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Copyright of GMS Health Technology Assessment is the property of German Medical Science Publishing House gGmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of GMS Health Technology Assessment is the property of German Medical Science Publishing House gGmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of GMS Health Technology Assessment is the property of German Medical Science Publishing House gGmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Autism spectrum disorders (ASD) comprise typical or infantile autism (Kanner syndrome), Asperger's disorder and atypical autism or pervasive developmental disorder - not otherwise specified. The syndrome is characterized by deficits in (1) verbal and nonverbal communication, (2) reciprocal social interaction and (3) repetitive patterns of behaviour, interests and activities. Early behavioural interventions are based on learning theory and behaviour therapy. They take into account specific deficits in perception, emotional reactions, social interaction and communication. In Germany, these comprehensive models are not widely evaluated and implemented., Research Questions: What are the clinical effectiveness and safety of early behavioural or skills-based early interventions in autism compared to other interventions or to treatment as usual?What are specific factors responsible for the effectiveness?What are the cost-effectiveness and cost consequences of different early interventions in autism?Which legal, social and ethical aspects are relevant with regard to the implementation of the respective interventions in persons with autism?, Methods: Following a systematic review of the literature, controlled studies on early behavioural or skills-based interventions published since 2000 in English or German with children until the age of twelve are included and critically appraised. Studies must have at least ten participants per intervention group., Results: In total, 15 publications based on 14 studies, eight systematic reviews and one health economic study are included. Most studies evaluate early interventions based upon the Lovaas model (Early intensive behavioural treatment (EIBT), Applied behavioural analysis (ABA)). Other evaluate pragmatic interventions or interventions based on other theoretical models like specific parent interventions, responsive education and prelinguistic milieu teaching, joint attention, symbolic play, and picture exchange communication system. Behaviour analytic interventions referring to the Lovaas model remain the most empirically evaluated early interventions in autism. Preschool children with autism can achieve improvements in cognitive and functional domains when treated within behavioural interventions with a frequency of at least 20 hours per week. It is not clear which is the minimum duration of effective interventions, and which active components are necessary for the effectiveness. There was no high quality evidence for other comprehensive early interventions. The identified health economic study is not suitable to evaluate the cost-effectiveness or cost consequences of early interventions. No publications concerning legal, ethical or social aspects were identified. The financial situation of persons with autisms and their families will be improved through the implementation of the "Pflege-Weiterententwicklungsgesetz" (Pf-WG). Further questions concern the organisation of care and the legal representation of autistic patients. Ethical questions arise mainly in the context of the equal supply of care to each individual patient in all regions of the country and the situation of the caregivers., Discussion: There are only a few studies with high methodology evaluating early interventions in children with autism. Most studies have a short duration with a lack of blinded outcome assessment in many cases. The lack of high quality comparative studies does not allow answering questions of comparative effectiveness of early interventions in autism. It can be concluded that interventions referring to the Lovaas model seem to have the highest effectiveness. This seems to be especially true when they are run clinic-based. However, there was no solid evidence with regard to factors responsible for the effectiveness of programms according to the ABA model. With regard to communication improvement, a systematic parent training seems to be superior to treatment as usual where a mixture of therapeutic elements is used. As well for clinical and health economic studies there is a substantial problem of generalisability into the German context. The identified health economic study is not suitable to evaluate the cost-effectiveness or cost consequences of early interventions., Conclusion: Based on the available studies, there is no sufficient evidence for any of the evaluated behavioural early intervention programmes. Studies suggest that preschool children with autism in behavioural intervention programmes with a frequency of at least 20 hours per week can achieve improvements in cognitive and functional domains. There is no evidence that in a substantial portion of the children a normal development can be achieved by early interventions. Most research evidence is available for ABA. A minimal necessary intensity of interventions to achieve positive outcomes cannot be derived from literature. There are no valid statements possible as to cost-effectiveness or consequences of these interventions. Effective early interventions may reduce total autism costs in the long run. This may be achieved when the initial high treatment expenditures are more than compensated later if persons with this disorder have better social functioning.

