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At least 613 records · Page 34Linked to original sources
PubMed2002

A pilot study to investigate the combined use of botulinum neurotoxin type a and functional electrical stimulation, with physiotherapy, in the treatment of spastic dropped foot in subacute stroke.

The objective was to inform sample size calculations for a full randomized controlled trial (RCT). The design included an RCT pilot trial with a 16 week study period, including a 4 week baseline phase. The subjects were adults within 1 year of first stroke, ambulant with a spastic dropped foot. Twenty-one participants were recruited from the stroke services of 4 centers. For intervention all participants received physiotherapy; the treatment group also received botulinum neurotoxin Type A (BoNTA) intramuscular injections to triceps surae (800 U Dysport) and functional electrical stimulation (FES) of the common peroneal nerve to assist walking. The main outcome measure was walking speed. The result was a significant upward trend in median walking speed for both the control (p = 0.02) and treatment groups (nonstimulated p = 0.004, stimulated p = 0.042). Trend lines were different in location (p = 0.04 and p = 0.009, respectively). In conclusion, there is evidence of an additional, beneficial effect of BoNTA and FES. Sufficient information has been gained on the variability of the primary outcome measure to inform sample size calculations for a full RCT to quantify the treatment effect with precision.

Adult↗
PubMed2001

Methodology standards associated with quality reporting in clinical studies in pediatric surgery journals.

BACKGROUND/PURPOSE: Reports of clinical trials often lack adequate descriptions of design and analysis; recent attention has focused on improving this omission so readers can properly assess the strength of the findings and draw their own conclusions. Similar analysis of study design and methodologic standards associated with quality reporting has not been carried out for pediatric surgery journals. METHODS: All studies (n = 642) published in 1998 in Journal of Pediatric Surgery (JPS) and Pediatric Surgery International (PSI), were reviewed for demographic data and study design. The frequency of reporting of 11 basic elements of design and analysis was evaluated in randomized clinical trials (RCT), nonrandomized clinical trials (NRCT), and retrospective cohorts (RC) from JPS by consensus of 2 assessors. RESULTS: Of the 642 studies, 17% of articles (111 of 642) were classified as clinical studies. Sixty-three were comparative studies and consisted of RC (n = 48), NRCT (n = 12), and RCT (n = 3). Two-thirds of articles published were either case reports or case series (431 of 642), and 16% were basic science articles. Demographic analysis showed a wide range of topics addressed, 4 authors per article, and multiple country of origin of authors. More than 66% of all RCT in JPS reported on eligibility criteria, admission before allocation, random allocation, method of randomization, patients' blindness to treatment, treatment complications, statistical analyses, statistical methods, loss to follow-up, and statistical methods; 2 elements of design and analysis, however, were poorly reported: blind assessment of outcome (33%) and power (17%). CONCLUSIONS: There were few randomized, controlled trials in pediatric surgery journals, and further attention should be given to evaluate the causal factors. Nine elements of quality reporting were well reported; however, 2 others were poorly reported; this may improve if editors of pediatric surgical journals provide authors with guidelines on how to report clinical trial design and analysis.

Authorship↗
PubMed2001

Indications for red cell transfusion in sickle cell disease.

Transfusion of red blood cells is an important therapeutic method employed in the care of people with sickle cell disease (SCD). There are several clinical situations in which patients with SCD clearly need red cell transfusion (RCT). In other situations, the indication for RCT is doubtful, controversial, or III-advised. RCT is used on either an episodic or chronic basis in the management of SCD. Episodic transfusions are usually applied in a patient who has already developed a serious complication of SCD or are used to reduce the chances for the development of a complication. Chronic transfusion therapy is often used to prevent the recurrence of a major complication such as a stroke. Recently, chronic transfusion has been applied to patients with evidence of cerebrovascular disease to prevent the first occurrence of stroke.

Anemia, Sickle Cell↗
PubMed2002

The before/after study design in transfusion medicine: methodologic considerations.

