Systematic literature reviews and meta-analyses: part 6 of a series on evaluation of scientific publications

[Gerontological expert report on professionally justified individual services according to § 71 of the German Social Code Act (SGB) XII]

BACKGROUND

In the second half of 2023 the Senate for Science, Health and Nursing of Berlin commissioned an explicit gerontological expert report from the team of authors, which was intended to provide suggestions for the modernization and concretization of § 71 of the German Social Code Act (SGB) XII, i.e., the central social law basis for so-called care of older people. It was completed by the end of 2023. The objective of the report was to provide suggestions for a Berlin Assistance for Old People Structural Law that considers the differentiation and diversity of the life phase of old age by identifying, analyzing and describing the necessary individual services.

AIM OF THE ARTICLE

The approach and the central results of the report are presented and discussed.

MATERIAL AND METHODS

In a multistep procedure, combined with a multimodal research approach, various methods were combined in order to generate a comprehensive understanding of the current situation of so-called assistance for older people and gerontological justifications for its services. Critical and selective literature reviews, document analysis and qualitative guideline-based expert interviews were used.

RESULTS AND DISCUSSION

The expert report contains concrete recommendations for an age phase and life situation-orientated development of individual services according to § 71 SGB XII. This relates to approaches, forms and topics of counselling that enable and support successful ageing for all older people. The report also explicitly identifies objects of necessary cash and non-cash benefits, which, even in precarious situations in old age, aim to strengthen the ability for self-help and provide the opportunity to participate independently in community life.

Evaluation of ocular and systemic endpoints after radiation of posterior uveal melanoma - A systematic review and meta-analysis

Background

Due to the large number of radiotherapeutic options for treatment of posterior uveal melanoma (UM), advantages of each option regarding important clinical endpoints have yet to be determined. Therefore, objective of this systematic review was to analyze the numerous pro- and retrospective cohort studies focusing on the efficacy of different radiotherapeutic options for UM in adults, considering local tumor control, overall survival, visual acuity, eye preservation, metastasis, radiation side effects and dose rates.

Methods

The Review was performed based on the Cochrane Handbook of Systematic Reviews. The PubMed database was searched for studies published from January 1st, 2000, up to December 31st, 2021. Research, study selection and critical appraisal was performed by two reviewers. The risk of bias assessment was performed through the revised Cochrane risk of bias tools RoB 2 and ROBINS-I. A meta-analysis of proportions was performed using R (R version 4.1.3, library: meta, procedure: metaprop). This systematic review was registered with Prospero (ID CRD42022311758).

Results

Of 4886 studies identified in the database, a total of 20 studies with 4979 participants were included in the qualitative synthesis. Through critical appraisal with ROBINS-I and RoB 2, studies received a 'moderate', 'serious' or 'some concerns' overall risk of bias. Heterogeneity analysis allowed for meta-analysis of proportion of 3 outcome-therapy combinations: local tumor control with I-125 Brachytherapy (proportion: 0.94, CI 95 %: 0.91-0.98), local tumor control with proton therapy (proportion: 0.96, CI 95 %: 0.92-1.00) and eye preservation with I-125 brachytherapy (proportion: 0.91, CI 95 %: 0.88-0.93). This shows local tumor control to be at 94 % with I-125 brachytherapy and at 96 % with proton therapy, as well as an eye preservation rate of 91 % with I-125 brachytherapy.

Discussion

The evaluation of outcomes of radiotherapy in UM is limited because of missing data on radiation doses as well as great heterogeneity of study protocols. Radiation therapy outcomes are so far not comparable. Therefore, we recommend for upcoming studies on this topic to provide the biological effective dose (BED) or the equivalent dose in 2 Gy fractions (EQD2) per eye structure, thereby enabling a comparison of outcomes of different forms of radiation therapy.

