Daily Supplementation With Egg, Cow Milk, and Multiple Micronutrients Increases Linear Growth of Young Children with Short Stature

BACKGROUND

Childhood stunting is the most prevalent public health nutrition problem in low- and middle-income countries.

OBJECTIVE

This study aimed to determine whether daily supplementation in 12-18-mo-old undernourished Bangladeshi children with egg, cow milk, and multiple micronutrients improves linear growth.

METHODS

In the Bangladesh Environmental Enteric Dysfunction (BEED) study, a community-based intervention study, 12-18-mo-old children with length-for-age z score (LAZ) <1 were supplemented daily with an egg and 150 mL of milk for 90 feeding days, and 1 sachet of multiple micronutrient powder was provided daily for 60 feeding days. The change in LAZ over this period was compared with that in children of the same age and same baseline LAZ who were enrolled in the recently completed Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health (MAL-ED) Dhaka birth cohort study conducted in the same community where no nutrition intervention was provided. Difference-in-difference (DID) analysis was done and the effect size was adjusted for other possible covariates using a generalized estimating equation in a regression model.

RESULTS

A total of 472 children with LAZ <1 completed the intervention and data were available for 174 children in the comparison group. Compared with the comparison group, adjusted DID analysis revealed a change in LAZ in the intervention group of +0.23 (95% CI: 0.18, 0.29; P < 0.05). In a subgroup analysis, the changes were +0.27 (95% CI: 0.18, 0.35; P < 0.05) in stunted (LAZ <2) children and +0.19 (95% CI: 0.12, 0.27; P < 0.05) in children at risk of stunting (LAZ -1 to -2). No allergic reactions or other adverse events related to milk and egg consumption were observed.

CONCLUSIONS

Daily directly observed milk, egg, and multiple micronutrient supplementation may improve linear growth of stunted children. A randomized controlled trial with longer duration of supplementation coupled with an additional intervention aimed at reducing pathogen burden is warranted to confirm these results. This trial was registered at clinicaltrials.gov as NCT02812615.

WITHDRAWN: Occlusal interventions for periodontitis in adults

BACKGROUND

Occlusal interventions may be used in adults with periodontitis. At present there is little consensus regarding the indications and effectiveness of occlusal interventions in periodontal patients.

OBJECTIVES

To identify and analyse the evidence for the effect of occlusal interventions on adults who have periodontitis in relation to tooth loss, probing depths, clinical attachment level, adverse effects and patient-centred outcomes.

SEARCH METHODS

The search was last conducted in April 2008. We searched the Cochrane Oral Health Group's Trials Register (to 30th April 2008); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 1); MEDLINE (1966 to 30th April 2008); and EMBASE (1980 to 30th April 2008). There were no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing occlusal interventions in patients with periodontitis with a follow up of at least 3 months.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two review authors. Any disagreements between the review authors were resolved by discussion. The main investigator of the included trial was contacted to obtain missing information. The Cochrane Collaboration statistical guidelines were to be followed for data synthesis.

MAIN RESULTS

Abstracts of 54 papers were identified by the search. One paper was eligible for inclusion. This paper studied the effect of occlusal adjustment against no occlusal adjustment in patients who were treated with non-surgical and surgical periodontal therapy. Methodological quality assessment of the included paper revealed that randomisation of the patients into the treatment groups was adequate. Allocation concealment, masking of patients and clinicians were not reported and no response to author contact was received.Mean change in attachment level and mean pocket depth were reported in the included trial. Mean difference in clinical attachment level between occlusal intervention and control in the non-surgical group amounted to 0.38 mm (95% confidence interval (CI) 0.04 to 0.72) favouring the occlusal intervention group and was statistically significant. In the surgical group the mean difference in clinical attachment level between occlusal intervention and control amounted to 0.40 mm (95% CI 0.05 to 0.75) favouring the occlusal intervention group and was also statistically significant. The difference in mean pocket depth reduction between the occlusal intervention and control in both the surgical and non-surgical groups was less than 0.1 mm and was not statistically significant. Tooth loss, patient-centred affects and adverse effects were not reported. Meta-analysis was not possible due to the inclusion of only one study.

