The effects of placebos and nocebos on physical performance

Not "that kind" of doctor: an exploratory study on Doctor of Physical Therapy-patient introductions in the United States

OBJECTIVE

This exploratory study examined the prevalence and determinants of the use of the title 'doctor' among the United States (U.S.) licensed Doctors of Physical Therapy (DPTs) during patient-provider introductions.

METHODS

A cross-sectional analysis of DPTs across eight states was conducted. Binary logistic regression analyzed demographic and experience-related factors influencing title use, including years of experience, board certification status, and clinical instructor (CI) experience. Stepwise logistic regression with forward selection identified significant predictors. Beliefs influencing title use were evaluated through descriptive statistics from multiple choice questions with an option for open-ended responses for additional opinions.

RESULTS

Of the 1,311 participants who met the inclusion criteria, 19.9% reported using 'doctor' during patient-provider introductions. The odds of using the title increased with age and was higher among males, with age controlled for. Completion of a residency program and not being a CI were also associated with greater odds of title use, with age and sex controlled for. Beliefs about demonstrating expertise, having earned the title, and advancing the profession were primary reasons for using the title, while concerns about patient confusion and therapeutic alliance were reasons for not using it. Both DPTs who did and did not report using the title 'doctor' commonly cited the impact on therapeutic alliance as justification.

CONCLUSIONS

A minority of our sample of U.S. DPTs use the title 'doctor' during patient-provider introductions, with significant variation across age, gender, and professional experience. Deciding whether to use the title was primarily based on their perceived effects on patient beliefs.

DISCUSSION

This is the first study to formally investigate how DPTs refer to themselves during patient-provider introductions. Understanding title use in healthcare can inform best practices during patient interactions. This study provides a foundation for future research on the impact of DPTs mentioning their doctoral title on patient experiences and outcomes.

The Placebo Effect in Exercise and Mental Health Research

This chapter describes the placebo effect in the context of physical activity and mental health. Following a brief historical overview, definitions for placebos, placebo effects, and related terminology are discussed. Next, three major methodological challenges posed from studying the placebo effect in the context of exercise are described. Additionally, the role of a primary psychological mechanism of placebo and nocebo effects - expectations - will be summarized through the lens of key terminology. Findings from relevant chronic and acute exercise studies that have measured or manipulated exercise-associated expectations will be presented. The chapter concludes with recommendations for controlling or quantifying the placebo effect in exercise and mental health research and its implications in clinical practice.

The Roles of Endogenous Opioids in Placebo and Nocebo Effects: From Pain to Performance to Prozac

Placebo and nocebo effects have been well documented for nearly two centuries. However, research has only relatively recently begun to explicate the neurobiological underpinnings of these phenomena. Similarly, research on the broader social implications of placebo/nocebo effects, especially within healthcare delivery settings, is in a nascent stage. Biological and psychosocial outcomes of placebo/nocebo effects are of equal relevance. A common pathway for such outcomes is the endogenous opioid system. This chapter describes the history of placebo/nocebo in medicine; delineates the current state of the literature related to placebo/nocebo in relation to pain modulation; summarizes research findings related to human performance in sports and exercise; discusses the implications of placebo/nocebo effects among diverse patient populations; and describes placebo/nocebo influences in research related to psychopharmacology, including the relevance of endogenous opioids to new lines of research on antidepressant pharmacotherapies.

Expectations Come True: The Placebo Effect of Exercise on Affective Responses

Objective: This study investigated the placebo and nocebo effects of habitual and induced expectations. Methods: In Study 1, 95 participants (Mage = 19.65 ± 2.21 years, MBMI = 21.94 ± 2.55) were grouped according to habitual expectations (positive, neutral, or negative) and completed a 30-min moderate-intensity aerobic exercise, and their affective response, rating of perceived exertion (RPE), and heart rate variability (HRV) were measured before, during, and after the exercise. In Study 2, the participants from Study 1 were grouped according to induced expectations (control, positive, or negative) and completed a 30-min moderate-intensity aerobic exercise. Affective response, RPE, and HRV were measured before, during, and after exercise. Results: In Study 1, positive habitual expectations increased affective response during and after exercise [F(2, 92) = 2.959, p = .057, ηp2 = .060], and negative habitual expectations increased RPE during exercise [F(2, 92) = 5.174, p = .007, ηp2 = .101]. In Study 2, positive induced expectation increased affective response during [F(2, 86) = 5.492, p = .006, ηp2 = .113] and after exercise [F(2, 86) = 6.096, p = .003, ηp2 = .124] and was not affected by habitual expectation. Conclusion: The affective response during and after exercise is influenced by habitual and induced expectations. Positive expectations enhance affective benefits, while negative expectations reduce affective benefits.

