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PubMed2004

A national evaluation of school breakfast clubs: evidence from a cluster randomized controlled trial and an observational analysis.

STUDY OBJECTIVE: To measure the health, educational and social impacts of breakfast club provision in schools serving deprived areas across England. DESIGN: A cluster randomized controlled trial and an observational analysis. SETTING: England, the UK. INTERVENTION: funding to establish a school-based breakfast club vs. control (no funding). MAIN RESULTS: Intention to treat analysis showed improved concentration (Trail Making Test Part A) amongst the intervention group at 3 months. Fewer pupils within the intervention group reported having skipped classes within the last month and fewer pupils within the intervention group reported having skipped 1 or more days of school within the last month at 1 year. Observational analysis at 1 year showed a higher proportion of primary-aged breakfast club attendees reported eating fruit for breakfast in comparison to non-attendees. A higher proportion of breakfast club attendees had borderline or abnormal conduct and total difficulties scores (primary-aged pupils) and prosocial score (secondary-aged pupils). CONCLUSIONS: Analyses revealed a mixed picture of benefit and apparent disbenefit. This study illustrated the challenges of evaluating a complex intervention in which the evaluators had less control than is usual in randomized trials over recruitment, eligibility checking and implementation. If the impact of new policy initiatives is to be assessed using the most robust forms of evaluation, social policy needs to be organized so that evaluations can be constructed as experiments. This is likely to prove most difficult where the perceived value of implementing an intervention rapidly is high.

Absenteeism↗
PubMed2003

Methodologic issues in randomized controlled trials of surgical interventions.

A physician's ability to make conclusions about the relative efficacy of interventions based on their clinical experience is limited frequently. Therefore, surgeons commonly use research evidence to guide their clinical practice. The randomized controlled trial is the strongest study design. However, randomization in itself does not guarantee the trial results are valid (free from bias). Understanding the potential impact of various methodologic features of a randomized controlled trial allows a clinician to determine the validity of a trial. We present a guide for evaluating the validity of randomized controlled trials giving special consideration to issues confronted in surgical trials.

Humans↗
PubMedDate not supplied

Flexible sigmoidoscopy as a colorectal cancer screening test in the general population: recruitment phase results of a randomized controlled trial in Lombardia, Italy.

UNLABELLED: A two arm multicentre randomized controlled trial is in progress to evaluate the efficacy of flexible sigmoidoscopy (FS) as a screening test for colorectal cancer in the general population. AIMS: To determine the acceptance rate and feasibility of FS as a colorectal cancer screening test in average-risk asymptomatic volunteers. Average-risk, asymptomatic subjects, aged 55-64 years and assisted by 244 general practitioners (GPs) in Lombardy, Italy, were invited by postal questionnaire (PQ) to enter a study for the prevention of colorectal cancer and asked to indicate their interest in, and willingness to undergo, screening: those responding positively were randomized to the intervention or control arms. GPs were trained in colorectal cancer screening and proposed free FS to their patients randomized to the intervention arm. All sigmoidoscopies were performed by experienced endoscopists. Small polyps were removed at FS. Colonoscopy was indicated for high risk polyps (size more than 5 mm, more than two adenomas, villous histology, severe dysplasia or malignancy). 40,945 subjects were invited. 667 PQs were returned undelivered due to postal failure. 7,892 (19.59%) subjects responded, 2,116 of whom (26.81%) were not included, presenting 1 or more exclusion criteria. We randomized 5,778 volunteers and performed 1,582 sigmoidoscopies out of 2,885 subjects in the intervention arm (54.84% acceptance rate). Although the screening procedure had a good attendance rate in the intervention group, involvement of the people invited was lower than expected. Future FS screening programmes will require a keener focus on recruitment strategies, mainly with participation of GPs.

Colorectal Neoplasms↗
PubMed1999

The implications of variation in outcome between health professionals for the design and analysis of randomized controlled trials.