Introduction: Essential precondition for the development of cervical cancer is a persistent human papillomavirus (HPV) infection. The majority - approximately 70% - of cervical carcinomas is caused by two high-risk HPV types (16 and 18). Recently, two vaccines have been approved to the German market with the potential to induce protection against HPV 16 and HPV 18 among additional low-risk virus types., Objectives: To analyse whether HPV vaccination is effective with regard to the reduction of cervical cancer and precursors of cervical carcinoma (CIN), respectively? Does HPV vaccination represent a cost-effective alternative or supplement to present screening practice? Are there any differences concerning cost-effectiveness between the two available vaccines? Should HPV vaccination be recommended from a health economic point of view? If so, which recommendations can be conveyed with respect to a (re)organization of the German vaccination strategy? Which ethical, social and legal implications have to be considered?, Methods: Based on a systematic literature review, randomized controlled trials (RCT) looking at the effectiveness of HPV vaccination for the prevention of cervical carcinoma and its precursors - cervical intraepithelial neoplasia - have been identified. In addition, health economic models were identified to address the health economic research questions. Quality assessment of medical and economic literature was assured by application of general assessment standards for the systematic and critical appraisal of scientific studies., Results: Vaccine efficacy in prevention of CIN 2 or higher lesions in HPV 16 or HPV 18 negative women, who received all vaccination doses, ranges between 98% and 100%. Side effects of the vaccination are mainly associated with injection site reactions (redness, turgor, pain). No significant differences concerning serious complications between the vaccination- and the placebo-groups were reported. Results of base case scenarios in the identified health economic modeling analyses range from approximately 3,000 Euro to 40,000 Euro per additional QALY (QALY = Quality-adjusted life year) and approximately 9,000 Euro to 65,000 Euro per additional life year (LYG), respectively., Discussion: The included studies show that both available HPV vaccines are effective in preventing HPV 16 and HPV 18 infections and probable resulting premalignant lesions of the cervix. However, the duration of protection is currently unclear. With regard to side effects, the vaccination can be considered as secure. Nevertheless, the number of cases within the clinical studies is not sufficient to determine the occurrence of rarely occurring (severe) adverse events in a reliable way. A reduction in the incidence and induced mortality through cervical cancer in Germany is not only depending on the vaccine's clinical efficacy. Effects of the new technology on the overall participation rate in screening programs and the resulting vaccination rate and immunization status are also important factors. The results of identified health economic models vary substantially due to the heterogeneity of methodological approaches as well as chosen input parameters. However, almost all model-based analyses reached the conclusion that the implementation of a vaccination with lifelong protection can be considered as cost-effective, if the present screening practice continues. A comparison of the two vaccines shows, that the cost effectiveness ratios are more favorable with the quadrivalent vaccine than with the bivalent alternative when considering QALY as primary outcome parameter. The reason for this finding might be that in the case of the quadrivalent vaccine the prevention of genital warts can also be incorporated into the analysis. Variations of the duration of protection as well as the discounting rate were identified as the primary influencing factors of cost-effectiveness results., Conclusion: Implementation of HPV vaccination might lead to a reduction of cervical cancer in immunized women. However, uptake of immunization should be accompanied by further studies in order to assess long-term effectiveness and safety aiming at an optimization of possible implementation processes. High numbers of participants are of particular importance regarding immunization. This has to be backed up by programs to optimize early detection - as this affects even those women who already underwent immunization. Since cost-effectiveness evidence might be significantly affected by the unclear duration of protective benefits, a final verdict on the vaccination's cost-effectiveness in the German setting is not possible. Hence, risk-sharing-agreements between third-party payers and manufacturers would pose an option to balance the consequences of uncertainty towards the duration of protection on cost-effectiveness.

