Explaining placebo effects in an online survey study: Does 'Pavlov' ring a bell?

Open-label placebo for non-specific pain in the emergency department (OLP EM): study protocol for a mixed-method randomised control feasibility study in Switzerland

INTRODUCTION

Non-specific pain (NSP), defined as pain without a clear pathological cause, is a common presentation in the emergency department (ED). There is no universally accepted analgesic strategy, but non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen are often prescribed. However, the established efficacy of NSAIDs for NSP is limited. Additionally, NSAIDs are associated with an increased risk of upper gastrointestinal bleeding, acute kidney injury and cardiovascular events, such as myocardial infarction and stroke. There is increasing evidence supporting the analgesic effects of open-label placebo (OLP), defined as placebo administered to patients without deception, in a broad variety of settings. Accordingly, OLP could be a safer, effective analgesic treatment option for NSP. To our knowledge, this is the first study investigating the feasibility of OLP for NSP in the ED. Therefore, our primary objective is to assess whether OLP is a feasible treatment option in this setting.

METHODS AND ANALYSIS

Patients diagnosed with acute NSP will be prospectively recruited at discharge in the ED at the University Hospital of Basel, Switzerland. Patients treated with pain medication for >7 days prior to ED visit or with chronic pain will be excluded. Patients will be randomised to receive either OLP (intervention) or ibuprofen (control). Rescue medication will be ibuprofen in both groups. Daily online self-assessment will take place during the first 7 days after the baseline visit as well as on day 30. A qualitative interview will be conducted on day 30. The primary outcome is feasibility, consisting of acceptability, adherence to the protocol and patient satisfaction. Clinical outcomes will focus on pain intensity and interference according to the Brief Pain Inventory Short Form as well as adverse events.

ETHICS AND DISSEMINATION

The study protocol has received approval from the ethics committee for Northwestern and central Switzerland (EKNZ; project ID 2024-00089). The results will be disseminated in peer-reviewed journals and at scientific conferences.

TRIAL REGISTRATION NUMBER

Swiss National Clinical Trials Portal (SNCTP000005852); Clinicaltrial.gov (NCT06408519).

Do patients with fibromyalgia syndrome and healthy people differ in their opinions on placebo effects in routine medical care?

OBJECTIVES

Placebo effects can relieve acute and chronic pain in both research and clinical treatments by learning mechanisms. However, the application of placebo-based treatment strategies in routine medical care is questioned. The current study investigated the opinions of patients with fibromyalgia and healthy controls regarding learning of placebo effects and their practical applications.

METHOD

An online survey asked 158 age- and sex-matched adult patients and controls (79 per group) to rate the perceived influence of various placebo learning mechanisms on pain relief, and the acceptability and perceived effectiveness of placebo-based strategies (open-label, closed-label, dose-extending, and treatment-enhancing strategies). Respondents' knowledge about placebo effects was obtained through a 7-item quiz.

RESULTS

The groups did not differ in the perceived influence of placebo learning mechanisms on pain relief (p = 0.217). Controls considered closed-label and treatment-enhancing strategies more acceptable than patients (p = 0.003 and p < 0.001), whereas controls perceived all strategies more effective. In both groups, closed-label strategies were significantly less acceptable than any other strategy (p-values < 0.001), and treatment-enhancing or dose-extending strategies were most acceptable. Higher acceptability was predicted by higher perceived effectiveness ratings (p < 0.001). Also, increased placebo knowledge was related to higher acceptability (p = 0.03) and perceived effectiveness (p < 0.001).

DISCUSSION

This survey suggests that both the medical history of patients and knowledge about placebo effects affect the acceptability and perceived effectiveness of placebo-based strategies. Furthermore, strategies that are transparent, assumed effective, or combined with existing medical treatments are deemed most acceptable. Keeping these factors in mind is essential for the clinical implementation of placebo-based strategies in routine medical care.

Negative lay perceptions of open-label placebo users may pose barriers to intervention adoption

BACKGROUND

Recent research has revealed that the use of specific medical interventions carries with it social stigma. This "intervention stigma" can pose an obstacle to the use and adoption of interventions that may otherwise be effective in managing medical conditions. Open-label placebos (OLPs) have been identified as a potential intervention for a variety of clinical and nonclinical conditions but are viewed with skepticism among lay populations.

PURPOSE

This online experimental study aimed to quantify intervention stigma associated with the use of OLP interventions for a medical condition within a warmth-competence framework of social perception.

METHODS

In an online experiment fielded in the USA (N = 541), we randomly assigned participants to read 1 of 4 vignettes about a patient who is administered an OLP intervention by a physician for chronic back pain. In each vignette, the patient's belief in and response to the treatment varied. After reading the vignette, participants rated the patient on several characteristics that captured perceptions of warmth and competence.

RESULTS

We found that patients who believed in the OLP intervention or reported improvement after taking it were perceived as less competent and warmer.

CONCLUSIONS

Our results suggest that the use of OLP interventions for medical conditions carries intervention stigma. We contend that this stigma poses an obstacle to the adoption of OLP interventions.