Methodological work on randomized trials has largely concerned pharmacological interventions in which the effects of the attending health professional may be regarded as minor. In other clinical settings, such as surgery, talk or physical therapies, staff specific variation may make generalization problematic, undermining the value of the trial. Such variation has been the basis of some objections to controlled trial methodology and non-acceptance of trial results. The implication of this source of variation will be considered for studies in which different types of health professional deliver the intervention in each arm of the trial. Such a trial may involve individual patient or group randomization. Whichever method is used, it is argued that variation in outcome between health professionals may lead to design effects. These issues will be illustrated using data from a large trial comparing primary care service delivered by two types of medical doctor. Random effect models are most suitable for analyzing this type of trial, as they allow adjustment for patient characteristics whilst controlling for design effects. This type of model illustrates that there can be substantial variation in the performance within each category of doctor.

Bias↗
PubMed1979

A randomized controlled trial of geriatric screening and surveillance in general practice.

A randomized controlled trial of geriatric screening and surveillance was undertaken on a practice population of 295 patients aged 70 years or more over a two-year period. In the screened group (145 patients) many social problems were found and a total of 380 medical conditions were reported during the study period, 144 (38 per cent) of which were previously undetected. Conditions found most frequently involved the circulatory, musculoskeletal and nervous systems; 67 per cent of the conditions found were manageable, half being improved and the remainder resolved completely.The screening programme was found to increase the use of social and health services but it did also decrease the expected duration of stay in hospital.Independent assessment of patients in the study and control groups at the end of the two-year period showed that the screening programme had made no significant impact on the prevalence of socio-economic, functional, and medical disorders affecting health.We formed the firm impression that the study patients were made more comfortable (by control of pain) and less disabled, although there was no unequivocal objective evidence of this. They were, however, kept independent for longer.The findings are discussed and a model of geriatric care is suggested combining conventional management on demand with comprehensive screening to identify the high-risk patients on whom care might need to be focussed.

Aged↗
PubMed2004

The impact of day care on socially disadvantaged families: an example of the use of process evaluation within a randomized controlled trial.

AIM: This paper describes a process evaluation that was conducted alongside a randomized controlled trial of out-of-home pre-school day care. The evaluation aimed to: (1) describe the intervention; (2) document the day care received by participating families; (3) describe the social context of the trial; and (4) provide data to assist in the interpretation of trial outcomes. METHODS: The setting for the trial was an out-of-home day care Centre in Hackney, East London. Process data were collected through the use of questionnaires, interviews, and researcher field-notes. Data from questionnaires were collected from 120 mothers and included data on 143 children. Interviews were undertaken with 21 participating mothers. Staff also completed questionnaires and the Head of the Centre was interviewed. The quality of care provided was assessed using the Early Childhood Environment Rating Scale. RESULTS: Process data collected during the trial suggest that the day care provided was education-led, flexible in catering to families' needs, and was of a very high quality. The social context of the trial resulted in financial pressures, which may well have influenced the intervention provided. Data collected through in-depth interviews suggested that it may be the flexibility of day care that is particularly important in allowing women to return to paid employment, but that the loss of benefits when starting work may have meant no increase in household income. CONCLUSION: The paper illustrates the value of conducting a process evaluation alongside a randomized trial, particularly where complex interventions are involved. In this case, where the intervention was not provided by the research team, the evaluation allowed an insight into the content of a multifaceted intervention, which is useful in interpreting the trial's results, and in explaining the possible effects of the social context on the intervention.

Adult↗
PubMed2003

Assisted hatching--a meta-analysis of randomized controlled trials.