Nocebo effects on motor performance: A systematic literature review

Directionally opposite to placebo effects are the nocebo effects that negatively impact people's thoughts, feelings, and actions. An important but scarcely studied aspect of everyday functioning is motor performance, in which nocebo effects might impair athletic skills and the much-needed purposeful daily movements and motor actions. The aim of this literature review is to unveil the nocebo effects on motor performance. Searched databases were PubMed, PsycINFO, and SPORTDiscus. Twenty-one articles, reporting 23 studies, met the eligibility criteria for inclusion in the current review. All reports exhibited "some" risk of bias. Of the 23 studies, 14 found a nocebo effect on motor performance, equivocal results emerged from two studies, and negative findings were reported in seven studies. Most (10/12) studies using a between-subjects design have reported a nocebo effect. The mean effect size was 0.60, suggesting a medium-to-large effect of nocebo intervention on motor performance. Based on this review, we conclude that nocebo effects do influence motor performance and can be evoked with negative verbal information. This effect may be more robust than the placebo effect but also depends on the type of motor performance, on the examined sample, and on the nocebo agent. Hence, nocebo effects should be recognized and controlled in empirical research on motor performance, and they should be prevented or extinguished in practical and therapeutic settings. More extensive examination of the nocebo effect on motor performance is warranted, especially using between-subjects research design and a "no agent" control condition.

Effectiveness of a dance-physiotherapy combined intervention in Parkinson's disease: a randomized controlled pilot trial

BACKGROUND

Physical therapies have been recommended as crucial components in Parkinson's disease (PD) rehabilitation.

OBJECTIVE

The study aims to examine the effectiveness of a new dance-physiotherapy combined intervention, called DArT method, in mild PD patients.

METHODS

A prospective, randomized, single-blind, controlled pilot trial was conducted on 38 mild PD patients under dopaminergic therapy. The intervention consisted in an add-on protocol: the control group received 1 h of conventional physiotherapy followed by 1 h of conventional physiotherapy each day, 3 times a week, for 5 weeks. The experimental group received 1 h of conventional physiotherapy followed by 1 h of dance class each day, 3 times a week, for 5 weeks. The week before and after the training period, patients were assessed for motor, cognitive, emotional, and sensory components of PD, with MDS-UPDRS-III as primary outcome measure.

RESULTS

DArT method was associated with a 2.72-point reduction in the post-treatment MDS-UPDRS-III total score compared to control group (95% CI - 5.28, - 0.16, p = 0.038, d = 0.71), and with a 2.16-point reduction in the post-treatment MDS-UPDRS-III upper body subscore (95% CI - 3.56, - 0.76, p = 0.003, d = 1.02). Conversely, conventional physiotherapy program was associated with a 2.95-point reduction in the post-treatment trait anxiety compared to the experimental group (95% CI 0.19, 5.71, p = 0.037, d = 0.70). Withdrawal and fall rates were equal to 0% in both groups.

CONCLUSION

DArT method showed to be safe, well accepted, and more effective than an intensive program of conventional physiotherapy in improving motor impairment in mild PD.

The placebo phenomenon and the underlying mechanisms

The clinical role of the placebo effect is a topic of increasing interest for the scientific community. Focus is shifting from the inert role of placebos in randomized controlled trials (RCTs) to potential effects in clinical applications, since the phenomenon is thought to be inherent in routine clinical practice, affecting therapy success rates. Mediation of the mind-brain-body relationship involves both psychosocial and neurobiological factors, the interaction of which comprises the placebo mechanisms. Psychosocial factors include environmentally induced expectations, reward expectations, and even conditioned responses to certain stimuli. Expectations also depend on previous experience of the patient with a similar procedure and can affect future responses. Moreover, the supportive bedside behavior of the clinician and the positive framing of information provided to the patient have proven to be of great importance, setting the foundations for reconsideration of standardized practices. Neurobiological mechanisms mediate these effects through neurotransmitter and neuromodulator pathways. The best understood mechanisms are those regulating non-opioid- and opioid-mediated analgesic responses that implicate specific brain regions of pain control and activation of endogenous opioids. Other responses concern, among others, hormonal control, motor performance, and antidepressant responses. Although mechanisms underlying placebo responses are not as yet completely elucidated, there is substantial evidence suggesting that placebo effects are indicative of healthy functioning of intact brain structures and occur through actual functional changes, and are not simply subjective symptom reports. These effects can be utilized in treatment optimization while maintaining an ethical and respectful manner toward the patient and the standardized disclosure procedures.