A narrative review of Master's programs in midwifery across selected OECD countries: Organizational aspects, competence goals and learning outcomes

Shifting midwifery education to a university level is of great importance for healthcare systems worldwide by preparing graduates for current and future challenges. Some of them referring to management, research and teaching tasks as well as advanced practitioner roles, require competences that can only be acquired in a Master's program. The objectives of this narrative review are to outline the differences and commonalities of organizational aspects of Master's programs in selected OECD countries and to point out the competence goals and learning outcomes they are based on. Fifteen Master's programs in twelve OECD countries were identified and analyzed. Considering the organizational characteristics, differences are found in admission requirements and qualification levels, while similarities relate to the awarded title (MSc). All programs aim to develop abilities for research to advance midwifery practice. Leadership and management abilities are addressed through effective teamwork and communication. The programs' aims are to develop abilities for midwifery education tasks. Whereas competence goals mostly align across the programs, they are addressed differently through various learning outcomes. Development and enhancement of Master's programs in midwifery are needed by focusing on core elements, such as common competence goals. It is equally important to adapt them to national healthcare and educational systems.

Screw fixation in the treatment of displaced intra-articular calcaneus fractures: a systematic review protocol

BACKGROUND

The Calcaneus is the largest bone of the foot and the most frequent tarsal bone to be fractured. Overall, it causes round about 10 cases per 100,000 residents per year mainly in men. Especially displaced intra-articular calcaneus fractures often have early and late complications and its associated disability. There are various strategies for the treatment of displaced intra-articular calcaneus fractures, but the gold standard is still subject of a long-standing controversy. Minimally invasive procedures became more common in an attempt to reduce the high rate of complications associated with open reduction and internal fixation. With the increase in minimally invasive techniques, screw fixation also gained in significance. The current literature does not sufficiently elucidate whether the screw fixation is superior to other treatment options especially in relation to adverse events, health-related quality of life and postoperative pain. This study aims to investigate benefits and harms of treating displaced intra-articular calcaneus fractures (types II, III and IV according to Sanders) with screw fixation in adults.

METHODS

A systematic review will be conducted based on the principles described in the Cochrane Handbook. We will include adults with displaced intra-articular calcaneus fractures of Sanders type II, III and IV. The surgical method of screw fixation shall be compared to other surgical interventions to stabilise calcaneus fractures. Primary outcomes are serious adverse events, health-related quality of life and postoperative pain level. MEDLINE, CENTRAL, CINAHL, Web of Science and bibnet.org, ClinicalTrial.gov and the World Health Organization International Clinical Trials Registry Platform (ICTR) will be searched. Screening and data extraction will be performed by two authors independently. A third author will arbitrate disputes. Risk of Bias will be assessed with the Cochrane tool. Meta-analysis will be performed if participants, interventions, comparisons and outcomes are sufficiently similar to ensure a result that is clinically meaningful.

DISCUSSION

Due to the increasing use of minimally invasive techniques and the increasing use of screw fixation instead of open reduction and plate fixation, it is important to analyse the benefits and harms of screw fixation for calcaneus fractures. Screw fixation could, in the future, help to operate in a less invasive and tissue preserving manner while still achieving an adequate functional result for the patient SYSTEMATIC REVIEW REGISTRATION: CRD42021244695.

Impact of the left common ostium following pulmonary vein isolation in AF: Systematic review and meta-analysis

Purpose

Pulmonary vein isolation (PVI) through catheter ablation is the basis for the treatment of atrial fibrillation (AF). The left common ostium (LCO) is a high prevalence anatomical variation and has conflicting results in the effects on the prognosis following ablation. We undertook a systematic review and meta-analysis of studies that compared the arrhythmia recurrence rate after radiofrequency ablation or cryoablation balloon between patients with normal pattern pulmonary vein and patients with LCO.

Methods and Results

Results were pooled using a fixed or random effect, at the discretion of heterogeneity (>25%), in addition, we associated subgroup analysis in these cases and when clinically indicated. Fourteen non-randomized studies totaling 3278 patients were included. In analyses using the two energies all patients: OR 1.01 (95% CI 0.84-1.23; P = .90, I 2 = 67%) and excluding patients with any type of persistent AF (PeAF) and those submitted to linear atrial lesion (LAL) OR 0.80 (95% CI 0.52-1.22; P = .30, I 2 = 71%). Using CRYO: all patients OR 1.34 (95% CI 1.03-1.74; P = .03, I 2 = 0%). Using RF: all patients-OR 0.55 (95% CI 0.32-0.95; P = .03, I 2 = 49%); excluding studies with long duration PeAF and the performance of LAL concomitant-OR 0.45 (95% CI 0.23-0.91; P = .03, I 2 = 44%).