Introduction: Incisional hernias are a common complication following abdominal surgery and they represent about 80% of all ventral hernia. In uncomplicated postoperative follow-up they can develop in about eleven percent of cases and up to 23% of cases with wound infections or other forms of wound complications. Localisation and size of the incisional hernia can vary according to the causal abdominal scar. Conservative treatment (e. g. weight reduction) is only available to relieve symptoms while operative treatments are the only therapeutic treatment option for incisional hernia. Traditionally, open suture repair was used for incisional hernia repair but was associated with recurrence rates as high as 46%. To strengthen the abdominal wall and prevent the development of recurrences the additional implantation of an alloplastic mesh is nowadays commonly used. Conventional hernia surgery as well as minimally invasive surgery, introduced in the early 90s, make use of this mesh-technique and thereby showed marked reductions in recurrence rates. However, there are possible side effects associated with mesh-implantation. Therefore recommendations remain uncertain on which technique to apply for incisional hernia repair and which technique might, under specific circumstances, be associated with advantages over others., Objectives: The goal of this HTA-Report is to compare laparoscopic incisional hernia repair (LIHR) and conventional incisional hernia repair with and without mesh-implantation in terms of their medical efficacy and safety, their cost-effectiveness as well as their ethical, social und legal implications. In addition, this report aims to compare different techniques of mesh-implantation and mesh-fixation as well as to identify factors, in which certain techniques might be associated with advantages over others., Methods: Relevant publications were identified by means of a structured search of databases accessed through the German Institute of Medical Documentation and Information (DIMDI) as well as by a manual search. The former included the following electronic resources: SOMED (SM78), Cochrane Library - Central (CCTR93), MEDLINE Alert (ME0A), MEDLINE (ME95), CATFILEplus (CATLINE) (CA66), ETHMED (ED93), GeroLit (GE79), HECLINET (HN69), AMED (CB85), CAB Abstracts (CV72), GLOBAL Health (AZ72), IPA (IA70), Elsevier BIOBASE (EB94), BIOSIS Previews (BA93), EMBASE (EM95), EMBASE Alert (EA08), SciSearch (IS90), Cochrane Library - CDSR (CDSR93), NHS-CRD-DARE (CDAR94), NHS-CRD-HTA (INAHTA) as well as NHSEED (NHSEED). The present report includes German and English literature published until 31.08.2005. The search parameters can be found in the appendix. No limits were placed on the target population. The methodological quality of the included clinical studies was assessed using the criteria recommended by the "Scottish Intercollegiate Guidelines Network Grading Review Group". Economic studies were evaluated by the criteria of the German Scientific Working Group Technology Assessment for Health Care., Results: The literature search identified 17 relevant medical publications. One of these studies compared laparoscopic and conventional surgery with and without mesh for incisional hernia repair, while 16 studies compared laparoscopic and conventional surgery with mesh for incisional hernia repair. Among these studies were 14 primary studies (one randomised controlled trial (RCT), two systematic reviews and one HTA-Report. The only study comparing laparoscopic and conventional surgery without mesh found substantial differences in terms of baseline characteristics between treatment groups. The outcome parameters showed decreased recurrence rates for the laparoscopic repair and similar safety of the procedures. Studies comparing laparoscopic and conventional surgery with mesh found similar outcome in terms of medical efficacy and safety. However, there was a trend towards lower recurrence rates, length of hospital stay, and postoperative pain as well as decreased complication rates for laparoscopic repair in the majority of studies. The impact of the technique of mesh-implantation and -fixation as well as the impact of certain factors on the choice of technique has not been systematically assessed in any of the studies., Discussion: All identified studies suffer from significant methodological weaknesses, such as differences between treatment groups, mainly due to the non-randomised study design, small treatment groups causing low case numbers and lack of statistical power as well as the neglect of important risk factors or adjustment for those. Therefore, no conclusive differences could be identified concerning compared operative techniques, mesh-implantation and -fixation techniques or certain risk factors. Only the comparison of laparoscopic and conventional technique with mesh provides some evidence for a trend towards similar or slightly improved outcome in terms of medical efficacy and safety for the laparoscopic technique. However, there is still a great need for further research to investigate these questions. Basically, there is no full economic evaluation focussing on the relevant alternatives. Cost compareisons were available, even though only briefly attached to clinical research results. None of the studies primarily aimed to investigate costs or even cost-effectiveness., Conclusion: When deciding on the choice of operative technique for incisional hernia repair, surgeons take various considerations into account, including patient characteristics, hernia characteristics and their own experience. The studies included in this HTA did not provide conclusive evidence to answer the research questions. Nonetheless, laparoscopic surgery demonstrated a trend towards similar or slightly improved outcome following incisional hernia repair. However, for more conclusive recommendations on the choice of operative technique, high quality trials are required From the economic perspective, alternative methods are not yet assessed. Only five of the studies involve a cost analysis, though in an insufficient manner. None of the studies identified were laid out as a health economic evaluation. Hence, further research is strongly recommended.