AUTHORS' CONCLUSIONS

There is only one randomised trial that has addressed this question. The data from this study are inconclusive. We therefore conclude there is no evidence for or against the use of occlusal interventions in clinical practice. This question can only be addressed by adequately powered bias-protected randomised controlled trials.

Methods of Intracanal Reinforcement in Primary Anterior Teeth-Assessing the Outcomes through a Systematic Literature Review

AIM

To assess how the various methods of intracanal reinforcement (short root canal posts) performed in their clinical and radiographic outcomes for restoring grossly broken down primary anterior teeth after pulpectomy for 1 year or longer follow-up period.

MATERIALS AND METHODS

Literature search of electronic databases (Sept 2013) and various journals (1980-Sept 2013) using medical subject headings and free text terms was conducted. For inclusion in quality assessment, prespecified inclusion criteria were applied. Quality assessment was performed by using 'The Cochrane collaboration's tool for assessing risk of bias'.

RESULTS

Seven relevant papers were selected for full text evaluation. After applying the inclusion criteria, only two trials could be considered for quality assessment. Both of these were classified as having high risk of bias.

CONCLUSION

The evidence to support any method of intracanal reinforcement for restoring grossly broken down anterior teeth is presently lacking. Further trials with well-defined methodology are needed. How to cite this article: Mittal N, Bhatia HP, Haider K. Methods of Intracanal Reinforcement in Primary Anterior Teeth- Assessing the Outcomes through a Systematic Literature Review. Int J Clin Pediatr Dent 2015;8(1):48-54.

Healthcare outcomes assessed with observational study designs compared with those assessed in randomized trials

BACKGROUND

Researchers and organizations often use evidence from randomized controlled trials (RCTs) to determine the efficacy of a treatment or intervention under ideal conditions. Studies of observational designs are often used to measure the effectiveness of an intervention in 'real world' scenarios. Numerous study designs and modifications of existing designs, including both randomized and observational, are used for comparative effectiveness research in an attempt to give an unbiased estimate of whether one treatment is more effective or safer than another for a particular population.A systematic analysis of study design features, risk of bias, parameter interpretation, and effect size for all types of randomized and non-experimental observational studies is needed to identify specific differences in design types and potential biases. This review summarizes the results of methodological reviews that compare the outcomes of observational studies with randomized trials addressing the same question, as well as methodological reviews that compare the outcomes of different types of observational studies.

OBJECTIVES

To assess the impact of study design (including RCTs versus observational study designs) on the effect measures estimated.To explore methodological variables that might explain any differences identified.To identify gaps in the existing research comparing study designs.

SEARCH METHODS

We searched seven electronic databases, from January 1990 to December 2013.Along with MeSH terms and relevant keywords, we used the sensitivity-specificity balanced version of a validated strategy to identify reviews in PubMed, augmented with one term ("review" in article titles) so that it better targeted narrative reviews. No language restrictions were applied.

SELECTION CRITERIA

We examined systematic reviews that were designed as methodological reviews to compare quantitative effect size estimates measuring efficacy or effectiveness of interventions tested in trials with those tested in observational studies. Comparisons included RCTs versus observational studies (including retrospective cohorts, prospective cohorts, case-control designs, and cross-sectional designs). Reviews were not eligible if they compared randomized trials with other studies that had used some form of concurrent allocation.

DATA COLLECTION AND ANALYSIS

In general, outcome measures included relative risks or rate ratios (RR), odds ratios (OR), hazard ratios (HR). Using results from observational studies as the reference group, we examined the published estimates to see whether there was a relative larger or smaller effect in the ratio of odds ratios (ROR).Within each identified review, if an estimate comparing results from observational studies with RCTs was not provided, we pooled the estimates for observational studies and RCTs. Then, we estimated the ratio of ratios (risk ratio or odds ratio) for each identified review using observational studies as the reference category. Across all reviews, we synthesized these ratios to get a pooled ROR comparing results from RCTs with results from observational studies.