Conclusion

The results suggest a better prognosis in patients with LCO, submitted to PVI without additional LAL under RF energy in paroxysmal AF and short-duration PeAF. In patients undergoing CRYO, the presence of LCO suggests a worse prognosis.

How do supported employment programs work? Answers from a systematic literature review

Many studies have found that supported employment (SE) has effectively helped people with severe mental illness obtain and maintain competitive employment. However, most SE studies have asked "What works?" rather than discerning what works for whom, in what circumstances, in what respects and how. It is important to understand the outcomes of SE and identify the impact factors (contexts and mechanisms) that can trigger them. Four literature databases were searched for studies that analyzed counseling settings. Overall, 104 publications met the inclusion criteria. The review showed that most of the research on SE programs were one-dimensional, looking at either the effects of SE programs, the client or the professional, or the relationship between clients and professionals. The model reveals that impact factors are interconnected and can have a cumulative impact on the client, professionals, and the environment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10775-022-09533-3.

[Sonographic diagnosis of tonsillar abscesses: Our experience and a systematic review]

BACKGROUND

Transcutaneous sonography has been an integral part of imaging diagnostics in the head and neck region for several decades. Especially in the imaging of abscesses of the tonsillar fossa, sonography is a fast, safe, and cost-effective diagnostic method. This paper aims to provide an overview of the currently published studies in terms of diagnostic value.

MATERIAL AND METHODS

systematic literature search in the following online databases: PubMed und MEDLINE according to the search terms: transcutaneous ultrasound, tonsillar abscess, peritonsillar abscess, intratonsillar abscess, peritonsillar cellulitis, parapharyngeal abscess. Evaluation of the scientific relevance of the papers according to established criteria.

RESULTS

The publications were analyzed in terms of clinical application, clinical diagnosis, and diagnostic accuracy. Sensitivity and specificity are reported between 67 % - 100 %, and 50 % - 93 %, respectively, depending on the study and patient cohort.

CONCLUSIONS

In the synopsis of the currently published results, transcutaneous sonography promises a high potential to improve the diagnosis of peritonsillar abscess and allows a reliable differentiation to peritonsillar cellulitis. This fact seems crucial for the clinical management of patients with suspected abscesses.

The Power of Women's Faith in Coping with Intimate Partner Violence: Systematic Literature Review

Violence in an intimate partnership is a form of domestic violence where physical or psychological acts of violence are committed by a partner or spouse against another partner or spouse, and other family members may be victims as well. Its prevalence is worrisome and is not limited to any specific circumstances. It also occurs in Christian families, and research data show that the rate of intimate partner violence in Christian families is no higher or lower compared to the general incidence. That being said, religiosity combined with other factors may contribute to the vulnerability of the victim or the power of the perpetrator. On the other hand, religious values and aspects provide protection and support in preventing violence in Christian families and recovering after violence has occurred. We analysed 18 different studies on intimate partner violence in Christian families using the systematic literature review method, and in this paper, we present findings that indicate which aspects of Christian tradition and practice, in combination with other factors, provide protection and support in preventing violence and helping to recover from it for women who are the victims of violence by their intimate partners.

Bio-Psycho-Socio-Spirito-Cultural Factors of Burnout: A Systematic Narrative Review of the Literature

Background: Burnout is a widespread, multifactorial, and mainly psychological phenomenon. The pathogenesis of burnout is commonly described within the bio-psycho-social model of health and disease. Recent literature suggests that the phenomenon of burnout may be broader so that the three dimensions might not reflect the multifaceted and complex nature of the syndrome. Consequently, this review aims to identify the diversity of factors related to burnout, to define overarching categories based on these, and to clarify whether the bio-psycho-social model adequately describes the pathogenesis of burnout-holistically and sufficiently. Method: Five online databases (PubMed, PubPsych, PsychARTICLES, Psychology and Behavioral Sciences Collection, and Google Scholar) were systematically searched using defined search terms to identify relevant studies. The publication date was set between January 1981 and November 2020. Based on the selected literature, we identified factors related to burnout. We aggregated these factors into a comprehensible list and assigned them to overarching categories. Then, we assigned the factors to the dimensions of an extended model of health and disease. Results: We identified a total of 40 burnout-related factors and 10 overarching categories. Our results show that in addition to biological, psychological, and socio-environmental factors, various factors that can be assigned to a spiritual and work cultural dimension also play an important role in the onset of burnout. Conclusion: An extended bio-psycho-socio-spirito-cultural model is necessary to describe the pathogenesis of burnout. Therefore, future studies should also focus on spiritual and work cultural factors when investigating burnout. Furthermore, these factors should not be neglected in future developments of diagnosis, treatment, and prevention options.

