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PubMed2002

Issues in conducting randomized controlled trials of health services research interventions in nonacademic practice settings: the case of retail pharmacies.

OBJECTIVE: To describe unexpected challenges and strategies to overcome them when conducting randomized controlled trials (RCT) of health services research interventions in retail pharmacies. STUDY SETTING: Thirty-six retail drug stores in Indianapolis. STUDY DESIGN: We conducted an RCT to evaluate the effectiveness of an intervention to increase pharmacists' involvement in caring for customers. We describe: (1) our RCT as originally designed, (2) unexpected challenges we faced; and (3) how we resolved those challenges. DATA COLLECTION/EXTRACTION METHODS: Randomized controlled trial. PRINCIPAL FINDINGS: Major modifications in research design were necessitated by factors such as corporate restructuring, heightened sensitivity to patient confidentiality, and difficulties altering employees' behavior. We overcame these barriers by conducting research that is consistent with corporate goals, involving appropriate corporate administrators and technical personnel early in the process, and being flexible. CONCLUSIONS: Health services researchers should conduct RCTs in a variety of non-academic practice settings to increase generalizability and better reflect the true impact of interventions. Pragmatic problems, although significant, can be successfully overcome.

Adolescent↗
PubMed1989

An introduction to survival analysis: statistical methods for analysis of clinical trial data.

The randomized controlled clinical trial (RCT) is a prospective study using random assignment of subjects to treatment groups to compare the effect and value of a therapeutic intervention against a control. The RCT is the most definitive clinical research tool for evaluating the efficacy of a new therapy in human subjects. Often the outcome of interest in an RCT is the length of time until an event occurs after treatment or intervention. In this article we introduce statistical methods for evaluating differences in the patterns of time to response between two groups of subjects to determine whether one therapy is better than another. The collection of methods for analyzing such data, known as survival data, is called survival analysis. Using data from a hypothetical clinical trial for the prevention of the recurrence of depression, we illustrate two elementary methods for analyzing survival data. We also discuss generalizations of these methods to incorporate covariates and conclude with a general discussion of clinical trials of psychiatric therapies.

Clinical Trials as Topic↗
PubMed1992

Comparative efficacy of religious and nonreligious cognitive-behavioral therapy for the treatment of clinical depression in religious individuals.

Two versions of cognitive-behavioral therapy (CBT), one with religious content (RCT) and one with standard protocol (NRCT), were used to treat 19-20 religious patients each. Fifty-nine religious patients who met the Research Diagnostic Criteria for nonpsychotic, nonbipolar depression were treated in 18-20 1-hr sessions over 3 months. Religious and nonreligious therapists were used in each CBT group. Pastoral counseling (PCT) treatment-as-usual and waiting-list control (WLC) conditions each contained 10-11 patients. RCT and PCT patients reported significantly lower posttreatment depression and adjustment scores than did either the NRCT or the WLC condition. The CBT difference was due largely to superior performance of the nonreligious therapists (with dissimilar values to the patients) in the RCT over the NRCT condition. Improvement in the three treatment conditions was equal at 3-month and 2-year follow-ups and greater than posttreatment WLC improvement levels.

Adaptation, Psychological↗
PubMed1986

Behavioral interventions for childhood nocturnal enuresis: the differential effect of bladder capacity on treatment progress and outcome.

Study participants were fifty 5- to 13-year-old children (33 boys and 17 girls) with nocturnal enuresis of at least 3 months duration. All wet their beds at least twice per week, were of normal intelligence, and were without demonstrable organic cause for their enuresis. Each youngster's pretreatment maximum functional bladder capacity (MFBC) was used to classify the child as having small or large MFBC based on available norms. Youngsters were then randomly assigned to treatment with the urine alarm (UA) alone or with the urine alarm supplemented with retention control training (UA plus RCT). Of the 40 youngsters who completed treatment, 37 (92.5%) achieved the treatment goal of 14 consecutive dry nights. Two additional children became dry during follow-up, leaving only one child who failed to stop wetting. Sixteen children (41%) subsequently relapsed, but all who reentered treatment became dry. Because treatment outcome was uniformly excellent across all groups, treatment progress was evaluated by analyzing wetting frequency and arising at night to use the bathroom during treatment, as well as prechange and postchange in MFBC For both wetting frequency and arising at night, there was a significant interaction between bladder capacity and treatment. Small MFBC children treated with the UA plus RCT and large MFBC youngsters treated with the UA alone had the fewest wetting episodes and got up at night to use the bathroom less often; these youngsters took less time to be successfully treated. Prechanges and postchanges in MFBC indicated that RCT did not lead to consistent increases in bladder capacity in the sample studies. The 10 children who terminated treatment prematurely had lower self-esteem and more parent-reported conduct problems than the 40 children who completed treatment.

