Enablers and disablers allowing trainees' abstracts to proceed to full manuscripts: lessons from a large neonatal training program

OBJECTIVE

To study trainee and supervisor perspectives for success or failure of conversion of abstracts to full manuscripts.

STUDY DESIGN

Abstracts presented by trainees between 2000 and 2005 were identified from the syllabi of the Paediatric Academic Society, Canadian Paediatric Society and Hot Topics meetings. The trainee and senior supervisor for each abstract were asked to complete a web-based survey that explored enablers and disablers.

RESULT

Of the 187 abstracts identified, 62 (33%) had trainees as primary authors. Of these, the responses of 42 (68%) trainees and 50 (81%) supervisors were collected; the responses of 21 (50%) trainees and 19 (38%) supervisors reported success in converting the abstract to a manuscript. According to trainees, good research idea, supportive supervisors and practical design were the main enablers, whereas limited time for research and the limited data collection only for abstracts were the main disablers. According to supervisors, adequate research time and the trainees' interest were the main enablers, whereas limited data collection and lack of trainees' interest were the main disablers. Specified research training, allocation of protected research time and making publication mandatory were suggested by both to enhance publication rate.

CONCLUSION

Training programs should consider research training needs and provide dedicated time to improve research productivity by trainees.

Fruit and vegetable intake and bone health in women aged 45 years and over: a systematic review

High fruit and vegetable intake may be associated with improved bone status among women aged ≥ 45 years. This is the first systematic review that specifically assessed this association and identified research gaps. The benefits of fruit and vegetables (F&V) on bone health remain unclear. Further studies are needed.

INTRODUCTION

F&V have several components that are beneficial to bones. Some studies report that high F&V intake is associated with improved bone status in middle aged and aged women; however, findings are inconsistent. The objective was to systematically review observational and interventional studies that investigated the effects of F&V intake on incidence of osteoporotic fractures, bone mineral density (BMD), and bone turnover markers (BTM) in women aged ≥ 45 years and to identify potential research gaps.

METHODS

Electronic databases were searched, and peer-reviewed manuscripts published in English, with F&V intake as a main dietary exposure, were included. Data selection, extraction, and evaluation of risk of bias were performed independently by two reviewers.

RESULTS

Eight studies were included. One cohort study reported cross-sectional as well as longitudinal data. There was significant between-study heterogeneity in design, definition, and amount of F&V intake, outcomes, analyses, and reporting of results. Two studies had low, two had moderate, and four had high risk of bias. Among reports with low or moderate risk of bias, two cross-sectional analyses reported positive associations between F&V intake and BMD of the forearm, lumbar spine, or total hip, whereas one randomized controlled trial and two prospective cohort analyses reported no effects. One trial reported no associations between F&V and BTM.

CONCLUSIONS

Based on limited evidence, the benefits of F&V on bone health remain unclear for women aged ≥ 45 years. Further studies with low risk of bias are needed.

Dexamethasone versus prednisone for induction therapy in childhood acute lymphoblastic leukemia: a systematic review and meta-analysis

This systematic review and meta-analysis compared the efficacy and toxicity of dexamethasone (DEX) versus prednisone (PRED) for induction therapy in childhood acute lymphoblastic leukemia (ALL). We searched biomedical literature databases and conference proceedings for randomized controlled trials comparing DEX and PRED during induction therapy for childhood ALL. A total of eight studies were eligible for inclusion in this meta-analysis. DEX, in comparison with PRED, reduced events (that is, death from any cause, refractory or relapsed leukemia, or second malignancy; risk ratio (RR) 0.80; 95% confidence interval (CI), 0.68-0.94) and central nervous system relapse (RR 0.53; 95% CI, 0.44-0.65), but did not alter bone marrow relapse (RR 0.90; 95% CI, 0.69-1.18) or overall mortality (RR 0.91; 95% CI, 0.76-1.09). Patients receiving DEX had a higher risk of mortality during induction (RR 2.31; 95% CI, 1.46-3.66), neuro-psychiatric adverse events (RR 4.55; 95% CI, 2.45-8.46) and myopathy (RR 7.05; 95% CI, 3.00-16.58). There was no statistically significant difference in the risk of osteonecrosis, sepsis, fungal infection, diabetes or pancreatitis. DEX in induction therapy for children with ALL is more efficacious than PRED. However, DEX is also associated with more toxicity, and currently it remains unclear whether short-term superiority of DEX will also result in better overall survival.

