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Results for “Randomized controlled trials”

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PubMed2026

Oblique Lateral Interbody Fusion With Lateral Vertebral Screw Fixation Versus Transforaminal Lumbar Interbody Fusion for Severe Lumbar Stenosis: Results of a Multicenter Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES: The benefits of oblique lateral interbody fusion (OLIF) vs transforaminal lumbar interbody fusion (TLIF) in severe lumbar stenosis (Schizas C/D) remain uncertain. This randomized trial compared clinical, radiographic, and safety outcomes of OLIF and TLIF. METHODS: From November 2018 to December 2021, a prospective, multicenter, randomized controlled trial enrolled 260 adults with single-level severe stenosis and instability. In total, 224 patients were randomized to OLIF or TLIF. Prespecified outcomes followed consolidated standards of reporting trials. Primary outcomes were visual analog scale back/leg pain and Oswestry Disability Index (ODI), with minimal clinically important difference thresholds of ODI ≥12-13 points or ≥30% improvement, and visual analog scale ≥1.5-2.0 points. Radiographic measures included disc height, lumbar and segmental lordosis, and canal cross-sectional area (CSA). Complications were recorded. Ethics approval was obtained from the institutional review board, the trial was registered with ISRCTN.com , and all patients provided written informed consent. RESULTS: In total, 224 patients were randomized, 5 were lost to follow-up (TLIF n = 2, OLIF n = 3). Baseline features were comparable. OLIF was associated with shorter operative time, less blood loss, earlier ambulation, and shorter hospital stay (all P < .05). Both groups achieved significant, clinically meaningful improvements. OLIF showed greater back pain reduction at 3-6 months and 2 years ( P < .05) and superior ODI improvement at 3 and 6 months ( P < .001), although long-term ODI scores were similar. Radiographically, OLIF provided greater restoration of disc height and segmental lordosis (all P < .001) and demonstrated progressive CSA increase (dynamic decompression), whereas TLIF achieved immediate, sustained CSA enlargement. Fusion rates were comparable at 1-2 years. Complication rates were low and similar (7.3% TLIF vs 5.5% OLIF), with most OLIF-specific events transient. CONCLUSION: Both OLIF and TLIF yield improvements in severe lumbar stenosis. OLIF offers perioperative advantages, earlier functional recovery, radiographic restoration, and dynamic canal remodeling, supporting its role as an equivalent alternative for lumbar spinal stenosis with some secondary advantages.

Humans↗

PubMed1994

Incremental increases in oxytocin infusion regimens for induction of labor at term in primigravidas: a randomized controlled trial.

OBJECTIVE: To compare induction of labor by intravenous oxytocin in regimens increasing incrementally at 15- and 30-minute intervals. METHODS: In a randomized controlled trial, 124 primigravidas requiring induction of labor by oxytocin infusion were randomly allocated to incremental increases at 30-minute intervals (62 patients) or 15-minute intervals (62 patients). The main outcomes assessed were mode of delivery, complications of labor and delivery (precipitate labor, hyperstimulation, postpartum hemorrhage, perineal tears, puerperal pyrexia), and number of days in the hospital. RESULTS: The 30-minute incremental regimen resulted in less precipitate labor (odds ratio 0.233, 95% confidence interval [CI] 0.042-0.55, chi 2 = 4.133), less uterine hyperstimulation (odds ratio 0.17, 95% CI 0.015-1.906), and reduced length of stay in the hospital (difference in medians 3 days, 95% CI for difference in medians 2-4 days). The induction-delivery interval was longer with 30 minutes (median 8 hours) than with 15 minutes (median 5 hours) (difference in medians 2 hours, 95% CI for difference in medians 0-3 hours). With the 30-minute interval, there was a reduction in the occurrence of postpartum hemorrhage, perineal tears, and puerperal pyrexia, but these differences did not reach statistical significance. CONCLUSION: For the induction of labor in primigravidas, 30-minute incremental increases in the infusion rate of oxytocin were superior to a 15-minute incremental protocol in reducing the incidence of hyperstimulation and precipitous labor.

Adult↗

PubMed2003

A school-based randomized controlled trial of peer-led sex education in England.

