scholarly journals Placebo control group in COVID-19 vaccine trials: context and timing matters

Author(s):  
Rafael Dal-Ré
Nephrology ◽  
2000 ◽  
Vol 5 (3) ◽  
pp. A97-A97
Author(s):  
Hoy We ◽  
Baker P ◽  
Wang Z ◽  
Cass A ◽  
Mathews Jd ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Li Zhang ◽  
Zhongju Xu ◽  
Tao Jiang ◽  
Jialu Zhang ◽  
Pinxian Huang ◽  
...  

Equus asinus L [Equidae; Asini Corii Colla] (donkey-hide gelatin, Ejiao), a well-known traditional Chinese medicine, has been widely used to nourish the blood, especially for women. The aim of this study was to assess the efficacy and safety of Ejiao in blood-deficient patients. A total of 210 participants were recruited and randomly allocated into the placebo control group and Ejiao-treated group (6 g/day). The primary outcomes on the efficacy of Ejiao included traditional Chinese medicine symptom scores, blood indicators, and SF-36. The secondary outcomes were changes in fireness and safety evaluation. Results showed that Ejiao treatment for 8 weeks had significantly improved dizziness symptoms. Among the tested 24 blood biochemical parameters, the hematocrit and red blood cell numbers decreased in the placebo control group, but decreased significantly less in the Ejiao treatment group. The white blood cell and neutrophil counts increased in the Ejiao group but were within the normal range. In addition, the quality of life improved as the scores in SF-36 domains were significantly higher in the Ejiao group. At the same time, there was no significant change in the fire–heat symptoms score or other safety parameters. Considering all these, our study showed that Ejiao has a promising effect in women suffering from blood deficiency without obvious adverse effects.


1981 ◽  
Author(s):  
G Arapakis ◽  
A Trovas ◽  
G Orphanoudakis ◽  
P Vassilikos

Though the antithrombotic properties of sulfinpyrazone (SP) in arterial thrombosis have been documented, its value in phlebothrombosis remains uncertain. In this randomized double-blind trial, the effect of SP (500mg I.M. twice daily for the first 10 postoperative days) on postoperative DVT was compared with a placebo control group. 96 (65 male and 31 female) patients 41 to 83 years of age undergoing major surgical operations were included in the trial. The composition of the two groups (treated and placebo) were homogenious regarding age, sex and type of operation (0,30<p<0,50). The incidence of DVT was estimated clinically and isotopically by the 125I-labelled figrinogen test.No clinical phlebothrombosis was observed in either group but DVT was detected isotopically in 4 (8,3%) out of 48 in the placebo and in 7 (14,5%) of the 48 in the SP group. Analysis by the x2 showed no statistical significance in the prevalence of postoperative DVT between the two groups (x2<x20,30/1). These results suggest that SP has no place in the prevention of postoperative DVT.


BMJ Open ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. e032469 ◽  
Author(s):  
Vania Sandoz ◽  
Camille Deforges ◽  
Suzannah Stuijfzand ◽  
Manuella Epiney ◽  
Yvan Vial ◽  
...  

IntroductionEmergency caesarean section (ECS) qualifies as a psychological trauma, which may result in postnatal post-traumatic stress disorder (PTSD). Maternal PTSD may not only have a significant negative impact on mother–infant interactions, but also on long-term infant development. The partner’s mental health may also affect infant development. Evidence-based early interventions to prevent the development of postpartum PTSD in mothers are lacking. Immediately after a traumatic event, memory formation is vulnerable to interference. There is accumulating evidence that a brief behavioural intervention including a visuospatial task may result in a reduction in intrusive memories of the trauma.Methods and analysisThis study protocol describes a double-blind multicentre randomised controlled phase III trial testing an early brief maternal intervention including the computer game ‘Tetris’ on intrusive memories of the ECS trauma (≤1 week) and PTSD symptoms (6 weeks, primary outcome) of 144 women following an ECS. The intervention group will carry out a brief behavioural procedure including playing Tetris. The attention-placebo control group will complete a brief written activity log. Both simple cognitive tasks will be completed within the first 6 hours following traumatic childbirth. The intervention is delivered by midwives/nurses in the maternity unit.The primary outcome will be differences in the presence and severity of maternal PTSD symptoms between the intervention and the attention-placebo control group at 6 weeks post partum. Secondary outcomes will be physiological stress and psychological vulnerability, mother–infant interaction and infant developmental outcomes. Other outcomes will be psychological vulnerability and physiological regulation of the partner and their bonding with the infant, as well as the number of intrusive memories of the event.Ethics and disseminationEthical approval was granted by the Human Research Ethics Committee of the Canton de Vaud (study number 2017–02142). Dissemination of results will occur via national and international conferences, in peer-reviewed journals, public conferences and social media.Trial registration numberNCT 03576586.


2007 ◽  
Vol 18 (7) ◽  
pp. 649-655 ◽  
Author(s):  
Peter R. Giancola ◽  
Michelle D. Corman

This article presents the first systematic test of the attention-allocation model for alcohol-related aggression. According to this model, alcohol has a “myopic” effect on attentional capacity that presumably facilitates aggression by focusing attention on more salient provocative, rather than less salient inhibitory, cues in hostile situations. Aggression was assessed using a laboratory task in which mild electric shocks were received from, and administered to, a fictitious opponent. Study 1 demonstrated that a moderate-load cognitive distractor suppressed aggression in intoxicated subjects (to levels even lower than those exhibited by a placebo control group). Study 2 assessed how varying the magnitude of a distracting cognitive load affected aggression in the alcohol and placebo conditions. Results indicated that the moderate-load distraction used in Study 1 (i.e., holding four elements in sequential order in working memory) suppressed aggression best. Cognitive loads of larger and smaller magnitudes were not successful in attenuating aggression.


