The CONSORT statement: revised recommendations for improving the quality of reports of parallel group randomized trials

To comprehend the results of a randomised controlled trial (RCT), readers must understand its design, conduct, analysis, and interpretation. That goal can be achieved only through total transparency from authors. Despite several decades of educational efforts, the reporting of RCTs needs improvement. Investigators and editors developed the original CONSORT (Consolidated Standards of Reporting Trials) statement to help authors improve reporting by use of a checklist and flow diagram. The revised CONSORT statement presented here incorporates new evidence and addresses some criticisms of the original statement. The checklist items pertain to the content of the Title, Abstract, Introduction, Methods, Results, and Discussion. The revised checklist includes 22 items selected because empirical evidence indicates that not reporting this information is associated with biased estimates of treatment effect, or because the information is essential to judge the reliability or relevance of the findings. We intended the flow diagram to depict the passage of participants through an RCT. The revised flow diagram depicts information from four stages of a trial (enrolment, intervention allocation, follow-up, and analysis). The diagram explicitly shows the number of participants, for each intervention group, included in the primary data analysis. Inclusion of these numbers allows the reader to judge whether the authors have done an intention-to-treat analysis. In sum, the CONSORT statement is intended to improve the reporting of an RCT, enabling readers to understand a trial's conduct and to assess the validity of its results

Missed medical appointments during shifts to and from daylight saving time

Transitions into and out of Daylight Saving Time (DST) can provide insights into how a minor change to a regular sleep–wake cycle can inadvertently affect health. We examined the relationship between DST and missed medical appointments. Using a large dataset, the proportion of missed appointments were examined prior and post spring and autumn clock changes. As predicted, the number of missed medical appointments significantly increased following the spring (forward) clock change and the week of the clock change. This trend was reversed following the transition out of DST. The implications of scheduling appointments around DST to increase attendance are discussed

Estimation of gestational age in early pregnancy from crown-rump length when gestational age range is truncated: the case study of the INTERGROWTH-21st Project.

BACKGROUND: Fetal ultrasound scanning is considered vital for routine antenatal care with first trimester scans recommended for accurate estimation of gestational age (GA). A reliable estimate of gestational age is key information underpinning clinical care and allows estimation of expected date of delivery. Fetal crown-rump length (CRL) is recommended over last menstrual period for estimating GA when measured in early pregnancy i.e. 9+0-13+6 weeks. METHODS: The INTERGROWTH-21st Project is the largest prospective study to collect data on CRL in geographically diverse populations and with a high level of quality control measures in place. We aim to develop a new gestational age estimation equation based on the crown-rump length (CRL) from women recruited between 9+0-13+6 weeks. The main statistical challenge is modelling data when the outcome variable (GA) is truncated at both ends, i.e. at 9 and 14 weeks.We explored three alternative statistical approaches to overcome the truncation of GA. To evaluate these strategies we generated a data set with no truncation of GA that was similar to the INTERGROWTH-21st Project CRL data, which we used to explore the performance of different methods of analysis of these data when we imposed truncation at 9 and 14 weeks of gestation. These 3 methods were first tested in a simulation based study using a previously published dating equation by Verburg et al. and evaluated how well each of them performed in relation to the model from which the data were generated. After evaluating the 3 approaches using simulated data based on the Verburg equations, the best approach will be applied to the INTERGROWTH-21st Project data to estimate GA from CRL. RESULTS: Results of these rather "ad hoc" statistical methods correspond very closely to the "real data" for Verburg, a data set that is similar to the INTERGROWTH-21st project CRL data set. CONCLUSIONS: We are confident that we can use these approaches to get reliable estimates based on INTERGROWTH-21st Project CRL data. These approaches may be a solution to other truncation problems involving similar data though their application to other settings would need to be evaluated