This article discusses the design of an ongoing cluster-randomized trial comparing two forms of school-based sex education in terms of educational process and sexual health outcomes. Twenty-nine schools in southern England have been randomized to either peer-led sex education or to continue with their traditional teacher-led sex education. The primary objective is to determine which form of sex education is more effective in promoting young people's sexual health. The trial includes an unusually detailed evaluation of the process of sex education as well as the outcomes. The sex education programs were delivered in school to pupils ages 13-14 years who are being followed until ages 19-20. Major trial outcomes are unprotected sexual intercourse and regretted intercourse by age 16 and cumulative incidence of abortion by ages 19-20. We discuss the rationale behind various aspects of the design, including ethical issues and practical challenges of conducting a randomized trial in schools, data linkage for key outcomes to reduce bias, and integrating process and outcome measures to improve the interpretation of findings.

Adolescent↗

PubMed2007

Treatment and prevention of depression after surgery for hip fracture in older people: randomized, controlled trials.

OBJECTIVES: To evaluate the effect of a psychiatric intervention in treating depression (treatment study) and the effect of a psychological treatment in preventing depression (prevention study) after hip fracture in older people. DESIGN: Two linked randomized, controlled trials. SETTING: Orthopedic units in Manchester, England. PARTICIPANTS: Two hundred ninety-three older people who had undergone surgery for a fractured hip: 121 in the treatment study and 172 in the prevention study. MEASUREMENTS: The Geriatric Depression Scale and Hospital Anxiety and Depression Scale for mood, functional tests for mobility and pain measures. RESULTS: There was a slight reduction in depressive symptoms in the active arm of the treatment study. In the prevention study, there was no significant difference in incident depression between the psychological intervention and treatment as usual. There were no differences in the functional and pain outcomes. CONCLUSION: The results from these two randomized, controlled trials show that, after hip fracture surgery, no statistically significant benefits can be achieved from a psychiatric intervention in people who are depressed or a psychological intervention to prevent the onset of depression.

Aged, 80 and over↗

PubMed2005

Maintenance therapies in bipolar disorder: focus on randomized controlled trials.

OBJECTIVE: Lithium remains the cornerstone of maintenance therapy for bipolar disorder despite growing use of other agents, including divalproex, lamotrigine, carbamazepine and the atypical antipsychotics. Lithium has the largest body of data to support its continued use as a prophylactic agent; however, most of this data comes from early studies that did not use contemporary analytic methods. Alternatives to lithium are needed because of the relatively high rate of non-response to lithium monotherapy and the drug's frequent side-effects. This article reviews available data with an emphasis on double-blind, placebo-controlled studies that examine the efficacy of lithium and other putative mood stabilizers: carbamazepine, divalproex, lamotrigine and olanzapine. METHOD: The authors reviewed key literature using Medline searches using key words: bipolar disorder, controlled trials, mood stabilizer, lithium, lomotrigine, divalproex, olanzapine, carbamazepine. RESULTS: Lithium remains the gold standard for overall preventative efficacy in bipolar disorder, especially to decrease manic or hypomanic relapse. Of the mood stabilizers that have marked prophylactic antimanic properties, lithium appears to possess the greatest antidepressant effect. Divalproex may also prevent recurrent bipolar mood episodes but the relative lack of controlled maintenance studies makes this less certain. There now exists an extensive and well-designed research database supporting the use of lamotrigine in the acute and prophylactic management of bipolar I disorder. Lamotrigine offers a spectrum of clinical effectiveness that complements lithium, in that it appears to stabilize mood 'from below baseline' by preventing episodes of depression and has been shown to be effective in rapid-cycling bipolar II disorder. Carbamazepine may be a useful alternative to lithium, divalproex and lamotrigine, particularly for patients with a history of mood-incongruent delusions and other comorbidities, but controlled data is more equivocal and it may lose some of its prophylactic effect over time. Emerging data continue to support the growing use of atypical antipsychotics, particularly olanzapine. CONCLUSIONS: Any monotherapy for use as a maintenance therapy of bipolar disorder appears to be inadequate for long-term use in the management of the majority of patients with bipolar disorder. Combination therapy has become the standard of care in the treatment of bipolar disorder and particularly in patients with treatment-refractory variants such as those with rapid-cycling. The emerging consensus is that patients on monotherapy, if followed for sufficiently long periods, will eventually require concomitant treatment to maintain a full remission. There exists a need for controlled trials that use random assignment to parallel arms including combination therapy followed by data analyses that include both relapse rate and survival techniques.

