Discussing study limitations in reports of biomedical studies- the need for more transparency

'Spin' in urology non-randomised studies comparing therapeutic interventions: a temporal analysis

OBJECTIVE

To determine the prevalence of 'spin' (i.e., reporting practices that distort the interpretation of results by positively reflecting negative findings or downplaying potential harms) strategies and level of spin in urological observational studies and whether the use of spin has changed over time.

MATERIALS AND METHODS

MEDLINE and Embase were searched to identify observational studies comparing therapeutic interventions in the top five urology journals and major urological subspecialty journals, published between 2000 and 2001, 2010 and 2011, and 2020 and 2021.

RESULTS

A total of 235 studies were included. Spin was identified in 81% of studies, with a median of two strategies per study. The most commonly used strategies were inadequate implication for clinical practice (30%), causal language or causal claim (29%), and use of linguistic spin (29%). Moderate to high levels of spin were found in 55% of conclusions. From 2000 to 2020, the average number of strategies used has significantly decreased each decade (H = 27.459, P < 0.001), and the median level of spin in conclusions was significantly lower in studies published in the 2020s and 2010s than in the 2000s (H = 11.649, P = 0.003).

CONCLUSIONS

Our results suggest that 81% of urological observational studies comparing therapeutic interventions contained spin. Over the past two decades, the use of spin has significantly declined, but this remains an area for improvement, with 70% of included studies published in the 2020s employing spin. Medical writing should scrupulously avoid words or phrases that are not supported by data in the manuscript.

Automatic categorization of self-acknowledged limitations in randomized controlled trial publications

OBJECTIVE

Acknowledging study limitations in a scientific publication is a crucial element in scientific transparency and progress. However, limitation reporting is often inadequate. Natural language processing (NLP) methods could support automated reporting checks, improving research transparency. In this study, our objective was to develop a dataset and NLP methods to detect and categorize self-acknowledged limitations (e.g., sample size, blinding) reported in randomized controlled trial (RCT) publications.

METHODS

We created a data model of limitation types in RCT studies and annotated a corpus of 200 full-text RCT publications using this data model. We fine-tuned BERT-based sentence classification models to recognize the limitation sentences and their types. To address the small size of the annotated corpus, we experimented with data augmentation approaches, including Easy Data Augmentation (EDA) and Prompt-Based Data Augmentation (PromDA). We applied the best-performing model to a set of about 12K RCT publications to characterize self-acknowledged limitations at larger scale.

RESULTS

Our data model consists of 15 categories and 24 sub-categories (e.g., Population and its sub-category DiagnosticCriteria). We annotated 1090 instances of limitation types in 952 sentences (4.8 limitation sentences and 5.5 limitation types per article). A fine-tuned PubMedBERT model for limitation sentence classification improved upon our earlier model by about 1.5 absolute percentage points in F1 score (0.821 vs. 0.8) with statistical significance (p<.001). Our best-performing limitation type classification model, PubMedBERT fine-tuning with PromDA (Output View), achieved an F1 score of 0.7, improving upon the vanilla PubMedBERT model by 2.7 percentage points, with statistical significance (p<.001).

CONCLUSION

The model could support automated screening tools which can be used by journals to draw the authors' attention to reporting issues. Automatic extraction of limitations from RCT publications could benefit peer review and evidence synthesis, and support advanced methods to search and aggregate the evidence from the clinical trial literature.

Limitations in Medical Research: Recognition, Influence, and Warning

Background

As the number of limitations increases in a medical research article, their consequences multiply and the validity of findings decreases. How often do limitations occur in a medical article? What are the implications of limitation interaction? How often are the conclusions hedged in their explanation?

Objective

To identify the number, type, and frequency of limitations and words used to describe conclusion(s) in medical research articles.