MAIN RESULTS

Our initial search yielded 4406 unique references. Fifteen reviews met our inclusion criteria; 14 of which were included in the quantitative analysis.The included reviews analyzed data from 1583 meta-analyses that covered 228 different medical conditions. The mean number of included studies per paper was 178 (range 19 to 530).Eleven (73%) reviews had low risk of bias for explicit criteria for study selection, nine (60%) were low risk of bias for investigators' agreement for study selection, five (33%) included a complete sample of studies, seven (47%) assessed the risk of bias of their included studies,Seven (47%) reviews controlled for methodological differences between studies,Eight (53%) reviews controlled for heterogeneity among studies, nine (60%) analyzed similar outcome measures, and four (27%) were judged to be at low risk of reporting bias.Our primary quantitative analysis, including 14 reviews, showed that the pooled ROR comparing effects from RCTs with effects from observational studies was 1.08 (95% confidence interval (CI) 0.96 to 1.22). Of 14 reviews included in this analysis, 11 (79%) found no significant difference between observational studies and RCTs. One review suggested observational studies had larger effects of interest, and two reviews suggested observational studies had smaller effects of interest.Similar to the effect across all included reviews, effects from reviews comparing RCTs with cohort studies had a pooled ROR of 1.04 (95% CI 0.89 to 1.21), with substantial heterogeneity (I(2) = 68%). Three reviews compared effects of RCTs and case-control designs (pooled ROR: 1.11 (95% CI 0.91 to 1.35)).No significant difference in point estimates across heterogeneity, pharmacological intervention, or propensity score adjustment subgroups were noted. No reviews had compared RCTs with observational studies that used two of the most common causal inference methods, instrumental variables and marginal structural models.

AUTHORS' CONCLUSIONS

Our results across all reviews (pooled ROR 1.08) are very similar to results reported by similarly conducted reviews. As such, we have reached similar conclusions; on average, there is little evidence for significant effect estimate differences between observational studies and RCTs, regardless of specific observational study design, heterogeneity, or inclusion of studies of pharmacological interventions. Factors other than study design per se need to be considered when exploring reasons for a lack of agreement between results of RCTs and observational studies. Our results underscore that it is important for review authors to consider not only study design, but the level of heterogeneity in meta-analyses of RCTs or observational studies. A better understanding of how these factors influence study effects might yield estimates reflective of true effectiveness.

Randomisation to protect against selection bias in healthcare trials

BACKGROUND

Randomised trials use the play of chance to assign participants to comparison groups. The unpredictability of the process, if not subverted, should prevent systematic differences between comparison groups (selection bias). Differences due to chance will still occur and these are minimised by randomising a sufficiently large number of people.

OBJECTIVES

To assess the effects of randomisation and concealment of allocation on the results of healthcare studies.

SEARCH STRATEGY

We searched the Cochrane Methodology Register, MEDLINE, SciSearch and reference lists up to September 2009. In addition, we screened articles citing included studies (ISI Science Citation Index) and papers related to included studies (PubMed).

SELECTION CRITERIA

Eligible study designs were cohorts of studies, systematic reviews or meta-analyses of healthcare interventions that compared random allocation versus non-random allocation or adequate versus inadequate/unclear concealment of allocation in randomised trials. Outcomes of interest were the magnitude and direction of estimates of effect and imbalances in prognostic factors.

DATA COLLECTION AND ANALYSIS

We retrieved and assessed studies that appeared to meet the inclusion criteria independently. At least two review authors independently appraised methodological quality and extracted information. We prepared tabular summaries of the results for each comparison and assessed the results across studies qualitatively to identify common trends or discrepancies.

MAIN RESULTS

A total of 18 studies (systematic reviews or meta-analyses) met our inclusion criteria. Ten compared random allocation versus non-random allocation and nine compared adequate versus inadequate or unclear concealment of allocation within controlled trials. All studies were at high risk of bias.For the comparison of randomised versus non-randomised studies, four comparisons yielded inconclusive results (differed between outcomes or different modes of analysis); three comparisons showed similar results for random and non-random allocation; two comparisons had larger estimates of effect in non-randomised studies than in randomised trials; and two comparisons had larger estimates of effect in randomised than in non-randomised studies.Five studies found larger estimates of effect in trials with inadequate concealment of allocation than in trials with adequate concealment. The four other studies did not find statistically significant differences.

