A cohort study of mammography screening finds that comorbidity measures are insufficient for controlling selection bias.

OBJECTIVE: To examine the potential of claims-based comorbidity measures for controlling selection bias in observational studies of mammography screening. STUDY DESIGN AND SETTING: Based on claims data of a large German Statutory Health Insurance fund, the single comorbidities considered by the Charlson, Elixhauser, Multipurpose Australian Comorbidity Scoring System, and M3 comorbidity measures were identified for mammography screening participants and nonparticipants. Total death rates within 4 years after screening invitation were compared. Cox proportional hazards regressions were performed unadjusted and adjusted for age, federal state of residence, and comorbidity. RESULTS: Among 1,247,919 insured women aged 50-68 years (56.2% participants), 10,311 participants (death rate 375.8/100,000 person-years) and 18,113 nonparticipants (death rate 854.8/100,000 person-years) died from any cause during the follow-up. The unadjusted hazard ratio (HR) for death from any cause for participants vs. nonparticipants was 0.44 (99.9% confidence interval 0.42-0.46). Adjustments attenuated the HR to a maximum of 0.52 (0.50-0.54). CONCLUSION: The lower short-term all-cause mortality among participants cannot be explained by mammography screening effects and should be interpreted as selection bias. Adjusting for comorbidities only slightly attenuated this bias. Future studies should examine whether claims data include further information that is beneficial to adequately control selection bias in observational studies of mammography screening.

[ICD coding quality for outpatient cancer diagnoses in SHI claims data]. / ICD-Codierqualität ambulanter Krebsdiagnosen in GKV-Routinedaten.

BACKGROUND: Despite their importance for the morbidity-oriented risk structure compensation scheme, the ICD coding quality for outpatient diagnoses is often criticized. However, the coding quality for outpatient cancer diagnoses remains unclear. In this study, we examined the ICD-10 coding quality for outpatient breast, prostate and colorectal cancer diagnoses in statutory health insurance (SHI) claims data. METHODS: The cohort study comprised 34,756 members of the BARMER GEK statutory health insurance fund diagnosed with breast, prostate or colorectal cancer in 2012 and with no respective diagnosis in the previous 4 quarters. Using internal validation approaches, we examined the proportion of diagnoses confirmed by persistence (further diagnoses or death) and/or congruence (EBM, OPS and ATC codes). RESULTS: The proportion of diagnoses confirmed by a further diagnosis or death within one quarter of follow-up was 69.8 % for breast cancer, 73.0 % for prostate cancer and 64.6 % for colorectal cancer, increasing to 71.8 %, 74.6 % and 68.0 %, respectively, when considering provision of care using EBM, OPS and ATC codes. By extending the diagnosis-free lead time to 16 quarters and the follow-up time to 4 quarters, the proportion rose to 83.9 %, 85.1 % and 75.8 %, respectively. Results varied by sex, age, the Associations of SHI Physicians and settlement pattern. CONCLUSIONS: Because there were no further indications confirming the incident outpatient cancer diagnoses a proportion of diagnoses remain unconfirmed. When conducting studies based on SHI claims data, these limitations in the ICD coding quality for outpatient cancer diagnoses should be taken into account by using internal validation approaches.

Accuracy of diagnostic antibody tests for coeliac disease in children: summary of an evidence report.