PURPOSE: To conduct a meta-analysis of randomized controlled trials (RCTs) on assisted hatching. METHODS: One hundred sixty-five studies were retrieved from the literature, but only 13 of them fitted our selection criteria. The meta-analysis was conducted using the RevMan software with the Peto-modified Mantel-Haenszel method. RESULTS: Assisted hatching increases the pregnancy [OR (+/-95% CI) = 2.51 (1.91-3.29)], implantation [OR (+/-95% CI) = 2.38 (1.87-3.03)], and ongoing pregnancy rates [OR (+/-95% CI) = 2.65 (1.85-3.79)] significantly in poor prognosis patients undergoing IVF or ICSI. For patients with repeated IVF failures, the OR (+/-95% CI) were 2.84 (1.99-4.06) for pregnancy, 2.53 (1.85-3.47) for implantation, and 3.51 (2.12-5.82) for ongoing pregnancy rates, in favor of assisted hatching. CONCLUSIONS: Assisted hatching increases the pregnancy, implantation, and ongoing pregnancy rates significantly in patients with a poor prognosis undergoing IVF or ICSI, particularly those with repeated failures.

Female↗
PubMed1995

Effects of "group detailing" on the prescribing of lipid-lowering drugs: a randomized controlled trial in Swedish primary care.

The objective was to study the effect of "academic group detailing" on the prescribing of lipid-lowering drugs in Swedish primary care. A randomized controlled trial was conducted, randomization being by group. Groups of doctors at 134 community health centres were randomly allocated to an intervention and a control group. The 67 intervention health centres were offered four sessions, conducted by a pharmacist, with group information on guidelines for the management of hyperlipidaemia. The number of prescriptions of lipid-lowering drugs per month increased in the intervention health centres and the increase was statistically different from the corresponding change in the control health centres among women in the age group 30-65 years (p = 0.03). The prescription of first-line lipid-lowering drugs increased by 20% in the intervention health centres (p = 0.03). "Academic group detailing" by pharmacists to primary care doctors can be an effective method for influencing prescribing practices.

Adult↗
PubMed1986

The use of a birthroom: a randomized controlled trial comparing delivery with that in the labour ward.

A randomized controlled trial of two environments for delivery was conducted at Queen Charlotte's Maternity Hospital. A total of 253 parous women expecting to have a labour ward delivery were invited to participate in the trial but only 148 agreed. These women were randomly allocated to be delivered either with standard labour ward management (n = 72) or in the birthroom--a small bedroom decorated in a homely manner, without facilities for epidural analgesia or electronic fetal monitoring (n = 76). Eleven women in the birthroom group and 10 in the labour ward group withdrew from the trial before labour and four were transferred from the birthroom to the labour ward when in labour. A questionnaire sent in the postnatal period to the women who completed the trial was returned by 80%. In the birthroom group there was significantly (i) decreased admission-to-delivery interval (ii) less analgesia (iii) more freedom of movement (iv) less suturing (v) increased rooming-in. No difference was found in the assessment of difficulty of labour nor in the method of subsequent infant feeding.

Clinical Trials as Topic↗
PubMed2000

Randomized controlled trial of exercise training for older people (Sendai Silver Center Trial; SSCT): study design and primary outcome.

Physical exercise is expected to improve and maintain physical function in older people, thus promoting health and preventing or postponing the onset of disability in later life. The Sendai Silver Center Trial (SSCT) was a randomized controlled trial designed to evaluate the efficacy of exercise training among healthy free-living older people. Sixty-five eligible participants, aged from 60 to 81 years, were randomly allocated to an exercise group or a control group. The subjects in the exercise group were asked to attend training classes at the Sendai Silver Center, a municipal health and welfare facility in the center of Sendai City, at least twice a week for 25 weeks. Each training class, lasting two hours, started with a warm-up session, followed by an endurance session with a bicycle ergometer, and a resistance exercise training session using rubber films, and ended with a cool-down session. The subjects in the control group were asked to attend recreational classes at the Center twice a month. There were no drop-outs or accidents during the intervention. Comparison of maximum oxygen consumption (VO2max) before and after the 25-week intervention revealed a significant increase in the exercise group (2.1 ml/kg/min) but no significant change in the control group. Our result is equivalent to the participants becoming younger in aerobic capacity by five years after six months of exercise training.