Methods

Search, analysis, and evaluation of open access research articles from 2021 and 2022 from the Journal of the Society of Laparoscopic and Robotic Surgery and 2022 Surgical Endoscopy for type(s) of limitation(s) admitted to by author(s) and the number of times they occurred. Limitations not admitted to were found, obvious, and not claimed. An automated text analysis was performed for hedging words in conclusion statements. A limitation index score is proposed to gauge the validity of statements and conclusions as the number of limitations increases.

Results

A total of 298 articles were reviewed and analyzed, finding 1,764 limitations. Four articles had no limitations. The average was between 3.7% and 6.9% per article. Hedging, weasel words and words of estimative probability description was found in 95.6% of the conclusions.

Conclusions

Limitations and their number matter. The greater the number of limitations and ramifications of their effects, the more outcomes and conclusions are affected. Wording ambiguity using hedging or weasel words shows that limitations affect the uncertainty of claims. The limitation index scoring method shows the diminished validity of finding(s) and conclusion(s).

The reporting of study limitations in randomized controlled trials published in the leading dental journals: Is it sufficient?

OBJECTIVES

Adequate reporting of limitations is crucial to enable clinicians to accurately interpret the clinical trial findings. This meta-epidemiological study aimed to evaluate whether study limitations are reported in full-text articles of randomized controlled trials (RCTs) published in the leading dental journals. Associations between the trial characteristics and the reporting of limitations were also explored.

METHODS

RCTs published between 1st January and 31st December in the years 2011, 2016 and 2021 were identified from the 12 high impact factor dental journals (general and specialty). RCT characteristics were extracted, and reporting of limitations was recorded for the selected studies. Descriptive statistics were calculated for trial and limitations related characteristics. Univariable ordinal logistic regression models were fit to explore univariable associations between trial characteristics and reporting of limitations.

RESULTS

Two hundred and sixty-seven trials were included and analyzed. Most RCTs were published in 2021 (40.8%), had authors based in Europe (50.2%), did not have a statistician involved (88.8%) and assessed a procedure/method intervention type (40.5%). The reporting of trial limitations was generally sub-optimal. More recent trials and studies with a published protocol were associated with better reporting of limitations. The type of journal was a significant predictor for limitation reporting.

CONCLUSIONS

Within this study, the clear reporting of study limitations in the manuscripts of dental RCTs is sub-optimal and requires improvement.

CLINICAL SIGNIFICANCE

The reporting of limitations should not be viewed as a weakness of a trial but due diligence, so clinicians can fully interpret the impact of these limitations on both the validity and generalisability of the results.

The standards of reporting trials in pets (PetSORT): Explanation and elaboration

Well-designed randomized controlled trials (RCTs) provide the best evidence of the primary research designs for evaluating the effectiveness of interventions. However, if RCTs are incompletely reported, the methodological rigor with which they were conducted cannot be reliably evaluated and it may not be possible to replicate the intervention. Missing information also may limit the reader's ability to evaluate the external validity of a trial. Reporting guidelines are available for clinical trials in human healthcare (CONSORT), livestock populations (REFLECT), and preclinical experimental research involving animals (ARRIVE 2.0). The PetSORT guidelines complement these existing guidelines, providing recommendations for reporting controlled trials in pet dogs and cats. The rationale and scientific background are explained for each of the 25 items in the PetSORT reporting recommendations checklist, with examples from well-reported trials.

Development, explanation, and presentation of the Physical Literacy Interventions Reporting Template (PLIRT)

BACKGROUND

The physical literacy (PL) concept integrates different personal (e.g., physical, cognitive, psychological/affective, social) determinants of physical activity and has received growing attention recently. Although practical efforts increasingly adopt PL as a guiding concept, latest evidence has shown that PL interventions often lack specification of important theoretical foundations and basic delivery information. Therefore, the goal of the present study was to develop an expert-based template that supports researchers and practitioners in planning and reporting PL interventions.

