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PubMed2006

Patient-physician colorectal cancer screening discussions and screening use.

BACKGROUND: Little is known about patient-physician colorectal cancer (CRC) screening discussions or how discussion content affects screening use. Analyses conducted in 2004-2005 of patient-physician CRC screening discussion content and its association with screening use are described. METHODS: A mailed survey and retrospective claims data were used to compile information on insured, primary care patients aged 50 to 70 years (n = 4966). The survey collected information on patient-physician CRC screening discussion content (including the 5A's: assess, advise, agree, assist, and arrange). Survey responses were linked with 5-year retrospective claims data (ending December 31, 2003) on CRC screening use. Among patients reporting screening discussions, generalized estimating equation approaches were used to estimate the association of discussion content with screening use. RESULTS: Among those reporting discussion information (n = 2463), 80% reported discussing CRC screening with their physician. The content of these discussions varied, and only 54% used CRC screening. Multivariable model results indicated that the likelihood of screening was greater among patients reporting help scheduling an appointment (assist) (odds ratio [OR] = 2.69, 95% confidence interval [CI] = 1.95-3.72) and those reporting a discussion of results or follow-up (arrange) (OR = 1.63, 95% CI = 1.18-2.24), and lower among patients offered a choice among screening modalities (agree) (OR = 0.57, 95% CI = 0.37-0.86) as well as among those who wanted more screening information (OR = 0.65, 95% CI = 0.43-0.97). CONCLUSIONS: Not all patient-physician CRC screening discussions result in CRC screening use. It is important to understand which aspects of shared decision making and discussion content are likely to increase informed and value-concordant decisions to participate in recommended evidence-based CRC screening.

Aged↗

PubMedDate not supplied

Determinants of cancer screening frequency: the example of screening for cervical cancer.

BACKGROUND: Cancer screening frequency should be based on the rate of progression of the disease and the sensitivity of the screening test. A common misconception is that a person's risk of getting the disease determines how often they should be screened. METHODS: We describe algebraically the theoretical interaction of disease progression rate and screening test sensitivity determining the portion of invasive cancers prevented by screening. After discussing the assumptions and limitations of the model, we apply this model to the example of screening for cervical cancer. Actual data from large screening programs assembled by the International Agency for Research on Cancer (IARC) are used to test the assumptions of the model. RESULTS: A simple formula can express the relation between disease progression rate, sensitivity of the screening test, screening frequency, and screening error. Disease prevalence does not figure in this equation. The IARC data suggest that, at least for cervical cancer, as screening frequency increases, incremental sensitivity of the test decreases or remaining undetected cases progress more rapidly so that anticipated benefits from more frequent screening are not realized. CONCLUSIONS: Rate of disease progression and sensitivity of the screening test are the proper determinants of cancer screening frequency. Because these factors can vary depending on screening frequency, however, the optimal screening interval for a particular cancer must be determined by clinical trials.

Data Interpretation, Statistical↗

PubMed2004

A comparison of the impact of screen-positive results obtained from ultrasound and biochemical screening for Down syndrome in the first trimester: a pilot study.