[Are Intensified Secondary Prevention Programmes Effective Interventions to Reduce Disability-Related Early Retirement After Cardiac Rehabilitation?]

PURPOSE

We aimed to combine follow-up data from 3 randomized controlled studies to evaluate the effectiveness of intensified (telephone-based) secondary prevention programmes on disability-related early retirement.

METHODS

Each trial (SeKoNa, Sinko and OptiHyp) compared an intensified (telephone-based) secondary prevention concept as an intervention to an untreated control group (standard management). We extracted extensive baseline data on sociodemographic, clinical and diagnostic characteristics on an individual patient level from the original trial data sets. Follow-up analysis is based on routine data of the German Pension Insurance Rhineland (obtained in August 2019). The primary outcome parameters are mortality (all causes), recurrent cardiac events, and employment status three years after rehabilitation. Here we report results regarding disability-related early retirement. Outcome data were pooled with via meta-analysis for individual patient data (Individual Patient Data Meta-Analysis IPD-MA) using classical meta-analytical techniques (one-stage approach using mixed models and 2-stage approach with inverse variance estimation as fixed effects model).

RESULTS

A total of 1058 cardiac rehabilitation patients were included in the analyses. There were no differences between the pooled intervention group (n=499) and the pooled control group (n=559) regarding any baseline parameter at discharge after 3-week cardiac rehabilitation. There are no indications of statistical heterogeneity. In the total sample incident disability-related early retirement rate was 11.8% at 3-year follow-up. Participation in an intensified secondary prevention programme reduced the risk by about 60% compared to the control group (OR: 0.43; 95% CI: 0.36-0.51).

CONCLUSION

The need for effective rehabilitation programmes is rapidly growing due to the current demographic trend with an increase in ageing working populations. Secondary prevention programmes following 3-week inpatient rehabilitation are an effective tool to sustainably support the prevention of health-related premature reduction in earning capacity pensions and therefore should complement the existing rehabilitation offer. Based on our results we conclude that secondary prevention should be provided long enough (at least one year) and in personal contact.

Status of Telemonitoring Services in Diabetes Care in Germany: A Narrative Review

Background

Diabetes mellitus (DM) as a chronic disease is a great medical, organizational, and financial burden on the German healthcare system, and it has risen in epidemiological importance. To ensure healthcare against the background of rising prevalence rates and to reduce costs, it makes sense to supplement treatment of diabetes patients with telemedical services.

Objectives

The aim was to evaluate telemonitoring services for DM patients in Germany and the political/legal environment.

Materials and Methods

A narrative review was conducted to provide a comprehensive and critical analysis of the current knowledge on interactive telemonitoring offerings and influencing factors. A total of 19 publications were considered as relevant in the screening process, and were included in the content analysis.

Results

The results can be differentiated in terms of political/legal requirements, needs, and supply-related aspects. Only four studies focused on the individual care aspects of telemedical care of DM patients.

Conclusion

Telemonitoring measures for chronic diseases in general and for DM in particular have hardly been implemented in Germany so far. Based on the deficiencies and research gaps described earlier, some recommendations can be made. There is a need to set up structure for more interactivity, to expand technical infrastructure, and to close legal gaps. More research focusing on clinical effectiveness is necessary.

A Meta-Analysis of the Effects of Insects in Feed on Poultry Growth Performances

Simple Summary

Today, insects are receiving great attention as a potential source of poultry feed and the number of experiences is exploding. However, it is difficult to obtain an evidence-based view from this large volume of and large diversity of information. A meta-analysis is the best method to summarize the findings of all these studies. Thus, we searched all recent studies that explore the effects of insects in feed on the growth performances of poultry species. Results showed that insects in feed do not modify performances if they substitute less than 10% of conventional protein sources and are not grasshoppers.