Cluster randomised trials in the medical literature: two bibliometric surveys

Background: Several reviews of published cluster randomised trials have reported that about half did not take clustering into account in the analysis, which was thus incorrect and potentially misleading. In this paper I ask whether cluster randomised trials are increasing in both number and quality of reporting. Methods: Computer search for papers on cluster randomised trials since 1980, hand search of trial reports published in selected volumes of the British Medical Journal over 20 years. Results: There has been a large increase in the numbers of methodological papers and of trial reports using the term 'cluster random' in recent years, with about equal numbers of each type of paper. The British Medical Journal contained more such reports than any other journal. In this journal there was a corresponding increase over time in the number of trials where subjects were randomised in clusters. In 2003 all reports showed awareness of the need to allow for clustering in the analysis. In 1993 and before clustering was ignored in most such trials. Conclusion: Cluster trials are becoming more frequent and reporting is of higher quality. Perhaps statistician pressure works

How to spot a statistical problem: advice for a non-statistical reviewer

Statistical analyses presented in general medical journals are becoming increasingly sophisticated. BMC Medicine relies on subject reviewers to indicate when a statistical review is required. We consider this policy and provide guidance on when to recommend a manuscript for statistical evaluation. Indicators for statistical review include insufficient detail in methods or results, some common statistical issues and interpretation not based on the presented evidence. Reviewers are required to ensure that the manuscript is methodologically sound and clearly written. Within that context, they are expected to provide constructive feedback and opinion on the statistical design, analysis, presentation and interpretation. If reviewers lack the appropriate background to positively confirm the appropriateness of any of the manuscript’s statistical aspects, they are encouraged to recommend it for expert statistical review

“Does Short-term variation in fetal heart rate predict fetal acidaemia?” A Systematic review and meta-analysis

Objective: To evaluate the association of short-term variation (STV) of the fetal heart rate in predicting fetal acidaemia at birth. Methods: The search strategy employed searching of electronic databases (MEDLINE, Web of Science, Scopus, and Google Scholar) and reference lists of relevant studies. Data was extracted from studies, adhering strictly to the following criteria: singleton pregnancy at ≥ 24 weeks gestation, computerised CTG (index test) and calculation of STV before delivery. The outcome measure was arterial pH assessed in cord blood obtained at birth. Results: Meta-analysis showed moderate accuracy of STV in predicting fetal acidaemia with a sensitivity of 0.57 (95% CI: 0.45 to 0.68), specificity of 0.81 (95% CI: 0.69 to 0.89), positive likelihood ratio of 3.14 (95% CI: 2.13 to 4.63) and negative likelihood ratio of 0.58, (95% CI: 0.46 to 0.72). However, in intra-uterine growth restricted fetuses, a small improvement in detecting acidaemia was observed; with a sensitivity of 0.63, (95% CI: 0.49 to 0.75) and negative likelihood ratio of 0.50, (95% CI: 0.31 to 0.80). Conclusion: STV appears to be a moderate predictor for fetal acidaemia. However, its usefulness as a stand-alone test in predicting acidaemia in clinical setting remains to be determined

The conceptualisation and measurement of DSM-5 Internet Gaming Disorder: the development of the IGD-20 Test

Background: Over the last decade, there has been growing concern about ‘gaming addiction’ and its widely documented detrimental impacts on a minority of individuals that play excessively. The latest (fifth) edition of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-5) included nine criteria for the potential diagnosis of Internet Gaming Disorder (IGD) and noted that it was a condition that warranted further empirical study. Aim: The main aim of this study was to develop a valid and reliable standardised psychometrically robust tool in addition to providing empirically supported cut-off points. Methods: A sample of 1003 gamers (85.2% males; mean age 26 years) from 57 different countries were recruited via online gaming forums. Validity was assessed by confirmatory factor analysis (CFA), criterion-related validity, and concurrent validity. Latent profile analysis was also carried to distinguish disordered gamers from non-disordered gamers. Sensitivity and specificity analyses were performed to determine an empirical cut-off for the test. Results: The CFA confirmed the viability of IGD-20 Test with a six-factor structure (salience, mood modification, tolerance, withdrawal, conflict and relapse) for the assessment of IGD according to the nine criteria from DSM-5. The IGD-20 Test proved to be valid and reliable. According to the latent profile analysis, 5.3% of the total participants were classed as disordered gamers. Additionally, an optimal empirical cut-off of 71 points (out of 100) seemed to be adequate according to the sensitivity and specificity analyses carried

Locomotor muscle fatigue is not critically regulated after prior upper body exercise

