.7%) of episodes were still open, of which in 3121 (1.8%) the woman had been referred to colposcopy and in 1702 (1.0%) no referral decision had been made. Referral rates to colposcopy varied by age from 5.7% in women aged 20–24 years down to 0.9% in women aged 60–64 years. The overall efficiency of screening was highest for woman aged about 30 years, with a CIN3 detection rate of eight per 1000 women and a positive predictive value (for CIN3 or worse) of referral to colposcopy of 21%. Conclusion: The study has shown that routinely collected NHS cervical screening data can be combined to give information on complete episodes, allowing important performance measures to be studied. We suggest that in future information in the NHS screening system should be structured to facilitate such analysis and to allow cytology and histology information to be readily linked.     

Cervical cytology screening and government policy.

OBJECTIVE--To assess the coverage of cervical cytology screening in one general practice surgery according to the criteria in the new Scottish general practitioner contract and to explore the difficulties of defining performance in such screening. DESIGN--Review of annual analysis of uptake of screening during 1984-8. SETTING--Suburban general practice surgery in Glasgow serving 3000 patients. PATIENTS--All women aged 35-64 registered in 1984 increasing in 1988 to all women aged 20-64. MAIN OUTCOME MEASURE--Assessment of uptake of smear tests and reasons for smear not being taken and of the effect of these outcomes on the new general practitioner contract. RESULTS--The numbers and percentages of women having a smear test in the previous five and three years were recorded, and the reasons why a smear was not taken were defined in the remainder (hysterectomy, test not offered, risk not known, test declined, patient moved away, and patient unaccounted for). In 1988, 85% (608/719) of the women aged 30-64 and 80% (693/870) of those aged 20-64 had had a smear test in the previous five years. An appropriate or irreducible reason for the lack of a smear test was defined in all the others. CONCLUSIONS--The population studied contained a substantial number of women in whom cervical smear was unnecessary, inappropriate, or refused. These factors and the likely demographic variation in the uptake of smear tests have important implications for the setting and achieving of the government''s targets for cervical cytology screening.     

Adherence to recommendations for early repeat cervical smear tests.

OBJECTIVE--To assess adherence to recommendations for an early repeat cervical smear test in women with reports of cytological abnormalities, and to evaluate the impact of reminder letters to medical practitioners when such smear tests are overdue. DESIGN--Observational study. SETTING--Cytology (gynaecological) service for Victoria, Australia. SUBJECTS--Two groups of women who had abnormal cervical smears during 1985. Women in group A had some evidence of an important dysplasia and were advised to have a repeat smear in three months'' time whereas women in group B had a less serious abnormality and were advised to have a repeat smear test in six months'' time. In all, 971 of the 1036 women in group A and 1401 of the 1464 women in group B were eligible to have a repeat smear analysed by the service. INTERVENTION--If a repeat smear had not been received within three months of the recommended date a reminder letter generated by the service''s computer was sent to the medical practitioner who had taken the smear. END POINT--Thirty six months after the report on the abnormal smear was issued. MEASUREMENTS AND MAIN RESULTS--In all, 870 (90%) of the women in group A and 1154 (82%) of the women in group B had a repeat smear test. The mean time to a repeat test was 3.0 months (95% confidence interval 0.5 to 16.4) in group A and 6.0 months (1.2 to 30.3) in group B. The reminder letter to the practitioner potentially increased the rate of return for a repeat smear test by 18% in group A and 24% in group B. Adherence to the recommendation for a repeat test increased with increasing age. CONCLUSIONS--Achieving high rates of follow up smear tests and appropriate management in women with cytological abnormalities is critical to the impact of a screening programme for cervical cancer. The reminder system used in this study was not labour intensive or expensive and provided a fail safe mechanism for ensuring that reports of abnormal smears were not overlooked.     

Predicting mortality from cervical cancer after negative smear test results.

OBJECTIVE--To assess the relative protection against death from cervical cancer after two or more negative smear test results and compare it with the protection against invasive cancer estimated by an International Agency for Research on Cancer (IARC) working group in an analysis of data from 10 large screening programmes. DESIGN--Comparison of risk of death from cervical cancer after two or more negative smear results with the risk in unscreened women by using a model constructed with data from the British Columbia screening programme. MAIN OUTCOME MEASURES--Mortality from and incidence of invasive cancer. RESULTS--In women with two negative smear results estimates of protection against cervical cancer were about 50% higher when lethal invasive cancer was used as the criterion rather than all invasive cancer. This difference was due to these women being more likely to attend for further tests at which invasive cancer could be detected: screen detected cancer has a better prognosis than clinically diagnosed cancer. Screening intervals could be longer than three years: screening women aged 35-64 every five years was predicted to result in a 90% reduction in mortality from cervical cancer. CONCLUSION--Because protection from mortality is higher than protection from disease and because of the high costs and negative side effects of frequent screening, screening intervals should be longer than three years.     