Introduction: The introduction of a screening programme for cervical carcinoma in Germany has led to a significant reduction in incidence of the disease. To date, however, diagnosis in Germany has been based solely on cervical cytology, which has been criticised because of a low sensitivity and consequently high rate of false negative results. Because an infection with the human papillomavirus (HPV) previously was found to be a necessary aetiological factor in the development of cervical cancer, there has been some discussion that HPV testing should be included in cervical cancer screening., Objectives: How do HPV tests compare to cytological tests in terms of sensitivity and specificity, and what are the effects of screening for cervical carcinoma in Germany? Is there health economic evidence that may foster an inclusion of HPV testing into national screening programms?, Methods: A systematic literature review was performed, including studies that compared the HPV test to cervical cytology in terms of sensitivity and specificity in the diagnosis of CIN 2+ (CIN=Cervical Intraepithelial Neoplasia). In addition, a systematic review of the relevant health economic literature was performed to analyze cost-effectiveness in the German setting., Results: A total of 24 studies fulfilled the inclusion criteria. One study consisted of three substudies. Hence, results of 26 comparisons of HPV and cytology are reported. In 25 of these, the HPV test was more sensitive than cytology, whereas cytology had better specificity in 21 studies. The combination of HPV test and cytology increased sensitivity. Variability in results was considerably larger for cytology than for HPV testing. Results of the economic meta-analysis suggest that in health care settings with already established PAP screening programms, cost-effectiveness strongly depends on screening intervals. In analyses comparing HPV screening to conventional PAP screening with two-yearly intervals, only 25% of the HPV strategies were found to be cost-effective, whereas in comparison with one-, three-, and five-yearly PAP screening, the percentage of overall cost-effective HPV strategies was 83%, 55%, and 92%, respectively. Results for annual screening intervals are based on the assumption of complete screening compliance, which has to be further evaluated in decision analyses in the future adapting to the German health care setting., Discussion: Including HPV testing in screening procedures for cervical carcinoma could lead to a reduction in false positive results. Doing so would involve one of the following approaches: a) combining the HPV test with cytology, or b) using cytology as triage in HPV-positive women. The most appropriate interval between screening tests and the best age to start or stop screening remains to be determined. At this point a formal health economic decision analyses may help in resolving those questions, additionally incorporating compliance and adherence within different screening scenarios., Conclusion: Considering medical evidence weighing the question whether HPV testing should be implemented into screening routine may not be if but how to do so. Open questions remain in setting the length of optimal screening intervals, the age range in which to screen, and the combination or sequence of existing cytology and HPV testing. Answers to those questions will be gathered in the very near future through large international clinical trials. Cost-effectiveness of implementing HPV testing is likely to exist in the management of borderline or unclear smears in triage treatment as well as in certain scenarios of primary screening within the German health care setting.

