You will be presented with a collection of medical randomized controlled trial (RCT) reports addressing a shared clinical question -- for instance, the efficacy of a medical intervention on a disease or condition. Given the titles and abstracts of these reports, your task is to generate the conclusion of the systematic review article synthesizing the key findings. Your conclusion should be a few sentences long. In your response, include only the conclusion and no other text. The RCT reports are below.



Title 1:
Placebos without Deception: A Randomized Controlled Trial in Irritable Bowel Syndrome
Abstract 1:
Background Placebo treatment can significantly influence subjective symptoms . However , it is widely believed that response to placebo requires concealment or deception . We tested whether open-label placebo ( non-deceptive and non-concealed administration ) is superior to a no-treatment control with matched patient-provider interactions in the treatment of irritable bowel syndrome ( IBS ) . Methods Two-group , r and omized , controlled three week trial ( August 2009-April 2010 ) conducted at a single academic center , involving 80 primarily female ( 70 % ) patients , mean age 47±18 with IBS diagnosed by Rome III criteria and with a score ≥150 on the IBS Symptom Severity Scale ( IBS-SSS ) . Patients were r and omized to either open-label placebo pills presented as “ placebo pills made of an inert substance , like sugar pills , that have been shown in clinical studies to produce significant improvement in IBS symptoms through mind-body self-healing processes ” or no-treatment controls with the same quality of interaction with providers . The primary outcome was IBS Global Improvement Scale ( IBS-GIS ) . Secondary measures were IBS Symptom Severity Scale ( IBS-SSS ) , IBS Adequate Relief ( IBS-AR ) and IBS Quality of Life ( IBS-QoL ) . Findings Open-label placebo produced significantly higher mean ( ±SD ) global improvement scores ( IBS-GIS ) at both 11-day midpoint ( 5.2±1.0 vs. 4.0±1.1 , p<.001 ) and at 21-day endpoint ( 5.0±1.5 vs. 3.9±1.3 , p = .002 ) . Significant results were also observed at both time points for reduced symptom severity ( IBS-SSS , p = .008 and p = .03 ) and adequate relief ( IBS-AR , p = .02 and p = .03 ) ; and a trend favoring open-label placebo was observed for quality of life ( IBS-QoL ) at the 21-day endpoint ( p = .08 ) . Conclusion Placebos administered without deception may be an effective treatment for IBS . Further research is warranted in IBS , and perhaps other conditions , to eluci date whether physicians can benefit patients using placebos consistent with informed consent . Trial Registration Clinical Trials.gov


Title 2:
Behavioral conditioning of immunosuppression is possible in humans.
Abstract 2:
Behavioral conditioned immunosuppression has been described in rodents as the most impressive demonstration of brain-to-immune system interaction . To analyze whether behavioral conditioned immunosuppression is possible in humans , healthy subjects in this double-blind , placebo-controlled study were conditioned in four sessions over 3 consecutive days , receiving the immunosuppressive drug cyclosporin A as an unconditioned stimulus paired with a distinctively flavored drink ( conditioned stimulus ) each 12 h. In the next week , re-exposure to the conditioned stimulus ( drink ) , but now paired with placebo capsules , induced a suppression of immune functions as analyzed by the IL-2 and IFN-gamma mRNA expression , intracellular production , and in vitro release of IL-2 and IFN-gamma , as well as lymphocyte proliferation . These data demonstrate for the first time that immunosuppression can be behaviorally conditioned in humans


Title 3:
[Efficacy of a non blind placebo prescription].
Abstract 3:
The aim of our open clinical trial was to determine the efficacy and the tolerance of a blue coloured placebo in moderated anxious patients ( Hamilton score below 15 ) and a red one for tired patients without DSM IV criteria of major depressive disorder . All the patients knew that treatment was a placebo and so , had no pharmacological effect . The trial run over seven days . All patients were considered as responders if their initial symptoms were reduced more than 50 % . At the end of the week , the final clinical evaluation showed that 18 patients about 34 were in good condition ( 10 anxious patients , 7 women and 3 men , and 8 tired patients , 4 women and 4 men ) . The anxious score of Hamilton scale was reduced of 63 % ; 16 of the 18 responders were absolutely sure that the treatment was usefull . Four patients were obliged to stop their treatment because side effects : insomnia , tiredness and sleepiness , gastric pain and itching of fore arm


Title 4:
Does informed consent influence therapeutic outcome? A clinical trial of the hypnotic activity of placebo in patients admitted to hospital.
Abstract 4:
To examine whether written informed consent might influence the results of clinical trials the effect of placebo when given with or without informed consent to patients suffering from insomnia was studied . The study was a single blind observer blinded trial , and patients were paired according to sex , age , and hospital environment . R and omisation assigned the first patient of each pair to the control group ( without informed consent ) or the group to give informed consent . Of the 56 patients , 26 refused to give informed consent , and the age and sex distribution of these differed significantly ( p less than 0.02 ) from the 30 pairs of patients ultimately enrolled into the study . In this " biased " sample , the hypnotic activity of placebo was significantly higher in the control group ( p less than 0.05 ) . It is concluded that the informed consent procedure biases the results of clinical trials and might affect their general applicability