OBJECTIVE: The aim of this study was to summarise the evidence from 2004 to September 2009 on the performance of laboratory-based serological and point of care (POC) tests for diagnosing coeliac disease (CD) in children using histology as reference standard. PATIENTS AND METHODS: We searched MEDLINE and EMBASE for studies reporting on children for tests based on IgA and IgG anti-gliadin (AGA), endomysial (EmA), anti-transglutaminase-2 (TG2), and anti-deamidated gliadin peptides (DGP) antibodies or POC tests. For inclusion, histological analysis of duodenal biopsies and sensitivity and specificity for index tests had to be reported. Data were pooled and summary measures calculated for sensitivity, specificity, positive and negative likelihood ratios ("LR+", "LR-"), and diagnostic odds ratios (DOR). In case of elevated statistical heterogeneity, studies reaching 90% sensitivity or specificity were reported. RESULTS: A total of 2510 articles were reviewed; 16 entered meta-analysis, reporting on 3110 patients (1876 with CD, 1234 without CD). For IgA-EmA, sensitivity was ≥90% in 7/11 studies and pooled specificity 98.2%. For IgA-anti-TG2, 11/15 studies yielded sensitivities ≥90% and 13/15 specificities ≥90%. For IgA-DGP, sensitivity ranged between 80.7% and 95.1% (specificity 86.3%-93.1%); for IgG-DGP between 80.1% and 98.6% (specificity 86.0-96.9%). IgA-EmA had the highest pooled DOR (554) and LR+ (31.8) for a laboratory test, followed by IgA-anti-TG2, IgG-DGP, IgA-DGP and IgA-AGA. POC tests showed a pooled sensitivity of 96.4% for IgA-TG2 (specificity 97.7%). CONCLUSIONS: IgA-EmA and IgA-anti-TG2 tests appear highly accurate to diagnose CD. IgG-anti-DGP tests may help in excluding CD. IgA-AGA and IgA-DGP tests show inferior accuracy. POC tests may achieve high accuracy in the hands of experienced readers, but IgA-anti-TG2/EmA were superior.

Carpal tunnel syndrome as an occupational disease.

BACKGROUND: Carpal tunnel syndrome (CTS) has been listed since 2003 in the European Union's list of occupational diseases. In 2001, it took sixth place in frequency among all occupational diseases recognized in the European Union. It was not listed as an occupational disease in Germany until July 2009, when the medical expert advisory panel of the German Federal Ministry of Labour and Social Affairs issued an evaluative paper supporting its listing. METHODS: We selectively reviewed the literature on the potential causation of CTS by occupational activities. RESULTS: Repetitive manual work tasks involving flexion and extension at the wrist, forceful grip with the hand, and/or vibrations of the hand and arm, such as are induced (for example) by hand-held vibrating tools, can damage the median nerve and cause CTS. A combination of these exposures has been found to raise the risk of CTS with a more than additive effect. Harmful exposures arise in a wide variety of occupations; in judging whether a particular case of CTS is of occupational origin, the physician has to consider the actual manual tasks performed by the patient, rather than merely the job title. Working at a computer keyboard seems not to raise the risk of CTS. CONCLUSION: The causation of CTS by occupational activities, either alone or in combination with other factors, has been well documented by epidemiological data and is pathophysiologically plausible. In Germany, a physician who diagnoses carpal tunnel syndrome in an employee with a relevant, damaging occupational exposure is required to report the case to the German Social Accident Insurance.

[Planning, implementation and evaluation of cancer screening programs]. / Entwicklung, Durchführung und Evaluation von Programmen zur Krebsfrüherkennung Ein Positionspapier.

Members of the Cancer Epidemiology Work Group within the German Epidemiology Society and Dr Antes of the German Cochrane Center will present a review of the epidemiological aspects of cancer screening programs. Prior to the implementation of a cancer screening program, there should be clear evidence from randomized controlled trials showing a disease-specific mortality reduction by screening. For target entities with the potential to reduce incident invasive cancers- such as cervical and colorectal cancer - the search of evidence should also include cancer incidence reduction. Monitoring of the screening program is essential and should include: the test, the assessment of test-positives, therapy or other interventions, and a cause of death evaluation. It is important to show that the benefit of a mortality reduction is not outweighed by adverse screening effects. In the past, German cancer screening activities were lacking essential components of screening programs like a central unit inviting the target population, standardized documentation and reporting as well as independent audits. The new Mammography Screening Program for the first time offers a screening test in Germany that is embedded in a quality monitoring program evaluating at least intermediate outcome parameters.

Diagnostic agreement in the histopathological evaluation of lung cancer tissue in a population-based case-control study.