Abstract

We investigated and summarized results from studies evaluating the effects of feeding poultry with insects on their growth performances. After a systematic review of studies published since 2000, two independent reviewers assessed the eligibility of each one based on predefined inclusion criteria. We extracted information on the study design, insects, avian species, and growth performances, i.e., average daily gain, feed intake, and feed conversion ratio. Next, we estimated pooled differences between performances of poultry fed a diet with vs. without insects through random-effects meta-analysis models. Additionally, these models evaluated the effects of potential sources of heterogeneity across studies. Of the 75 studies reviewed, 41 met the inclusion criteria and included 174 trials. With respect to diets without insects, pooled differences in growth performances were statistically not different from the null, but heterogeneity was marked across studies. Average daily gain decreased with increasing inclusion rates of insects, going below the null for rates of 10% and more. Grasshoppers were negatively associated with the average daily gain and positively associated with feed intake. The country of publication was another source of heterogeneity across publications. Overall, our results show insects should substitute only partially conventional protein sources and not be grasshoppers to guarantee the appropriate growth of birds.

Evaluation of new quality indicators for the TraumaRegister DGU® using the systematic QUALIFY methodology

BACKGROUND

The TraumaRegister DGU^® (TR-DGU) of the German Trauma Society (Deutsche Gesellschaft für Unfallchirurgie, DGU) enables the participating hospitals to perform quality management. For that purpose, nine so-called audit filters have existed, since its foundation, which, inter alia, is listed in the Annual Report. The objective of this study effort is a revision of these quality indicators with the aim of developing pertinent new and reliable quality indicators for the management of severely injured patients.

MATERIALS AND METHODS

Apart from indicators already used at national and international levels, a systematic review of the literature revealed further potential key figures for quality of the management of severely injured patients. The latter were evaluated by an interdisciplinary and interprofessional group of experts using a standardized QUALIFY process to assess their suitability as a quality indicator.

RESULTS

By means of the review of the literature, 39 potential indicators could be identified. 9 and 14 indicators, respectively, were identified in existing trauma registries (TR-DGU and TARN), 17 in the ATLS^® training concept, and 57 in the S3 guideline on the treatment of polytrauma/severe injuries. The exclusion of duplicates and the limitation to indicators that can be collected using the TR-DGU Version 2015 data set resulted in a total of 43 indicators to be reviewed. For each of the 43 indicators, 13 quality criteria were assessed. A consensus was achieved in 305 out of 559 individual assessments. With 13 quality criteria assessed and 43 indicators correspond this to a relative consensus value of 54.6%. None of the indicators achieved a consensus in all 13 quality criteria assessed. The following 13 indicators achieved a consensus in at least 9 quality criteria: time between hospital admission and WBCT, mortality, administration of tranexamic acid to bleeding patients, use of CCT with GCS <14, time until first emergency surgical intervention (7-item list in the TR-DGU), time until surgical intervention for penetrating trauma, application of pelvic sling belt (prehospital), capnometry (etCO₂) in intubated patients, time until CCT with GCS < 15, time until surgery for hemorrhagic shock, time until craniotomy for severe TBI, prehospital airway management in unconscious patients (GCS < 9), and complete basic diagnostics available. Two indicators achieved a consensus in 11 criteria and thus represent the maximum consensus achieved within the group of experts. Four indicators only achieved a consensus in three quality criteria. 17 indicators had a mean value for the 3 relevance criteria of ≥ 3.5 and were, therefore, assessed by the group of experts as being highly relevant.

CONCLUSION

Not all the key figures published for the management of severely injured patients are suitable for use as quality indicators. It remains to be seen whether the quality indicators identified by experts using the QUALIFY process will meet the requirements in practice. Prior to the implementation of the assessed quality indicators in standardized quality assurance programs, a scientific evaluation based on national data will be required.