This study examined the effects of prior upper body exercise on subsequent high-intensity cycling exercise tolerance and associated changes in neuromuscular function and perceptual responses. Eight men performed three fixed work-rate (85% peak power) cycling tests: 1) to the limit of tolerance (CYC); 2) to the limit of tolerance after prior high-intensity arm-cranking exercise (ARM-CYC); and 3) without prior exercise and for an equal duration as ARM-CYC (ISOTIME). Peripheral fatigue was assessed via changes in potentiated quadriceps twitch force during supramaximal electrical femoral nerve stimulation. Voluntary activation was assessed using twitch interpolation during maximal voluntary contractions. Cycling time during ARM-CYC and ISOTIME (4.33 ± 1.10 min) was 38% shorter than during CYC (7.46 ± 2.79 min) (P < 0.001). Twitch force decreased more after CYC (−38 ± 13%) than ARM-CYC (−26 ± 10%) (P = 0.004) and ISOTIME (−24 ± 10%) (P = 0.003). Voluntary activation was 94 ± 5% at rest and decreased after CYC (89 ± 9%, P = 0.012) and ARM-CYC (91 ± 8%, P = 0.047). Rating of perceived exertion for limb discomfort increased more quickly during cycling in ARM-CYC [1.83 ± 0.46 arbitrary units (AU)/min] than CYC (1.10 ± 0.38 AU/min, P = 0.003) and ISOTIME (1.05 ± 0.43 AU/min, P = 0.002), and this was correlated with the reduced cycling time in ARM-CYC (r = −0.72, P = 0.045). In conclusion, cycling exercise tolerance after prior upper body exercise is potentially mediated by central fatigue and intolerable levels of sensory perception rather than a critical peripheral fatigue limit

A survey of statistics in three UK general practice journal

Background Many medical specialities have reviewed the statistical content of their journals. To our knowledge this has not been done in general practice. Given the main role of a general practitioner as a diagnostician we thought it would be of interest to see whether the statistical methods reported reflect the diagnostic process. Methods Hand search of three UK journals of general practice namely the British Medical Journal (general practice section), British Journal of General Practice and Family Practice over a one-year period (1 January to 31 December 2000). Results A wide variety of statistical techniques were used. The most common methods included t-tests and Chi-squared tests. There were few articles reporting likelihood ratios and other useful diagnostic methods. There was evidence that the journals with the more thorough statistical review process reported a more complex and wider variety of statistical techniques. Conclusions The BMJ had a wider range and greater diversity of statistical methods than the other two journals. However, in all three journals there was a dearth of papers reflecting the diagnostic process. Across all three journals there were relatively few papers describing randomised controlled trials thus recognising the difficulty of implementing this design in general practice

The effects of laryngeal mask airway passage simulation training on the acquisition of undergraduate clinical skills: a randomised controlled trial

Background\ud Effective use of the laryngeal mask airway (LMA) requires learning proper insertion technique in normal patients undergoing routine surgical procedures. However, there is a move towards simulation training for learning practical clinical skills, such as LMA placement. The evidence linking different amounts of mannequin simulation training to the undergraduate clinical skill of LMA placement in real patients is limited. The purpose of this study was to compare the effectiveness in vivo of two LMA placement simulation courses of different durations. \ud \ud Methods\ud Medical students (n = 126) enrolled in a randomised controlled trial. Seventy-eight of these students completed the trial. The control group (n = 38) received brief mannequin training while the intervention group (n = 40) received additional more intensive mannequin training as part of which they repeated LMA insertion until they were proficient. The anaesthetists supervising LMA placements in real patients rated the participants' performance on assessment forms. Participants completed a self-assessment questionnaire. \ud \ud Results\ud Additional mannequin training was not associated with improved performance (37% of intervention participants received an overall placement rating of > 3/5 on their first patient compared to 48% of the control group, $X^2$ = 0.81, p = 0.37). The agreement between the participants and their instructors in terms of LMA placement success rates was poor to fair. Participants reported that mannequins were poor at mimicking reality. \ud \ud Conclusions\ud The results suggest that the value of extended mannequin simulation training in the case of LMA placement is limited. Educators considering simulation for the training of practical skills should reflect on the extent to which the in vitro simulation mimics the skill required and the degree of difficulty of the procedure. \ud \u