To ascertain the effectiveness of an intervention, a randomized controlled trial (RCT) is considered the gold standard. An obstacle to conducting an RCT only rarely discussed is the universal implementation of an intervention. Universal implementation clearly precludes the feasibility of conducting an RCT. Thus, the most attractive alternative study design in such instances becomes the before/after study. This article describes important methodologic considerations in undertaking a before/after evaluation. The methodologic considerations to be discussed are (1) threats to internal validity, (2) precision and (3) generalizability. Two before/after studies evaluating the potential effectiveness of universal leukoreduction serve as examples. Because of the universal application of many transfusion interventions, one has to consider carefully the methodologic rigor as to which of these interventions are evaluated. We have outlined the major methodologic issues one must consider when undertaking a before/after study design. When properly conceived, conducted, and analyzed, such a before/after study design can yield informative associations.

Adult↗
PubMed2003

Predictors of short-term and long-term memory of sensory and affective dimensions of pain.

The purpose of this investigation was to establish predictors of the dimensions of pain intensity and pain unpleasantness recalled at 1 week and 18 months after an invasive therapeutic procedure, root canal therapy (RCT). Pretreatment measures of mood state and RCT-related expectations of sensory and affective dimensions of pain by using a visual analog scale (VAS) format were obtained. VAS measures of experienced pain intensity and unpleasantness were obtained immediately after treatment. Patients[apos ] memory of their RCT-related pain intensity and unpleasantness was assessed by phone call. Regression analysis showed that after controlling for age, experienced pain intensity predicts 1-week memory of pain intensity (adjusted R(2) [equals].34, P [lt ].01), whereas patients[apos ] pretreatment affective state predicts the memory of pain intensity at 18 months (adjusted R(2) [equals].24, P [lt ].01) and the memory of pain unpleasantness at 1 week (adjusted R(2) [equals].40, P [lt ].01) and 18 months (adjusted R(2) [equals].62, P [lt ].01). These findings point to the contribution of preexisting affective state to the sensory and affective dimensions of pain recollection and illustrate the importance of anxiety management for minimizing patient[apos ]s long-term recollection of the aversiveness of outpatient medical and dental procedures.

Adult↗
PubMed1996

Study design for the evaluation of treatment.

Study design is a critical step in clinical research. Such studies may be either randomized or nonrandomized; the latter may be retrospective or prospective. Nonrandomized designs include surveys and observational studies. The randomized clinical trial (RCT) is an experimental design, with patients randomly allocated to treatment arms. A number of designs are possible. These include the simple experiment, repeated measure design, crossover study, and factorial design. Issues in clinical trials include subject inclusion/exclusion criteria, control group treatment, blinding, compliance, sample size, treatment assignment, and subject withdrawal. Disadvantages of the RCT include cost and the lack of true clinical equipoise. It is also worth noting that the RCT is not infallible. Patients should be analyzed based not on their compliance but rather on an intent-to-treat basis.

Clinical Trials as Topic↗
PubMed1995

Chicken lecithin-cholesterol acyltransferase. Molecular characterization reveals unusual structure and expression pattern.

Rapidly growing oocytes in the laying hen are, in addition to the liver, targets of the so-called "reverse cholesterol transport" (RCT) (Vieira, P.M., Vieira, A.V., Sanders, E.J., Steyrer, E., Nimpf, J., and Schneider, W.J. (1995) J. Lipid Res. 36, 601-610), pointing to the importance of this process in nonplacental reproduction. We have begun to delineate the details of this unique transport pathway branch by molecular characterization of the first nonmammalian lecithin-cholesterol acyltransferase (LCAT), the enzyme that catalyzes an early step in RCT. The biological significance of the enzyme is underscored by the high degree of protein sequence identity (73%) maintained from chicken to man. Interestingly, the conservation extends much less to the cysteine residues; in fact, two of the cysteines thought to be important in mammalian enzymes (residues 31 and 184 in man) are absent from the chicken enzyme, providing proof of their dispensability for enzymatic activity. Antibodies prepared against a chicken LCAT fusion protein cross-react with human LCAT and identify a 64-kDa protein present in enzymatically active fractions obtained by hydrophobic chromatography of chicken serum. The developmental and tissue distribution pattern of LCAT in females is striking; during embryogenesis and adolescence, LCAT expression is extremely high in liver but undetectable in brain. Upon onset of laying, however, brain LCAT mRNA increases suddenly and is maintained at levels 5 times higher than in liver, in stark contrast to most mammals. In adult roosters, the levels of LCAT transcripts in brain are lower than in liver. Together with the molecular characterization of chicken LCAT, these newly discovered developmental changes and gender differences in its expression establish the avian oocyte/liver system as a powerful model to delineate in vivo regulatory elements of RCT.