METHODS

The development process was informed by Moher et al.'s guidance for the development of research reporting guidelines. We composed a group of ten distinguished experts on PL. In two face-to-face meetings, the group first discussed a literature-driven draft of reporting items. In the second stage, the experts anonymously voted and commented on the items in two rounds (each leading to revisions) until consensus was reached.

RESULTS

The panel recommended that stakeholders of PL initiatives should tightly interlock interventional aspects with PL theory while ensuring consistency throughout all stages of intervention development. The Physical Literacy Interventions Reporting Template (PLIRT) encompasses a total of 14 items (two additional items for mixed-methods studies) in six different sections: title (one item), background and definition (three items), assessment (one item each for quantitative and qualitative studies), design and content (five items), evaluation (one item plus one item each for quantitative and qualitative studies), discussion and conclusion (two items).

CONCLUSION

The PLIRT was designed to facilitate improved transparency and interpretability in reports on PL interventions. The template has the potential to close gaps between theory and practice, thereby contributing to more holistic interventions for the fields of physical education, sport, and health.

Examining trends in the evidence base for the treatment of burns and a quality assessment of randomised controlled trials over an 11-year period

BACKGROUND

Previous articles assessed the evidence-base for the treatment of burns, but the latest was published in 2010, examining data up to and inclusive of 2008. The aim of this article is to examine the trend in the number of high-evidence publications over the subsequent 11-year period and quality-assess RCTs within this timeframe.

MATERIALS AND METHODS

All articles published in Burns and Journal of Burn Care and Research (JBCR) were identified using PubMed Search Tools and its Single Citation Matcher function. These journals were manually screened from 01/01/2009-01/06/2020 inclusive. Additionally, a PubMed search was conducted searching for RCTs and meta-analyses in English with the MESH term burns to identify meta-analyses and RCTs in all other journals. The reporting of RCTs was assessed using a modified CONsolidated Standards of Reporting Trials (CONSORT) checklist.

RESULTS

A total of 5145 articles were evaluated from Burns and JBCR, with 3230 (62.78%) from Burns and 1915 (37.22%) from JBCR. 0.012% were meta-analyses of RCTs, 0.30% were other meta-analyses, and 2.52% were initially identified as RCTs. Whilst a significant increase in the number of high-evidence publications is observed, these represent 2.83% (n = 237) of the total. An additional 95 RCTs were identified in other journals, 58 being included in quality-analysis. A total 128 RCTs were thus eligible for quality-assessment, the most popular individual topic being wound healing (n = 28; 21.88%). The most highly reported criterion was listed inclusion and exclusion criteria (n = 111; 86.72%) and the least reported criterion was allocation concealment (n = 22; 13.92%).

CONCLUSIONS

This study observes a positive trend in high-evidence publications. The reporting of several CONSORT criteria in RCTs remains poor. Observation to standard reporting guidelines is advocated to improve the quality of reporting.

A comparative assessment of the dentoskeletal effects of clear aligners vs miniplate-supported posterior intrusion with fixed appliances in adult patients with anterior open bite. A multicenter, retrospective cohort study

INTRODUCTION

This study aimed to retrospectively evaluate the dentoskeletal effects of clear aligners (Invisalign) vs miniplate-supported posterior intrusion (MSPI) and identify factors associated with posttreatment overbite in adults with anterior open bite.

METHODS

Twenty-nine patients treated with Invisalign and 24 with MSPI combined with full-fixed orthodontic appliances were included from 5 orthodontic practices. Pretreatment and posttreatment lateral cephalometric measurements were included as outcomes. Comparisons across groups and identification of final overbite predictors were assessed with regression modeling and machine learning techniques.