OBJECTIVE: To compare the experiences of women who received a screen-positive test result for Down syndrome after nuchal translucency screening or after biochemical screening in the first trimester of pregnancy in the Netherlands. METHOD: Semi-quantitative questionnaires were sent to 40 women with a screen-positive test result for Down syndrome in the first trimester of pregnancy: 20 had undergone nuchal translucency screening (NT group) and 20 had undergone serum screening (PAPP-A and free beta-hCG) (SS group). In all the cases, chorionic villus sampling (CVS) had not revealed any chromosomal abnormalities. RESULTS: The major reason for undergoing the screening test in both groups of women was to be more reassured about the health of the baby. In the NT group, 5 out of the 20 women stated that they had suddenly been confronted with the NT measurement during the ultrasound examination without even being asked, or had been caught by surprise about the possibility. Together with two other women, they felt that at that stage they had been insufficiently informed about what the test meant. In the SS group, two women also held this opinion. In 10 out of the 20 women in the SS group, the positive-screening result had caused (a great deal of) anxiety. In the NT group, this proportion was as high as 18 out of the 20. Six of the women in the NT group mentioned that 'seeing the baby' had been an important factor in their decision to undergo CVS. Even after a favourable result of CVS, a proportion of the pregnant women were still feeling anxious about the health of their baby (5 women in the SS group and 12 in the NT group). Nevertheless, a large proportion of the women in both groups was pleased that they had undergone the screening test. Only a few of them stated that they would not choose the same screening test again in a future pregnancy. CONCLUSIONS: An unfavourable screening result after NT screening appeared to have a greater impact than an unfavourable result after serum screening. This might partly be explained by the ultrasound examination visualising the increased risk during NT screening. An additional important role may have been played by the fact that an abnormal NT screening result implies an increased risk of other disorders besides Down syndrome, which the women should be informed about beforehand. Several factors place special demands on the counselling prior to NT screening.

Adult↗

PubMed2025

The acceptability of blood spot screening and genome sequencing in newborn screening: a systematic review examining evidence and frameworks.

BACKGROUND: Population-wide newborn blood spot screening programmes are a successful public health intervention used to detect whether the baby is at risk of certain rare conditions, with the aim of earlier diagnosis and provision of optimal care and treatment. Evaluating candidate conditions to include in newborn blood spot and genetic sequencing raises questions regarding acceptability to parents/carers. METHODS: In the context of the possible expansion of the newborn blood spot screening programme in the United Kingdom, this review aimed to systematically review research on the acceptability to parents of newborn blood spot screening and genetic sequencing. A protocol was developed prior to commencing the review and was registered on the PROSPERO database. A team of researchers carried out the review, with checking at all stages carried out by at least two individuals. We included research published after 2013 with participants who were pregnant or a recent parent of a newborn and were resident in a high-income country. We included quantitative and qualitative studies that investigated the acceptability to parents/carers of newborn blood spot screening or genetic sequencing. Quantitative studies were narratively synthesised, and theories/frameworks identified and evaluated. Qualitative studies were analysed for recurring themes, and a meta-synthesis was carried out to compare and contrast these two types of data. We quality appraised included articles using tools appropriate for their study design. RESULTS: Searches were carried out in September to November 2023 and screening identified 25 relevant research articles. Just over half were from North America, with four existing reviews and nine qualitative studies. Domains of acceptability described in the literature were: support for screening; level of anxiety, information and knowledge; consent; views of the procedure; and support after screening. The research indicated consensus support for blood spot screening, and for expanding to some other conditions, although some parental anxiety was reported. Parents/carers mostly perceived that they had received sufficient information, but the timing of this could be improved. While parents indicated interest in genomic screening, studies highlighted the need for clearer consent procedures and greater support for parents following genomic screening than for blood spot screening. Only three included studies reported using any kind of theoretical framework. DISCUSSION: Most parents/carers found newborn blood spot screening programmes to be acceptable and favoured their large-scale implementation. A minority of parents/carers expressed concerns regarding the acceptability of processes underpinning newborn blood spot screening, such as consent, the timing of receiving information and support available after testing. More research is needed regarding the acceptability of newborn genomic sequencing screening programmes, which are less established compared with newborn blood spot screening programmes. LIMITATIONS: The over-representation of studies conducted in the United States has implications for the applicability of findings to other countries where testing is not typically mandatory and health systems differ considerably. Most studies were of cross-sectional design and there was limited representation of people from lower incomes and non-white ethnicity. While the inclusion of studies only in populations of future or very recent parents provided coherence to the findings, unclear reporting of participants may have resulted in under- or overinclusion of some studies. FUNDING: This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number NIHR159927.

ACCEPTABILITY↗

PubMed2006

Factors associated with return for routine annual screening in an ovarian cancer screening program.