Time-Dependent Negative Effects of Verbal and Non-verbal Suggestions in Surgical Patients-A Study on Arm Muscle Strength

Introduction

The medical environment is full of suggestions that affect patients and their healing. Most of them inadvertently are negative, thus evoking nocebo effects. Recently, we have reported on the effect of such verbal and non-verbal suggestions as well as alternative formulations on maximal muscular arm strength in healthy volunteers. In the present study, we tested the same suggestions in patients at two time points to evaluate nocebo effects in a clinical situation and the impact of the approaching surgery date.

Methods

In 45 patients, maximal muscular strength during arm abduction was measured by dynamometry of the deltoid muscle group. One test was several days before and the second on the evening before surgery. Baseline values were compared to the performance after exposure to 18 verbal and non-verbal suggestions. The sequence of presumably negative and positive suggestions was randomized for each patient in order to avoid cumulation effects of immediate succession of two negatives. State anxiety was evaluated at both time points, and suggestibility was measured after surgery.

Results

Strong and statistically significant weakening effects were observed with all presumed negative suggestions from daily clinical practice including words of encouragement (91.4% of baseline), evaluation of symptoms (89.0%), announcement of a medical intervention (82.8%), a negative memory (86.5%), expectation of an uncertain future (82.8%), and non-verbal signals (87.7–92.2%). In contrast, alternative formulations did not interfere with muscular performance in most cases. A more pronounced effect was observed in the test repeated closer to the date of surgery, accompanied by a 15% higher anxiety level. The increase in anxiety correlated slightly with stronger weakening effects of suggestions, as did suggestibility.

Conclusions

Negative suggestions cause a decrease in arm muscle strength, i.e., a “weakening” of the patient. This effect is enhanced by an increase in anxiety as the time of treatment, like surgery, approaches. The reaction can be avoided by alternative formulations. These nocebo effects that are objectively measured and quantified by a decrease in arm muscle strength are more pronounced in patients, i.e., in a clinical situation, than in healthy volunteers.

Nocebo Effects on Perceived Muscle Soreness and Exercise Performance Following Unaccustomed Resistance Exercise: A Pilot Study

The purpose of this study was to investigate the effects of nocebo administration on perceived soreness and exercise performance following unaccustomed resistance exercise. Untrained males were randomly assigned to one of two treatments: (1) control or (2) negative-belief. For the negative-belief group, participants were given a capsule before exercise containing 400 mg of an inert substance (gluten-free cornstarch) and were told the supplement would increase muscle soreness. The control group received no treatment. An algometer and pain scale was used to obtain soreness, and a goniometer was used to measure elbow range of motion (ROM). Participants completed an eccentric bicep curl pyramid with their non-dominant arm. Rate of perceived exertion (RPE) and repetitions were recorded. Then, 48 h after the initial exercise bout, participants repeated all procedures. Perceived soreness, ROM, average RPE, and total repetitions performed were analyzed. Perceived soreness was significantly higher in both control and negative-belief groups 48 h after exercise (p < 0.001; η² = 0.23). ROM was significantly lower 48 h post in the negative-belief group (p = 0.004; d = 1.83) while no differences existed for controls (p = 0.999; d = 0.16). Average RPE was unaffected between groups (p = 0.282; η² = 0.07). Total repetitions were significantly lower 48 h post in the negative-belief group (p < 0.001; d = 2.51) while no differences existed for the controls (p = 0.999; d = 0.08). Findings suggest that 48 h after unaccustomed resistance exercise, negative expectation does not worsen soreness but hinders ROM and exercise performance.

Crisis of confidence averted: Impairment of exercise economy and performance in elite race walkers by ketogenic low carbohydrate, high fat (LCHF) diet is reproducible

INTRODUCTION

We repeated our study of intensified training on a ketogenic low-carbohydrate (CHO), high-fat diet (LCHF) in world-class endurance athletes, with further investigation of a "carryover" effect on performance after restoring CHO availability in comparison to high or periodised CHO diets.