Adolescent↗
PubMed2003

Are samples in randomized controlled trials of psychotherapy representative of community outpatients? A new methodology and initial findings.

To determine the extent to which published randomized controlled trials (RCTs) of psychotherapy can be generalized to a sample of community outpatients, the authors used a method of matching information obtained from outpatient charts to inclusion and exclusion criteria from published RCT studies. They found that 80% of the patients in their sample who had diagnoses represented in the RCT literature were judged eligible for at least 1 published RCT; however, 58% of the patients had primary diagnoses such as adjustment disorder or dysthymia, which were not represented in the existing psychotherapy outcome literature. The most common reasons that patients in their sample did not match with published RCTs for psychotherapy are listed, and the implications of these findings for research and practice are discussed.

Adult↗
PubMed2005

Can the randomized controlled trial literature generalize to nonrandomized patients?

To determine the extent to which published randomized controlled trials (RCTs) of psychotherapy can be generalized to a sample of outpatients, the authors matched information obtained from charts of patients who had been screened out of RCTs to inclusion and exclusion criteria from published RCT studies. Most of the patients in the sample who had primary diagnoses represented in the RCT literature were judged eligible for at least 1 RCT. However, many patients in the sample with substance use disorders or social anxiety disorder were not eligible for at least 2 RCTs. Common reasons that patients did not match with at least 2 published RCTs for psychotherapy included (a) patients were in partial remission, (b) patients failed to meet minimum severity or duration criteria, (c) patients were being treated with antidepressant medication, and (d) the disorder being studied was not primary (mostly for social anxiety patients). The implications of these findings for future research and clinical practice are discussed.

Adult↗
PubMed1999

Follow-up of breast cancer in primary care vs specialist care: results of an economic evaluation.

A randomized controlled trial (RCT) comparing primary-care-centred follow-up of breast cancer patients with the current standard practice of specialist-centred follow-up showed no increase in delay in diagnosing recurrence, and no increase in anxiety or deterioration in health-related quality of life. An economic evaluation of the two schemes of follow-up was conducted concurrent with the RCT Because the RCT found no difference in the primary clinical outcomes, a cost minimization analysis was conducted. Process measures of the quality of care such as frequency and length of visits were superior in primary care. Costs to patients and to the health service were lower in primary care. There was no difference in total costs of diagnostic tests, with particular tests being performed more frequently in primary care than in specialist care. Data are provided on the average frequency and length of visits, and frequency of diagnostic testing for breast cancer patients during the follow-up period.

Breast Neoplasms↗
PubMed2005

Grinding is effective in early orthodontic treatment of unilateral posterior crossbite.

DATA SOURCES: PubMed and the Cochrane Controlled Clinical Trials Register were searched. Reference lists from retrieved articles were also searched by hand for additional studies. STUDY SELECTION: For inclusion, an article had to satisfy the following criteria: cases in primary and early mixed dentition with unilateral posterior crossbite; be a randomised controlled trials (RCT) or prospective and retrospective studies with concurrent untreated as well as normal controls; clinical trials must have compared at least two treatment strategies without any untreated or normal control group involved; and be written in English, German, French or a Scandinavian language. DATA EXTRACTION AND SYNTHESIS: Data extraction was carried out independently and in duplicate. Quality of the studies was assessed and categorised as low, medium and high. Interexaminer conflicts were resolved by discussion to reach a consensus. RESULTS: The search identified 1001 articles, of which 12 met the inclusion criteria. Only two RCT of early treatment of crossbite have been performed, and these two studies support grinding as treatment in the primary dentition. As treatment strategies, quad-helix (QH), expansion plates and rapid maxillary expansion (RME) are effective in the early mixed dentition with high success rates. There is, however, no scientific evidence available that shows which of the treatment modalities, that is, grinding, QH, expansion plates or RME, is the most effective. CONCLUSIONS: Most of the studies have the serious drawback of lack of power because of small sample size, bias and confounding variables, lack of method error analysis and blinding in measurements, and deficient or lack of statistical methods. Thus, the studies were not of high enough quality level to draw any evidence-based conclusions. Better-controlled RCT with sufficient sample sizes are needed to obtain reliable scientific evidence identifying which treatment is the most effective for early correction of unilateral posterior crossbite. Future studies should also include assessments of long-term stability as well as analysis of costs and side-effects of the interventions.