AUTHORS' CONCLUSIONS

The results of randomised and non-randomised studies sometimes differed. In some instances non-randomised studies yielded larger estimates of effect and in other instances randomised trials yielded larger estimates of effect. The results of controlled trials with adequate and inadequate/unclear concealment of allocation sometimes differed. When differences occurred, most often trials with inadequate or unclear allocation concealment yielded larger estimates of effects relative to controlled trials with adequate allocation concealment. However, it is not generally possible to predict the magnitude, or even the direction, of possible selection biases and consequent distortions of treatment effects from studies with non-random allocation or controlled trials with inadequate or unclear allocation concealment.

Evidence at a glance: error matrix approach for overviewing available evidence

Background

Clinical evidence continues to expand and is increasingly difficult to overview. We aimed at conceptualizing a visual assessment tool, i.e., a matrix for overviewing studies and their data in order to assess the clinical evidence at a glance.

Methods

A four-step matrix was constructed using the three dimensions of systematic error, random error, and design error. Matrix step I ranks the identified studies according to the dimensions of systematic errors and random errors. Matrix step II orders the studies according to the design errors. Matrix step III assesses the three dimensions of errors in studies. Matrix step IV assesses the size and direction of the intervention effect.

Results

The application of this four-step matrix is illustrated with two examples: peri-operative beta-blockade initialized in relation to surgery versus placebo for major non-cardiac surgery, and antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation. When clinical evidence is deemed both internally and externally valid, the size of the intervention effect is to be assessed.

Conclusion

The error matrix provides an overview of the validity of the available evidence at a glance, and may assist in deciding which interventions to use in clinical practice.

DISPACT trial: a randomized controlled trial to compare two different surgical techniques of DIStal PAnCreaTectomy - study rationale and design

BACKGROUND

Surgery is of increasing importance in the treatment and outcome of diseases of the pancreas worldwide. The incidence of pancreatic cancer (7-11/ 100,000 per year) has risen over the last years and surgical resection remains the only option for definite cure. Twenty-five percent of all resections are left of the superior mesenteric vein (distal pancreatectomy) and the appropriate closure technique for the pancreatic remnant remains unclear. Pancreatic fistulas are the most common (0-40%) and relevant postoperative complication. The optimal surgical strategy for pancreatic resection needs to be identified from the large number of surgical procedures available today.

PURPOSE

To evaluate the effectiveness of the two most common surgical techniques for distal pancreatectomy: stapler versus hand-sewn closure of the pancreatic remnant.

METHODS

In order to account for the uncertainty and clinical heterogeneity in the management of the pancreatic remnant following distal pancreatectomy, a study protocol is developed on the basis of a retrospective survey of patients in a center of excellence for pancreatic surgery and a systematic review with meta-analysis.

RESULTS

The DISPACT trial is a multicentered, randomized, controlled and patient-and observer-blinded trial using a two-group parallel group-sequential superiority design to compare the two techniques mentioned above. It will include approximately 336 randomized patients at up to 20 centers of excellence in pancreatic surgery, who are undergoing elective distal pancreatectomy for resectable benign, malign, and neuroendocrine tumors, chronic pancreatitis and pseudocysts of the pancreatic body and tail. The combination of the rate of postoperative pancreatic fistula and mortality will be evaluated as the primary endpoint. In addition, a set of general and surgical parameters will be analyzed. Pre-specified treatment manuals and continuous intra-operative (photo-documentation of surgical procedures and blinded evaluation thereafter) and on-site monitoring will assure that the treatment of the study patients conforms to protocol and will minimize clinical heterogeneity. Due to uncertainties about the effect sizes of the primary endpoint, an a priori planned interim analysis of the primary endpoint will be conducted after 224 evaluable patients are selected in order to reassess the initially planned sample size.

LIMITATIONS

Since pre-existing evidence was limited our initial sample size calculation is based on uncertain assumptions and may need to be modified in a planned interim analysis. Moreover, since surgical experience remains a potential confounder in surgical trials, learning curve bias has to be taken into account when analyzing the results. Given the participating trial sites, standardization of peri-and postoperative treatment represents a major issue of trial conduct.