METHODS

After Baseline testing (10,000 m IAAF-sanctioned race, aerobic capacity and submaximal walking economy) elite male and female race walkers undertook 25 d supervised training and repeat testing (Adapt) on energy-matched diets: High CHO availability (8.6 g∙kg-1∙d-1 CHO, 2.1 g∙kg-1∙d-1 protein; 1.2 g∙kg-1∙d-1 fat) including CHO before/during/after workouts (HCHO, n = 8): similar macronutrient intake periodised within/between days to manipulate low and high CHO availability at various workouts (PCHO, n = 8); and LCHF (<50 g∙d-1 CHO; 78% energy as fat; 2.1 g∙kg-1∙d-1 protein; n = 10). After Adapt, all athletes resumed HCHO for 2.5 wk before a cohort (n = 19) completed a 20 km race.

RESULTS

All groups increased VO2peak (ml∙kg-1∙min-1) at Adapt (p = 0.02, 95%CI: [0.35-2.74]). LCHF markedly increased whole-body fat oxidation (from 0.6 g∙min-1 to 1.3 g∙min-1), but also the oxygen cost of walking at race-relevant velocities. Differences in 10,000 m performance were clear and meaningful: HCHO improved by 4.8% or 134 s (95% CI: [207 to 62 s]; p < 0.001), with a trend for a faster time (2.2%, 61 s [-18 to +144 s]; p = 0.09) in PCHO. LCHF were slower by 2.3%, -86 s ([-18 to -144 s]; p < 0.001), with no evidence of superior "rebound" performance over 20 km after 2.5 wk of HCHO restoration and taper.

CONCLUSION

Our previous findings of impaired exercise economy and performance of sustained high-intensity race walking following keto-adaptation in elite competitors were repeated. Furthermore, there was no detectable benefit from undertaking an LCHF intervention as a periodised strategy before a 2.5-wk race preparation/taper with high CHO availability.

TRIAL REGISTRATION

Australia New Zealand Clinical Trial Registry: ACTRN12619000794101.

Time-course changes associated with PA lumbar mobilizations on lumbar and hamstring range of motion: a randomized controlled crossover trial

OBJECTIVE

We aimed to compare the post-intervention time-course changes in active knee extension (AKE) and active lumbar flexion (ALF) range of motion in response to unilateral posterior-anterior (UPA) mobilizations of the lumbar spine (L4/5 zygapophyseal).

METHODS

Twenty-four asymptomatic participants (maleness: 0.58, age [mean ± standard deviation]: 32 ± 8 years, body mass index 25.9 ± 2.6 kg m2) were recruited to a fully controlled crossover trial. Following either the intervention (L4/5 zygapophyseal mobilizations) or control, participants immediately performed the AKE and ALF tests, which were also performed at baseline. Subsequent tests were made at intervals of 5, 10, 15, 20, 25, 30, 45 and 60 min.

RESULTS

After adjustment for baseline (mean AKE: 37.2° from full extension, mean ALF: 14.37 cm), sex and age, UPA lumbar mobilizations had a most likely moderate effect on AKE (9.8° closer to full extension; ±1.9) and a likely moderate effect on ALF (1.34 cm; ±90% confidence limits 0.43). The magnitude of the AKE effect became most likely small 20-min posttreatment (5.3; ±1.7) and possibly small/possibly trivial 60-min posttreatment (2.1; ±1.4). For ALF, the magnitude of the effect became most likely small 15-min posttreatment (0.76; ±0.25), possibly small/possibly trivial 25-min posttreatment (0.38; ±0.18) and likely trivial 60-min posttreatment (0.26; ±1.8).

DISCUSSION

UPA lumbar mobilizations increased lumbar Range of Motion and hamstring extensibility by a moderate magnitude, with the effect reducing after 10-20-min posttreatment. Clinicians should consider these time-course changes when applying UPA lumbar mobilizations. Clinical Trials Registry: NCT03273400 Evidence Level: 2b.

Nocebo Effects on Muscular Performance - An Experimental Study About Clinical Situations