Aged↗
PubMed2000

Trends in dental and medical research and relevance of randomized controlled trials to common activities in general dentistry.

The aim was to study publication trends in dental and medical research as well as the proportion of randomized controlled trials in dental research (RCT-Ds) of relevance to common activities in general dentistry. The study was based on Medline searches, 1969 99 (MeSH terms). Data from Public Dental Services (county of Ostergötland, Sweden) were used to find the most common activities in the practice of general dentistry,. In dental research the annual number of publications had decreased from 5,900 in 1969 to 4,400 in 1999, corresponding to 9,100 and 14,000, respectively, in medical research. Clinical trials in dental research had increased to 7% and RCT-Ds to 5% of all dental research during 1969 99. In medicine, clinical trials and randomized controlled trials had increased to 2% and 1%, respectively. In dental and medical research, meta-analyses (MAs) totalled 0.1-0.2% in 1994 and 1999. One out of 200 dental research publications in 1979 99 was an RCT-D of relevance to the most common activities in general dentistry. These activities contributed to more than 80% of the dental care of children and adolescents and to more than 60% of the dental care of adults in 1999.

Adolescent↗
PubMed2002

Reporting randomized, controlled trials: where quality of reporting may be improved.

INTRODUCTION: Evidence-based medicine relies on reproducible, high-quality reporting in the literature. Previous evaluations, which have assessed 11 basic elements of design and analysis in top impact clinical journals (both nonsurgical and surgical), have demonstrated that the reporting quality is less than perfect, although improving. The current study evaluates the quality of reporting in Diseases of the Colon and Rectum and other clinically related journals to identify specific areas where future improvements may be made. METHODS: Two independent evaluators assessed all randomized, controlled trials published in Diseases of the Colon and Rectum in the years 1990, 1995, and 2000. Additional assessments for 2000 were performed on all randomized, controlled trials published in Annals of Surgery, Archives of Surgery, and Gastroenterology. The frequency of reporting of 11 explicitly defined, traditionally important, basic elements of design and analysis were determined. These elements included reporting of eligibility criteria, admission before allocation, randomization (and method), blinded assessment (patient and observer), complications, loss to follow-up, statistical approach and tests, and power calculation. RESULTS: Interobserver reliability was strong (kappa, 0.76). The number of randomized, controlled trials published in Diseases of the Colon and Rectum increased from 5 (in 1990) to 13 (in 1995) to 17 (in 2000). Of the 1990 randomized, controlled trials, an average of 60 percent of the 11 basic elements were reported. Of the 1995 randomized, controlled trials, 72 percent of the items were reported (P = 0.05), whereas of the 2000 randomized, controlled trials, 77 percent of the 11 items were reported (P < 0.002 vs. 1990). The best-reported items were eligibility criteria, discussion of statistical tests, and accounting for all patients lost to follow-up. Only 11 percent of the 2000 randomized, controlled trials reported statistical power calculations. For the other journals that were evaluated, 72 to 88 percent of items were reported, with eligibility criterion being the best consistently reported item and power calculation being the worst. CONCLUSIONS: For Diseases of the Colon and Rectum, the number of randomized, controlled trials and the quality of reporting is improving. However, although certain research standards are reported adequately, others are not. The calculation of statistical power is clearly important when interpreting randomized, controlled trial results (whether differences are reported or not), yet only 11 percent of studies contained this information. Improving the reporting of this single item would likely lead to improving the overall quality of clinical studies in colorectal surgery. Improved reporting might be best facilitated by having authors adhere to a list of explicitly determined elements that should be included.

Colonic Diseases↗
PubMed2000

Laser therapy: a randomized, controlled trial of the effects of low intensity Nd:YAG laser irradiation on lateral epicondylitis.

