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A review of 75 original articles from clinical cancer research in Norway is presented. Articles published in 1993 and with at least one Norwegian author were included in the review. Sixty papers were observational, whereas 15 were experimental. Of the observational studies 44 were retrospective. Most of the papers concerned prognostic factors. Prior hypotheses were explicitly defined in 16 papers only, and less than half of the articles described inclusion and exclusion criteria. Sample size calculations were performed in four papers only. The choice of statistical method was considered to be suitable in 22 of the 58 articles presenting statistical inferences. Problems related to multiple significance testing were rarely addressed, although the median number of p-values reported was as high as 8. Confidence intervals for main findings were presented in 14 papers. For proper planning of studies, as well as for analysis and interpretation of study results, statistical advice is indeed required. [ABSTRACT FROM AUTHOR]

To investigate how urological studies using composite endpoints as the primary outcome were cited. In this quality analysis of citations, three randomized clinical trials each investigating oncological and non-oncological urology were selected for citation analysis based on pre-defined criteria. In total, 531 papers citing the selected studies were reviewed; citations were evaluated based on whether they correctly referred to the composite endpoint and if singleton endpoints were defined and/or discussed. Among the citations, 223/531 (42%) referred to the composite endpoint, of which 217/223 (97.3%) correctly cited the composite endpoint. However, only 91/217 (41.9%) defined and/or discussed the singleton endpoints of the composite endpoint. The lack of a validated instrument for citation analysis was a limitation of this study. Meanwhile, the main strength is the large number of individually analyzed citations. The composite endpoints of urological randomized clinical trials are generally cited without referring to the composite endpoint; when cited, the composite endpoints are described correctly. However, in most cases, without defining or discussing the singleton endpoints. [ABSTRACT FROM AUTHOR]

In the Nordic countries, as in the rest of the world, particle therapy as a radiotherapy modality, is evolving, albeit the hard evidence for the clinical benefit still is scarce. However, a common goal for the Nordic countries is to include a minimum of 80% of the patients treated with particle therapy into clinical trials. In this paper, we summarize the current status of clinical trials involving particle therapy in the Nordic countries, with an overview of both active and coming trials. So far, one is closed for inclusion and data are being analyzed, seven trials are actively recruiting patients and several more trials are underway. No common Nordic trial has yet been designed, nor is in the planning phase, and the authors will discuss the obstacles as well as the opportunities a common Nordic platform may represent. [ABSTRACT FROM AUTHOR]

The article presents summaries of several papers which were presented at the 2010 World Health Organization International Consultation on Prostate Cancer. The papers centered on advances in screening, prevention and therapy for prostate cancer and discussed the future challenges of prostate cancer and its prevention and treatment.

Performing a reliable assessment of chronic pruritus remains a challenge. Electronic diaries are often used, but many of the scales have not been validated. ItchApp© was developed for Android smartphones in order to address this lack. A total of 40 subjects with chronic pruritus completed questionnaires both on paper and with ItchApp© (verbal rating scale, numerical rating scale, dynamic pruritus score) in order to validate the software application. Strong correlations were found for test–retest reliability (intraclass correlation coefficient: 0.865-0.977) and convergent validity (Spearman's r: 0.442-0.924). A feasibility questionnaire for ItchApp© revealed a high level of user friendliness and compliance. This was confirmed in a randomized controlled trial with 68 subjects, for which the clinically important difference in the numerical rating scale values for ItchApp© was calculated (2.61 points). In summary, ItchApp© is a recently developed eDiary that can provide experts with a reliable evaluation of patients with chronic pruritus. It will be made available for future clinical trials. [ABSTRACT FROM AUTHOR]