Introduction: With 3.2% of all cancer cases in 2002, cervical carcinoma is the tenth most common cancer in Germany and causes 1.8% of all cancer deaths in women in Germany. To date diagnosis in Germany solely has been based on cervical cytology which has been criticised due to its low sensitivity and consequently high rate of false negative results., Objectives: How does colposcopy compare to cytological tests in terms of sensitivity and specificity, and what may be the effects of changes in screening for cervical carcinoma in Germany? Is there health economic evidence that may foster an inclusion of colposcopy into national screening programms?, Methods: A systematic literature review was performed, including studies that compared colposcopy to cervical cytology in terms of sensitivity and specificity. In addition, a systematic review of the relevant health economic literature was performed to analyse cost-effectiveness issues relevant to the German setting., Results: A total of four studies fulfilled the inclusion criteria, of which only two were of high methodologic quality. In all studies, the sensitivity of colposcopy was lower than that of cytology. In three studies the specificity of colposcopy was lower than that of cytology, in one study specificity of colposcopy and cytology was similar. No health economic data suggesting positive effects of adding colposcopy in primary screening could be identified., Discussion: Only few studies have compared the test criteria of colposcopy with those of cytology for screening in cervical cancer. In all studies, sensitivity of colposcopy was even lower than the sensitivity of cytology, which has been critisized because of its low sensitivity., Conclusion: Based on the present data, an inclusion of colposcopy in primary cervical cancer screening programmes can not be recommended.

Background: The cataract (Cataracta senilis) is the most frequent eye disease of elderly people worldwide. In Germany, the cataract operation - with currently 450,000 interventions each year the most frequent operation in ophthalmology - can be seen as routine surgery. The age related macular degeneration (AMD) is a further one of the most common, age-related eye diseases and the most frequent cause of blindness of elderly people in industrial nations. Due to demographic changes an increasing number of patients will suffer from cataract and AMD at the same time. This coincidence leads to a greater interest in the question of a mutual influence of both diseases, respectively their therapies, on each other., Objectives: The aim of this report was the evaluation of the medical and health economic effects of cataract operations on the development and progression of an age related macular degeneration (AMD). It was differentiated between first manifestations of AMD, progression of early stages of AMD and influence on further impairment in late stages of AMD., Methods: The relevant publications for this report were identified by DIMDI via structured database enquiry as well as common, self-made enquiry and were evaluated, based on the criteria of evidence based medicine. The present report included German and English literature published since 1983., Results: The database enquiry generated a record of 2769 issue-related publications. Eight medical publications were eligible for analysis in the course of the present HTA report. No relevant studies on health economical, ethical, social or legal issues could be included. Three epidemiological cohort studies provided some evidence for a promoting influence of cataract extractions on the progression of early types of AMD. Two of the epidemiological studies assessed the risk of first manifestation of AMD after cataract extraction. Both came up with up with increased incidences that did not reach statistical significance despite a large number of participants. Only one out of two clinical studies looked at further impairment in late stages of AMD and could not find an interrelation with cataract extraction. Thus the available evidence was not sufficient to come to a conclusion on the contribution of cataract extractions to the first manifestation of AMD and to the further impairment in late stages., Discussion: The presentation of the evaluated literature made clear that only a small number of publications dealt with the development of age related macula degeneration in consequence of a cataract extraction. The overall scientific level of evidence of these articles was not very high. Therefore it was not possible to obtain a well-defined conclusion on the effect of a cataract extraction on the development or progression of an age related macula degeneration., Conclusion: Additional well conducted clinical trials, that offer a sufficient number of patients, length of study period and adequate control for confounding variables like age and severity of cataract, are urgently needed. Health economic, ethical, social and legal aspect of the problem could and should be investigated after clarification of the mentioned medical issues.