RESULTS

MSPI induced significantly greater maxillary molar intrusion (1.5 mm; 95% confidence interval [CI], 0.83-2.17; P <0.001), with subsequent reduction of anterior face height (ANS-Me) (-2.77 mm; 95% CI, -3.64 to -1.91; P <0.001), Mp-SN° (-1.95°; 95% CI, -2.77 to -1.12; P <0.001), and ANB° (-1.69°; 95% CI, -2.44 to -0.94; P <0.001) compared with Invisalign. MSPI resulted in a significantly larger increase in SNB° (0.94°; 95% CI, 0.23-1.65; P = 0.01) and point-Pog projection (2.45 mm; 95% CI, 1.12-3.77; P = 0.001). Compared with MSPI, Invisalign had a significantly greater increase in the distance of maxillary (1.05 mm; 95% CI, 0.38-1.72; P = 0.003) and mandibular (0.9 mm; 95% CI, 0.19-1.60; P = 0.01) incisal edges relative to their apical bases, with borderline greater lingual tipping of only the maxillary incisors (2.82°; 95% CI, -0.44 to 6.09; P = 0.09). Appliance type and initial overbite were significant final overbite predictors across all models. However, this difference was only evident in male patients (males [1.65; 95% CI, 0.99-2.32; P <0.001]; female [-0.04; 95% CI, -0.52 to 0.44; P = 0.87]).

CONCLUSIONS

Both appliances effectively improve overbite. MSPI applied the correction via molar intrusion and counterclockwise mandibular autorotation, whereas Invisalign via maxillary and mandibular incisor extrusion.

Protein-saliva interactions: a systematic review

Food industries are challenged to reformulate foods and beverages with higher protein contents to lower fat and sugar content. However, increasing protein concentration can reduce sensory acceptability due to astringency perception. Since the properties of food-saliva mixtures govern mouthfeel perception, understanding how saliva and protein interact is key to guide development of future protein-rich reformulations with optimal sensory attributes. Hence, this systematic review investigated protein-saliva interaction using both model and real human saliva, including a quality assessment. A literature search of five databases (Medline, Pubmed, Embase, Scopus and Web of Science) was undertaken covering the last 20 years, yielding 36 604 articles. Using pre-defined criteria, this was reduced to a set of 33 articles with bulk protein solutions (n = 17), protein-stabilized emulsions (n = 13) and protein-rich food systems (n = 4). Interaction of dairy proteins, lysozyme and gelatine with model or human saliva dominated the literature. The pH was shown to have a strong effect on electrostatic interaction of proteins with negatively-charged salivary mucins, with greater interactions occurring below the isoelectric point of proteins. The effect of protein concentration was unclear due to the limited range of concentrations being studied. Most studies employed a 1 : 1 w/w protein : saliva ratio, which is not representative of true oral conditions. The interaction between protein and saliva appears to affect mouthfeel through aggregation and increased friction. The searches identified a gap in research on plant proteins. Accurate simulation of in vivo oral conditions should clarify understanding of protein-saliva interaction and its influence on sensory perception.

Biomarkers associated with periodontitis and peri-implantitis: a systematic review

Purpose

The pathology of peri-implantitis is still not fully understood and there have been recent challenges to the consensus on its aetiology and pathology, especially in comparison with periodontitis. The assessment of biomarkers allows a comparison of the pathology of these diseases. The aim of this systematic review was to answer the research question: “Is there a difference in the biomarkers associated with peri-implantitis compared with periodontitis in adult humans?”

Methods

Electronic databases were searched and screened, and a manual search was also undertaken. The inclusion criteria were adults with peri-implantitis who had been compared to adults with periodontitis with the outcome of biomarkers assessed via biopsies or crevicular fluid samples in primary or secondary care settings, as recorded in case-control, case series and retrospective, prospective and cross-sectional observational studies. Two reviewers independently screened titles and abstracts and assessed full text articles for eligibility and inclusion. Both reviewers independently extracted data and assessed risk of bias. Differences in biomarker levels were the primary outcome and a narrative review was undertaken due to the heterogeneity of studies.

Results

In total, 2,374 articles were identified in the search, of which 111 full-text articles were assessed for eligibility and 13 were included in the qualitative synthesis. Five of the 13 included studies were deemed to be at high risk of bias, with the others having moderate risk. All studies were cross-sectional and performed at university hospitals. Nine of the 13 included studies found significant differences in the levels of biomarkers or their ratios between peri-implantitis and periodontitis. Four of the studies found no significant differences.