OBJECTIVE: To identify clinical, demographic, dispositional, and attitudinal variables associated with return for routine, annual transvaginal sonography (TVS) screening for ovarian cancer. METHODS: Asymptomatic, average to high risk, women (n=585) participating in a free university-based ovarian cancer screening program completed a baseline interview prior to undergoing an initial TVS screening test. During the baseline interview, demographic (age, education, partner status, race), clinical (family history of ovarian cancer), dispositional (optimism, health values), and attitudinal (perceptions of personal risk for ovarian cancer and effectiveness of screening, intentions to return for repeat routine screening, discomfort during screening, satisfaction with the screening process, ovarian cancer-specific distress) information was obtained. Return for repeat screening was documented from screening program records. RESULTS: Results from both multivariate proportional hazards and logistic regression analyses indicated that stated intentions to return for a repeat screening test within the next year was the strongest predictor of return for repeat screening. Possessing > or =12 years of education was also associated with a greater likelihood of repeat screening in both the proportional hazards and logistic regression analyses. CONCLUSIONS: Results provide further support for low education as a risk factor for suboptimal participation in cancer screening. Results also highlight the critical link between intentions to perform a health-protective behavior and subsequent performance of that behavior and suggest that repeat screening could be enhanced by eliciting both an intention to return for annual ovarian cancer screening as well as a specific plan for implementing this intention.

Adult↗

PubMed1994

Age-specific effectiveness of the Nijmegen population-based breast cancer-screening program: assessment of early indicators of screening effectiveness.

BACKGROUND: The benefits of mammographic screening for breast cancer are not clear for women less than 50 years old. PURPOSE: Our aim was to evaluate the effectiveness of breast cancer screening in different age groups. METHODS: A mammographic breast cancer-screening program with a 2-year screening interval has been under way in Nijmegen, The Netherlands, since 1975. After eight rounds, more than 40,000 women have been invited to participate. All breast cancer cases diagnosed in the invited population, whether detected by screening or clinically, have been considered in this study. The age groups are younger than 50 years, 50-69 years, and 70 years or older at last invitation before diagnosis. Our assessment of the effectiveness of screening is based on the proportion of screen-detected cancers among all cancers and on the disease stage at diagnosis. RESULTS: For women younger than 50, compliance was 75%, and 37% (85/230) of the cancers were detected by screening. The age group 50-69 years had a compliance of 65% with 48% (288/595) of cancers detected by screening, and the group 70 years or older had a 25% compliance with 35% (108/305) of cancers detected by screening. The sizes of the cancers detected by screening were smaller than those detected clinically for all age groups. The age group under 50 showed no substantial difference in the proportion of positive axillary lymph node status between screening-detected and clinically diagnosed cancers, while among older women, the proportion of lymph node involvement was substantially higher for clinically detected cases. A significantly lower frequency of advanced stages was observed in screen-detected compared with clinically diagnosed cancers for women 50 years of age or older (P < .001) but not in women under 50 (P = .35). CONCLUSIONS: No positive effect of the biennial screening program is apparent for women under age 50. For women aged 50 and above, the screen-detected cancers have a more favorable stage distribution than clinically diagnosed cancers, a prerequisite for a reduction in breast cancer mortality.

Adult↗

PubMed1999

Evaluation of a selective screening for colorectal carcinoma: the Taiwan Multicenter Cancer Screening (TAMCAS) project.