Amino Acid Sequence↗
PubMed2003

Physical activity interventions in the prevention and treatment of paediatric obesity: systematic review and critical appraisal.

Interventions for prevention and treatment of childhood obesity typically target increases in physical activity and, more recently, reductions in physical inactivity (sedentary behaviour such as television viewing). However, the evidence base for such strategies is extremely limited. The main aim of the present review was to update the systematic review and critical appraisal of evidence in the light of the recent rapid expansion of research in this area. Randomised controlled trials (RCT) that targeted activity or inactivity, that followed up children or adolescents for at least 1 year and that included an objective weight-related outcome measure were included. Trials were appraised using previously published criteria (Harbour & Miller, 2001), and literature search strategies described previously (Reilly et al. 2002) were updated to May 2002. A total of four new RCT, two new systematic reviews and one meta-analysis were identified. The evidence base has increased markedly since the completion of earlier reviews, although high-quality evidence is still lacking. The evidence on childhood obesity prevention is not encouraging, although promising targets for prevention are now clear, notably reduction in sedentary behaviour. There is stronger evidence that targeting activity and/or inactivity might be effective in paediatric obesity treatment, but doubts as to the generalisability of existing interventions, and the clinical relevance of the interventions is unclear. Further research in settings outside the USA is urgently needed, and two ongoing RCT in Scotland are summarised.

Adolescent↗
PubMed2006

Can pelvic floor muscle training prevent and treat pelvic organ prolapse?

BACKGROUND AND METHODS: Pelvic floor muscle dysfunction may cause urinary and fecal incontinence, pelvic organ prolapse (POP), pain, and sexual disturbances. The aim of the present study is to review the literature on the effectiveness of pelvic floor muscle training (PFMT) to prevent and treat POP, and the possible theories and mechanisms on how PFMT could prevent or reverse prolapse. RESULTS: No studies were found on prevention of POP. One uncontrolled study and one low-quality RCT were found in the treatment of prolapse. The results showed a positive effect of PFMT in severe, but not in mild prolapse. A review is presented of the main hypothesis of mechanisms on how PFMT may be effective. The two mechanisms are morphological changes occurring after strength training and use of a conscious contraction during increase in abdominal pressure in daily activities. CONCLUSIONS: In addition to the theory of functional anatomy and exercise science, one randomized controlled trial (RCT) is supportive for a positive effect of PFMT in the treatment of POP. There is an urgent need for more RCT with high methodological quality, use of valid and reproducible methods to assess degree of prolapse, and appropriate training protocols to evaluate the effect of PFMT in the prevention and treatment of POP.

Exercise Therapy↗
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↗
PubMed2003

CNS prophylaxis and treatment in non-Hodgkin's lymphoma: variation in practice and lessons from the literature.

