***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Summary Nonspecific placebo factors such as patients ' perceptions of a treatment and expectations toward effect seem to be central to the clinical efficacy of acupuncture analgesia . ABSTRACT It is well known that acupuncture has pain‐relieving effects , but the contribution of specific and especially nonspecific factors to acupuncture analgesia is less clear . One hundred one patients who developed pain of ≥3 on a visual analog scale ( VAS , 0 to 10 ) after third molar surgery were r and omized to receive active acupuncture , placebo acupuncture , or no treatment for 30 min with acupuncture needles with potential for double‐blinding . Patients ' perception of the treatment ( active or placebo ) and expected pain levels ( VAS ) were assessed before and halfway through the treatment . Looking at actual treatment allocation , there was no specific effect of active acupuncture ( P = .240 ) , but there was a large and significant nonspecific effect of placebo acupuncture ( P < .001 ) , which increased over time . Interestingly , however , looking at perceived treatment allocation , there was a significant effect of acupuncture ( P < .001 ) , indicating that patients who believed they received active acupuncture had significantly lower pain levels than those who believed they received placebo acupuncture . Expected pain levels accounted for significant and progressively larger amounts of the variance in pain ratings after both active and placebo acupuncture ( up to 69.8 % ) . This is the first study to show that under optimized blinding conditions , nonspecific factors such as patients ' perception of and expectations toward treatment are central to the efficacy of acupuncture analgesia and that these factors may contribute to self‐reinforcing effects in acupuncture treatment . To obtain an effect of acupuncture in clinical practice , it may therefore be important to incorporate and optimize these factors Summary This multifactorial mixed‐ methods r and omized controlled trial quantified the specific and nonspecific factors of acupuncture , and found that the practitioner , not the treatment , has the strongest effect on outcome . Abstract The nonspecific effects of acupuncture are well documented ; we wished to quantify these factors in osteoarthritic ( OA ) pain , examining needling , the consultation , and the practitioner . In a prospect i ve r and omised , single‐blind , placebo‐controlled , multifactorial , mixed‐ methods trial , 221 patients with OA awaiting joint replacement surgery were recruited . Interventions were acupuncture , Streitberger placebo acupuncture , and mock electrical stimulation , each with empathic or nonempathic consultations . Interventions involved eight 30‐minute treatments over 4 weeks . The primary outcome was pain ( VAS ) at 1 week posttreatment . Face‐to‐face qualitative interviews were conducted ( purposive sample , 27 participants ) . Improvements occurred from baseline for all interventions with no significant differences between real and placebo acupuncture ( mean difference −2.7 mm , 95 % confidence intervals −9.0 to 3.6 ; P = .40 ) or mock stimulation ( −3.9 , −10.4 to 2.7 ; P = .25 ) . Empathic consultations did not affect pain ( 3.0 mm , −2.2 to 8.2 ; P = .26 ) but practitioner 3 achieved greater analgesia than practitioner 2 ( 10.9 , 3.9 to 18.0 ; P = .002 ) . Qualitative analysis indicated that patients ’ beliefs about treatment veracity and confidence in outcomes were reciprocally linked . The supportive nature of the trial attenuated differences between the different consultation styles . Improvements occurred from baseline , but acupuncture has no specific efficacy over either placebo . The individual practitioner and the patient ’s belief had a significant effect on outcome . The 2 placebos  were equally as effective and credible as acupuncture . Needle and nonneedle placebos are equivalent . An unknown characteristic of the treating practitioner predicts outcome , as does the patient ’s belief ( independently ) . Beliefs about treatment veracity shape how patients self‐report outcome , complicating and confounding study interpretation The purpose of this study was to investigate the comparative effectiveness of early use of thrust ( TM ) and non-thrust manipulation ( NTM ) in sample of patients with mechanical low back pain ( LBP ) . The r and omized controlled trial included patients with mechanically reproducible LBP , ≥ age 18-years who were r and omized into two treatment groups . The main outcome measures were the Oswestry Disability Index ( ODI ) and a Numeric Pain Rating Scale ( NPRS ) , with secondary measures of Rate of Recovery , total visits and days in care , and the work subscale of the Fears Avoidance Beliefs Question naire work subscale ( FABQ-w ) . A two-way mixed model MANCOVA was used to compare ODI and pain , at baseline , after visit 2 , and at