BACKGROUND: Although the efficacy of mass screening for colorectal carcinoma (CRC) with a fecal occult blood test has been demonstrated in several randomized trials, a mass screening approach used in countries with intermediate or low incidence of CRC might be costly. Screening high risk people may be an alternative approach, to aid in the prevention of death from CRC. However, the efficacy of CRC screening for high risk people in such countries is uncertain. METHODS: For this study, a multicenter design was devised to identify high risk groups without clinical symptoms related to CRC; these subjects were identified through the study of index cases of CRC in Taiwan. Colonoscopy, in combination with a fecal occult blood test or double-contrast barium enema, was used to screen high risk groups. A total of 8909 subjects were invited to attend screening. Of 8909, 81 with asymptomatic CRC were detected in one-shot screening. Markov models, in conjunction with a simulated approach, were proposed to estimate relevant parameters in relation to disease progression and to assess the effect of the interval between screenings on the efficacy of CRC screening for these high risk groups. RESULTS: The estimated preclinical incidence rate was 0. 00396 (95% confidence interval [CI], 0.002944-0.004985), which was 21 times that reported from a cancer registry in 1994. The simultaneous estimations of mean sojourn time (the average duration between the preclinical screen-detectable phase and the clinical phase) and sensitivity were 2.8 years (95% CI, 2.15-4.30) and 95.0% (95% CI, 24.4-99.9%), respectively. Predictions of mortality reduction for people who received annual, biennial, and triennial screening regimes compared with controls were 26% (95% CI, 0-50%), 23% (95% CI, 0-48%), and 21% (95% CI, 0-47%), respectively. CONCLUSIONS: The efficacy of selective colorectal carcinoma screening has been demonstrated in this study. A high preclinical CRC incidence rate also suggests that such a screening strategy might be cost-effective for countries with intermediate or low incidence of CRC. Methods proposed in this study can be used to evaluate the efficacy of CRC screening in similar screening trials.

Colonoscopy↗

PubMed1997

What is a screening test? Misclassification bias in observational studies of screening for cancer.

OBJECTIVE: To demonstrate the importance of accurately identifying clinical distinctions of subjects in observational studies of screening. DESIGN: Simulated case-control studies. SETTING: The West Haven Veterans Affairs Medical Center. PATIENTS: Fifty-two men diagnosed with prostate cancer in 1988 or 1989 had 252 digital rectal examinations (DREs) in the preceding 5 years. A classification scheme used patient symptoms and the results of prior DREs to assign the last DRE before the diagnosis of cancer to one of the following categories: definite screening, likely screening, probable screening, not screening, or other and unknown. Sixty-five percent of the DREs were classified as definite or likely screening, and another 15% were classified as probable screening. MAIN RESULTS: Changing the definition of a screening DRE from one including to one excluding probable DREs lowered the frequency of screening in case subjects more than it did in case controls, and thus lowered the odds ratio (OR), making screening appear to be more protective. Even when DRE was not protective, the ORs for the effectiveness of screening with the more restrictive definition ranged from 0.21 to 0.83 in 36 simulated case-control studies that differed according to the frequency of screening, the prevalence of cancer in case controls, and the extent of misclassification error. CONCLUSIONS: If clinical distinctions in the performance of screening tests are not classified appropriately, observational studies will misrepresent the proportion of subjects exposed to screening interventions and produce biased results.

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PubMed2002

Cost-effectiveness of cervical cancer screening: comparison of screening policies.

BACKGROUND: Recommended screening policies for cervical cancer differ widely among countries with respect to targeted age range, screening interval, and total number of scheduled screening examinations (i.e., Pap smears). We compared the efficiency of cervical cancer-screening programs by performing a cost-effectiveness analysis of cervical cancer-screening policies from high-income countries. METHODS: We used the microsimulation screening analysis (MISCAN) program to model and determine the costs and effects of almost 500 screening policies, some fictitious and some actual (i.e., recommended by national guidelines). The costs (in U.S. dollars) and effects (in years of life gained) were compared for each policy to identify the most efficient policies. RESULTS: There were 15 efficient screening policies (i.e., no alternative policy exists that results in more life-years gained for lower costs). For these policies, which considered two to 40 total scheduled examinations, the age range expanded gradually from 40-52 years to 20-80 years as the screening interval decreased from 12 to 1.5 years. For the efficient policies, the predicted gain in life expectancy ranged from 11.6 to 32.4 days, compared with a gain of 46 days if cervical cancer mortality were eliminated entirely. The average cost-effectiveness ratios increased from $6700 (for the longest screening interval) to $23 900 per life-year gained. For some countries, the recommended screening policies were close to efficient, but the cost-effectiveness could be improved by reducing the number of scheduled examinations, starting them at later ages, or lengthening the screening interval. CONCLUSIONS: The basis for the diversity in the screening policies among high-income countries does not appear to relate to the screening policies' cost-effectiveness ratios, which are highly sensitive to the number of Pap smears offered during a lifetime.