OBJECTIVE: To assess the effectiveness of low intensity laser therapy in the treatment of lateral epicondylitis. DESIGN: A double-masked, placebo-controlled, randomized clinical trial. SETTING: A physical medicine and rehabilitation clinic. PARTICIPANTS: Fifty-two ambulatory men and women (age range, 18-70 yr) with symptomatic lateral epicondylitis of more than 30 days in duration and a normal neurologic examination. INTERVENTION: Subjects were bloc randomized into 2 groups with a computer-generated schedule. All underwent irradiation for 60 seconds at 7 points along the symptomatic forearm 3 times weekly for 4 weeks by a masked therapist. The sole difference between the groups was that the probe of a 1.06-microm continuous wave laser emitted 204 mW/cm2 (12.24 J/cm2) for the treated subjects and was inactive for the control subjects. Subjects were assessed at the beginning, midpoint (session 6), and end (session 12) of treatment, as well as at follow-up 28 to 35 days after their last treatment. MAIN OUTCOME MEASURES: Pain in last 24 hours, tenderness to palpation, and patient's perception of change (benefit). RESULTS: The treated and untreated groups were well matched demographically. Masking was maintained for subjects and therapists; however, the groups did not vary to a statistically significant extent in terms of the main outcome measures either during treatment or at follow-up. Secondary outcome variables, such as grasp and pinch strength, medication use, and pain with grasp and pinch, also failed to statistically differ significantly between the groups. No significant treatment side effects were noted. CONCLUSION: Treatment with low intensity 1.06-microm laser irradiation within the parameters of this study was a safe but ineffective treatment of lateral epicondylitis. Further research seems warranted in this controversial area.

Adolescent↗
PubMed2003

Early intervention for relapse in schizophrenia: results of a 12-month randomized controlled trial of cognitive behavioural therapy.

BACKGROUND: The paper describes a randomized controlled trial of targeting cognitive behavioural therapy (CBT) during prodromal or early signs of relapse in schizophrenia. We hypothesized that CBT would result in reduced admission and relapse, reduced positive and negative symptoms, and improved social functioning. METHOD: A total of 144 participants with schizophrenia or a related disorder were randomized to receive either treatment as usual (TAU) (N = 72) or CBT+TAU (N = 72). Participants were prospectively followed up between entry and 12 months. RESULTS: At 12 months, 11 (15.3%) participants in the CBT group were admitted to hospital compared to 19 (26.4%) of the TAU group (hazard ratio = 0.53, P = 0.10, 95% CI 0.25, 1.10). A total of 13 (18.1%) participants in CBT relapsed compared to 25 (34.7%) in TAU (hazard ratio = 0.47, P < 0O05, 95% CI 0.24, 0.92). In addition, the CBT group showed significantly greater improvement in positive symptoms, negative symptoms, global psychopathology, performance of independent functions and prosocial activities. CONCLUSIONS: The study provides evidence for the feasibility and effectiveness for targeting CBT on the appearance of early signs of relapse in schizophrenia. The results are discussed in context of the study's methodological limitations.

Cognitive Behavioral Therapy↗
PubMed1986

Cefuroxime versus ampicillin plus chloramphenicol in childhood bacterial meningitis: a multicenter randomized controlled trial.