Cervical screening in an inner city area: response to a call system in general practice.

To determine whether a cervical screening call system based in general practice in a deprived inner city area would increase the numbers of women who came forward for cervical smears the response to letters of invitation for screening was monitored for one year in one general practice in the Paddington and North Kensington district of London. Women aged 20-64 were identified from the computerised age-sex register. Only 16% of these women had had a smear test. A total of 750 call letters was sent out. Initially the response was poor (57 women; 22%), and 85 (32%) letters were returned marked "address unknown." After the age-sex register was updated the response to call was 330 women (44%). The response of women aged over 35 was better than the response of women aged 35 and under (229 (53%) v 101 (32%)). In the year of the study the number of women aged 20-64 on the revised register who had been screened rose by 330 (14%). A general practice based call system can improve uptake of cervical screening even in a highly mobile, socially underprivileged population.     

How district health authorities organise cervical screening.

OBJECTIVES--To examine how district health authorities organised cervical screening with respect to Department of Health guidelines and to determine their assessment of the problems encountered. DESIGN--Postal questionnaire sent to all 190 district health authorities in England in 1989. PARTICIPANTS--190 District health authorities in England. MAIN OUTCOME MEASURES--Population coverage of screening, quality of smear testing, and follow up of abdominal test results in comparison with national guidelines for district cervical screening services, and problems encountered by districts. RESULTS--Replies were received from 178 (94%) of districts, in 143 of which the person named as responsible for cervical screening contributed. All districts implemented a computer managed scheme, 150 by the target date of 31 March 1988, but not all of these conformed with the guidelines. At the time of the survey only just over half called women in the target age group of 20-64 and only 70% expected to meet the target date of 13 March 1993 for completing the call. Considerable variation was evident among the schemes with regard to how they dealt with issues related to population coverage, quality of testing, and follow up of abnormal results. The problems most commonly identified by the districts (n = 174) were laboratory workload (107, 61%), computer software (104, 60%), availability of resources (78, 45%), non-attendance (77, 44%), rate of opportunistic screening (62, 36%), and investigation and treatment (60, 34%). CONCLUSIONS--Current practice in running cervical screening schemes needs to be examined to determine the extent to which it contributes to the goal of reducing mortality from cervical cancer.     

Audit of practice based cervical smear programme: completion of the cycle.

OBJECTIVES--To determine the effectiveness of a practice based cervical screening programme and the changing pattern of abnormal smear results and to improve the quality of care provided for patients. DESIGN--Audit of practice held data on cervical screening from 1980 to 1990. Changes in the programme were made after analysis of first five years'' data. SETTING--Mixed urban and rural practice of 10,900 patients in Northumberland. SUBJECTS--Women aged 20-65 who had not had a hysterectomy. RESULTS--2356 (85.1%) of the 2767 targeted women had a test during 1980-5 and 2498 (89.5%) of the 2790 women had a test during 1985-90. Inviting women aged 20-25 to attend for a test increased coverage from 45.8% (146/319) in 1980-5 to 82.5% (282/342) in 1985-90. The proportion of women with abnormalities requiring hospital referral rose in the second half of the study, especially among younger women (from 17/39 (44%) to 45/64 (70%) in women aged 25-34). CONCLUSIONS--Practice based cervical screening programmes can be highly effective. Cytological abnormalities affect patients psychologically as well as physically and practices should provide support and explanation for patients with abnormal results. Data from individual practices should be aggregated to allow health authorities to plan secondary care effectively.     

Long term follow up of women with borderline cervical smear test results: effects of age and viral infection on progression to high grade dyskaryosis.