Only few studies have compared the agreement of histological lung carcinoma diagnosis of a population-based case series and an independent pathology review. We analyzed data of our population-based lung cancer case-control study to determine the agreement in the histopathological evaluation of lung cancer. Six-hundred and sixty-eight out of 1004 interviewed male and female lung cancer cases were histologically evaluated according to the 1981 WHO classification by regional pathologists and a central pathologist who was blinded to the evaluations of the regional pathologists. The observed agreement was 0.65 with kappa = 0.54 (95% CI: 0.49-0.58). It was highest for small-cell carcinoma (0.94; kappa = 0.82) and lower for squamous-cell carcinoma (0.81; kappa = 0.58) and adenocarcinoma (0.81; kappa = 0.55). Agreement was slightly higher among women than men. The observed agreement among non-smoking cases was 58% as compared to 67% heavy smoking cases. The moderate agreement for squamous-cell and adenocarcinoma complicates epidemiological studies that address these histological subtypes.

[The German Guideline Clearinghouse on Breast Cancer: the need for frequent updating of breast cancer guidelines requires effective guideline updating procedures]. / Leitlinien-Clearingverfahren Mammakarzinom: Die Notwendigkeit einer häufigen Aktualisierung von Mammakarzinom-Leitlinien erfordert effektive Vorgehensweisen bei der Fortschreibung von Leitlinien.

In order to promote the quality of health care and guidelines in Germany the German Guideline Clearinghouse (Sponsors: German Medical Association, National Association of the Statutory Health Insurance Physicians, German Hospital Federation, Associations of the Sickness Funds and the Statutory Pension Insurance) was established at the Agency for Quality in Medicine (AQuMed) in 1999. The results of the 10th Guideline Clearing Project, the Guideline Clearing Report "Breast Cancer", were published in December 2003. In a systematic search using English/German language guideline databases and literature databases (Medline, Healthstar, Embase), 16 national guidelines were identified which were in accordance to the inclusion criteria (breast cancer treatment; German or English language; published after 1992; new guideline or genuine update (no adaptation); recommended for country-wide implementation). The methodological quality of these 16 guidelines was evaluated using the appraisal instrument of the German Guideline Clearinghouse, the checklist "Methodological Quality of Clinical Practice Guidelines". A peer review of the guidelines was performed by a multidisciplinary focus group of experts (intended guideline users from clinical and ambulatory settings as well as patients). This group consented comments and recommendations for actions of health care policy makers in Germany for a German breast cancer guideline based on examples from the appraised guidelines. None of the identified guidelines contained information about all of the 24 key topics that the focus group considered to be relevant for a German national guideline. The selected exemplary text extracts from the evaluated guidelines can be used as benchmarks and example sources for the development of a national German breast cancer guideline. From the beginning, patients should be involved in the development process within a multidisciplinary team. Due to the rapid emergence of new evidence, oncology guidelines need an effective procedure for updating in order to ensure that they are able to promote health care quality by giving current recommendations based on best available evidence. International networks such as the Guidelines International Network (G-I-N) will be helpful to collect and appraise the evidence for the national guideline development groups in an effective way.

[When do screening interventions make sense?]. / Wann sind Screening-Interventionen sinnvoll?

The aim of primary prevention is to reduce incidence. Secondary prevention is intended to lead to early detection of disease, and tertiary prevention aims to prevent reoccurrence of disease. The primary goal of screening is the early detection of disease in asymptomatic persons. Detecting disease at an early stage (lead time) does not necessarily imply an increase in life expectancy. Prior to the implementation of a mass screening programme, its effectiveness must have been demonstrated in randomised trials. Screening ought to be used for common relevant health problems, an accepted treatment method should be available and a recognisable latent or early stage of disease and the test to be applied should be acceptable to a broad population (WHO criteria). Examples include the ongoing national cancer screening programme and the field of occupational health and show that screening programmes do not always follow evidence-based criteria.