Objective: Concerns over adverse effects of mercury released from dental amalgam sometimes lead patients to request removal of their amalgam restorations. Several studies report improvement of subjective health after removal of amalgam restorations, but the mechanisms are unclear. The aim of this paper is to present data on long term changes in intensity of health complaints after amalgam removal in a group of patients with health complaints self-attributed to dental amalgam. Data from the five years follow-up in a clinical trial are presented and related to potential determinants of change.Materials and Methods: Patients previously referred to a specialty unit for health complaints attributed to amalgam restorations were included in the study. The 20 participants who were allocated to the treatment group had all amalgam restorations removed and replaced with other dental restorative materials. Intensity of health complaints was calculated from questionnaire data and personality variables were measured by MMPI-2.Results: At the follow-up five years after the amalgam removal was completed, intensity of general health complaints was significantly reduced (p=.001), but the symptom load was still high. The reduction was significantly correlated with concentration of mercury in urine at pre-treatment. There were no significant correlations with personality variables.Conclusions: Removal of amalgam restorations was followed by a long term reduction of general health complaints, which was associated with mercury concentration in urine before amalgam removal. Additional studies are needed to confirm the potential mechanisms for the observed reduction. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the scientific evidence regarding laser technology for removal of carious tissue. Material and methods. A search for literature on the effect of treatment and on economic aspects of laser technology identified 23 papers. No relevant studies on economic aspects were found. Regarding the effect of treatment, 16 papers were selected for assessment according to established criteria. Results. Cavity preparation and caries excavation by erbium laser were evaluated in three studies of medium quality. The time required to remove carious tissue was evaluated in five studies assessed as being of medium quality for this outcome. In four studies the effect of laser treatment on the dental pulp was included as an outcome but, due to the short follow-up time, the quality was assessed as low. Two studies that included the longevity of the restoration as an outcome were also assessed as being of low quality because the follow-up time was inadequate. Patient response was evaluated in three studies, which were assessed as being of medium quality with respect to this outcome. Conclusions. There is limited scientific evidence that laser treatment is as effective as a rotary bur for removing carious tissue. Treatment time is prolonged. There is limited scientific evidence that adults prefer laser treatment. No conclusions can be drawn regarding biological or technical complications, children's perception of laser treatment or the cost-effectiveness of the method. [ABSTRACT FROM AUTHOR]

The aim of this paper was systematically to evaluate the caries-preventive effect of professional fluoride varnish treatments. A search of the literature for articles published between 1966 and August 2003 was carried out in electronic databases, reference lists of articles, and selected textbooks in accordance with the strategy of the Swedish Council on Technology Assessment in Health Care. Out of 302 identified papers, 24 randomized and controlled clinical trials comparing fluoride varnish with placebo, no active treatment or other fluoride preventive regimens of at least 2 years' study duration were included. The trials that met the inclusion criteria were assessed independently and systematically by at least two reviewers and scored from A to C according to predetermined criteria for methodology and performance. The main outcome measure was the preventive fraction expressed as a percentage. The results displayed limited evidence (evidence level 3) for the caries preventive effect of topical applications of fluoride varnishes in permanent teeth. The average prevented fraction was 30% (0-69%) when compared with untreated controls. Inconclusive evidence (evidence level 4) was found for fluoride varnish treatment in the primary dentition and in adults. This systematic review reinforces the need for future clinical research of high quality, incorporating modern concepts of clinical performance and evaluation to assess dental caries control using professional fluoride varnish. [ABSTRACT FROM AUTHOR]

BackgroundColorectal cancer (CRC) is a disease of the older population. The current demographic ageing leads to more elderly patients and is expected to further increase the number of patients with CRC. The objective of the present paper is to outline incidence, mortality and prevalence from 1980 to 2012 and survival data from 1968 to 2012 in Danish CRC patients focusing on the impact of ageing. Material and methodsData were derived from the NORDCAN database with comparable data on cancer incidence, mortality, prevalence and relative survival in the Nordic countries, where the Danish data are delivered from the Danish Cancer Registry and the Danish Cause of Death Registry with follow-up for death or emigration until the end of 2013. This study focuses on the elderly population categorized in six age groups. ResultsThe incidence of CRC has increased over the past three decades. Incidence rate has increased in patients with colon cancer, but showed a decreasing trend in the oldest patients with rectal and anal cancer. Mortality has diminished in younger patients with colon cancer, but increased with increasing age. However, mortality did not increase proportionally to incidence. In rectal and anal cancer mortality has decreased, except among the oldest patients. This correlates to a decreasing incidence rate. Prevalence is widely increasing mainly because of increased incidence and longer survival, which is reflected in the increasing one- and five-year age-specific relative survival after a diagnosis of colon, rectal and anal cancer. ConclusionThe incidence of CRC is increasing, especially in older citizens, and mortality increases with older age. There is limited knowledge on how to optimize treatment in older CRC patients and future focus must be how to select and tailor the treatment for older CRC patients. [ABSTRACT FROM PUBLISHER]