Practices regarding central nervous system (CNS) prophylaxis and treatment for non-"high-grade" lymphomas are not standardized. We designed a survey to address the CNS surveillance, prophylaxis and treatment (S + P + T) habits of Ontario oncologists, to compare tertiary with community care and gauge interest in a randomized controlled trial (RCT). We mailed 145 questionnaires to oncologists/hematologists registered at the Royal College of Physicians and Surgeons of Ontario between 1980 and 1999. The questionnaire posed questions of S + P + T for a variety of histologies, locations and risk factors. Results showed that 49/77 respondents treated adult NHL, (19 community, 30 tertiary care). Surveillance LP's were commonly done in testicular, orbital, sinus and epidural sites of presentation (76, 69, 71, 80%, respectively), but these were less commonly prophylaxed (45, 33, 29 and 41%). HIV associated NHL received surveillance and prophylaxis by 51 and 33% of respondents. Stage IV disease, increased LDH and extranodal-sites warranted infrequent S + P. IT chemotherapy via LP was the most commonly used form of prophylaxis (74%) or treatment (84%). Twenty percent used systemic agents that cross the blood brain barrier for prophylaxis, and 45% for treatment. A vast heterogeneity of practice within and between tertiary care and community physicians' practices was documented. Ninety percent of physicians indicated willingness to participate in a RCT. In conclusion, CNS surveillance and prophylaxis in non-"high-grade" NHL is highly variable, probably because there are poorly defined risk factors, inconclusive prophylaxis efficacy and the inconvenience/toxicity of therapy. Patients at high risk by International prognostic index criteria are at an increased risk for CNS relapse. A RCT comparing standard chemotherapy with or without CNS prophylaxis in selected patients is needed.

Adult↗
PubMed2002

Recruitment of African Americans with type 2 diabetes to a randomized controlled trial using three sources.

OBJECTIVES: To assess the usefulness of three sources (faith-based organizations (FBOs), health system, and community) for recruitment of African Americans with type 2 diabetes to a randomized controlled trial (RCT). DESIGN: African Americans with type 2 diabetes were recruited to a diabetes self-management program at four FBO sites. An observational study of a multifaceted recruitment strategy to enroll subjects in the RCT that evaluated the effectiveness of a diabetes self-management program and the effect of recruitment source on retention after enrollment. Self-administered demographic surveys and weekly class attendance records were collected. RESULTS: Of 184 interested individuals, 109 (59.2%) were enrolled. Of those enrolled, 60.6% recruited through the health system, 13.8% FBOs, and 19.2% the community. The highest yield was achieved through the health system. However, for both the intervention (I) and control (C) groups, respectively, participants recruited from FBOs (85.7% I; 62.5% C) were more likely to attend four or more sessions than those from the health system (75.0% I; 43.3% C) and community (55.6% I; 25.0% C). Despite similar class size, participants in the intervention group (74.5%; n = 41) were more likely to attend four or more of the seven classes than those in the delayed intervention (control group) (40.7%; n = 22). CONCLUSIONS: The findings suggest that African American adults with diabetes can be successfully recruited and retained in a racially targeted RCT conducted in FBOs. Key elements to consider are the use of a multifaceted approach for participant recruitment, particularly the benefit of health system physician involvement in recruitment since the highest yield was achieved through health system providers, and importance of site location for retention.

Adult↗
PubMed1989

Development of a field method for evaluating the service life of organic vapor cartridges: results of laboratory testing using carbon tetrachloride.

A new method for determining the service life of respirator cartridges has been developed and tested in a laboratory setting. The method involves using small respirator carbon tubes (RCTs) packed with sorbent obtained from a respirator cartridge of interest. The tubes may be taken into an industrial setting and used to evaluate the work environment. A sample tube is placed directly behind the RCT and periodically replaced. This tube acts as a backup section to the RCT. The sample tube can be brought back to a laboratory and analyzed for the contaminant of interest using validated sampling methods specific for the contaminant. Alternatively, a direct-reading instrument can be placed at the exit end of the RCT to obtain "real-time" breakthrough information. The results, when combined with existing sorbent theories, can be used to predict the service life of a respirator cartridge. The advantage of using RCTs is that, unlike respirator cartridges, they can be taken into the field and used with traditional high-flow air sampling pumps. This method is designed to be able to determine the service life of respirator cartridges even when multiple contaminants are present in the workplace. Results of initial laboratory studies, using carbon tetrachloride as a challenge agent, indicated that RCTs were capable of predicting cartridge service life within an accuracy of +/- 15%.