Would You Take an Open-Label Placebo Pill or Give One to Your Child? Findings from a Cross-Sectional Survey

Background

Open-label placebos (OLPs), honestly prescribed regarding their inert nature, have been associated with positive health-related effects in both children and adults. However, OLPs are not always perceived by laypeople as a viable treatment option.

Methods

A brief online survey with 806 adult participants (age range: 18-75 years; 29% parents) was conducted to identify predictor variables that are associated with the willingness to take an OLP pill (criterion 1) or to give an OLP to one's child (criterion 2). The survey covered aspects including the perceived plausibility of the treatment concept for both OLPs and deceptive placebos (DPs), self-reported knowledge about placebos, the expected effectiveness of OLPs in treating emotional/ somatic problems, and attitudes concerning taking pills in general. Multiple hierarchical regressions were carried out.

Results

The expected effectiveness of OLPs in alleviating both emotional and physical ailments and the plausibility of the treatment concepts for both OLPs and DPs significantly predicted the willingness to use OLPs (R2 = 0.485). A similar finding was observed when predicting the willingness to administer an OLP to one's child (R2 = 0.443).

Conclusion

Favorable expectations regarding the reduction of emotional and somatic symptoms with OLPs, along with a strong belief in the credibility of placebo mechanisms, play a vital role in influencing the willingness to accept this kind of treatment. These factors can be incorporated into psychoeducational programs.

Can open label placebos improve pain and gluten tolerance via open label placebos in fibromyalgia patients? A study protocol for a randomised clinical trial in an outpatient centre

INTRODUCTION

Fibromyalgia syndrome (FMS) is defined as a medical condition with chronic widespread musculoskeletal pain accompanied by mood disorders, fatigue and sleep disturbances. Treatment of this condition can often be challenging. As nutrition in general and nutritional interventions in the context of illness management become more and more important, current research also focuses on the relevance of diets for FMS, including gluten as field of interest. To date, there is no clear evidence that a gluten-free diet or other nutritional interventions are significantly important for the reduction of pain in the context of FMS. Only a very few studies show that FMS patients respond to a gluten-free diet and that cytokine production (also in FMS) can be reduced through the change. However, these studies have not investigated whether and to what extent cognitive factors, such as the expectation of symptom reduction triggered by diet, play a role. Recent research shows that treatment expectation plays an important role in the course of the disease and in the effectiveness of treatment approaches. For example, there are promising pain treatment options using open-label placebos (OLPs), which show that expectation alone, rather than the pharmacological substance of medication, can reduce pain experience. In our study protocol, we hypothesise that treatment expectation can be positively influenced by the given information regarding the placebos, resulting in improved treatment outcomes for pain and indigestions.

METHODS AND ANALYSIS

In this trial, patients with FMS will undergo a food challenge and take an OLP (patients will be informed about the placebo), followed by a 3-week OLP treatment. The subjects will be randomised into four groups: (a) gluten-free porridge+neutral OLP instructions; (b) gluten-free porridge+positive OLP instructions; (c) gluten-containing porridge+neutral OLP instructions and (d) gluten-containing porridge+positive OLP instructions. Patients will be recruited via different institutions and support groups in Hamburg. The inclusion criteria are (a) diagnosed FMS, (b) absence of wheat allergy, coeliac disease or pain-related red flags and (c) being a minimum age of 18 years. The study requires 100 subjects to assess the primary outcomes: pain intensity and occurence of indigestion. Secondary outcomes are functional capacity, treatment expectation, and different pain-related and inflammation-related blood parameters. The measure time points will be before and after the food challenge and before and after the 3-week OLP treatment.

ETHICS AND DISSEMINATION

Ethical approval was obtained in October 2021 from the Hamburg Medical Ethics Council. The results of the study will be disseminated through publications, presentations and conference meetings.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register (DRKS; DRKS00027130).

Placebos in pediatrics: A cross-sectional survey investigating physicians' perspectives

OBJECTIVE

Placebo responses are significantly higher in children than in adults, suggesting a potential underused treatment option in pediatric care. To facilitate the clinical translation of these beneficial effects, we explored physicians' current practice, opinions, knowledge, and likelihood of recommending placebos in the future.

METHODS

A cross-sectional web-based survey administered by REDCap was conducted at Boston Children's Hospital between October 2021 and March 2022. Physicians (n = 1157) were invited to participate through an email containing a link to a 23-item survey designed to assess physicians' attitudes and perceptions towards the clinical use of placebo in pediatrics.

RESULTS

From 207 (18%) returned surveys, 109 (9%) were fully completed. Most respondents (79%) believed that enhancing the therapeutic components that contribute to the placebo response may be a way of improving pediatric care. However, whereas most (62%) found placebo treatments permissible, only one-third reported recommending them. In pediatrics, placebos are typically introduced as a medicine that "might help" (43%). The most common treatments recommended to enhance placebo effects are physical therapy, vitamins, and over-the-counter analgesics. Physicians most frequently recommend placebos for occasional pain, headaches, and anxiety disorders. Finally, the great majority of physicians (87%) stated they would be more likely to recommend placebo treatments if there were safety and ethical guidelines for open-label placebos.