Chronic pruritus is a common symptom and there is an urgent need to test new anti-pruritic substances in highquality clinical trials. However, no widely accepted standardized and validated method for objectively measuring pruritus is yet available. A special interest group of the International Forum for the Study of Itch has been established to assess scoring methods and questionnaires for use in clinical trials. This paper presents our current recommendations. The set of measures we recommend includes pruritus intensity scales, instruments for assessment of scratch lesions, chronic pruritus course, quality of life and patient benefitsen. [ABSTRACT FROM AUTHOR]

Background. Determining the non-inferiority margin is an essential step in the design and interpretation of non-inferiority trials, and this margin should be preferably justified on clinical and statistical grounds. Methods. After a PubMed search for phase III trials in advanced breast cancer (BC) or non-small cell lung cancer (NSCLC) published between January 1998 and December 2009 in 11 leading journals, non-inferiority trials were selected by manual search of the full papers. Results. Twenty-four of 195 trials had a primary non-inferiority hypothesis. When the two six-year study periods were compared, there were time trends within BC and NSCLC, with most non-inferiority trials in BC reported in the first six-year period, and vice-versa for NSCLC. The median sample size was larger for non-inferiority than superiority trials (p < 0.01). The choice of a non-inferiority margin was reportedly justified in only five cases. Non-inferiority trials were more likely than superiority trials to yield positive results (p < 0.001), as were trials in breast cancer (p = 0.02). Conclusions. Non-inferiority margins for cancer trials appear to be chosen mostly on historical grounds. Since nearly three-quarters of non-inferiority trials achieve their primary objective, the extent to which the choice of margins has influence on trial results remains to be determined. [ABSTRACT FROM AUTHOR]

The article summarizes research on prostate cancer which was contained in papers which were presented at the World Health Organization's International Consultation on Prostate Cancer. In the article the author offers his opinions on the research and on the changing relationship between physicians and increasingly informed patients with prostate cancer.

Background. In 2009, the European Randomized Study of Screening for Prostate Cancer (ERSPC) was one of two studies to report interim data on the effect of screening for prostate cancer (PC) on the disease specific mortality. Contradictory results caused considerable discussion and misunderstanding in secondary literature. Methods. This document is based on a non systematic review of recent evidence for and against screening for PC, specifically considering three recently published randomized screening trials [1 - 3]. Results. The ERSPC data are based on a core age group of 162 387 men, aged 55-69 years, who were identified through population registries in seven European countries. Men were randomized between a screening group that received screening at an average of once every four years and a control group. After a median follow-up of nine years, a reduction in the rate of death from PC by 20% was shown which increased to 31% after adjusting for non-compliance and contamination. Overdetection and subsequent overtreatment (with a number needed to treat (NNT) of 48) are considered to be the major down sides of screening. The recently published 14-year results have shown that these down sides strongly depend on the duration of follow-up. In response to the outcomes of the ERSPC, several points of discussion have been brought up by various authors concerning the usefulness of screening considering benefits, harms and costs, the methodology of the ERSPC and the interpretation of its outcomes. Important issues to address regarding PC screening are addressed. Conclusions . This paper sheds a light on the controversial points of the ERSPC as well as on the priority issues of PC screening. On July 2, 2010 the Swedish section of ERSPC (Göteborg screening trial) published their results with a median follow-up of 14 years. With longer follow-up the data confirm the trend seen in improvement of PC mortality and suggest much more favorable future outcomes also with respect to the NNT to prevent one PC death. [ABSTRACT FROM AUTHOR]