Rupture of membranes before the age of viability and birth after the age of viability: comparison of outcomes in a matched cohort study

OBJECTIVE

To compare composite adverse outcome rate of infants <32 weeks gestational age (GA) who were born after preterm premature rupture of membranes (PPROM) at previable gestation to those born without PPROM.

STUDY DESIGN

Retrospective review of prospective collected data for infants discharged between 2004 and 2007 was conducted. Cases were infants with >7 days of PPROM that occurred before 24 weeks. Matched cohort consisted of infants born without PPROM (matched for GA, sex and admission date). Composite adverse outcome was assessed considering death or any of the following three severe morbidities (severe neurological injury, severe retinopathy of prematurity or chronic lung disease).

RESULT

The 29 cases had higher mean severity of illness score compared with 74 matched infants. Mean duration of ROM was 45 vs 2 days and mean GA at the ROM was 21 vs 27 weeks, respectively. Logistic regression confirmed significantly higher risk of composite adverse outcome rates for cases (69 vs 47%; P=0.02, adjusted odds ratio 4.0, 95% CI 1.2, 13.6).

CONCLUSION

The survival rate for infants born at <32 weeks following PPROM at previable age has improved significantly; however, these infants had a higher rate of adverse composite neonatal outcome.

Incorporation of femur length leads to underestimation of fetal weight in asymmetric preterm growth restriction

OBJECTIVE

To review the performance of a variety of biometry formulae for estimated fetal weight (EFW) in the management of severely growth restricted fetuses with abnormal umbilical artery Doppler at a single perinatal institution.

METHODS

Forty-three pregnancies were retrospectively reviewed. Inclusion criteria were: chromosomally/ structurally normal fetus; complete ultrasound biometry at < or = 7 days from delivery; EFW < 10(th) centile; absent/reversed end-diastolic flow in the umbilical arteries; and delivery at < 32 + 6 weeks. EFW accuracy and precision were compared among nine formulae utilizing combinations of head circumference (HC), biparietal diameter (BPD), abdominal circumference (AC) and femur length (FL) measurements.

RESULTS

Twenty-six (60.5%) fetuses showed asymmetric growth (HC/AC ratio > 95(th) centile). Analysis of the systematic and random errors associated with each formula showed that the birth weight of asymmetrically-grown fetuses was most closely approximated by the Hadlock equation that utilized BPD and AC measurements only. The birth weight of symmetrically-grown fetuses was most closely approximated by EFW derived from Hadlock equations that utilized > or = three biometry measurements, including FL. Incorporation of FL into Hadlock formulae led to significant underestimation of birth weight in the fetuses with asymmetric growth (mean percentage error +/- SD: EFW(FL-AC), -13.3 +/- 9.8%; EFW(BPD-FL-AC), -10.8 +/- 9.8%; EFW(HC-FL-AC), -11.8 +/- 9.3%; EFW(BPD-HC-FL-AC), -11.7 +/- 9.5%; P < 0.001). The same equations were accurate in fetuses with symmetric growth (EFW(FL-AC), 3.1 +/- 10.0%; EFW(BPD-FL-AC), 1.0 +/- 8.9%; EFW(HC-FL-AC), 0.3 +/- 8.7%; EFW(BPD-HC-FL-AC), 0.4 +/- 15.5%). Use of the best performing equation (Hadlock 3), which does not include FL, to estimate weight in asymmetrically-grown fetuses over 28 weeks' gestation, would have reduced the proportion of those with an underestimation of fetal weight of > 100 g from nine (50.0%) to three (16.7%).

CONCLUSIONS

Biometry methods that exclude FL should be considered in asymmetric intrauterine growth restriction associated with abnormal umbilical artery Doppler waveforms.

Quality of randomized clinical trials in juvenile idiopathic arthritis

OBJECTIVES

We evaluated the quality of randomized clinical trials (RCTs) of therapy for juvenile idiopathic arthritis (JIA) using an individual component approach and assessed temporal changes.

METHODS

A systematic review of the literature was performed to identify all RCTs involving exclusively JIA patients. Two investigators independently assessed the identified articles for six quality indicators: generation of allocation sequence, allocation concealment, masking, intention-to-treat (ITT) analysis, dropout rates and clearly stated primary outcome.