Comment↗
PubMed2006

Early treatment of skeletal open-bite malocclusion.

DATA SOURCES: Studies were identified by searching the Cochrane Controlled Clinical Trials Register and Medline. STUDY SELECTION: Randomised clinical trials (RCT), prospective and retrospective studies that had concurrent untreated as well as normal controls, and clinical trials that compared at least two treatment strategies but did not have any untreated or normal control group were included. The following were excluded: case series; descriptive studies; case reports; studies concerning treatment in the permanent dentition/ adult patients, surgically assisted treatment, treatment combined with extractions, treatment with full-fixed appliances; and discussion or debate articles. DATA EXTRACTION AND SYNTHESIS: Year of publication, study design, materials, dropouts, measurements, treatment time, success rate, decrease of open bite and divergence, side effects, costs, and authors' conclusions were recorded. Two independent reviewers assessed the articles independently and a quality evaluation and qualitative summary were performed. RESULTS: A total of 1049 articles were identified of which seven were included in the review. No RCT of early treatment of anterior open bite have been performed. Two controlled clinical trials of early anterior open bite were identified, and these both indicated the effectiveness of treatment in the mixed dentition with headgear or functional appliances (or both). Most of the studies had serious problems with lack of power because of small sample size, bias and confounding variables; lack of method-error analysis or blinding in measurements; and deficient or lack of statistical methods. CONCLUSIONS: The quality of the studies was insufficient to allow any evidence-based conclusions to be drawn. RCT of sufficient sample size are still needed to determine which treatment is the most effective for early correction of skeletal open bite. Future studies should also include the assessment of long-term stability as well as an analysis of the cost and side-effects of the interventions.

Comment↗
PubMed2000

Long-lived adsorbate states on metal surfaces.

It has been shown recently that the peculiarities of the band structure of a metal can qualitatively influence the electron tunnelling between an adsorbate and a metal surface, the so-called resonant charge transfer (RCT). The presence of a projected band gap along the normal to the surface in the case of Cu(111) has been shown to lead to a blocking of the RCT in the case of Cs/Cu(111), resulting in the existence of a very long-lived excited state. Such long-lived states are potentially very important for surface reaction mechanisms invoking a transient state as an intermediate. Various systems: Cs, model M- negative ion of p pi symmetry, CO adsorbed on Cu(111), are investigated in order to determine the conditions for the blocking of the RCT and the existence of long-lived states.

Journal Article↗
PubMed2005

Effects of computer-based intervention through acoustically modified speech (Fast ForWord) in severe mixed receptive-expressive language impairment: outcomes from a randomized controlled trial.

Seventy-seven children between the ages of 6 and 10 years, with severe mixed receptive-expressive specific language impairment (SLI), participated in a randomized controlled trial (RCT) of Fast ForWord (FFW; Scientific Learning Corporation, 1997, 2001). FFW is a computer-based intervention for treating SLI using acoustically enhanced speech stimuli. These stimuli are modified to exaggerate their time and intensity properties as part of an adaptive training process. All children who participated in the RCT maintained their regular speech and language therapy and school regime throughout the trial. Standardized measures of receptive and expressive language were used to assess performance at baseline and to measure outcome from treatment at 9 weeks and 6 months. Children were allocated to 1 of 3 groups. Group A (n = 23) received the FFW intervention as a home-based therapy for 6 weeks. Group B (n = 27) received commercially available computer-based activities designed to promote language as a control for computer games exposure. Group C (n = 27) received no additional study intervention. Each group made significant gains in language scores, but there was no additional effect for either computer intervention. Thus, the findings from this RCT do not support the efficacy of FFW as an intervention for children with severe mixed receptive-expressive SLI.

Analysis of Variance↗
PubMed2000

Design issues for drug epidemiology.