Introduction: Arteriosclerotic changes can lead to circulatory disturbances in various areas of the human vascular system. In addition to pharmacological therapy and the management of risk factors (e. g. hypertension, diabetes, lipid metabolism disorders, and lifestyle), surgical interventions also play an important role in the treatment of arteriosclerosis. Long-segment arterial occlusions, in particular, can be treated successfully with bypass sur-gery. A number of different materials are available for this type of operation, such as autologous vein or pros-thetic grafts comprised of polytetrafluoroethylene (PTFE) or Dacron(®). Prosthetic materials are used especially in the treatment of peripheral artery disease, such as in aortoiliac or femoropopliteal bypass surgery. The present report will thus focus on this area in order to examine the effectiveness of different bypass materials. Among the efforts being made to refine the newly introduced DRG system in Germany, analysing the different bypass materials used in vascular surgery is particularly important. Indeed, in its current version the German DRG system does not distinguish between bypass materials in terms of reimbursement rates. Differences in cost structures are thus of especial interest to hospitals in their budget calculations, whereas both private and statutory health insurance funds are primarily interested in long-term results and their costs., Objectives: The goal of this HTA is to compare the different bypass materials used in vascular surgery in terms of their medical efficiency and cost-effectiveness, as well as with regard to their ethical, social and legal implications. In addition, this report aims to point out the areas in which further medical, epidemiological and health economic research is still needed., Methods: Relevant publications were identified by means of a structured search of databases accessed through the German Institute of Medical Documentation and Information (DIMDI), as well as by a manual search. The for-mer included the following electronic resources: SOMED (SM78), Cochrane Library - Central (CCTR93), MEDLINE Alert (ME0A), MEDLINE (ME95), CATFILEplus (CATLINE) (CA66), ETHMED (ED93), GeroLit (GE79), HECLINET (HN69), AMED (CB85), CAB Abstracts (CV72), GLOBAL Health (AZ72), IPA (IA70), El-sevier BIOBASE (EB94), BIOSIS Previews (BA93), EMBASE (EM95), EMBASE Alert (EA08), SciSearch (IS90), Cochrane Library - CDSR (CDSR93), NHS-CRD-DARE (CDAR94), NHS-CRD-HTA (INAHTA), and NHS-EED (NHSEED). The present report included German and English literature published between the years 1999 and 2004. A list of the search parameters can be found in the appendix. No limits were placed on the target population, and the methodical quality of the included studies was determined using standardised checklists., Results: THE STUDIES INCLUDED IN THIS HEALTH TECHNOLOGY ASSESSMENT COMPARED THE FOLLOWING BYPASS MATERIALS: autologous vein, human umbilical vein (HUV) and synthetic materials such as PTFE or Dacron(®). Both the systematic reviews and the randomised controlled trials comparing autologous vein grafts to other bypass materials come to the conclusion that autologous vein is superior to all other materials. From a medical viewpoint, there are no clear differences between the various synthetic materials. To date, the subject of bypass materials in vascular surgery has not been addressed comprehensively from an economic point of view. Indeed, we were able to identify only one publication that compared the cost of various bypass materials. The remaining health economic studies did not compare costs, cost effectiveness, or quality of life associated with the use of various bypass materials., Discussion: When deciding which bypass material to use, vascular surgeons take a number of medical considerations into account, including the bypass area, the availability of autologous vein, the amount of operation time available, and the health status of the patient. The studies included in this health technology assessment demonstrate that autologous vein is usually the preferred material for bypass grafts. In contrast, comparisons of various synthetic materials did not show any specific differences. It remains to be seen whether studies on newly developed synthetic materials will show these to have any particular advantages. The randomised controlled trials included in the present report were limited by a number of methodological weaknesses, such as different methods for determining patency rates, sample size and power problems, the interpretation of non-significant results, and a lack of consideration of additional factors. From an economic point of view, there is still great need for further research, and we have attempted to describe a number of pressing questions for health economic studies in the present report.