CONCLUSIONS

A group-sequential study design accounts for the uncertainty of pre-existing evidence. Also, standardization of surgical and postoperative care and blinded outcome assessment as well as adjustment for varying surgical expertise will contribute to a high validity and generalizability of the results.

Occlusal interventions for periodontitis in adults

BACKGROUND

Occlusal interventions may be used in adults with periodontitis. At present there is little consensus regarding the indications and effectiveness of occlusal interventions in periodontal patients.

OBJECTIVES

To identify and analyse the evidence for the effect of occlusal interventions on adults who have periodontitis in relation to tooth loss, probing depths, clinical attachment level, adverse effects and patient-centred outcomes.

SEARCH STRATEGY

The search was last conducted in April 2008. We searched the Cochrane Oral Health Group's Trials Register (to 30th April 2008); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 1); MEDLINE (1966 to 30th April 2008); and EMBASE (1980 to 30th April 2008). There were no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing occlusal interventions in patients with periodontitis with a follow up of at least 3 months.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two review authors. Any disagreements between the review authors were resolved by discussion. The main investigator of the included trial was contacted to obtain missing information. The Cochrane Collaboration statistical guidelines were to be followed for data synthesis.

MAIN RESULTS

Abstracts of 54 papers were identified by the search. One paper was eligible for inclusion. This paper studied the effect of occlusal adjustment against no occlusal adjustment in patients who were treated with non-surgical and surgical periodontal therapy. Methodological quality assessment of the included paper revealed that randomisation of the patients into the treatment groups was adequate. Allocation concealment, masking of patients and clinicians were not reported and no response to author contact was received. Mean change in attachment level and mean pocket depth were reported in the included trial. Mean difference in clinical attachment level between occlusal intervention and control in the non-surgical group amounted to 0.38 mm (95% confidence interval (CI) 0.04 to 0.72) favouring the occlusal intervention group and was statistically significant. In the surgical group the mean difference in clinical attachment level between occlusal intervention and control amounted to 0.40 mm (95% CI 0.05 to 0.75) favouring the occlusal intervention group and was also statistically significant. The difference in mean pocket depth reduction between the occlusal intervention and control in both the surgical and non-surgical groups was less than 0.1 mm and was not statistically significant. Tooth loss, patient-centred affects and adverse effects were not reported. Meta-analysis was not possible due to the inclusion of only one study.

AUTHORS' CONCLUSIONS

There is only one randomised trial that has addressed this question. The data from this study are inconclusive. We therefore conclude there is no evidence for or against the use of occlusal interventions in clinical practice. This question can only be addressed by adequately powered bias-protected randomised controlled trials.

Outcomes of patients who participate in randomized controlled trials compared to similar patients receiving similar interventions who do not participate

BACKGROUND

Some people believe that patients who take part in randomised controlled trials (RCTs) face risks that they would not face if they opted for non-trial treatment. Others think that trial participation is beneficial and the best way to ensure access to the most up-to-date physicians and treatments. This is an updated version of the original Cochrane review published in Issue 1, 2005.

OBJECTIVES

To assess the effects of patient participation in RCTs ('trial effects') independent both of the effects of the clinical treatments being compared ('treatment effects') and any differences between patients who participated in RCTs and those who did not. We aimed to compare similar patients receiving similar treatment inside and outside of RCTs.

SEARCH STRATEGY

In March 2007, we searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, The Cochrane Methodology Register, SciSearch and PsycINFO for potentially relevant studies. Our search yielded 7586 new references. In addition, we reviewed the reference lists of relevant articles.

SELECTION CRITERIA

Randomized studies and cohort studies with data on clinical outcomes of RCT participants and similar patients who received similar treatment outside of RCTs.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed studies for inclusion, assessed study quality and extracted data.