[Low level laser therapy : A narrative literature review on the efficacy in the treatment of rheumatic orthopaedic conditions]

BACKGROUND

In low level laser therapy (LLLT) low wattage lasers are used to irradiate the affected skin areas, joints, nerves, muscles and tendons without any sensation or thermal damage. Although the exact mechanism of its effect is still unknown, it seems beyond dispute that LLLT induces a variety of stimulating processes at the cellular level affecting cell repair mechanisms, the vascular system and lymphatic system. LLLT has been popular among orthopaedic practitioners for many years, whereas university medicine has remained rather sceptical about it.

OBJECTIVES

Overview of studies on the efficacy of LLLT in the treatment of rheumatic orthopaedic conditions, i. e. muscle, tendon lesions and arthropathies.

MATERIALS AND METHODS

Narrative literature review (PubMed, Web of Science).

RESULTS

While earlier studies often failed to demonstrate the efficacy of LLLT, several recent studies of increasing quality proved the efficacy of LLLT in the treatment of multiple musculoskeletal pain syndromes like neck or lower back pain, tendinopathies (especially of the Achilles tendon) and epicondylolpathies, chronic inflammatory joint disorders like rheumatoid arthritis or chronic degenerative osteoarthritis of the large and small joints. In addition, there is recent evidence that LLLT can have a preventive capacity and can enhance muscle strength and accelerate muscle regeneration.

CONCLUSION

LLLT shows potential as an effective, noninvasive, safe and cost-efficient means to treat and prevent a variety of acute and chronic musculoskeletal conditions. Further randomized controlled studies, however, are required to confirm this positive assessment.

Disease-Modifying Therapies for Multiple Sclerosis: A Systematic Literature Review of Cost-Effectiveness Studies

INTRODUCTION AND OBJECTIVE

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. MS is considered incurable; however, disease treatment has advanced significantly over the past several decades with the introduction of disease-modifying therapies (DMTs). The current study reviewed the cost-effectiveness analyses of DMTs in relapsing-remitting MS (RRMS) patients.

METHODS

A systematic literature search of bibliographic databases was conducted to identify economic evaluations published after 2007. The relevant population, intervention, comparators, outcomes, and study design (PICOS) were considered. The outcomes of interest were incremental cost-effectiveness ratios (ICERs), net monetary benefits, incremental benefits, and incremental costs. The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement was used to assess the reporting quality of published studies.

RESULTS

A total of 1370 potentially relevant citations were identified, of which 33 published articles and four Health Technology Assessment (HTA) reports prepared for the UK were included in the final analysis. Almost all studies were based on a health economic model and considered RRMS as the phase of disease at study entry. The studies were conducted in 10 different countries, with approximately 50% based in the US. Study outcomes were rarely comparable due to the different settings, input data, and assumptions. Even within the same country, the discrepancy between study criteria was considerable. The compliance with reporting standards of the CHEERS statement was generally high.

CONCLUSIONS

Internationally, a large number of health economic assessments of DMTs in RRMS were available, yielding difficult to compare, and at times conflicting, results.

A 'meta-analysis' of effects of post-hatch food and water deprivation on development, performance and welfare of chickens

A 'meta-analysis' was performed to determine effects of post-hatch food and water deprivation (PHFWD) on chicken development, performance and welfare (including health). Two types of meta-analysis were performed on peer-reviewed scientific publications: a quantitative 'meta-analysis' (MA) and a qualitative analysis (QA). Previously reported effects of PHFWD were quantified in the MA, for variables related to performance, mortality and relative yolk sac weight. The QA counted the number of studies reporting (non-)significant effects when five or more records were available in the data set (i.e. relative heart, liver and pancreas weight; plasma T3, T4 and glucose concentrations; relative duodenum, jejunum and ileum weight; duodenum, jejunum and ileum length; and villus height and crypt depth in duodenum, jejunum and ileum). MA results indicated that 24 hours of PHFWD (i.e. ≥12-36 hours) or more resulted in significantly lower body weights compared to early-fed chickens up to six weeks of age. Body weights and food intake were more reduced as durations of PHFWD (24, 48, 72, ≥84 hours) increased. Feed conversion rate increased in chickens up to 21 and 42 days of age after ≥84 hours PHFWD in comparison with chickens fed earlier. Total mortality at day 42 was higher in chickens after 48 hours PHFWD compared to early fed chickens or chickens after 24 hours PHFWD. First week mortality was higher in chickens after ≥84 hours PHFWD than in early fed chickens. The MA for relative yolk sac weight was inconclusive for PHFWD. The QA for plasma T3, T4 and glucose concentrations indicated mainly short-term decreases in T3 and glucose in PHFWD chickens compared to early fed chickens, and no effects of PHFWD on T4 concentrations. Relative weights of liver, pancreas and heart were lower after PHFWD, but only in the first week of life. A retarded development of gut segments (duodenum, jejunum and ileum) was found in the first week of life, measured as shorter, lower relative weight, and lower villus height and crypt depth. It is concluded that 48 hours (≥36-60 hours) PHFWD leads to lower body weights and higher total mortality in chickens up to six weeks of age, the latter suggesting compromised chicken welfare, but effects of PHFWD on organ development and physiological status appear to be mainly short-term.