Adult↗

PubMed2002

Using Medicare data to estimate the prevalence of breast cancer screening in older women: comparison of different methods to identify screening mammograms.

OBJECTIVES: To compare different methods for defining screening mammograms with Medicare claims and their impact on estimates of breast cancer screening rates. METHODS: Medicare outpatient facility and physician claims for 61,962 women in 1993 and 59,652 women in 1998 were reviewed for evidence of receipt of screening mammography. We compared the estimates of screening mammography use derived from CPT (Current Procedure Terminology) codes to categorize mammograms as screening or diagnostic versus using an algorithm that uses CPT codes plus breast-related diagnoses in the prior two years. We also compared estimates obtained from review of physician claims alone, facility claims alone, or the combination of the two sources of claims. RESULTS: Use of physician claims alone produced estimates of screening rates similar to rates calculated from use of both physician and outpatient (facility) claims. In 1993, the CPT code for screening mammography underestimated the rate of screening compared to estimates generated by using the algorithm (8.3 percent versus 18.0 percent prevalence, p<0.001). By 1998, the screening prevalence rate generated from using the CPT code for screening mammography more closely approximated the rate generated by the algorithm (23.0 percent versus 25.1 percent). By all methods of estimating screening mammography with Medicare claims, its prevalence increased substantially between 1993 and 1998. CONCLUSION: Providers increased their use of the screening mammography code in their charges to Medicare during the 1990s. This has improved the claims' ability to distinguish screening from diagnostic mammograms, but screening rates computed with claims continue to fall below those generated from self-reports of mammography use among general populations of older women.

Aged↗

PubMed1998

Cost effectiveness of shortening screening interval or extending age range of NHS breast screening programme: computer simulation study.

OBJECTIVE: To compare the cost effectiveness of two possible modifications to the current UK screening programme: shortening the screening interval from three to two years and extending the age of invitation to a final screen from 64 to 69. DESIGN: Computer simulation model which first simulates life histories for women in the absence of a screening programme for breast cancer and then assesses how these life histories would be changed by introducing different screening policies. The model was informed by screening and cost data from the NHS breast screening programme. SETTING: North West region of England. MAIN OUTCOME MEASURES: Numbers of deaths prevented, life years gained, and costs. RESULTS: Compared with the current breast screening programme both modifications would increase the number of deaths prevented and the number of life years saved. The current screening policy costs 2522 pounds per life year gained; extending the age range of the programme would cost 2612 pounds and shortening the interval 2709 pounds per life year gained. The marginal cost per life year gained of extending the age range of the screening programme is 2990 pounds and of shortening the screening interval is 3545 pounds. CONCLUSIONS: If the budget for the NHS breast screening programme were to allow for two more invitations per woman, substantial mortality reductions would follow from extending the age range screened or reducing the screening interval. The difference between the two policies is so small that either could be chosen.

Age Factors↗

PubMed2004

Poorer self assessed health in a prospective study of men with screen detected abdominal aortic aneurysm: a predictor or a consequence of screening outcome?

STUDY OBJECTIVES: To assess the extent to which poorer self assessed health in men in whom an abdominal aortic aneurysm (AAA) is detected at screening is a consequence or a predictor of screening outcome. DESIGN: Prospective study. SETTING: Community based screening. PARTICIPANTS: 23 654 men who attended for AAA screening as part of the UK multicentre aneurysm screening study completed a measure of self assessed health before screening. A total of 1156 had an aneurysm detected. A sub-sample of screened men (571 with an aneurysm and 609 with a normal aorta) also completed the measure of self assessed health six weeks after screening. MAIN RESULTS: Men in whom an aneurysm was detected at screening perceived their health to be poorer before screening than those with a normal aorta. Adjusting for risk factors for AAA made no difference to this RESULT: self assessed health remained a strong predictor of having an aneurysm (odds ratio 1.7 comparing the extreme quartiles of self assessed health, 95% confidence intervals: 1.4 to 2.0). Men with an aneurysm also perceived their health to be poorer after screening had detected their aneurysms, but only to an extent in line with their pre-screening perceptions. CONCLUSIONS: Self assessed health seems to predict having an aortic aneurysm, independently of known risk factors. This emphasises the importance of assessing baseline perceptions of health to prevent erroneously inferring that poorer self assessed health in those who screen positive is a consequence as compared with a predictor of screening outcome.