Bipolar Disorder↗

PubMed1990

A randomized controlled trial of a nursery ritual: wearing cover gowns to care for healthy newborns.

The routine wearing of individual cover gowns by nurses and visitors for direct care of healthy newborns was usual practice on the maternity ward of a regional referral center. We conducted a randomized trial in which cover gowns were not provided for care of infants in the experimental group (n = 222), but were maintained for control infants (n = 230). The principal outcome measured was Staphylococcus aureus colonization of the newborn nares or umbilicus on day 3 or day of discharge. Twenty percent (n = 51) of the experimental group (no gown) had a positive culture compared with 21 percent (n = 47) of the controls. Of the infants with positive cultures, two in each group exhibited symptoms of overt S. aureus infection. Experimental infants were similar to controls with respect to feeding method, route of delivery, amount of time spent rooming-in, and average number of visitors per day. In the group of positively cultured infants, the mothers experienced longer labor, and more vaginal examinations in labor, and the number of males undergoing circumcision was higher. We concluded that routine use of cover gowns was unwarranted, and we have altered the ward policy accordingly. This also has had a positive economic effect.

Ceremonial Behavior↗

PubMed2006

Commentary on meta-analysis of randomized controlled trials for HIV treatment adherence interventions. Research directions and implications for practice.

This meta-analysis of randomized controlled trials (RCTs) of interventions for adherence to antiretroviral therapy for HIV indicates that participants who received an adherence intervention were 1.5 times as likely to report 95% adherence and 1.25 times as likely to achieve an undetectable viral load than participants in comparison conditions. The magnitude of the aggregated intervention effect is an encouraging message for HIV treatment providers, but more work is needed. For the next generation of international adherence research, there are multiple challenges that require the collaboration of providers, patients, government funders, donor agencies, and policy-makers. This commentary examines the strengths and limitations of the evidence base, identifies critical research directions, and calls for the development of a formal process to guide the rapid implementation of efficacious adherence interventions into community and clinical practice.

Anti-HIV Agents↗

PubMed2026

Impact of a multimodal prehabilitation program on postoperative cognitive dysfunction: a single-center randomized controlled trial.

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a frequent complication after cardiac surgery. Exercise-based prehabilitation may enhance functional reserve and reduce vulnerability to perioperative cerebral insults. We hypothesized that multimodal prehabilitation reduces POCD 3 months after cardiac surgery. METHODS: This prespecified substudy of a single-center randomized controlled trial (NCT03466606) included patients aged ≥50 years undergoing elective coronary artery bypass grafting and/or valve surgery. Participants were randomized 1:1 to 4-6 weeks of multimodal prehabilitation (exercise training, nutritional support, and psychological support) or standard preoperative care. Cognitive function was assessed at baseline and 3 months postoperatively using an age- and education-adjusted neuropsychological battery. POCD was defined as performance ≥1.5 standard deviations below normative values in at least 2 cognitive tests, excluding the Mini-Mental State Examination. Logistic regression analyses were performed to evaluate factors associated with POCD. RESULTS: Of 160 participants screened from the parent trial, 134 met eligibility criteria for the substudy and were randomized; 116 completed 3-month follow-up (prehabilitation n = 53; control n = 63). POCD occurred in 29 patients (25%), including 15/53 (28%) in the prehabilitation group and 14/63 (22%) in controls (odds ratio [OR] 1.37, 95% confidence interval [CI] 0.54-3.50, P = 0.52). In multivariable analysis, preoperative cognitive impairment was independently associated with POCD (OR 13.28, 95% CI 4.06-43.41, P < 0.001), whereas prehabilitation was not (OR 1.09, 95% CI 0.35-3.45, P = 0.877). Higher physical activity levels at 3 months were associated with lower odds of POCD (OR 0.97, 95% CI 0.95-1.00, P = 0.047). CONCLUSIONS: In this randomized controlled trial, a 4-6-week multimodal prehabilitation program did not reduce postoperative cognitive dysfunction 3 months after cardiac surgery. Although the intervention did not achieve measurable cognitive protection, the observed association between postoperative physical activity levels and postoperative cognitive dysfunction warrants further investigation.

Humans↗

PubMed2004

Developing measures of surgeons' equipoise to assess the feasibility of randomized controlled trials in vascular surgery.