Indirect Comparisons and Network Meta-Analyses

BACKGROUND

Systematic reviews provide a structured summary of the results of trials that have been carried out on any particular subject. If the data from multiple trials are sufficiently homogenous, a meta-analysis can be performed to calculate pooled effect estimates. Traditional meta-analysis involves groups of trials that compare the same two interventions directly (head to head). Lately, however, indirect comparisons and network metaanalyses have become increasingly common.

METHODS

Various methods of indirect comparison and network meta-analysis are presented and discussed on the basis of a selective review of the literature. The main assumptions and requirements of these methods are described, and a checklist is provided as an aid to the evaluation of published indirect comparisons and network meta-analyses.

RESULTS

When no head-to-head trials of two interventions are available, indirect comparisons and network metaanalyses enable the estimation of effects as well as the simultaneous analysis of networks involving more than two interventions. Network meta-analyses and indirect comparisons can only be useful if the trial or patient characteristics are similar and the observed effects are sufficiently homogeneous. Moreover, there should be no major discrepancy between the direct and indirect evidence. If trials are available that compare each of two treatments against a third one, but not against each other, then the third intervention can be used as a common comparator to enable a comparison of the other two.

CONCLUSION

Indirect comparisons and network metaanalyses are an important further development of traditional meta-analysis. Clear and detailed documentation is needed so that findings obtained by these new methods can be reliably judged.

Maternal supplementation with folic acid and other vitamins and risk of leukemia in offspring: a Childhood Leukemia International Consortium study

BACKGROUND

Maternal prenatal supplementation with folic acid and other vitamins has been inconsistently associated with a reduced risk of childhood acute lymphoblastic leukemia (ALL). Little is known regarding the association with acute myeloid leukemia (AML), a rarer subtype.

METHODS

We obtained original data on prenatal use of folic acid and vitamins from 12 case-control studies participating in the Childhood Leukemia International Consortium (enrollment period: 1980-2012), including 6,963 cases of ALL, 585 cases of AML, and 11,635 controls. Logistic regression was used to estimate pooled odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for child's age, sex, ethnicity, parental education, and study center.

RESULTS

Maternal supplements taken any time before conception or during pregnancy were associated with a reduced risk of childhood ALL; odds ratios were 0.85 (95% CI = 0.78-0.92) for vitamin use and 0.80 (0.71-0.89) for folic acid use. The reduced risk was more pronounced in children whose parents' education was below the highest category. The analyses for AML led to somewhat unstable estimates; ORs were 0.92 (0.75-1.14) and 0.68 (0.48-0.96) for prenatal vitamins and folic acid, respectively. There was no strong evidence that risks of either types of leukemia varied by period of supplementation (preconception, pregnancy, or trimester).

CONCLUSIONS

Our results, based on the largest number of childhood leukemia cases to date, suggest that maternal prenatal use of vitamins and folic acid reduces the risk of both ALL and AML and that the observed association with ALL varied by parental education, a surrogate for lifestyle and sociodemographic characteristics.