Aged↗

PubMed2002

[Mammographic screening in the county of Copenhagen. Clinical consequences of the first three screening rounds].

INTRODUCTION: Service mammography has been offered biennially to women aged 50-69 years in the municipality of Copenhagen since 1991. The results were compared to breast cancer cases before initiation of screening. The comparison concerns prognostic factors and the treatment-related consequences. MATERIAL AND METHODS: Data from the Copenhagen service mammography screening were linked to data from the DBCG database. RESULTS: Before screening, 16% of breast cancer cases had a tumour size of 10 mm or less, this percentage increased to 41 in the screen-detected cases. Sixty per cent of breast cancer cases showed no evidence of metastatic spread to axillary lymph nodes before screening; this percentage increased to 78 per cent in the screen-detected cases. Forty per cent of ductal carcinomas showed a malignancy grade I before screening, compared to 53% in the screen-detected cases. Thirteen per cent were treated with breast conserving therapy before screening, as opposed to 48% in the screen-detected cases. Forty-one per cent needed postoperative adjuvant treatment before screening, compared with 21% in the screen-detected cases. DISCUSSION: A marked improvement was seen in the prognostic and treatment-related characteristics of the screen-detected breast cancer cases, as compared to breast cancer cases from the same area before screening was initiated.

Aged↗

PubMed2002

[The pretentions and achievements of cancer screening, in particular breast cancer screening].

The 'Vereniging Nederlands Tijdschrift voor Geneeskunde' (Dutch Journal of Medicine Association) recently held a conference about the doubts expressed in recent publications concerning the value of cancer screening and breast-cancer screening in particular. In this the discussion mainly focused on whether disease-specific mortality or overall mortality should be taken as an endpoint in the evaluation of the screening procedure. In a recent advisory report, the Health Council of the Netherlands stated that the present form of breast cancer screening ought to be continued in the Netherlands for the time being. However, during the conference it was emphasized that cancer screening must be viewed as a highly complex system. Therefore, it is impossible to measure the effects of screening by considering just one end-point, such as cancer-specific mortality. The opinion was also expressed that with the introduction of new forms of cancer screening (e.g. colon or prostate-cancer screening), experience should first of all be gained with the small-scale screening of persons with an elevated risk. This is a task in which the government should lead the way. Furthermore, the government will also need to regulate the enthusiasm that can be expected for various types of secondary preventative diagnostics offered on the free market, including cancer screening. Another important aspect of cancer screening is ensuring that the general public are thoroughly and carefully informed about the pros and cons of cancer screening. The public must know that although cancer screening can save lives, it also causes harm. People scarcely realise that screening may more often involve a loss of carefree years of life than a small chance of living longer.

Breast Neoplasms↗

PubMed2004

Incidence of invasive breast cancer and ductal carcinoma in situ in a screening program by age: should older women continue screening?