BACKGROUND: Equipoise is defined medically as a state of genuine uncertainty about the relative benefits of alternative treatment options. This study investigated individual and collective equipoise among vascular surgeons for controversial clinical questions to assess the feasibility of conducting randomized controlled trials. METHODS: Vascular surgeons throughout Australia and New Zealand received a survey by mail. RESULTS: Vascular surgeons (n=146, 77% response fraction) were able to quantify the strength of their treatment preferences and did so differentially between clinical scenarios using a simple scale. Almost one quarter (24%; 95% CI, 18%-32%) were completely undecided about whether carotid endarterectomy or carotid stenting was preferable to treat carotid stenosis in high-risk patients, indicating individual equipoise. In contrast, the vast majority of respondents (89%; 95% CI, 82%-93%) favored carotid endarterectomy over carotid stenting for average-risk patients, suggesting lack of community equipoise for this patient group. Similarly, there was lack of community equipoise for treatments for abdominal aortic aneurysm in high-risk patients with 88% (95% CI, 81%-92%) favoring a minimally invasive approach. Older respondents were consistently less willing to take part in randomized trials, with strength of treatment preference also independently predicting willingness to participate in 4 of 6 trials. CONCLUSIONS: Individual and community equipoise can be measured in a representative sample of surgeons as part of the feasibility assessment for future randomized controlled trials.

Adult↗

PubMed2006

A literature review of randomized controlled trials of the organization of care at the end of life.

We searched nine electronic databases for randomized controlled trials (RCTs) about care at the end of life and found 23 RCTs. We assessed their quality using the criteria of the Cochrane Collaboration. The RCTs researched three themes: (a) the effect of providing palliative care through dedicated community teams on quality of life, on the management of symptoms, on satisfaction with care, on the duration of the palliative period, and on place of death; (b) the effects of specific palliative care interventions-advanced planning of care for the end of life, patient-held records, providing quality-of-life data to patients and physicians, grief education for relatives, palliative care education for nurses, and palliative care for patients with dementia; and (c) the costs of palliative compared to conventional care. We identify difficulties in conducting research on palliative care and solutions and discuss future possible research themes.

Community Health Services↗

PubMed1992

Functional outcomes of low back pain: comparison of four treatment groups in a randomized controlled trial.

The revised Oswestry Low Back Pain Questionnaire (ROLBPQ) and Roland-Morris Activity Scale (RMAS) were compared in a randomized controlled trial of chiropractic manipulation, stroking massage, corset and transcutaneous muscular stimulation (TMS). This trial employed specific inclusion and exclusion criteria, including nonspecific low back pain for a duration of 3 wk to 6 months and ages between 18 and 55. We had the opportunity to ask 85 patients to answer the questionnaires. Sixty-three patients, who completed the initial and final evaluations, were used for data analysis. Both ROLBPQ and RMAS showed good internal consistency with alpha coefficients ranging from .77 to .93. Both instruments showed a significant difference between the chiropractic manipulation and massage groups (p less than .05). RMAS was able to further show significant differences between the chiropractic manipulation and TMS groups, and between the corset and massage groups, but the ROLBPQ failed to do so. RMAS also showed that chiropractic manipulation had a better but nonsignificant result than corset, possibly due to insufficient sample size and/or duration of treatment. We conclude that both instruments are reliable for measuring low back pain disability, and chiropractic manipulation has a superior short-term benefit when compared to stroking massage and TMS in subacute low back pain patients. In addition, it appears that RMAS is preferable in a clinical trial situation for subacute low back pain because it is more sensitive than ROLBPQ to detect changes.

Adolescent↗

PubMed2004

The effect of oral iron admiinistration on mycophenolate mofetil absorption in renal transplant recipients: a randomized, controlled trial.