MAIN RESULTS

We identified 30 new non-randomized cohort studies (45 comparisons): no new RCTs were found. This update now includes five RCTs (yielding 6 comparisons) and 80 non-randomized cohort studies (130 comparisons), with 86,640 patients treated in RCTs and 57,205 patients treated outside RCTs. In the randomised studies, patients were invited to participate in an RCT or not; these comparisons provided limited information because of small sample sizes (a total of 412 patients) and the nature of the questions they addressed. When the results of RCTs and non-randomized cohorts that reported dichotomous outcomes were combined, there were 98 comparisons; there was also heterogeneity (P < 0.00001, I(2) = 42.2%) between studies. No statistical significant differences were found for 85 of the 98 comparisons. Eight comparisons reported statistically significant better outcomes for patients treated within RCTs, and five comparisons reported statistically significant worse outcomes for patients treated within RCTs. There was significant heterogeneity (P < 0.00001, I(2) = 58.2%) among the 38 continuous outcome comparisons. No statistically significant differences were found for 30 of the 38 comparisons. Three comparisons reported statistically significant better outcomes for patients treated within RCTs, and five comparisons reported statistically significant worse outcomes for patients treated within RCTs.

AUTHORS' CONCLUSIONS

This review indicates that participation in RCTs is associated with similar outcomes to receiving the same treatment outside RCTs. These results challenge the assertion that the results of RCTs are not applicable to usual practice.

Outcomes of patients who participate in randomised controlled trials compared to similar patients receiving similar interventions who do not participate

BACKGROUND

Some people believe that patients who take part in randomised controlled trials (RCTs) face risks that they would not face if they opted for non-trial treatment. Others think that trial participation is beneficial and the best way to ensure access to the most up to date physicians and treatments.

OBJECTIVES

To assess the effects of patient participation in RCTs ('trial effects') independent both of the effects of the clinical treatments being compared ('treatment effects') and any differences between patients who participated in RCTs and those who did not.

SEARCH STRATEGY

In May 2001, we searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, The Cochrane Methodology Register, SciSearch and PsycINFO for potentially relevant studies. Our search yielded over 10,000 references. In addition, we reviewed the reference lists of relevant articles and wrote to over 250 investigators to try to obtain further information.

SELECTION CRITERIA

Randomised studies and cohort studies with data on clinical outcomes of RCT participants and similar patients who received similar treatment outside of RCTs.

DATA COLLECTION AND ANALYSIS

At least two reviewers independently assessed studies for inclusion, assessed study quality and extracted data. Study authors were contacted for additional information.

MAIN RESULTS

We included five randomised studies (yielding 6 comparisons) and 50 non-randomised cohort studies (85 comparisons), with 31,140 patients treated in RCTs and 20,380 patients treated outside RCTs. In the randomised studies, patients were invited to participate in an RCT or not; these comparisons provided limited information because of small sample sizes (a total of 412 patients) and the nature of the questions they addressed. There was statistically significant heterogeneity (P < 0.002, I(2) = 36.2%) among the 73 dichotomous outcome comparisons; none of the potential explanatory factors we investigated helped to explain this heterogeneity. No statistically significant differences were found for 63 of the 73 comparisons. Eight comparisons reported statistically significant better outcomes for patients treated within RCTs, and two comparisons reported statistically significant worse outcomes for patients treated within RCTs. There were no statistically significant differences in heterogeneity (P = 0.53, I(2) = 0%) or in outcomes (SMD 0.01, 95% CI -0.10 to 0.12) of patients treated within and outside RCTs in the 18 comparisons which had used continuous outcomes.

AUTHORS' CONCLUSIONS

This review indicates that participation in RCTs is not associated with greater risks than receiving the same treatment outside RCTs. These results challenge the assertion that the results of RCTs are not applicable to usual practice.

Better outcomes in pulpotomies on primary molars with MTA

DATA SOURCES

Medline, Cochrane Library, Embase, Science Citation Index and the China National Knowledge Infrastructure were used to source articles. In addition, identified papers' reference lists and their authors' other published literature were also scanned.

STUDY SELECTION

Studies of interest were randomised controlled trials of primary molar teeth where there was exposure of vital pulp caused by caries or trauma, with at least 6 months follow-up. It was required that selected teeth had no internal root resorption, inter-radicular and periapical bone destruction, no periodontal involvement, swelling, or sinus tract; they should be restorable with stainless steel crowns; and that outcomes were evaluated by clinical symptoms and radiographic evidence where the comparison followed a standard definition of success or failure, as shown by the number of teeth.