1995 ◽  
Vol 3 (2) ◽  
pp. 135-145 ◽  
Author(s):  
Jamie L. Moul ◽  
Bert Goldman ◽  
Beverly Warren

The effect of exercise on cognitive performance in an older population was studied. Thirty sedentary men and women 65–72 years of age were randomly assigned to a walking group, a weight training group, or a placebo control group. Intervention groups exercised 30–60 min 5 days per week for 16 weeks, with the walking group training at 60% heart rate reserve, the weight training group employing the DAPRE method of weight progression, and the placebo control group engaging in mild range-of-motion and flexibility movements that kept their heart rates close to resting levels. At baseline and 16 weeks posttraining each subject completed the Ross Information Processing Assessment (RIPA), a maximal graded treadmill test, and a strength assessment of the knee extensors and elbow flexors. Sixteen weeks of walking improved VO2peak of the sedentary subjects 15.8%; VO2peak did not improve in the other two groups. Additionally, the RIPA scores of the walking group increased 7.5%, while those of the weight-training and control groups showed little change.


1999 ◽  
Vol 1 (4) ◽  
pp. 34-49 ◽  
Author(s):  
Richard Niederman ◽  
Maggie C. Tantraphol ◽  
Patricia Slnin ◽  
Catherine Hayes ◽  
Suzy Conway

Abstract Introduction Common clinical experience suggests that tooth whitening agents are 100% effective. This study uses meta-analysis of data from published randomized controlled clinical trials to determine the efficacy of tooth whitening agents. Methods A MEDLINE search strategy was developed and implemented to systematically identify clinical trials on dentist-prescribed, home-applied tooth whitening agents, using 10% carbamide peroxide, published between 1989-1999. Inclusion criteria (e.g., in English, human clinical trials) and exclusion criteria (e.g., not placebo controlled) were established and clinical trials that met these criteria were critically appraised for validity and clinical applicability. Meta-analysis was then used to quantitatively integrate the findings. Results Seven studies were identified that met the inclusion and validity criteria. These studies indicated that: Whitening results in a significant mean change of 6 4 shade guide units (p < 0.01), while the placebo control group exhibited little change (0.7 0.6, p > 0.05). 93% of the bleached patients exhibited 2 shade guide unit change, while 20% of the placebo control group exhibited this change. The brand of bleaching agent had a significant effect on tooth whitening, but the daily application time and duration of treatment did not. Whitening is maintained for 6 months for 1/2 of the people treated. Neither gingival indices nor plaque indices were adversely or favorably affected by bleaching. Clinical Applicability The data from the reviewed studies indicate that rather than being 100% effective, on average: 73% (93% for bleached group minus 20% placebo group) of people who whiten their teeth will exhibit a whitening that is 2 shade guide units greater than the placebo. 20% of the people who use dentist-prescribed, home-applied bleaching will achieve a mean whitening effect of 5 shade guide units. Re-treatment for 50% of people may be necessary to maintain this effect longer than 6 months. The methods used here are Internet applicable for other clinical topics.


PEDIATRICS ◽  
1993 ◽  
Vol 91 (3) ◽  
pp. 624-627
Author(s):  
Mary C. Theroux ◽  
David W. West ◽  
David H. Corddry ◽  
Patrice M. Hyde ◽  
Steven J. Bachrach ◽  
...  

Sedating children safely and effectively for minor laceration repair is a well-recognized clinical problem. A randomized, double-blind, and controlled study was conducted to evaluate the efficacy of intranasal midazolam for reducing stress during the suturing of lacerations in preschool children. Fifty-nine children with simple lacerations that required suturing were randomly assigned to one of three groups. Group 1 received intranasal midazolam, 0.4 mg/kg, prior to suturing. Group 2 received an equivalent volume of normal saline intranasally prior to suturing as a placebo. Group 3 was the control group and received no intervention prior to suturing. Heart rate, respiratory rate, blood pressure, and pulse oximetry were monitored at 5-minute intervals throughout the procedure. Subjective variables were also measured at 5-minute intervals and included a cry score, a motion score, and a struggle score. Parent satisfaction was measured via a short telephone interview the following day. There were no significant differences in outcome between the placebo group and the control group. Their results were pooled and compared with the results for the midazolam group. The midazolam group showed significant reductions for mean heart rate, maximum heart rate, and maximum systolic blood pressure when compared with the placebo/control group. Scores for two of the three subjective variables, cry and struggle, were significantly reduced for the midazolam group. The papoose board was considered unnecessary in retrospect for more than half of patients in the midazolam group compared with only one fifth of patients in the placebo/control group. Telephone follow-up revealed that parents in the midazolam group were twice as likely (68% vs 33%) to find the suture experience in the emergency department better than they had expected. No respiratory depression or any other significant adverse effects were noted in any of the three groups. It is concluded that infranasal midazolam was effective and safe in reducing anxiety and stress, which commonly accompany the suturing of lacerations in healthy preschool children.


PEDIATRICS ◽  
1994 ◽  
Vol 93 (5) ◽  
pp. 871-871
Author(s):  
Mary C. Theroux ◽  
David West

We thank Drs Lopez and Urbansky for their comments. Their observation that the placebo group may have sufficiently biased the combined placebo/control group to account for the significant findings noted is reasonable, despite no significant differences being found between the placebo group and the control group. Analysis of variance among the three groups was carried out for the objective outcome variables. Differences in mean heart rate changes and maximum heart rate changes remained significant, and differences between study versus control groups and study versus placebo groups were both found to be significant, accounting for multiple comparisons.


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