Title 5:
Open-label placebo treatment in chronic low back pain: a randomized controlled trial
Abstract 5:
Abstract This r and omized controlled trial was performed to investigate whether placebo effects in chronic low back pain could be harnessed ethically by adding open-label placebo ( OLP ) treatment to treatment as usual ( TAU ) for 3 weeks . Pain severity was assessed on three 0- to 10-point Numeric Rating Scales , scoring maximum pain , minimum pain , and usual pain , and a composite , primary outcome , total pain score . Our other primary outcome was back-related dysfunction , assessed on the Rol and –Morris Disability Question naire . In an exploratory follow-up , participants on TAU received placebo pills for 3 additional weeks . We r and omized 97 adults reporting persistent low back pain for more than 3 months ' duration and diagnosed by a board-certified pain specialist . Eighty-three adults completed the trial . Compared to TAU , OLP elicited greater pain reduction on each of the three 0- to 10-point Numeric Rating Scales and on the 0- to 10-point composite pain scale ( P < 0.001 ) , with moderate to large effect sizes . Pain reduction on the composite Numeric Rating Scales was 1.5 ( 95 % confidence interval : 1.0 - 2.0 ) in the OLP group and 0.2 ( −0.3 to 0.8 ) in the TAU group . Open-label placebo treatment also reduced disability compared to TAU ( P < 0.001 ) , with a large effect size . Improvement in disability scores was 2.9 ( 1.7 - 4.0 ) in the OLP group and 0.0 ( −1.1 to 1.2 ) in the TAU group . After being switched to OLP , the TAU group showed significant reductions in both pain ( 1.5 , 0.8 - 2.3 ) and disability ( 3.4 , 2.2 - 4.5 ) . Our findings suggest that OLP pills presented in a positive context may be helpful in chronic low back pain


Title 6:
The effects of a caffeine placebo and suggestion on blood pressure, heart rate, well-being and cognitive performance.
Abstract 6:
We studied the effect of suggestion and different instructions in a balanced placebo design . One hundred and fifty-nine subjects were r and omized into a 2 * 4 factorial design . All subjects except a control group received a caffeine placebo . Subjects were r and omized to a condition which was identical to an earlier study , or received an information about scientifically proven effects of caffeine ( factor 1 ) . The second factor varied instructions : subjects were either made to expect coffee , no coffee or were in a double blind condition and were told either coffee or placebo would be applied . Dependent measures were blood pressure , heart rate , well-being and a cognitive task . There was one main effect of the instruction factor ( P=0.03 ) on diastolic blood pressure , with the group ' told caffeine ' reporting significantly smaller decrease in diastolic blood pressure than controls and subjects in the double blind condition . There were no other main effects on both the instruction or suggestion factor , and no interactions . Contrary to the literature , instruction effects were very small . This was apparently due to the fact that placebo-caffeine in the dose used in this study --one cup of strong ' coffee'--did not produce expectancy effects strong enough to affect the parameters measured . It is concluded that the placebo-caffeine research paradigm is not suitable for research ing instruction effects in Germany , and that reported effects should be reproduced with tighter controls


Title 7:
Effects of expectation and caffeine on arousal, well-being, and reaction time
Abstract 7:
The objective of this study is to determine the impact of expectation associated with placebo and caffeine ingestion . We used a three-armed , r and omized , double-blind design . Two three-armed experiments varying instruction ( true , false , control ) investigated the role of expectations of changes in arousal ( blood pressure , heart rate ) , subjective well-being , and reaction time ( RT ) . In Experiment 1 ( N = 45 ) , decaffeinated coffee was administered , and expectations were produced in one group by making them believe they had ingested caffeinated coffee .  In Experiment 2 ( N = 45 ) , caffeinated orange juice was given in both experimental groups , but only one was informed about the true content . In Experiment 1 , a significant effect for subjective alertness was found in the placebo treatment compared to the control group . However , for RT and well-being no significant effects were found . In Experiment 2 , no significant expectancy effects were found . Caffeine produced large effects for blood pressure in both treatments compared to the control group , but the effects were larger for the false information group . For subjective well-being ( alertness , calmness ) , considerable but nonsignificant changes were found for correctly informed participants , indicating possible additivity of pharmacologic effect and expectations . The results tentatively indicate that placebo and expectancy effects primarily show through introspection


Title 8:
Open-label use of placebos in the treatment of ADHD: a pilot study.
Abstract 8:
BACKGROUND This study examined short-term efficacy , side effects and acceptability of a placebo treatment procedure design ed to maintain children with attention deficit hyperactivity disorder ( ADHD ) on 50 % of their usual stimulant dose . METHODS An open-label prospect i ve crossover trial was conducted in 26 children with ADHD , ages 7 - 15 years , stable on stimulant therapy , followed at a community-based developmental paediatrics ADHD clinic . Subjects were r and omly assigned to one of two orders of experimental conditions : ( 1 ) baseline ( 100 % ) dose ( 1 week ) , then 50 % dose ( 1 week ) , then 50 % dose + placebo ( 1 week ) , or ( 2 ) baseline ( 100 % ) , then 50 % dose + placebo , then 50 % dose . The inert nature of the placebo was fully disclosed to parent and child . Treatment was open-label for child , parents and physician , but single blind for teachers . Main outcome measures included weekly IOWA Conners parent and teacher rating scales , the Pittsburgh side effects rating scale ( PSERS ) and the Clinical Global Impressions ( CGI ) scale . RESULTS Parent IOWA showed ADHD behaviour tended to remain the same when the dose of stimulant medication was reduced with placebo but to deteriorate when the dose was reduced without placebo . There were no significant differences between conditions on the Teacher IOWA . PSERS scores were higher at baseline than on 50 % dose . On the CGI , there was a significant difference ( P = 0.004 ) between the 50 % dose and the 50 % + placebo conditions . Individual subject analysis showed that eight subjects met criteria for responder . CONCLUSIONS Results indicate that the open-label placebo treatment was acceptable and efficacious in the short term for some children
Open-label placebos appear to have positive clinical effects compared to no treatment .