DATA EXTRACTION AND SYNTHESIS

Data were extracted from each study independently and entered into a database. Differences were resolved by discussion. Studies were scored for validity criteria according to the Jadad scale. Meta-analysis was performed using the software RevMan (version 4.2.8; Copenhagen; The Nordic Cochrane Centre, The Cochrane Collaboration, 2003). Heterogeneity between studies was assessed using a standard chi-square test. If there was homogeneity among the studies, the fixed-effect model (Peto method) was applied to aggregate the data. If homogeneity was rejected then sensitivity analyses were performed using a random-effects model.

RESULTS

Six studies met the inclusion criteria (giving a total of 381 teeth). There was a significant difference between the success rates of formocresol (FC)- and mineral trioxide aggregate (MTA)-treated pulpotomised primary molars (P<0.05) Clinical assessments and radiographic findings of the MTA versus FC pulpotomy suggested that MTA was superior to FC in pulpotomy, resulting in a lower failure rate [relative risk, 0.32 (95% confidence interval, 0.11-0.90) and 0.31 (95% confidence interval, 0.13-0.74) respectively].

CONCLUSIONS

The results demonstrate that in primary molar teeth with vital pulp exposure caused by caries or trauma, a pulpotomy performed with MTA results in better clinically and radiographically observed outcomes. Fewer undesirable responses were recorded for MTA than when FC was used. Therefore, the study supports the use of MTA instead of FC as wound dressing when performing pulpotomies on primary molars.

Improving the use of research evidence in guideline development: 7. Deciding what evidence to include

BACKGROUND

The World Health Organization (WHO), like many other organisations around the world, has recognised the need to use more rigorous processes to ensure that health care recommendations are informed by the best available research evidence. This is the seventh of a series of 16 reviews that have been prepared as background for advice from the WHO Advisory Committee on Health Research to WHO on how to achieve this.

OBJECTIVES

We reviewed the literature on what constitutes "evidence" in guidelines and recommendations.

METHODS

We searched PubMed and three databases of methodological studies for existing systematic reviews and relevant methodological research. We did not conduct systematic reviews ourselves. Our conclusions are based on the available evidence, consideration of what WHO and other organisations are doing and logical arguments. KEY QUESTION AND ANSWERS: We found several systematic reviews that compared the findings of observational studies with randomised trials, a systematic review of methods for evaluating bias in non-randomised trials and several descriptive studies of methods used in systematic reviews of population interventions and harmful effects. What types of evidence should be used to address different types of questions? The most important type of evidence for informing global recommendations is evidence of the effects of the options (interventions or actions) that are considered in a recommendation. This evidence is essential, but not sufficient for making recommendations about what to do. Other types of required evidence are largely context specific. The study designs to be included in a review should be dictated by the interventions and outcomes being considered. A decision about how broad a range of study designs to consider should be made in relationship to the characteristics of the interventions being considered, what evidence is available, and the time and resources available. There is uncertainty regarding what study designs to include for some specific types of questions, particularly for questions regarding population interventions, harmful effects and interventions where there is only limited human evidence. Decisions about the range of study designs to include should be made explicitly. Great caution should be taken to avoid confusing a lack of evidence with evidence of no effect, and to acknowledge uncertainty. Expert opinion is not a type of study design and should not be used as evidence. The evidence (experience or observations) that is the basis of expert opinions should be identified and appraised in a systematic and transparent way.

Chloroquine or amodiaquine combined with sulfadoxine-pyrimethamine for treating uncomplicated malaria

BACKGROUND

Chloroquine (CQ), amodiaquine (AQ), and sulfadoxine-pyrimethamine (SP) are inexpensive drugs, but treatment failure is a problem. Combination therapy may reduce treatment failure. CQ or AQ plus SP are affordable options of combination treatment, but there is debate about their effectiveness.