Conclusions

Within the limitations of the included studies, it appears that there may be a difference in biomarker levels and ratios between peri-implantitis and periodontitis, suggesting that these disease processes are somewhat distinct.

Compliance With Standards for STARD 2015 Reporting Recommendations in Pathology

OBJECTIVES

Lack of experimental reproducibility has led to growing interest in guidelines to enhance completeness and transparency in research reporting. This retrospective survey sought to determine compliance with Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 statement in the recent pathology scientific literature.

METHODS

Two raters independently scored 171 pathology diagnostic accuracy studies for compliance with 34 STARD items and subcomponents. Overall adherence was calculated as a proportion after excluding nonapplicable items.

RESULTS

After excluding nonapplicable items, there was 50% overall adherence to STARD reporting recommendations. In total, 15.44 ± 3.59 items were reported per article (range, 4-28 out of maximum possible of 34). There was substantial heterogeneity in individual item reporting, with greater than 75% reporting in eight of 34 items and less than 25% reporting in 11 of 34 items. Less than 10% of articles reported hypotheses, subgroup analyses for confounding, sample size calculations, subject flow diagrams, study registrations, and links to full study protocols. Significantly more items were reported in articles from journals that endorsed STARD (16.14 vs 14.84, P = .0175).

CONCLUSIONS

These findings demonstrate incomplete reporting of essential items in pathology diagnostic accuracy studies. More vigorous enforcement of reporting checklists might improve adherence to minimum reporting standards.

Sample size, study length, and inadequate controls were the most common self-acknowledged limitations in manual therapy trials: A methodological review

OBJECTIVES

The aim of this study was to quantify and analyze the presence and type of self-acknowledged limitations (SALs) in a sample of manual therapy (MT) randomized controlled trials.

STUDY DESIGN AND SETTING

We randomly selected 120 MT trials. We extracted data related to SALs from the original reports and classified them into 12 categories. After data extraction, specific limitations within each category were identified. A descriptive analysis was performed using frequencies and percentages for qualitative variables.

RESULTS

The number of SALs per trial article ranged from 0 to 8, and more than two-thirds of trials acknowledged at least two different limitations. Despite its small proportion, 9% of trials did not report SALs. The most common limitation declared, in almost half of our sample, related to sample size (47.5%) followed by limitations related to study length and follow-up (33.3%) and inadequate controls (32.5%).

CONCLUSION

Our results indicate that at least two different limitations are consistently acknowledged in MT trial reports, the most common being those related to sample size, study length, follow-up, and inadequate controls. Analysis of the reasons behind the SALs gives some insights about the main difficulties in conducting research in this field and may help develop strategies to improve future research.

HPV vaccination and Native Americans: protocol for a systematic review of factors associated with HPV vaccine uptake among American Indians and Alaska Natives in the USA

INTRODUCTION

The nine-valent human papillomavirus (HPV) vaccine could prevent an estimated 92% of the cancers attributable to HPV types targeted by the vaccine. However, uptake of the HPV vaccine among American Indian and Alaska Native (AI/AN) adolescents has been low. AI/ANs also bear a disproportionate burden of cervical and other HPV-associated cancers. Increasing HPV vaccination rates is a national priority, but reviews and national surveys on HPV vaccination factors are lacking for the AI/AN population. The objective of this systematic review is to assess factors associated with HPV vaccination among AI/ANs in the USA.

METHODS AND ANALYSIS

A systematic review is proposed to synthesise the current literature on HPV vaccination factors in AI/ANs from 1 July 2006 until 30 September 2019. As applicable, controlled vocabulary terms, keywords and special features (eg, limits, explode and focus) will be incorporated into database searches. To maximise the identification of relevant studies, citation indexes and databases that index dissertations, preprints and grey literature are included. Studies will be screened and selected independently in two stages. In stage 1, titles and abstracts will be screened. In stage 2, full-text articles will be screened and selected. A data extraction form and quality assessment tool will be piloted, revised and implemented. If available, measures of frequency and association will be presented. A narrative synthesis of the included studies will also be undertaken and reported.