Introduction: Nocebo effects are not only seen in studies of pharmacology and placebo/nocebo research but also in clinical everyday situations. For generation of objective and quantitative data on the impact of negative communication we have evaluated the immediate effects of common sentences, non-verbal signals and situations in the medical context on muscular performance. Methods: In an experimental study, 46 volunteers were tested by dynamometry of the deltoid muscle group to evaluate the maximal muscular strength during arm abduction. Baseline values were compared to performance after exposure to 18 verbal and non-verbal suggestions. Suggestions suspected to be negative were alternated with and compared to positively formulated alternatives. Results: Verbal and non-verbal communication produced significant effects on muscular performance, resulting mainly in weakening. The decrease in muscle strength after risk information for informed consent (91.4% of baseline) was absent, when benefits of the treatment were named coincidently. The weakening effect of asking about "pain" and "nausea" (89.4%), and of the announcement of medical interventions (91.7%) could be avoided with alternative wording. Impairment of muscular performance was also observed with the nocebo-inducers negative memory (89.5%) or uncertain future (93.3%), in contrast to a positive memory or the orientation into the presence. Non-verbal suggestions like overhead anesthesia induction (89.9%), a transport in strict flat supine position (89.1%), or a view from the window to a parking lot (94.1%) significantly reduced maximal muscle strength, whereas face-to face induction, half-sitting position and a view into the landscape did not. 8 out of 9 tested clinical situations reduced maximal arm muscle strength significantly, whereas alternative formulations did not. Conclusion: This study describes a quick, simple and uniform test using objective measurement of maximal muscle strength to allow for identification, quantification, and comparison of negative suggestions, regardless of their specific content and effect. Muscle strength is a clinically relevant parameter with regard to early mobilization, risk of falling and sufficient breathing. Furthermore, the observed impairment of muscular performance could reflect a general "weakening effect" of negative suggestions. In addition, the test facilitates development and verification of appropriate alternatives to prevent nocebo effects in patients, thereby improving patient communication.

The interplay of exercise, placebo and nocebo effects on experimental pain

Over the last few decades, placebo, and nocebo effects in general, have been investigated at rest. This proposed study explores whether they could work even when the experience of pain occurs during a movement. Exercise itself can have a hypoalgesic effect, suggesting that placebo- and exercise-induced hypoalgesia could foster pain reduction. In the present study, we investigated the interplay of exercise, placebo and nocebo effects on pain. To this aim, we developed a machine-controlled isotonic motor task to standardize the exercise across participants and used a well-validated model of placebo and nocebo manipulations with reinforced expectations via a conditioning procedure including visual cues paired with heat painful stimulations. Participants reported expectations and pain on a trial-by-trial basis. We found that the standardized isotonic exercise elicited a reduction of pain intensity. Moreover, both exercise and placebo induced comparable hypoalgesic effects. When the exercise was added, placebo and nocebo effects were influenced by expectations but were not affected by fatigue or sex differences. Exercise-, placebo- and nocebo-induced pain modulation are likely to work through distinct mechanisms and neurophysiological research is needed to fully exploit the implications for sport, rehabilitation and pain management.

The placebo effect in the motor domain is differently modulated by the external and internal focus of attention

Among the cognitive strategies that can facilitate motor performance in sport and physical practice, a prominent role is played by the direction of the focus of attention and the placebo effect. Consistent evidence converges in indicating that these two cognitive functions can influence the motor outcome, although no study up-to-now tried to study them together in the motor domain. In this explorative study, we combine for the first time these approaches, by applying a placebo procedure to increase force and by manipulating the focus of attention with explicit verbal instructions. Sixty healthy volunteers were asked to perform abduction movements with the index finger as strongly as possible against a piston and attention could be directed either toward the movements of the finger (internal focus, IF) or toward the movements of the piston (external focus, EF). Participants were randomized in 4 groups: two groups underwent a placebo procedure (Placebo-IF and Placebo-EF), in which an inert treatment was applied on the finger with verbal information on its positive effects on force; two groups underwent a control procedure (Control-IF and Control-EF), in which the same treatment was applied with overt information about its inefficacy. The placebo groups were conditioned about the effects of the treatment with a surreptitious amplification of a visual feedback signalling the level of force. During the whole procedure, we recorded actual force, subjective variables and electromyography from the hand muscles. The Placebo-IF group had higher force levels after the procedure than before, whereas the Placebo-EF group had a decrease of force. Electromyography showed that the Placebo-IF group increased the muscle units recruitment without changing the firing rate. These findings show for the first time that the placebo effect in motor performance can be influenced by the subject’s attentional focus, being enhanced with the internal focus of attention.