discharge and total visits , days in care , and rate of recovery ( while controlling for patient expectations and clinical equipoise ) . A total of 149 subjects completed the trial and received care over an average of 35 days . There were no significant differences between TM and NTM at the second visit follow-up or at discharge with any of the outcomes categories . Personal equipoise was significantly associated with ODI and pain . The findings suggest that there is no difference between early use of TM or NTM , and secondarily , that personal equipoise affects study outcome . Within-groups changes were significant for both groups Objectives To develop a sham needle device and test its credibility as a control for acupuncture when used in a r and omised controlled trial of myofascial trigger point needling in patients with whiplash associated pain . Methods Sham needles were developed by blunting true acupuncture needles . Whiplash injured patients ( < 16 weeks duration ) were r and omly allocated to receive either true acupuncture or the “ placebo ” sham needle control . The true and sham needling interventions were delivered using the same st and ardised procedure . Patients were informed that they would receive either real or placebo needles , and asked ( i ) to state which treatment they believed they had received ( treatment belief ) ; ( ii ) to complete the four item Borkovec and Nau self- assessment credibility scale . Results were compared between groups and the analysis explored whether a patient 's previous experience of acupuncture was related to their treatment belief . Other outcomes of the study will be reported elsewhere . Results 20 patients received the true acupuncture and 21 received the sham . There was no significant difference between the treatment beliefs of the two groups ( χ 2 = 1.51 ; p>0.2 ) nor in the mean item scores on the Borkovec and Nau credibility scale ( t test , p values ranged from 0.38 to 0.87 ) . Of the patients in the sham acupuncture group who had previous experience of acupuncture , none recorded receiving the sham intervention . Conclusion Within the context of this pilot study , the sham acupuncture intervention was found to be a credible control for acupuncture . This supports its use in a planned , definitive , r and omised controlled trial on a similar whiplash injured population Background Placebo needles that can mask acupuncture practitioners to the type of needle used have been considered almost impossible to develop until now . Methods We design ed a double-blind non-penetrating placebo needle , the needle tip of which simply presses against the skin , and a matched penetrating needle . The needles are encased inside an opaque guide tube and the appearance and feel of the pair are design ed to be indistinguishable . To vali date the masking effect for the practitioner , 10 acupuncturists each applied 23 non-penetrating needles and 17 penetrating needles to the Large Intestine-4 point . After removing each needle , they judged whether the needle was ' penetrating ' , ' non-penetrating ' or ' unidentifiable ' . For the validation of patient masking , an acupuncturist r and omly applied a non-penetrating/penetrating needle pair to the bilateral Sanjiao-5 points in 60 volunteers . When both applications were completed , we asked them to write down anything that they noticed regarding the needle application and associated sensations . Results The mean ± SD of correct/unidentifiable/incorrect answers given by the 10 acupuncturists were 17.0 ± 4.1/6.4 ± 3.6/16.6 ± 3.0 , respectively . Regarding patient masking , none of the subjects commented in the question naire that they had received a non-penetrating needle . Of 60 penetrating and 60 non-penetrating needle applications , 48 ( 80.0 % ) and 25 ( 41.7 % ) applications elicited skin penetration sensation and 48 ( 80.0 % ) and 20 ( 33.3 % ) applications elicited de qi , respectively . Conclusion These needles have the potential to mask both practitioners and patients from the type of needle used in acupuncture research Blinding protects against bias but the success of blinding is seldom assessed and reported in clinical trials including studies of acupuncture where blinding represents a major challenge . Recently , needles with the potential for double-blinding were developed , so we tested if acupuncture can be double-blinded in a r and omized study of sixty-seven patients with acute pain ≥ 3 ( 0 - 10 scale following third molar removal ) who received active acupuncture with a penetrating needle or placebo acupuncture with a non-penetrating needle .  