Despite the difficulties involved in designing drug epidemiology studies, these studies are invaluable for investigating the unexpected adverse effects of drugs. The aim of this paper is to discuss various aspects of study design, particularly those issues that are not easily found in either textbooks or review papers. We have also compared and contrasted drug epidemiology with the randomized controlled trial (RCT) wherever possible. Drug epidemiology is especially useful in the many situations where the RCT is not suitable, or even possible. The study base has to be defined before the appropriate cohort of subjects is assembled. If all of the cases are identified, then a referent sample of controls may be assembled by random sampling of the study base. If all of the cases cannot be assembled, a hypothetical secondary base may need to be created. Preferably, only new-users of the drug should be included, and the risk-ratio will be different for acute users and chronic users. Studies will usually only be possible when researching the unintended effects of drugs. It is difficult to study efficacy because of confounding by indication. In occasional circumstances it may be possible to study efficacy (examples are given). Discussion of the dangers of designing with generalisability in mind is provided. Additionally, the similarities in study design between drug epidemiology and the RCT are discussed in detail, as well as the design-characteristics that cannot be shared between the two methods.

Cohort Studies↗
PubMed2002

A review of physical restraint minimization in the acute and residential care settings.

OBJECTIVES: The objective of this review was to investigate physical restraint minimization in acute and residential care settings. The first aim was to determine the effectiveness of attempts to minimize the use of physical restraint, and the second was to generate a description of the characteristics of restraint minimization programmes. METHOD: A comprehensive search was undertaken involving all major databases and the reference lists of all relevant papers. To be included in the review studies had to be an evaluation of restraint minimization in an acute or residential care setting. As only a single randomized controlled trial (RCT) was identified, it was not possible statistically to pool the findings of different studies on the effectiveness of restraint minimization. To generate a description of the characteristics of restraint minimization programmes, the reported components of these programmes were identified and categorized. RESULTS: A total of 16 studies evaluating restraint minimization were identified: three in acute care and 13 in residential care. Of these, only one was an RCT, with the most common approach being the before and after study design. Based on the findings of the single RCT, education supported by expert consultation effectively reduced the use of restraint in residential care. There has been little evaluation of restraint minimization in acute care settings. The common approach to restraint minimization has involved a programme of multiple activities, with restraint education being the characteristic common to most programmes. DISCUSSION: Evidence suggests that physical restraint can be safely reduced in residential care settings through a combination of education and expert clinical consultation. There is little information on restraint minimization in acute care settings. The major finding of this review is the need for further investigation into all aspects of restraint minimization.

Accidental Falls↗
PubMed2002

At what degree of belief in a research hypothesis is a trial in humans justified?

RATIONALE, AIMS AND OBJECTIVES: Randomized controlled trials (RCTs) have emerged as the most reliable method of assessing the effects of health care interventions in clinical medicine. However, RCTs should be undertaken only if there is substantial uncertainty about which of the trial treatments would benefit a patient most. The purpose of this study is to determine the degree of uncertainty in a research hypothesis before it can empirically be tested in an RCT. METHODS: We integrated arguments from three independent lines of research - on ethics, principles of the design and conduct of clinical trials, and medical decision making - to develop a decision model to help solve the dilemma of under which circumstances innovative treatments should be tested in an RCT. RESULTS: We showed that RCTs are the preferable option to resolve uncertainties about competing treatment alternatives whenever we desire reliable, undisputed, high-quality evidence with a low likelihood of false-positive or false-negative results. CONCLUSIONS: When the expected benefit:risk ratio of a new treatment is small, an RCT is justified to resolve uncertainties over a wide range of prior belief (e.g. 10-90) in the accuracy of the research hypothesis. Randomized controlled trials represent the best means for resolving uncertainties about health care interventions.

Decision Support Techniques↗
PubMed2002

Developmental outcome of preterm infants after surfactant therapy: systematic review of randomized controlled trials.

OBJECTIVES: To review neuro-developmental outcome at 1 and 2 years of age following randomized controlled trials (RCT) of neonatal surfactant therapy. METHODS: A systematic review of the MEDLINE, Embase and Cochrane Controlled Trial Register databases, searching for RCT of surfactant replacement therapy with follow-up outcomes, was carried out. The main outcome measures were severe and mild disability at 1 and 2 years plus composite adverse outcome of death and/or severe disability. RESULTS: A meta-analysis using odds ratios was carried out on 13 RCT. There were a total of 2218 treated and 2090 control infants who underwent follow up at 1 year of age. There were 303 treated and 292 control infants with follow up at between 18 months and 2 years of age. Surfactant therapy was associated with a lower rate of mild disability at 1 year (OR 0.79; 95% CI 0.66-0.95). There was a reduction in the combined adverse outcome (death or severe disability rate) at 1 year (OR 0.8; 95% CI 0.72-0.89). Neither the 1 year nor the 2 year follow-up examination showed a statistical difference in the severe disability rate between the control and treated group. CONCLUSION: Surfactant therapy increases survival without an increase in subsequent morbidity at 1 and 2 years of age.