In a multicenter randomized trial, 107 children with bacterial meningitis were initially given either cefuroxime or ampicillin plus chloramphenicol. Patients were alternately assigned to 7- or 10-day courses of the designated antimicrobial regimen. CSF isolates included Haemophilus influenzae type b (89, of which 25% were beta-lactamase positive), Streptococcus pneumoniae, and Neisseria meningitidis. Although mean CSF bactericidal titers against Haemophilus isolates were 1:6 in each treatment group, H. influenzae was cultured from CSF in four of 39 patients receiving cefuroxime, 24 to 48 hours after initiation of therapy, compared with none of 40 patients given ampicillin plus chloramphenicol (P = 0.11). Clinical cure rates were similar (95%); one death occurred in each group. One child given cefuroxime had persistent meningitis after 5 days of therapy, and mastoiditis with secondary bacteremia developed in one on day 10. Three patients had relapse or reinfection. One patient who received cefuroxime for 10 days had a relapse of epiglottitis 17 days later, and of the patients given ampicillin plus chloramphenicol, one had a relapse of meningitis 1 week after 7 days of therapy, and bacteremia developed in one 42 days after completion of 10 days of therapy. No increase in either in-hospital complications or relapses occurred with a 7-day treatment course. Proof of the equivalence of the antibiotic regimens and the efficacy of 7-day courses of treatment, as well as the consequences of delayed CSF sterilization, will require additional investigation.

Adolescent↗
PubMed2002

Randomized controlled trial with low-dose spiral CT for lung cancer screening: feasibility study and preliminary results.

PURPOSE: To assess the feasibility of conducting a randomized controlled trial for lung cancer screening. MATERIALS AND METHODS: Subjects are being recruited into a randomized controlled trial to undergo either low-dose spiral computed tomography (CT) or observation. Subjects are from a high-risk group with known chronic obstructive pulmonary disease and sputum atypia and a moderate-risk group randomly selected from the general population of a Veterans Affairs Medical Center. All subjects must be 50-80 years of age with 30 or more pack-years of cigarette smoking and must not have undergone chest CT during the previous 3 years. Baseline screening CT is performed with 50 mA, 120 kVp, 5-mm collimation, and a pitch of 2. CT scan interpretation and management of nodules is based on Society of Thoracic Radiology guidelines. The chi(2) test for categoric data was used for statistical analysis. RESULTS: To date, 304 eligible subjects have been contacted, and 239 (79%) have agreed to participate in the trial. One hundred nineteen (88%) of the 136 subjects in the high-risk group and 120 (71%) of the 168 subjects in the moderate-risk group agreed to randomization (P <.001). To date, 190 subjects have been randomized. Of the first 92 subjects examined with CT, 22 (40%) of 55 in the high-risk group and eight (22%) of 37 in the moderate-risk group had one to six noncalcified nodules that required follow-up (P =.07). In all but three subjects, nodules were smaller than 5 mm. Two of the three larger nodules were malignancies. CONCLUSION: Findings of this study indicate that a randomized controlled trial of CT to screen for lung cancer is feasible.

Aged↗
PubMed2003

Randomized controlled trials in pediatric surgery: could we do better?

BACKGROUND/PURPOSE: Randomized controlled trials (RCTs) are accepted as the gold standard for assessing the effectiveness of clinical interventions but are rarely reported in pediatric surgery. Have RCTs submitted to the British Association of Paediatric Surgeons (BAPS) Annual Congress during the last 5 years been adequately designed and large enough to produce a valid result? METHODS: Abstracts accepted by the Annual BAPS Congress meetings between 1996 and 2000 were examined in collaboration with a senior health services researcher. The quality of the design, methodology, statistical analysis and conclusions, and the adequacy of the sample size were assessed for all identifiable clinical RCTs. RESULTS: From 760 accepted abstracts, there were only 9 RCTs (1%) of clinical interventions. In only 4 trials was the relevant primary end-point specified at the outset of the study, and none documented the method of randomization. Only one abstract mentioned blinding with respect to the intervention or outcome measure. Sample sizes were inadequate to detect even large clinical differences. To date, only one of these RCTs has been published in an English-language, peer-reviewed journal. CONCLUSIONS: Clear guidelines exist for the conduct of RCTs, yet compliance with these standards was rarely documented in abstracts of pediatric surgical RCTs presented at BAPS. Sample sizes were inadequate. RCTs in pediatric surgery are difficult to perform, but the specialty would benefit from well-designed, carefully conducted, multicentre, clinical RCTs to advance evidence-based practice.

Bibliometrics↗