OBJECTIVES

To assess the combination of CQ or AQ plus SP compared with SP alone for first-line treatment of uncomplicated falciparum malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (April 2005), CENTRAL (The Cochrane Library Issue 2, 2005), MEDLINE (1966 to April 2005), EMBASE (1974 to April 2005), LILACS (1982 to April 2005), Science Citation Index (1981 to April 2005), African Index Medicus (1993 to 1998), and reference lists. We also contacted researchers at relevant organizations and a pharmaceutical company.

SELECTION CRITERIA

Randomized controlled trials in adults or children with uncomplicated Plasmodium falciparum malaria were eligible for inclusion. The main outcomes of interest were total and clinical failure at day 28 follow up and serious adverse events.

DATA COLLECTION AND ANALYSIS

Two people independently applied the inclusion criteria. One author extracted data and another checked them independently. We used relative risk (RR) and 95% confidence intervals (CI).

MAIN RESULTS

Twelve trials (2107 participants) met the inclusion criteria. A meta-analysis of five AQ trials (461 participants) showed a statistically significant reduction in total failure at day 28 with the combination therapy (RR 0.64, 95% CI 0.46 to 0.91), and meta-analysis of three trials (384 participants) showed a significant reduction in clinical failure at day 28 (RR 0.23, 95% CI 0.11 to 0.49). The statistical significance in the total failure analysis was sensitive to losses to follow up. Data from two CQ trials showed no advantage for total failure with combination therapy at day 28. There was no evidence from the included trials of serious adverse events.

AUTHORS' CONCLUSIONS

The evidence base is not strong enough to support firm conclusions. The available evidence suggests that AQ plus SP can achieve less treatment failure than SP, but this might depend on existing levels of parasite resistance to the individual drugs.

Alpha-fetoprotein and/or liver ultrasonography for liver cancer screening in patients with chronic hepatitis B

BACKGROUND

Chronic hepatitis B infection may cause liver cancer (hepatocellular carcinoma (HCC)). Alpha-fetoprotein (AFP) and liver ultrasonography (US) are used to screen these patients for HCC. It is uncertain whether screening is worthwhile.

OBJECTIVES

To review randomized trials on screening for HCC with alpha-fetoprotein and/or liver ultrasonography among people with hepatitis B surface antigen (HBsAg) whether asymptomatic or with clinical liver disease.

SEARCH STRATEGY

Relevant reports were searched from electronic databases until August 2002 (The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Controlled Trials Register, MEDLINE, EMBASE, HealthStar, and the Chinese Medical Literature Electronic Databases, MedCyber) supplemented with manual searches on the bibliographies of papers found and communication to people familiar with chronic hepatitis B.

SELECTION CRITERIA

Randomized trials on screening for liver cancer were included irrespective of language. Studies were excluded if the hepatitis B status was uncertain, if patients were not adequately followed, if the screening tests were not sensitive, widely-used ones, or if the test was used for diagnosis rather than screening for HCC.

DATA COLLECTION AND ANALYSIS

We analyzed independently all the studies considered for inclusion. We wrote to the relevant authors for further information. Data were analyzed with Peto's odds ratio (OR) with 95% confidence interval (CI).

MAIN RESULTS

Two trials met the selection criteria. One trial (n = 18,816) compared bi-annual AFP plus US screening with no screening for five years. No data on all-cause mortality were available. The two groups did not differ significantly regarding HCC mortality (OR 0.81; 95% CI 0.54 to 1.22). Number of patients with HCC was significantly increased in the screeened group (OR 1.37; 95% CI 1.00 to 1.88). Most HCCs in the screened group, but none in the control group, were at an early stage. The survival rate of patients with resected HCC in the screened group reached 52.7% after three and five years, but was 0% for those in the control group. The authors' estimated lead-time for HCC was 5.4 months, suggesting that screening prolonged the survival of HCC. Another trial (n = 1069) compared AFP plus US versus AFP screening, but could not decide which approach was superior due to the small sample size (number of detected HCC: OR 0.74; 95% CI 0.26 to 2.12).

REVIEWER'S CONCLUSIONS

There are not enough quality trials to support or refute screening of HBsAg-positive patients for HCC. It is possible that screening may be effective, but also that harm caused by screening/treatment may outweigh any gain. More and better-designed large randomized trials are required.