BACKGROUND: Oral iron supplements are frequently prescribed to renal transplant recipients in the early posttransplant period. A recent trial in seven healthy volunteers demonstrated a significant 91% reduction in mycophenolate mofetil (MMF) absorption when coadministered with oral iron. However, the effect of iron on MMF absorption in renal transplant patients has not been studied. METHODS: An open-label, randomized, controlled trial was undertaken in which new renal transplant recipients were randomly allocated to receive iron supplements with a morning dose of MMF, iron supplements given 4 hr after MMF at midday, or no iron supplements. Blood samples were taken for estimation of mycophenolic acid (MPA) area under the curve (AUC) at day 5 posttransplant. The primary endpoint was the day 5 MPA AUC, with secondary endpoints including acute rejection and MMF toxicity in the first 4 weeks posttransplant. Prospective power calculations indicated that a minimum of 13 patients in each group would be required to have a 90% probability of detecting a clinically significant reduction (10 mg/hr/L) in MPA AUC for iron-treated patients. RESULTS: Forty patients completed the study. There were no differences in baseline demographic data between the groups. The mean+/-standard deviation MPA AUC measurements for the groups receiving no iron (n=13), iron and MMF together (n=14), and iron and MMF spaced apart (n=13) were 34.5+/-8.7, 33.7+/-11.4, and 32.1+/-8.1 microg/hr/mL, respectively (P=0.82). Rates of acute rejection, cytopenia, infection, and gastrointestinal intolerance were comparable between the groups. CONCLUSIONS: There is no significant effect of oral iron supplements on MMF absorption as determined by measured blood concentrations. The practice of routinely giving oral iron in such patients seems safe from an immunosuppression drug-interaction standpoint.

Adult↗

PubMed2000

Active management of labor: a cost analysis of a randomized controlled trial.

OBJECTIVE: To compare the costs of a protocol of active management of labor with those of traditional labor management. DESIGN: Cost analysis of a randomized controlled trial. METHODS: From August 1992 to April 1996, we randomly allocated 405 women whose infants were delivered at the University of New Mexico Health Sciences Center, Albuquerque, to an active management of labor protocol that had substantially reduced the duration of labor or a control protocol. We calculated the average cost for each delivery, using both actual costs and charges. RESULTS: The average cost for women assigned to the active management protocol was $2,480.79 compared with an average cost of $2,528.61 for women in the control group (P = 0.55). For women whose infant was delivered by cesarean section, the average cost was $4,771.54 for active management of labor and $4,468.89 for the control protocol (P = 0.16). Spontaneous vaginal deliveries cost an average of $27.00 more for actively managed patients compared with the cost for the control protocol. CONCLUSIONS: The reduced duration of labor by active management did not translate into significant cost savings. Overall, an average cost saving of only $47.91, or 2%, was achieved for labors that were actively managed. This reduction in cost was due to a decrease in the rate of cesarean sections in women whose labor was actively managed and not to a decreased duration of labor.

Costs and Cost Analysis↗

PubMed1995

Laparoscopic versus open inguinal herniorrhaphy: preliminary results of a randomized controlled trial.

BACKGROUND: Benefits of laparoscopic herniorrhaphy (LH) over open hernia repair (OH) remain unproved. METHODS: Interim analysis of a prospective randomized controlled trial compared OH with LH where study outcomes were measured by third-party evaluators through patient interviews. RESULTS: Both groups were well matched for all baseline parameters, although LH patients anticipated a quicker postoperative recovery than OH (p = 0.014). No significant difference was noted in operating time or surgeon operative satisfaction. The median duration of hospital stay was 1 day in both groups; LH patients made use of significantly less postoperative narcotics than OH (p = 0.02). No difference was observed in the durations of convalescence (LH, 9.6 +/- 7.6 days; OH, 10.9 +/- 7.4 days). Greater improvements in quality of life were exhibited in LH patients than OH patients 1 month after operation (p = 0.035), with one of the two measures used. A greater percentage of LH patients seemed "very satisfied with their operation" (p = 0.07). Complication rates were similar, and a single recurrence, in a patient in the OH group, has been observed after a median follow-up of 14 months. CONCLUSIONS: Direct cost measurements showed LH to be 40% more expensive than OH in the context of a Canadian-type health care system. To date, benefits in postoperative pain and possibly quality of life have been detected in the LH group.

Adult↗

PubMed2005

A randomized, controlled trial of the effectiveness of community-based case management in insuring uninsured Latino children.