Carbon Tetrachloride↗
PubMed2001

Questionnaires for a randomized controlled trial methodology to evaluate the teaching utility of diabetes simulation programs.

AIDA is an interactive educational diabetes simulator which has been made available without charge on the Internet. Since its launch on the World Wide Web in 1996 over 87,000 people have visited the AIDA Website--http://www.2aida.org--and over 22,000 copies of the program have been downloaded from there free-of-charge. The AIDA software is believed to be of use in recreating clinically realistic diabetes situations for interactive simulation. However, despite its widespread application, its actual utility for supporting the education of patients with type 1 diabetes mellitus remains to be objectively demonstrated in a clinical randomised controlled trial (RCT) setting. The current "Diabetes Information Technology & WebWatch" column overviews a prospective RCT methodology for formally evaluating the educational utility of an interactive diabetes simulator, like AIDA. The protocol makes use of two study arms--each receiving different educational interventions. During lessons, arm A of the study will be exposed to the AIDA simulator (the active intervention), while arm B (the control group) will benefit from conventional educational methods using standard presentations with slides and transparencies. Six lessons will be held for each study arm (one per week). At the beginning and end of the study self-monitoring blood glucose (SMBG) data will be collected, details of any hypoglycemic episodes recorded, and assessments made of glycosylated hemoglobin (HbA1c) levels. Participants will also be required to complete a detailed questionnaire to assess their self-confidence, quality of life and metabolic control, attitudes towards SMBG, and knowledge about insulin dosage calculation. Comparisons will be made between arm A and arm B using unpaired statistical analyses. A partial cross-over study design is also proposed whereby subsequently the control group will be exposed to the AIDA simulator during a further 6-week course of lessons. This will ensure that the maximum number of subjects will eventually receive the active intervention, and will also allow further within group paired analyses to be applied (with greater statistical power). This current "Diabetes Information Technology & WebWatch" column documents two of the questionnaires which are intended to be used for this RCT approach.

Computer Simulation↗
PubMed1996

Methodological issues in complementary and alternative medicine research: a personal reflection on 10 years of debate in the United Kingdom.

There are certain immediate and obvious problems in using conventional research techniques for the evaluation of complementary and alternative medicine (CAM). These have led some to argue that alternative medicine requires alternative methodologies. The experience in the United Kingdom has been that existing methodologies can be adapted and do not have to be discarded wholesale. Conventional research has developed a set of powerful techniques for generating reliable knowledge and these have been used with considerable success in a variety of different settings. In retrospect, the call for new methodologies appears to have been a reaction against the perceived dominance of the randomized controlled trial (RCT). This stemmed from the misperception that the RCT inevitably involves features, such as placebo controls or double-blinding, which are not feasible in many CAM therapies. There was also a desire to ask questions about medicine, the answers to which, it was felt, could not be decided by the RCT. A variety of different research designs need to be used to answer the variety of questions important in CAM. However, research designs do not have to be reinvented: appropriate methodologies can normally be found in one or another of the diverse branches of medical research. Successful research has been conducted in CAM using conventional research techniques and this refutes the claims that such techniques are inappropriate for CAM. Solving methodological problems in CAM is a matter of following simple guidelines, not the creation of complex and esoteric research designs.

Complementary Therapies↗
PubMed2000

Clinical evidence of subcutaneous CO2 insufflations: a systematic review.