Research across the disciplines: a road map for quality criteria in empirical ethics research

BACKGROUND

Research in the field of Empirical Ethics (EE) uses a broad variety of empirical methodologies, such as surveys, interviews and observation, developed in disciplines such as sociology, anthropology, and psychology. Whereas these empirical disciplines see themselves as purely descriptive, EE also aims at normative reflection. Currently there is literature about the quality of empirical research in ethics, but little or no reflection on specific methodological aspects that must be considered when conducting interdisciplinary empirical ethics. Furthermore, poor methodology in an EE study results in misleading ethical analyses, evaluations or recommendations. This not only deprives the study of scientific and social value, but also risks ethical misjudgement.

DISCUSSION

While empirical and normative-ethical research projects have quality criteria in their own right, we focus on the specific quality criteria for EE research. We develop a tentative list of quality criteria--a "road map"--tailored to interdisciplinary research in EE, to guide assessments of research quality. These quality criteria fall into the categories of primary research question, theoretical framework and methods, relevance, interdisciplinary research practice and research ethics and scientific ethos.

SUMMARY

EE research is an important and innovative development in bioethics. However, a lack of standards has led to concerns about and even rejection of EE by various scholars. Our suggested orientation list of criteria, presented in the form of reflective questions, cannot be considered definitive, but serves as a tool to provoke systematic reflection during the planning and composition of an EE research study. These criteria need to be tested in different EE research settings and further refined.

The occupational risk of Helicobacter pylori infection among gastroenterologists and their assistants

BACKGROUND

Helicobacter pylori is a widely spread bacterium that mainly inhabits the gastric mucosa and can lead to serious illnesses such as peptic ulcer disease, gastric carcinoma and gastric MALT lymphoma. The oral-oral route seems to be the main transmission route. The fact that endoscopes are contaminated after being used to perform a gastroscopy leads one to question whether gastroenterologists and endoscopy nurses and assistants run a higher risk of infection.

METHODS

A systematic search for literature was conducted in the MEDLINE and EMBASE databases and further publications were found in reference lists of relevant articles. Epidemiological studies on the occupational exposure of endoscopy personnel were collected and their quality was assessed. Pooled effect estimates were identified in a meta-analysis.

RESULTS

Of the 24 studies included in the analysis, 15 were considered to be methodologically good. Of these 15 studies, eight single studies showed a statistically significant increased risk of infection for gastroenterologists, and five for their assistants. Meta-analysis across all methodologically good studies found a statistically significant risk of 1.6 (95%CI 1.3-2.0) for doctors. The pooled effect estimates also indicated a statistically significant risk of Helicobacter pylori infection (RR 1.4; 95%CI 1.1-1.8) for assistants too.When studies are stratified by medical and non-medical control groups, statistically significant risks can only be recognised in the comparison with non-medical controls.

CONCLUSIONS

In summary, our results demonstrated an increased risk of Helicobacter pylori infection among gastroenterological personnel. However, the choice of control group is important for making a valid assessment of occupational exposure risks.

The financing of drug trials by pharmaceutical companies and its consequences. Part 1: a qualitative, systematic review of the literature on possible influences on the findings, protocols, and quality of drug trials

BACKGROUND

In recent years, a number of studies have shown that clinical drug trials financed by pharmaceutical companies yield favorable results for company products more often than independent trials do. Moreover, pharmaceutical companies have been found to influence drug trials in various ways. This paper provides an overview of the findings of current, systematic studies on this topic.

METHODS

Publications retrieved from a systematic Medline search on this topic from 1 November 2002 to 16 December 2009 were independently evaluated and selected by two of the authors. These publications were supplemented by further ones found in their references sections.

RESULTS

57 publications were included for evaluation in Parts 1 and 2 of this article. Published drug trials that were financed by pharmaceutical companies, or whose authors declared a financial conflict of interest, were found to yield favorable results for the drug manufacturer more frequently than independently financed trials whose authors had no such conflicts. The results were also interpreted favorably more often than in independently financed trials. Furthermore, there was evidence that pharmaceutical companies influenced study protocols in a way that was favorable to themselves. The methodological quality of trials financed by pharmaceutical companies was not found to be any worse than that of trials financed in other ways.

CONCLUSION

Published drug trials that are financed by pharmaceutical companies may present a distorted picture. This cannot be explained by any difference in methodological quality between such trials and trials financed in other ways.