BACKGROUND: Lack of health insurance adversely affects children's health. Eight million US children are uninsured, with Latinos being the racial/ethnic group at greatest risk for being uninsured. A randomized, controlled trial comparing the effectiveness of various public insurance strategies for insuring uninsured children has never been conducted. OBJECTIVE: To evaluate whether case managers are more effective than traditional methods in insuring uninsured Latino children. DESIGN: Randomized, controlled trial conducted from May 2002 to August 2004. SETTING AND PARTICIPANTS: A total of 275 uninsured Latino children and their parents were recruited from urban community sites in Boston. INTERVENTION: Uninsured children were assigned randomly to an intervention group with trained case managers or a control group that received traditional Medicaid and State Children's Health Insurance Program (SCHIP) outreach and enrollment. Case managers provided information on program eligibility, helped families complete insurance applications, acted as a family liaison with Medicaid/SCHIP, and assisted in maintaining coverage. MAIN OUTCOME MEASURES: Obtaining health insurance, coverage continuity, the time to obtain coverage, and parental satisfaction with the process of obtaining insurance for children were assessed. Subjects were contacted monthly for 1 year to monitor outcomes by a researcher blinded with respect to group assignment. RESULTS: One hundred thirty-nine subjects were assigned randomly to the intervention group and 136 to the control group. Intervention group children were significantly more likely to obtain health insurance (96% vs 57%) and had approximately 8 times the adjusted odds (odds ratio: 7.78; 95% confidence interval: 5.20-11.64) of obtaining insurance. Seventy-eight percent of intervention group children were insured continuously, compared with 30% of control group children. Intervention group children obtained insurance significantly faster (mean: 87.5 vs 134.8 days), and their parents were significantly more satisfied with the process of obtaining insurance. CONCLUSIONS: Community-based case managers are more effective than traditional Medicaid/SCHIP outreach and enrollment in insuring uninsured Latino children. Case management may be a useful mechanism to reduce the number of uninsured children, especially among high-risk populations.

Boston↗

PubMed1982

Randomized controlled trial of colestipol in antibiotic-associated colitis.

Thirty-eight patients with severe antibiotic-associated postoperative diarrhoea were entered into a randomized controlled trial to compare colestipol (an ion exchange resin) in 17 patients with placebo (sherbet) in 21 patients. Clostridium difficile or its toxin was present before treatment in 12 of the colestipol group, compared with only 5 in the placebo group. Because of the low incidence of Cl. difficile or its toxin, the placebo group data from 22 patients receiving placebo in a previous trial (9 of whom had Cl. difficile or toxin) were included for comparison. Neither colestipol nor placebo had any influence on the faecal excretion of Cl. difficile or its toxin. Colestipol was clinically no better than placebo. In view of the persistent faecal excretion of Cl. difficile toxin, ion exchange resins cannot be recommended for the treatment of antibiotic-associated colitis.

Anti-Bacterial Agents↗

PubMed2006

Oxycodone for cancer-related pain: meta-analysis of randomized controlled trials.

To evaluate the efficacy and tolerability of oxycodone in cancer-related pain, we conducted a systematic review of randomized controlled trials. Four studies, comparing oral oxycodone with either oral morphine (n = 3) or oral hydromorphone (n = 1), were suitable for meta-analysis. Standardized mean differences in pain scores comparing oxycodone with control groups were pooled using random-effects models. Overall, there was no evidence that mean pain scores differed between oxycodone and control drugs (pooled standardized mean difference, 0.04; 95% confidence interval [CI], -0.29 to 0.36; P = .8; I(2) = 62%). In meta-regression analyses, pain scores were higher for oxycodone compared with morphine (0.20; 95% CI, -0.04 to 0.44) and lower compared with hydromorphone (-0.36; 95% CI, -0.71 to 0.00), although these effect sizes were small. The efficacy and tolerability of oxycodone are similar to morphine, supporting its use as an opioid for cancer-related pain.

Analgesics, Opioid↗

PubMed2002

In randomized controlled trials, should subjects in both placebo and drug groups be expected to guess that they are taking drug 50% of the time?

Part of the design of some randomized controlled trials has included asking patients to guess whether they are taking placebo or active drug. Some authors have stated that in randomized, double-blind placebo-controlled clinical trials patients in each group should guess that they are taking placebo half the time. However, this pattern should occur only under a limited set of circumstances. This paper explores the factors that affect the guess and the role of the guess in understanding both the establishment and the maintenance of the blind. It suggests that more than half of those in the treatment group should guess they are taking active drug if treatment or side-effects are powerful. Though the randomized controlled trial has become the paradigmatic tool to assess treatment efficacy, studies are still needed to validate key assumptions make by investigators and the effect of violation of these assumptions on study outcomes.

Cues↗