RESULTS

Fifty-two RCTs involving JIA patients were assessed. Generation of allocation sequence was unclear in 79% of the studies. Reporting of allocation concealment was adequate in only one-third of the studies. Masking was adequate in 73%, inadequate in 19% and unclear in 8% of the reports. ITT analysis was employed in 37% of the reports. Per-protocol analysis was used in 40% and in 23% the method was unclear. Most of the reports (67%) had dropout rates < or = 20%. About half of the reports (n = 25) failed to show a significant effect of the experimental treatment. No significant associations were found between the study results and quality indicators. With the exception of adequate masking and dropout rate, all quality indicators showed a trend of improvement over the decades.

CONCLUSIONS

The quality of RCTs in JIA based on the selected indicators was poor. Although there were some positive changes over time, the reporting and methodological quality of trials should be improved. New, more powerful and acceptable RCT designs should be developed in this patient population.

Continuous negative extrathoracic pressure or continuous positive airway pressure for acute hypoxemic respiratory failure in children

BACKGROUND

Acute hypoxemic respiratory failure (AHRF) is an important cause of mortality and morbidity in children. Positive pressure ventilation is currently the standard care, however, it does have complications. Continuous negative extrathoracic pressure ventilation (CNEP) or continuous positive airway pressure (CPAP) ventilation delivered via non-invasive approaches (Ni-CPAP) have shown certain beneficial effects in animal and uncontrolled human studies.

OBJECTIVES

The primary objective was to assess the effectiveness of CNEP or Ni-CPAP in pediatric patients with AHRF from non-cardiogenic causes.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2007, Issue 3); MEDLINE (January 1966 to July 2007); EMBASE (1980 to July 2007); CINAHL (1982 to July 2007); and published abstracts from the meetings of the American Thoracic Society and Pediatric Critical Care Meetings (1992 to 2007).

SELECTION CRITERIA

Randomized or quasi-randomized clinical trials of either CNEP or Ni-CPAP versus standard therapy (including positive pressure ventilation) involving children (at least 1 month old and less than 18 years of age at the time of randomization) who met the criteria for diagnosis of AHRF with at least one of the outcomes reported were included.

DATA COLLECTION AND ANALYSIS

Risks of bias of the included study was assessed using: concealment of allocation, blinding of intervention, completeness of follow up and blinding of outcome measurements. Data on relevant outcomes were abstracted and the effect size was estimated by calculating relative risk (RR) with 95% confidence intervals (CI) and risk difference (RD).

MAIN RESULTS

One eligible study published in an abstract format was identified. It studied 33 infants (18 controls, 15 receiving CNEP) with a clinical diagnosis of bronchiolitis and fraction of inspired oxygen (FiO(2)) > 40% were studied. This allowed a reduction in the FiO(2) (< 30% within one hour of initiation of therapy) in four patients in the CNEP group compared to none in the control group (RR 10.7, 95% CI 0.6 to 183.9). One infant required CPAP and one infant required nasal CPAP in the control group while all infants in the CNEP group were managed without intubation (RR for both outcomes 0.40, 95% CI 0.02 to 9.06).

AUTHORS' CONCLUSIONS

There is a lack of well designed, controlled experiments of non-invasive modes of respiratory support in children with AHRF. Reduction of in-hospital mortality is an important outcome and even a small reduction would be beneficial. Studies assessing other outcomes such as avoidance of intubation and its associated complications, reduction in hospital stay and improvement in patient comfort are also valuable in gauging the overall impact of these strategies.

Heparin-bonded catheters for prolonging the patency of central venous catheters in children

BACKGROUND

Central venous catheters (CVCs) are a mainstay in the management of critically ill children. However, these catheters are associated with mechanical and infectious complications which reduce their life span. Heparin bonding of catheters has shown promise in animal studies and in adults.

OBJECTIVES

The primary objective was to determine the effect of heparin-bonded CVCs on the duration of catheter patency in children. Secondary objectives were to determine the effect of heparin-bonded catheters on catheter related thrombosis, occlusion, sepsis and side effects.