Delamination or fracture of composite veneers can occur as a result of improper design of the fiber-reinforced composite (FRC) framework. This in vitro study tested the repair bond strength of restorative composite to aged FRC. The substrate was multiphase polymer matrix FRC (everStick) aged by boiling for 8 h and storing at 37 degrees C in water for 6 weeks. The aged substrate surfaces were wet-ground flat with 1200-grit silicon carbide paper and subjected randomly to 5 different surface treatments: 1) An adhesion primer (Composite Activator) and resin (CA), 2) Silane (EspeSil) and resin (SIL-MP), 3) Silane, adhesive primer, and resin (Clearfil Repair) (CF), 4) Air particle-abrading (CoJet), silane, and resin (CJ-SIL-MP), 5) Resin (Scotchbond Multipurpose Resin) only as control (MP). Restorative composite resin (Z250) was added to the substrate in 2 mm layer increments and light-cured. Subsequently, every surface treatment group was divided into 2 subgroups of 12 specimens each. The specimens were either 48 h water-stored or thermocycled (6000 x 5-55 degrees C). The shear bond strengths of composite resin to FRC were measured at a crosshead speed of 1.0 mm/min. The data were analyzed by ANOVA for factors 'treatment type' and 'storage condition'; Tukey's post-hoc tests and Weibull analysis were performed. ANOVA showed a significant difference as a function of surface treatment (P<0.05) and storage condition (P<0.05). The CJ-SIL-MP group showed highest bond strength and Weibull modulus after thermocycling. Repair of multiphase polymer matrix FRC may show reliable bond strength when silane treatment is used along with air-particle abrading. [ABSTRACT FROM AUTHOR]

A systematic review of chemotherapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for the evaluation of the scientific literature are described separately (Acta Oncol 2001; 40: 155-65). This overview of the literature on chemotherapy in the treatment of gastric cancer is based on 153 scientific papers including one meta-analysis, 18 reviews, 60 randomised studies and 57 prospective studies. The trials consist of 12 367 patients. The conclusions reached can be summarized into the following points: •A meta-analysis of 21 randomised adjuvant studies revealed a statistically significant survival benefit. The Odds Ratio (OR) is 0.84 (95% confidence interval, 95% CI, 0.74-0.96). However, by analysing Western world and Asian studies separately, a statistically significant difference can be noticed; the Western world studies showed an OR of 0.96 (95% CI 0.83-1.12) and the Asian an OR of 0.58 (95% CI 0.44-0.76). The cause of this difference is not apparent. There is not sufficient evidence to recommend adjuvant chemotherapy as routine treatment in the Western world. •Preoperative chemotherapy given to patients with non-resectable tumours or locally advanced potentially resectable tumours has achieved resectability rates of 40-100% and potentially curative resections in 37-80%. One out of two randomised studies showed a significant survival benefit, but reported data are not convincing. Experimental data in favour of preoperative therapy has not yet been confirmed in randomised clinical studies. Therapy is only justified in controlled clinical trials. •Published studies on the use of intraperitoneal chemotherapy are few and not conclusive regarding the efficiency and safety. This method of drug administration is, accordingly, justified only in controlled clinical trials. •In advanced gastric cancer, phase II studies have indicated better response rates using drug combinations than using single drug regimens, differences that have not, however, been convincingly demonstrated in randomised studies. No firm conclusions can be drawn regarding the superiority for any of the studied drug combinations with respect to response or survival gain. •A statistically significant survival benefit has been shown in trials comparing drug combinations with a best supportive care arm in the treatment of advanced gastric cancer. However, the number of included patients is small. The median survival benefit in advanced disease is in the range of three to nine months. •The use of chemotherapy in advanced gastric cancer is justified in selected patients, e.g. in younger patients in good performance status, low tumour burden and no other serious medical condition after adequate information of potential gains and risks. •The influence of chemotherapy on quality of life in advanced gastric cancer has been reported in only a few studies. It appears that about 50% of the patients have a clinically relevant relief of tumour-related symptoms and thereby improved quality of life. In one study, quality-adjusted survival was estimated to a median of six months in the treated patients compared with two months in the controls. •The quality of the literature addressing chemotherapy for gastric cancer is frequently poor with few properly designed randomised trials. In a number of randomised multi-centre adjuvant studies the inclusions rates are remarkably low, which reduces the scientific value of the studies. [ABSTRACT FROM AUTHOR]

It is common practice to undertake interim analyses of accumulating survival data in a cancer clinical trial while patient entry and/or follow-up is still in progress. The purpose of making an interim analysis is to stop the trial if a convincing treatment difference can be demonstrated. The main problem with repeated significance tests is that the more often one analyses accumulating data, the greater the probability of eventually obtaining a significant result, p<0.05 say, even when there is in reality no treatment difference. To allow for repeated testing one must therefore choose a more stringent nominal significance level as a criterion for stopping the trial. Repeated significance tests are normally applied at equally spaced intervals, and the maximum number of tests is decided in advance. This paper presents and compares the properties of two simple and commonly applied strategies for undertaking interim analyses of accumulating survival data. [ABSTRACT FROM AUTHOR]