ETHICS AND DISSEMINATION

As our review will use publicly available data and publications, an Institutional Review Board review will not be required. We will disseminate the findings from this review through peer-reviewed publication(s) and conference presentation(s).

POTENTIAL AMENDMENTS

In the event of amendments to the protocol, we will provide the date, rationale, and description of the change for each amendment.

PROSPERO REGISTRATION NUMBER

CRD42020156865.

Updating the AIHTS Trapping Standards to Improve Animal Welfare and Capture Efficiency and Selectivity

In 1999, after pressure from the European Union, an Agreement on International Humane Trapping Standards (AIHTS) that would result in the banning of the steel-jawed leghold traps in the European Community, Canada, and Russia was signed. The United States implemented these standards through an Agreed Minute with the European Community. Over the last two decades, scientists have criticized the AIHTS for (1) omitting species that are commonly trapped; (2) threshold levels of trap acceptance that are not representative of state-of-the-art trap technology; (3) excluding popular traps which are commonly used by trappers although they are known to cause prolonged pain and stress to captured animals; (4) inadequate coverage of capture efficiency and species selectivity (i.e., number of captures of target and non-target species) performance. Concerns about the ability of standards and test procedures to ensure animal welfare, and about the implementation of standards, have also been voiced by wildlife biologists, managers, and conservation groups. In this review, we present a synopsis of current trapping standards and test procedures, and we compare the standards to a then contemporary 1985-1993 Canadian trap research and development program. On the basis of the above-noted concerns about AIHTS, and our experience as wildlife professionals involved in the capture of mammals, we formulated the following hypotheses: (1) the list of mammal species included in the AIHTS is incomplete; (2) the AIHTS have relatively low animal welfare performance thresholds of killing trap acceptance and do not reflect state-of-the-art trapping technology; (3) the AIHTS animal welfare indicators and injuries for restraining traps are insufficient; (4) the AIHTS testing procedures are neither thorough nor transparent; (5) the AIHTS protocols for the use of certified traps are inadequate; (6) the AIHTS procedures for the handling and dispatching of animals are nonexistent; (7) the AIHTS criteria to assess trap capture efficiency and species selectivity are inappropriate. We conclude that the AIHTS do not reflect state-of-the-art trapping technology, and assessment protocols need to be updated to include trap components and sets, animal handling and dispatching, and trap visit intervals. The list of traps and species included in the standards should be updated. Finally, the concepts of capture efficiency and trap selectivity should be developed and included in the standards. Based on our review, it is clear that mammal trapping standards need to be revisited to implement state-of-the-art trapping technology and improve capture efficiency and species selectivity. We believe that a committee of international professionals consisting of wildlife biologists and veterinarians with extensive experience in the capture of mammals and animal welfare could produce new standards within 1-2 years. We propose a series of measures to fund trap testing and implement new standards.

Reporting animal research: Explanation and elaboration for the ARRIVE guidelines 2.0

Improving the reproducibility of biomedical research is a major challenge. Transparent and accurate reporting is vital to this process; it allows readers to assess the reliability of the findings and repeat or build upon the work of other researchers. The ARRIVE guidelines (Animal Research: Reporting In Vivo Experiments) were developed in 2010 to help authors and journals identify the minimum information necessary to report in publications describing in vivo experiments. Despite widespread endorsement by the scientific community, the impact of ARRIVE on the transparency of reporting in animal research publications has been limited. We have revised the ARRIVE guidelines to update them and facilitate their use in practice. The revised guidelines are published alongside this paper. This explanation and elaboration document was developed as part of the revision. It provides further information about each of the 21 items in ARRIVE 2.0, including the rationale and supporting evidence for their inclusion in the guidelines, elaboration of details to report, and examples of good reporting from the published literature. This document also covers advice and best practice in the design and conduct of animal studies to support researchers in improving standards from the start of the experimental design process through to publication.