To test if acupuncture was administered double-blind , patients and acupuncturists were asked about perceived treatment allocation at the end of the study . To test if there were clues which led to identification of the treatment , deep dull pain associated with needle application and rotation ( termed “ de qi ” in East Asian medicine ) , and patients ’ pain levels were assessed . Perceived treatment allocation depended on actual group allocation ( p < 0.015 ) for both patients and acupuncturists , indicating that the needles were not successful in double-blinding . Up to 68 % of patients and 83 % of acupuncturists correctly identified the treatment , but for patients the distribution was not far from 50/50 . Also , there was a significant interaction between actual or perceived treatment and the experience of de qi ( p = 0.027 ) , suggesting that the experience of de qi and possible non-verbal clues contributed to correct identification of the treatment . Yet , of the patients who perceived the treatment as active or placebo , 50 % and 23 % , respectively , reported de qi . Patients ’ acute pain levels did not influence the perceived treatment . In conclusion , acupuncture treatment was not fully double-blinded which is similar to observations in pharmacological studies . Still , the non-penetrating needle is the only needle that allows some degree of practitioner blinding . The study raises questions about alternatives to double-blind r and omized clinical trials in the assessment of acupuncture treatment Clinicians cl aim that myofascial trigger points ( MTrPs ) are a primary cause of pain in whiplash injured patients . Pain from MTrPs is often treated by needling , with or without injection . We conducted a placebo controlled study to test the feasibility of a phase III r and omised controlled trial investigating the efficacy of MTrP needling in patients with whiplash associated pain . Forty-one patients referred for physiotherapy with a recent whiplash injury , were recruited . Patients were r and omised to receive st and ardised physiotherapy plus either acupuncture or a sham needle control . A trial was judged feasible if : i ) the majority of eligible patients were willing to participate ; ii ) the majority of patients had MTrPs ; iii ) at least 75 % of patients provided completed self- assessment data ; iv ) no serious adverse events were reported and v ) the end of treatment attrition rate was less than 20 % . 70 % of those patients eligible to participate volunteered to do so ; all participants had clinical ly identified MTrPs ; a 100 % completion rate was achieved for recorded self- assessment data ; no serious adverse events were reported as a result of either intervention ; and the end of treatment attrition rate was 17 % . A phase III study is both feasible and clinical ly relevant . This study is currently being planned Background Plantar heel pain can be managed with dry needling of myofascial trigger points ; however , there is only poor- quality evidence supporting its use . Objective The purpose of this study was to evaluate the effectiveness of dry needling for plantar heel pain . Design The study was a parallel-group , participant-blinded , r and omized controlled trial . Setting The study was conducted in a university health sciences clinic . Patients Study participants were 84 patients with plantar heel pain of at least 1 month 's duration . Intervention Participants were r and omly assigned to receive real or sham trigger point dry needling . The intervention consisted of 1 treatment per week for 6 weeks . Participants were followed for 12 weeks . Measurements Primary outcome measures included first-step pain , as measured with a visual analog scale ( VAS ) , and foot pain , as measured with the pain subscale of the Foot Health Status Question naire ( FHSQ ) . The primary end point for predicting the effectiveness of dry needling for plantar heel pain was 6 weeks . Results At the primary end point , significant effects favored real dry needling over sham dry needling for pain ( adjusted mean difference : VAS first-step pain=−14.4 mm , 95 % confidence interval [ 95 % CI]=−23.5 to −5.2 ; FHSQ foot pain=10.0 points , 95 % CI=1.0 to 19.1 ) , although the between-group difference was lower than the minimal important difference . The number needed to treat at 6 weeks was 4 ( 95 % CI=2 to 12 ) . The frequency of minor transitory adverse events was significantly greater in the real dry needling group ( 70 real dry needling appointments [ 32 % ] compared with only 1 sham dry needling appointment [ < 1 % ] ) 
    Output:
    
There was no evidence of a moderating effect of blinding index on pain .
For short-term and long-term pain assessment s pooled effects for inadequately blinded trials were statistically significant in favour of active dry needling , whereas there was no evidence of a difference between active and sham groups for adequately blinded trials .
However , with the caveats of small sample size , generally unclear risk of bias , statistical heterogeneity , potential publication bias , and the limitations of subgroup analyses , the available evidence suggests that inadequate blinding procedures could lead to exaggerated intervention effects in dry needling trials