OBJECTIVE: The evidence for the effectiveness of screening is strongest for women ages 50 to 69 years; however, there is variation in the target age group for screening programs between different countries. In particular, there is uncertainty over whether women should continue screening once they reach age 70. We therefore investigated incidence rates for invasive and in situ breast cancer by age as well as prognostic features of tumors within a screening program. METHODS: We studied 474,808 women who attended BreastScreen Victoria from January 1, 1993 to December 31, 2000. Of these women, 5,301 were diagnosed with invasive cancer and 1,127 were diagnosed with ductal carcinoma in situ. We used generalized additive models to model age-incidence rates for invasive cancers and ductal carcinoma in situ separately by users and nonusers of hormone replacement therapy at most recent screen. Nonparametric trends for ordered groups and regression methods were used to investigate trends in size, grade, and nodal involvement for invasive tumors by type of attendance and time since previous negative screen for age group. RESULTS: The incidence of ductal carcinoma in situ among women with a previous negative screen clearly declined after age 70 irrespective of hormone replacement therapy use. At subsequent screen, the age-incidence curve for invasive breast cancer flattened at ages 60 to 75 years and then increased only for women taking hormone replacement therapy. Tumor size at diagnosis declined with age at both first round (P = 0.15) and subsequent round (P = 0.08). The proportion of poorly differentiated tumors also decreased with age, with the smallest proportion of grade III tumors diagnosed in women ages > or = 75 years (P = 0.09 for first screen and P = 0.05 for subsequent screen). The presence of positive nodes at diagnosis declined with age (P < 0.001) for both first and subsequent screening rounds. CONCLUSION: Older age is associated with more favorable prognostic tumor features and a lower incidence of ductal carcinoma in situ among subsequent attenders of screening. When making decisions regarding continuing screening, older women and their physicians should also consider the presence of other comorbid conditions that may mitigate any impact of screening on mortality.

Age Factors↗

PubMed1997

An interim determination of health gain from oral cancer and precancer screening: 2. Developing a model of population screening.

OBJECTIVE: To design a simulation model of population screening for oral cancer and precancer and to obtain estimates of quality adjusted life years (QALYs) and lives gained from screening, using decision analysis. DESIGN: A hypothetical opportunistic screening programme was compared with the status quo (no screening). Variables included in the model were attendance (50 per cent of the eligible population); prevalence of oral cancer (0.098 per cent) and precancer (2.57 per cent), positive (0.67) and negative (0.99) predictive values of screening, stage distribution of cancer (40 per cent stage 1, 60 per cent stage 2+ without screening; 60 per cent stage 1, 40 per cent stage 2+ with screening); average survival (precancer, 19.2 years; stage 1, 14.6 years; stage 2+, 10.8 years); and the public's perceived utilities of the various outcomes (health, 1.00; precancer, 0.92; stage 1 cancer, 0.88; stage 2+ cancer, 0.68). One cycle of the programme was modelled. SETTING: Screening would be carried out in dental practices. PARTICIPANTS: A notional population of 100,000 adults of average age 55 years and 20 years life expectancy entered each decision pathway (screening or status quo). INTERVENTIONS: Systematic clinical examination of the oral soft tissues. OUTCOME MEASURES: QALYs and equivalent lives saved. RESULTS: Assuming 50 per cent attended, the population offered screening achieved 1,993,094 QALYs. With no screening the corresponding end point was 1,992,982 QALYs. The gain from screening was therefore 56 QALYs representing an equivalent of 2.8 lives saved. CONCLUSIONS: Though a simplification, this model is likely to be more reliable than intuitive prediction and is amenable to sensitivity analysis of different screening strategies. A modest health gain from screening was predicted by the model.

Adult↗

PubMed1998

Mammography screening for breast cancer in Copenhagen April 1991-March 1997. Mammography Screening Evaluation Group.