Limited by our limitations

Study limitations represent weaknesses within a research design that may influence outcomes and conclusions of the research. Researchers have an obligation to the academic community to present complete and honest limitations of a presented study. Too often, authors use generic descriptions to describe study limitations. Including redundant or irrelevant limitations is an ineffective use of the already limited word count. A meaningful presentation of study limitations should describe the potential limitation, explain the implication of the limitation, provide possible alternative approaches, and describe steps taken to mitigate the limitation. This includes placing research findings within their proper context to ensure readers do not overemphasize or minimize findings. A more complete presentation will enrich the readers' understanding of the study's limitations and support future investigation.

Independent discussion sections for improving inferential reproducibility in published research

There is a reproducibility crisis in science. There are many potential contributors to replication failure in research across the translational continuum. In this perspective piece, we focus on the narrow topic of inferential reproducibility. Although replication of methods and results is necessary to demonstrate reproducibility, it is not sufficient. Also fundamental is consistent interpretation in the Discussion section. Current deficiencies in the Discussion sections of manuscripts might limit the inferential reproducibility of scientific research. Lack of contextualisation using systematic reviews, overinterpretation and misinterpretation of results, and insufficient acknowledgement of limitations are common problems in Discussion sections; these deficiencies can harm the translational process. Proposed solutions include eliminating or not reading Discussions, writing accompanying editorials, and post-publication review and comments; however, none of these solutions works very well. A second Discussion written by an independent author with appropriate expertise in research methodology is a new testable solution that could help probe inferential reproducibility, and address some deficiencies in primary Discussion sections.

Standard of reporting animal-based experimental research in Indian Journal of Pharmacology

Objective:

The objective of present study was to survey and determine the reporting standards of animal studies published during three years from 2012 to 2014 in the Indian Journal of Pharmacology (IJP).

Material and Methods:

All issues of IJP published in the year 2012, 2013 and 2014 were reviewed to identify animal studies. Each animal study was searched for 15 parameters specifically designed to review standards of animal experimentation and research methodology.

Observation:

All published studies had clearly defined aims and objectives while a statement on ethical clearance about the study protocol was provided in 97% of papers. Information about animal strain and sex was given in 91.8% and 90% of papers respectively. Age of experimental animals was mentioned by 44.4% papers while source of animals was given in 50.8% papers. Randomization was reported by 37.4% while 9.9% studies reported blinding. Only 3.5% studies mentioned any limitations of their work.

Conclusion:

Present study demonstrates relatively good reporting standards in animal studies published in IJP. The items which need to be improved are randomization, blinding, sample size calculation, stating the limitations of study, sources of support and conflict of interest. The knowledge shared in the present paper could be used for better reporting of animal based experiments.

Opioid-induced constipation in patients with chronic noncancer pain in the USA, Canada, Germany, and the UK: descriptive analysis of baseline patient-reported outcomes and retrospective chart review

BACKGROUND

The characteristics of patients who suffer from noncancer pain and opioid-induced constipation are not well understood.

METHODS

Cross-sectional patient survey and chart review data from the baseline assessment of an ongoing longitudinal study in the USA, Canada, Germany, and the UK were evaluated via descriptive statistics. Participants had confirmation of daily opioid therapy ≥30 mg for ≥4 weeks and self-reported opioid-induced constipation. Response to laxatives was defined by classifying participants into categories of laxative use and evaluating the prevalence of inadequate response to one laxative agent and two or more agents from at least two different laxative classes. Outcomes included the Patient Assessment of Constipation-Symptoms, Work Productivity and Activity Impairment Questionnaire-Specific Health Problem, EuroQOL 5 Dimensions, and Global Assessment of Treatment Benefit, Satisfaction, and Willingness to Continue.