SEARCH STRATEGY

We searched the Cochrane Peripheral Vascular Diseases (PVD) Group Trials Register (inception to August 2007) which contains trials identified through searches of MEDLINE (1966 to August 2007), EMBASE (1980 to August 2007), CINAHL (1982 to August 2007), and hand searches along with the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library 2007, Issue 3.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials of heparin-bonded catheters versus non-heparin bonded catheters or antibiotic-impregnated catheters that reported on any of the prespecified outcomes, without language restriction.

DATA COLLECTION AND ANALYSIS

Methodological quality of the trials was assessed using the information provided in the studies and by contacting authors. Data were extracted and the effect size was estimated and reported as relative risk (RR), risk difference (RD) or number needed to treat (NNT), as appropriate.

MAIN RESULTS

Two eligible studies reflecting 287 patients were included; both had good methodological quality. There was no difference in the duration of catheter patency between heparin bonded and non-heparin bonded catheters (median duration 7 days vs 6 days) reported in one study. There was no difference in the risk of catheter related thrombosis (RR 0.71, 95% CI 0.44 to 1.15; RD -0.05, 95% CI 0.13 to 0.02; I(2) = 79%). Data from one study revealed a statistically significant reduction in the risk of catheter occlusion (RR 0.06, 95% CI 0.00 to 1.07; RD -0.08, 95% CI -0.13 to -0.02; NNT 13, 95% CI 8 to 50), catheter-related infections (RR 0.06, 95% CI 0.01 to 0.41; RD -0.17, 95% CI -0.25 to -0.10; NNT 6, 95% CI 4 to 10) and catheter colonization (RR 0.21, 95% CI 0.06 to 0.71; RD -0.11, 95% CI -0.19 to -0.04; NNT 9, 95% CI 5 to 25) in the heparin-bonded catheter group.

AUTHORS' CONCLUSIONS

Two eligible studies on the use of heparin-bonded catheters versus placebo in children were identified. The use of heparin-bonded catheters is a promising therapy but warrants further studies.

Sildenafil for pulmonary hypertension in neonates

BACKGROUND

Persistent pulmonary hypertension in neonates (PPHN) is associated with high mortality. Currently, the therapeutic mainstay for PPHN is assisted ventilation and administration of inhaled nitric oxide (iNO). However, nitric oxide is costly and may not be appropriate in resource-poor settings. Approximately 30% of patients fail to respond to iNO. High concentrations of phosphodiesterases in the pulmonary vasculature has led to the use of phosphodiesterase inhibitors such as sildenafil or milrinone.

OBJECTIVES

To assess the efficacy and safety of Sildenafil in the treatment of persistent pulmonary hypertension in neonates.

SEARCH STRATEGY

MEDLINE, EMBASE, CINAHL databases were searched from their inception until March 2007; the Cochrane Central Register of Controlled Trials, the Cochrane Library, the reference lists of identified trials, and abstracts of meetings were searched without any language restriction.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials of Sildenafil compared with placebo or other pulmonary vasodilators, irrespective of dose, route and duration of administration in neonates with PPHN, were included if the trial reported any of the pre-specified outcomes.

DATA COLLECTION AND ANALYSIS

The methodological quality of the trials was assessed regarding how bias at study entry, study intervention and outcomes measurement was minimized. Data on relevant outcomes were extracted and the effect size was estimated and reported as relative risk (RR), risk difference (RD) and weighted mean difference (MD) as appropriate. The I-squared (I(2)) test of heterogeneity was applied.

MAIN RESULTS

Two small eligible trials (one full article and one abstract) were identified. The methodological quality of the trial presented in the full article was good. Information provided in the abstract was limited. The total number of enrolled patients in the two studies was 37. Both studies were performed in resource-limited settings where iNO and high frequency ventilation are not available. Both studies reported statistically significant improvement in oxygenation (reduction in oxygenation index) in the Sildenafil group. One study reported what would be, if replicated, a strongly protective effect on mortality (RR 0.17, 95% CI 0.03, 1.09) favoring the Sildenafil group. However, this result needs to be replicated in larger studies. No clinically important side effects were reported.

AUTHORS' CONCLUSIONS

The safety and effectiveness of sildenafil in the treatment of PPHN has not yet been established and its use should be restricted within the context of randomized controlled trials. Further randomized controlled trials of adequate power comparing Sildenafil with other pulmonary vasodilators are needed in moderately ill infants with PPHN.