Child, Preschool↗
PubMed2002

Discrepancies in nutritional recommendations: the need for evidence based nutrition.

The widespread acceptance that 'evidence-based medicine' should determine all aspects of clinical practice leads to a consideration as to whether 'evidence-based nutrition' should be based on similar principles. Randomised controlled trials (RCT) are universally regarded as the gold standard by which to determine whether a drug is appropriate in a particular clinical situation. The evidence for some nutritional recommendations is indeed substantiated by RCT but in the case of some chronic diseases, notably cancers, where nutritional factors may operate as promoters or protectors many years before the onset of clinical disease, RCT may not be particularly appropriate. A range of experimental studies and descriptive epidemiological approaches may be regarded as sufficient to justify nutritional recommendations or dietary guidelines. Recommendations for the prevention and treatment of selected diseases will be considered in the context of their evidence-base.

Chronic Disease↗
PubMed2001

Renoprotection: one or many therapies?

BACKGROUND: Renal disease that progresses to end-stage renal disease (ESRD) imposes a great burden on the affected individual and on society, which mainly bears the cost of ESRD (currently more than $10 billion to treat about 333,000 patients annually in the U.S.). Thus, there is a great need to identify therapies that arrest the progression mechanisms common to all forms of renal disease. Progress is being made. Perhaps the most visible advance is the randomized controlled trials (RCT) demonstrating the renoprotective effects of angiotensin-converting enzyme (ACE) inhibitors. There are also numerous other promising renoprotective therapies. Unfortunately, testing each therapy in RCT is not feasible. Thus the nephrologist has two choices: restrict renoprotective therapy to those shown to be effective in RCT, or expand the use of renoprotective therapies to include those that, although unproven, are plausibly effective and prudent to use. The goal of this work is to provide the documentation needed for the nephrologist to choose between these strategies. METHODS: This work first describes the mechanisms believed to be involved in the progression of renal disease. Based largely on this information, 18 separate interventions that slow the progression are described. Each intervention is assigned a level of recommendation (Level 1 is the highest and Level 3 the lowest) according to the strength of evidence supporting its renoprotective efficacy. RESULTS: The number of interventions at each level of recommendation are: Level 1, N = 4; Level 2, N = 4; Level 3, N = 10. Our own experience with the multiple-risk-factor intervention is that most patients can achieve the majority of the Level 1 and 2 interventions, and many of the Level 3 interventions. We recommend the expanded renoprotection strategy. CONCLUSION: This work advances the hypothesis that, until better information becomes available, a broad-based, multiple-risk-factor intervention intended to slow the progression of renal disease can be justified in those with progressive nephropathies. This work is intended primarily for clinical nephrologists and thus each recommended intervention is described in substantial practical detail.

Disease Progression↗
PubMedDate not supplied

Economic evaluations relating to diabetes: a descriptive review and their compliance with guidance.

From a search of the Health Economics Evaluations Database (HEED), 301 studies relating to diabetes-related interventions were identified. Of these, 223 studies contained some original data, i.e., were applied studies. Over the 1990s, the number of studies undertaken in this area appears to be increasing year on year, and more of the studies are applicable to the USA than to all other countries combined. Most studies are peer reviewed, the main type of analysis is cost-consequence, and the interventions most often assessed are pharmaceutical and care services. Both the public and the private sectors sponsor many of these studies. However, only a fraction of these studies appear to accord with guidance for good economic evaluation. For example, when the search criteria were tightened to capture only those studies that consider both outcomes and costs, 173 studies were identified. Narrowing the search criteria to capture only those studies that were based on randomized controlled trial (RCT) or modeling data-the methods recommended by the US Panel and the National Institute of Clinical Excellence (NICE)-reduced the sample to 56 studies. With specific focus on those studies that evaluated pharmaceuticals, only the modeling approach appeared to show any compliance at all with another key recommendation of the existing guidance on methods; that of using outcome measures that are applicable to a long-term time horizon. Though modeling does offer certain advantages over RCTs (for example, a larger range of comparators can be more readily incorporated, long-term outcome measures can be more easily and inexpensively estimated), modeling results have less internal validity. Also, modeling in itself relies on good RCT data. Therefore, the results of economic evaluations should be interpreted with care, irrespective of whether they are principally based on RCT or model-based methods.

Diabetes Mellitus, Type 2↗