RESULTS

Patients reported a mean of 1.4 bowel movements not preceded by laxatives and 3.7 bowel movements with laxative use per week; 83% wanted at least one bowel movement per day. Most commonly reported on Patient Assessment of Constipation-Symptoms were straining/squeezing to pass bowel movements (83%), bowel movements too hard (75%), flatulence (69%), and bloating (69%). Eighty-four percent were taking natural or behavioral therapies; 60% were taking at least one over-the-counter laxative; and 19% were taking at least one prescription laxative. Prevalence of inadequate response to one laxative agent was 94%; inadequate response to two or more agents from at least two different laxative classes was 27%. Mean Work Productivity and Activity Impairment Questionnaire-Specific Health Problem values for percent work time missed, percent impairment while working, and percent activity impairment were 9%, 32% (equivalent of 14 hours of lost productivity per week), and 38%. Mean EuroQOL 5 Dimensions index and visual analog scale scores were 0.49 and 50.6, respectively. Forty-four percent reported being satisfied with their treatment for constipation.

CONCLUSION

Patients treated with opioids for noncancer pain commonly endure constipation symptoms that limit their work productivity and overall health-related quality of life while adhering to treatments that provide little relief. Further research is needed to identify more efficacious constipation therapies for this patient population.

There was less self-critique among basic than in clinical science articles in three rheumatology journals

OBJECTIVES

There is concern that self-critique with authors acknowledging limitations of their work is not given due importance in scientific articles. We had the impression that this was more true for articles in basic compared with clinical science. We thus surveyed for the presence of self-critique in the discussion sections of the original articles in three rheumatology journals with attention to differences between the basic and the clinical science articles.

STUDY DESIGN AND SETTING

The discussion sections of the original articles in January, May, and September 2012 issues of Annals of the Rheumatic Diseases, Arthritis and Rheumatism, and Rheumatology (Oxford) were surveyed (n = 223) after classifying each article as mainly related to clinical or basic science. The discussion sections were electronically scanned by two observers for the presence of the root word "limit" or its derivatives who also read each discussion section for the presence of any limitations otherwise voiced.

RESULTS

A limitation discussion in any form was present in only 19 (20.2%) or 29 (30.1%) of 94 basic science vs. 95 (73.6%) or 107 (82.3%) of 129 clinical science articles (P < 0.0001 for either observer).

CONCLUSION

Self-critique, especially lacking in basic science articles, should be given due attention.

All that glitters isn't gold: a survey on acknowledgment of limitations in biomedical studies

BACKGROUND

Acknowledgment of all serious limitations to research evidence is important for patient care and scientific progress. Formal research on how biomedical authors acknowledge limitations is scarce.

OBJECTIVES

To assess the extent to which limitations are acknowledged in biomedical publications explicitly, and implicitly by investigating the use of phrases that express uncertainty, so-called hedges; to assess the association between industry support and the extent of hedging.

DESIGN

We analyzed reporting of limitations and use of hedges in 300 biomedical publications published in 30 high and medium -ranked journals in 2007. Hedges were assessed using linguistic software that assigned weights between 1 and 5 to each expression of uncertainty.

RESULTS

Twenty-seven percent of publications (81/300) did not mention any limitations, while 73% acknowledged a median of 3 (range 1-8) limitations. Five percent mentioned a limitation in the abstract. After controlling for confounders, publications on industry-supported studies used significantly fewer hedges than publications not so supported (p = 0.028).

LIMITATIONS

Detection and classification of limitations was--to some extent--subjective. The weighting scheme used by the hedging detection software has subjective elements.

CONCLUSIONS

Reporting of limitations in biomedical publications is probably very incomplete. Transparent reporting of limitations may protect clinicians and guideline committees against overly confident beliefs and decisions and support scientific progress through better design, conduct or analysis of new studies.