A biennial mammography screening programme started for all women aged 50-69 in the municipality of Copenhagen, Denmark, on 1 April 1991. We report here on the outcome of the first three invitation rounds. Copenhagen has approximately 40,000 female residents aged 50-69. The Copenhagen Municipality IT Service runs the data files and issues the invitations based on the daily updated population register. Screening takes place at a special clinic at Bispebjerg Hospital, and since 1 September 1996 all assessment and surgery take place at Rigs-hospitalet. The first invitation round covered the period April 1991 to April 1993, the second invitation round the period May 1993 to May 1995, and the third invitation round the period June 1995 to March 1997. By now in total 120,772 invitations have been issued, 84,036 screening tests have been performed, 4110 women have been assessed with additional tests, 1057 women have undergone surgery, and 697 cases of invasive breast cancer cases or carcinoma in situ have been detected. The number of women screened during each of the three invitation rounds as a percentage of the target population aged 50-69 was 71%, 65% and 63%, respectively. It is possible for a woman to notify the programme if she does not want to be invited, and this caused the coverage to decline. The participation rate among the invited women was 71%, 69% and 70%, respectively. Ninety percent of those screened the first and second times and invited the third time participated. The number of screen detected invasive breast cancers of carcinoma in situ cases per 1000 participants during each invitation round was 11.9; 6.3; and 6.1, respectively. When compared with the incidence of invasive breast cancer in Copenhagen before screening, the ratios were 4-7 for all first time screened and 2 for all second or third time screened. Among the 697 screen detected cases, 84% were invasive breast cancers and 11% carcinoma in situ in women not previously known with breast cancer, and 5% were second primary breast cancers. Fifty two invasive interval cancers were found when women who tested negative during the first invitation round were followed up for two years in the Danish Cancer Register and the files of invasive breast cancers of the Danish Breast Cancer Cooperative Group. Compared with the incidence of invasive breast cancer in Copenhagen before screening this gave a proportionate interval cancer rate of 0.34 (95% confidence interval 0.26-0.45). Eight percent of the women who ever participated in the programme had experienced at least one false positive screening test, and 10% of the women who participated all three times in the programme had experienced at least one false positive test. The assessment was an efficient procedure for the sorting out of the false positive screening tests. During the third invitation round, three quarters of those who underwent surgery had either invasive breast cancer or carcinoma in situ. The participation rate in the present programme is relatively low as are the participation rates in other large cities. However, the programme is well accepted among those who participate, as a high proportion of these women come back. The detection rates compared with the previous incidence of invasive breast cancer indicate a good performance of the programme, and so does the proportionate interval cancer rate following the first invitation round. The programme is thus functioning well. The relatively low coverage and the flow in the target population limit the reduction in breast cancer mortality to be expected from the screening programme in the Copenhagen municipality.

Aged↗

PubMed2002

Large-scale randomized prostate cancer screening trials: program performances in the European Randomized Screening for Prostate Cancer trial and the Prostate, Lung, Colorectal and Ovary cancer trial.

Two large-scale randomized screening trials, the Prostate, Lung, Colorectal and Ovary (PLCO) cancer trial in the USA and the European Randomized Screening for Prostate Cancer (ERSPC) trial in Europe are currently under way, aimed at assessing whether screening reduces prostate cancer mortality. Up to the end of 1998, 102,691 men have been randomized to the intervention arm and 115,322 to the control arm (which represents 83% of the target sample size) from 7 European countries and 10 screening centers in the USA. The principal screening method at all centers is determination of serum prostate-specific antigen (PSA). The PLCO trial and some European centers use also digital rectal examination (DRE) as an ancillary screening test. In the core age group (55-69 years), 3,362 of 32,486 men screened (10%) had a serum PSA concentration of 4 ng/ml or greater, which is 1 cut-off for biopsy (performed in 84%). An additional 6% was referred for further assessment based on other criteria, with much less efficiency. Differences in PSA by country are largely attributable to the age structure of the study population. The mean age-specific PSA levels are lower in the PLCO trial (1.64 ng/ml [in the age group 55-59 years], 1.80 [60-64 years] and 2.18 [65-69 years) than in the ERSPC trial (1.28-1.71 [55-59], 1.75-2.87 [60-64] and 2.48-3.06 [65-69 years]). Detection rates at the first screen in the ERSPC trial range from 11 to 42/1,000 men screened and reflect underlying differences in incidence rates and screening procedures. In centers with consent to randomization design, adherence in the screening arm is 91%, but less than half of the men in the target population are enrolled in the trial. In population-based centers in which men were randomized prior to consent, all eligible subjects are enrolled, but only about two-thirds of the men in the intervention arm undergo screening. Considerable progress has been made in both trials. Enrollment will be completed in 2001. A substantial number of early prostate cancers have been detected. The differences between countries seem to reflect both underlying prostate cancer incidence and screening policy. The trials have the power to show definitive results in 2005-2008.

Aged↗