CONCLUSIONS

Placebo treatments seem permissible to physicians in pediatric care, but the development of safety and ethical guidelines may be necessary before physicians systematically incorporate the benefits of the placebo effect in pediatrics.

A qualitative study of imaginary pills and open-label placebos in test anxiety

BACKGROUND

The efficacy of open-label placebos (OLPs) has been increasingly demonstrated and their use holds promise for applications compatible with basic ethical principles. Taking this concept one step further an imaginary pill (IP) intervention without the use of a physical pill was developed and tested in a randomized controlled trial (RCT). To explore participants' experiences and views, we conducted the first qualitative study in the field of IPs.

METHODS

A reflexive thematic analysis (RTA) of semi-structured interviews with test anxious students (N = 20) was nested in an RCT investigating an IP and OLP intervention. In addition, open-ended questions from the RCT were evaluated (N = 114) to corroborate the RTA and pill characteristics were included to more accurately capture the IP experience.

RESULTS

Four key themes were identified: (1) attitude towards the intervention, (2) applicability of the intervention, (3) experience of effects, and (4) characteristics of the imagination. The IP intervention was well-accepted, easily applicable, and various effects, pill characteristics and appearances were described. While many participants did not desire a physical pill, either due to the absence of the imagination component or aversion to pills, the approach was considered to be cognitively and time demanding, which in turn, however, encouraged the establishment of a therapeutic ritual that protected against the increase in test anxiety during the preparation phase. OLP findings were comparable, and especially the importance of a treatment rationale was stressed in both groups, counteracting an initial ambivalent attitude. The RTA findings were supported by the open-ended questions of the RCT.

CONCLUSION

IPs appear to be a well-accepted and easily applicable intervention producing a variety of beneficial effects. Thus, the IP approach might serve as an imaginary based alternative to OLPs warranting further investigations on its application to harness placebo effects without a physical pill.

Lay perspectives of the open-label placebo rationale: a qualitative study of participants in an experimental trial

OBJECTIVES

To analyse participants' concepts about the open-label placebo (OLP) effect; to explore their views about the discussion points that are applied in conventional OLP trials and to examine their experiences of taking part in an OLP trial.

DESIGN

A qualitative study using thematic analysis of semistructured interviews that were nested within a randomised controlled trial investigating experimental OLP analgesia (registered at ClinicalTrials.gov: NCT02578420).

PARTICIPANTS

30 healthy adults who took part in the randomised controlled trial.

RESULTS

Participants mostly conceptualised placebo as something that is inert and requires deception in order to be effective. Interviewees used a broad definition of placebos, going beyond a conventional notion of sugar pills. In contrast to the conventional OLP rationale, participants seldom emphasised classical conditioning as a mechanism of placebo effects, stressing a variety of other well-established components through which placebos might be therapeutic, whereas the conventional OLP disclosures state that 'a positive attitude helps but is not necessary', participants in our study applied other attitudes, such as 'it's worth a try'. When asked about their experiences during the trial, the majority emphasised that the concept of OLP was completely novel to them. Participants were rather sceptical about the efficacy of the intervention.

CONCLUSION

Integrating lay perspectives into the scientific rationale of OLP treatments might enhance the plausibility and credibility of the rationale in ethical treatments.

TRIAL REGISTRATION NUMBER

NCT02578420.

Integrating Placebo Effects in General Practice: A Cross-Sectional Survey to Investigate Perspectives From Health Care Professionals in the Netherlands

Objectives: Placebo effects, beneficial treatment outcomes due to non-active treatment components, play an important role in the overall treatment response. To facilitate these beneficial effects it is important to explore the perspectives of health care professionals (HCPs) on the integration of placebo effects in clinical care. Three themes were investigated: knowledge about placebo effects and factors that contribute to these, frequency of placebo use, and attitudes toward acceptability and transparency of placebo use in treatment. Methods: A cross-sectional survey, according to the Checklist for Reporting Results of Internet E-Surveys guidelines and STrengthening the Reporting of OBservational Studies in Epidemiology (STROBE), was conducted in the Netherlands in 2020. The survey was conducted in two samples: a (nested) short survey in 78 nurses during working shifts (sample 1) and an extended online survey in 47 general HCPs e.g., medical psychologists, oncologists, surgeons (sample 2). Results: Respondents from both samples reported to be somewhat or quite familiar with placebo effects (24.0 and 47.2%, respectively). From the six placebo mechanisms that were presented, mind-body interaction, positive expectations, and brain activity involved in placebo effects were rated as the most influential factors in placebo effects [F_(5,119) = 20.921, p < 0.001]. The use of placebo effects was reported in 53.8% (n = 42) of the nurses (e.g., by inducing positive expectations), and 17.4% of the HCPs (n = 8 reported to make use of pure placebos and 30.4% of impure placebos (n = 14). Attitudes toward placebo use in treatment were acceptant, and transparency was highly valued (both up to 51%). Conclusions: The findings from this study address knowledge gaps in placebo effects in practice and provide insights in attitudes toward the integration of placebo effects from HCPs. Altogether, integrating these findings may potentially optimize treatment outcomes.