OBJECTIVE--To follow up and assess the significance of borderline change in cervical smears. DESIGN--Retrospective study of women undergoing routine cervical cytological screening in 1981. SETTING--Avon Cervical Screening Programme, covering 250,000 women in Bristol and Weston super Mare. SUBJECTS--437 women showing borderline cervical changes in 1981 and 437 age matched controls with normal results in 1981. MAIN OUTCOME MEASURES--Cytological progression to high grade dyskaryosis (cervical intraepithelial neoplasia grade III or invasive carcinoma). RESULTS--During follow up ranging from 13 to 106 months 98 of the 437 women (22.4%) with borderline cytological changes on routine cervical cytology screening had a subsequent smear test showing high grade dyskaryosis compared with three of the 437 women (0.9%) in the control group. The risk of progression was greater in women aged 20 to 39 than in those aged 40 and over. Human papillomavirus infection had initially been diagnosed cytologically in 101 of the 437 (23%) women with borderline results. Significantly fewer of these women developed high grade dyskaryosis (13/98 (13%) v 88/339 (26%), p less than 0.05). CONCLUSIONS--Women with borderline smear test results are at increased risk of developing high grade dyskaryosis, particularly if the borderline changes occur without cytological features of human papillomavirus infection. Progression occurs within three years in 50% of cases, although a linearly increasing risk was sustained over the nine years of follow up and was greatest in women aged 20 to 39. Careful follow up of these women is indicated.     

Cervical cytology in the Vale of Trent faculty of the Royal College of General Practitioners, 1985-8.

OBJECTIVE--To assess changes in the organisation and performance of cervical cytology programmes in the practices of members of the Vale of Trent faculty of the Royal College of General Practitioners. DESIGN--Retrospective audits completed in 1985 and 1988 by general practitioners on a sequential sample of 100 records of women aged 35-64 in their practice. SETTING--General practices in which one or more partners were members or associates of the Vale of Trent faculty of the college, of which 76 participated in the first audit and 55 (82% of 67 eligible practices) in the second. SUBJECTS--Sequential samples of 100 women born between 1 January 1920 and 31 December 1949 (first audit) and between 1 January 1923 and 31 December 1952 (second audit) whose surnames began with P or B respectively. MAIN OUTCOME MEASURES--Percentage of women in each practice with a record of cervical cytology performed in the previous five years and percentage with no recorded smear. RESULTS--Of the 76 practices completing the audit in 1985, 55 (82% of those eligible) repeated the exercise in 1988. Performance was not significantly different in practices that did and did not respond. The median percentage of women who had had a smear in the previous five years was 49% and 69% in 1985 and 1988 respectively (p less than 0.001) and that of women with no record of a cervical smear was 28% and 16% respectively (p less than 0.001). All but six practices showed improvement in both outcome measures. In both audits an active call system was associated with a significantly increased performance (p less than 0.05). In nine practices (16%) 80% or more of the samples of women had had a smear in the previous five years. CONCLUSION--Organisation and performance of practices audited improved between 1985 and 1988. Although this might result from participation in the first audit, it probably represents a more general trend within primary care. ACTION--Between the two audits more practices (87% v 67%) had developed a policy on screening, and this was more likely to include the aim of performing regular smears on all sexually active women (98% v 80%).     

Screening and self examination for breast cancer.

Breast cancer is the major form of cancer in women, with nearly 30,000 new cases and over 15,000 deaths in the United Kingdom each year. Breast screening by mammography has been shown in randomised trials to reduce mortality from breast cancer in women aged 50 and over. An NHS breast screening programme has been in operation in the United Kingdom since 1988. Its aim is to reduce mortality from breast cancer by 25% in the population of women invited to be screened. The uptake of mammography among the eligible population may be the single most important determinant if the programme is to be effective. Primary care teams have an important part to play in encouraging women to attend for screening and in providing information, advice, and reassurance at all stages of the screening process. To date, routine breast self examination has not been shown to be an effective method of screening for breast cancer and should not therefore be promoted as a primary screening procedure. There is, however, a case to be made for women to become more "breast aware."     

Screening for squamous cervical cancer: duration of low risk after negative results of cervical cytology and its implication for screening policies. IARC Working Group on evaluation of cervical cancer screening programmes.

A collaborative study of screening programmes in eight countries was performed to estimate the risks of cervical cancer associated with different screening policies. Most of the data came from centrally organised screening programmes. Relative protection was higher in women who had had two or more negative results of screening tests than in those who had had only one negative smear, particularly in the first five years after the last test. There was little difference in the protection afforded by screening every year compared with every three years, but screening only once every five or 10 years offered appreciably less protection. The age of the women did not affect the sensitivity of the test or the sojourn time of the disease (the length of the detectable preclinical phase during which abnormal cytology could be picked up if a smear were taken); invasive cancer in women under 25 was rare. Centrally organised screening programmes were more effective than uncoordinated screening. Screening programmes should be aimed principally at women aged 35-60 but should start some years before the age of 35, and the intervals between screening should be three years or less.