OBJECTIVE: To evaluate the evidence of clinical effectiveness of subcutaneous CO2 insufflations (SCIs). STUDY LOCATION: The entire databases of MEDLINE, EMBASE Excerpta Medica (Field: Rehabilitation and Physical Medicine) and the Cochrane Library were screened for data up to August 1999. In addition, other potentially relevant journals were handsearched and references were checked. STUDY SELECTION: Uncontrolled observational trials (UCOTs) with sample sizes of at least n = 100, and controlled clinical trials (CCTs) and randomized controlled trials (RCTs) were included. Outcomes had to be patient-centered. English-, Czechoslovakian-, and German-language papers were considered. DATA ANALYSIS: For all study types, a criteria-based analysis was performed. For controlled trials only, quality was quantitatively assessed with the Jadad and Maastricht Scales. RESULTS: Thirteen studies (5 RCTs, 2 CCTs, and 6 UCOTs) were included. Mean scores on the Jadad and Maastricht Scales were 2 (Maximum 5) and 37 (Maximum 100), respectively. SCIs were found to be effective in addition to standard physical therapy in "peripheral arterial occlusive disease" (2 RCTs) and "stable angina pectoris" (1 RCT) and superior to sham needling for migraine headaches (1 RCT). There were no differences among SCIs and CO2 gas baths (1 RCT) or combined interventions, including SCIs (2 CCTs). All 6 UCOTs showed marked longitudinal effects. CONCLUSIONS: The low number and quality of the available studies precludes firm conclusions on the clinical effectiveness of SCIs.

Carbon Dioxide↗
PubMed1996

Randomization is important in studies with pain outcomes: systematic review of transcutaneous electrical nerve stimulation in acute postoperative pain.

We set out to examine the evidence for the importance of randomization of transcutaneous electrical nerve stimulation (TENS) in acute postoperative pain. Controlled studies were sought; randomization and analgesic and adverse effect outcomes were summarized. Forty-six reports were identified by searching strategies. Seventeen reports with 786 patients could be regarded unequivocally as randomized controlled trials (RCT) in acute postoperative pain. No meta-analysis was possible. In 15 of 17 RCT, we judged there to be no benefit of TENS compared with placebo. Of the 29 excluded trials, 19 had pain outcomes but were not RCT; in 17 of these 19 TENS studies, the authors concluded that TENS had a positive analgesic effect. No adverse effects were reported. Non-randomized studies overestimated treatment effects.

Acute Disease↗
PubMed2001

Referrals and relationships: in-practice referrals meetings in a general practice.

BACKGROUND: GP referrals to secondary care are an important factor in the cost of running the NHS. The known variation in referral rates between doctors has the potential to cause tension within primary care which will be exacerbated by the latest reorganization of primary care and the trend towards capitation-based budgets. The importance of postgraduate learning for GPs has been recognized; continuing professional development is moving towards self-directed practice-based learning programmes. Educational interventions have been shown to alter doctors' prescribing behaviour. This, together with the pressure on accounting for referral activity, makes the prospect of improving, and possibly reducing, referral activity through educational interventions very attractive. OBJECTIVES: This study complemented a randomized controlled trial (RCT) which investigated whether an intervention of the type which had reduced prescribing costs would have a similar effect on referral activity. METHODS: The context of the study, description of the characteristics of the practice and the issues seen as important by the doctors and practice manager were identified through preliminary semi-structured interviews. The practice then held a series of educational in-practice meetings to discuss referrals and issues arising from referrals. The audio- and videotaped transcripts were interpreted using content and group dynamic analysis. Participants commented upon our preliminary findings. In addition, we used dimensional analysis to induce a preliminary theory describing the effect of the intervention on this general practice which enabled us to review the findings of the parallel RCT. The educational value of the meetings and the learning needs of the participants were also assessed. RESULTS: Our complementary study showed no alteration of practice referral rates following the educational intervention. The qualitative study, unencumbered by the assumptions inherent in the development of the hypothesis tested in the RCT, highlighted the complexity of decision making in general practice and the likely impact of historical background and a variety of internal and external pressures on this self-directive educational intervention. The practice members described the individual and group learning needs identified as a result of the meetings. CONCLUSION: The findings of this study raise important questions for developing practice-based learning. The outcomes of self-directive interventions in practices will be influenced by internal and external events both past and present. Such outcomes may be qualitative and difficult to measure. They are likely to differ from outcomes seen when interventions are applied to groups of doctors who are not all members of the same practice.

Family Practice↗