Explicit Education About Exercise-Induced Hypoalgesia Influences Pain Responses to Acute Exercise in Healthy Adults: A Randomized Controlled Trial

The mechanisms through which acute exercise reduces pain (ie, exercise-induced hypoalgesia [EIH]) are poorly understood. This study aimed to determine if education about EIH affected pain responses after acute exercise in healthy adults. Participants received 15 minutes of education either about EIH (intervention, n = 20) or more general education about exercise and pain (control, n = 20). After this, the participants' knowledge and beliefs about exercise and pain were assessed. Pressure pain thresholds were then measured before and after 20 minutes of cycle ergometer exercise. Compared with the control group, the intervention group believed more strongly that pain could be reduced by a single session of exercise (P = .005) and that the information they had just received had changed what they thought about the effect of exercise on pain (P = .045). After exercise, pressure pain threshold increased in both groups, but the median increase was greater in the intervention group compared with the control group (intervention = .78 kg/cm², control = .24 kg/cm², P = .002, effect size [r] of difference = .49). These results suggest that cognitive processes in the appraisal of pain can be manipulated to influence EIH in healthy adults.

PERSPECTIVE

This study shows that preceding a bout of exercise with pain education can alter pain responses after exercise. This finding has potential clinical implications for exercise prescription for people with chronic pain whereby pain education before exercise could be used to improve pain responses to that exercise.

Factors influencing the outcome of deep brain stimulation: Placebo, nocebo, lessebo, and lesion effects

Deep brain stimulation (DBS) is a well-established treatment option for movement disorders, especially for Parkinson's disease (PD). There is a need to determine the role of expectation of benefit and the use of placebo to better understand the effects of electrode placement including the (micro)lesion effect. These factors must be understood to better interpret and attribute the therapeutic value of DBS. In this review, we critically present currently available data on the placebo, nocebo, lessebo, and lesion effects in the context of DBS. We provide a discussion of strategies that have the potential for controlling these effects in the setting of future DBS trials. We conclude that there is a need to standardize definitions for nocebo and (micro)lesion effects and that there are intrinsic limitations in defining the effect of expectation of benefit in DBS. These issues will be challenging to overcome especially with current technology and available study designs. New stimulation paradigms, better study designs, and the use of adaptive closed-loop DBS devices may facilitate a more accurate assessment of the placebo, nocebo, and lessebo effects in future DBS trials.

The Impact of Treatment of Overactive Bladder on Physical Activity Limitations

PURPOSE

To determine if treatment of overactive bladder (OAB) can improve self-reported limitations in physical activity in women.

MATERIALS AND METHODS

This is a prospective study of women with OAB treated with flexible-dose fesoterodine therapy and standardized behavioral counseling. Subjects were evaluated at baseline and 8 weeks post-treatment. Physical activity scores were assigned using two questions of the Short Form 12 (SF-12) and categorized into three levels of physical activity (no limitations, moderate limitations, severe limitations). Response of urinary symptoms to treatment at 8 weeks was measured using the Patient Global Impression of Improvement. Physical activity limitations at baseline and 8 weeks were compared.

RESULTS

We recruited 137 women. At baseline, 71 (52%) women had no limitations, 34 (25%) had moderate, and 32 (23%) had severe physical limitations. Eight weeks after treatment, the proportion of women reporting severe limitations in physical activity was significantly lower with 71 (52%) women reporting no limitations, 50 (36%) reporting moderate, and 16 (12%) reporting severe limitations in physical activity (p = 0.001). At 8 weeks, the proportion of women with no limitations in physical activity was higher in responders than nonresponders (52% vs. 33%), and the proportion of women with severe restriction was lower in responders (13% vs. 17%), although there was no significant difference between the groups (p = 0.24), which both showed overall improvement in physical activity limitations.

CONCLUSION

Treatment of OAB is associated with a decrease in perceived physical activity limitations; however, this is not directly associated with improvement in urinary symptoms.

Enhance placebo, avoid nocebo: How contextual factors affect physiotherapy outcomes

INTRODUCTION

Placebo and nocebo represent complex and distinct psychoneurobiological phenomena in which behavioural and neurophysiological modifications occur together with the application of a treatment. Despite a better understanding of this topic in the medical field, little is known about their role in physiotherapy.

PURPOSE

The aim of this review is: a) to elucidate the neurobiology behind placebo and nocebo effects, b) to describe the role of the contextual factors as modulators of the clinical outcomes in rehabilitation and c) to provide clinical and research guidelines on their uses.

IMPLICATIONS

The physiotherapist's features, the patient's features, the patient-physiotherapist relationship, the characteristics of the treatment and the overall healthcare setting are all contextual factors influencing clinical outcomes. Since every physiotherapy treatment determines a specific and a contextual effect, physiotherapists should manage the contextual factors as a boosting element of any manual therapy to improve placebo effects and avoid detrimental nocebo effects.