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CompletedNCT04975659Updated May 19, 2023

Placebo Versus Nocebo: Effects on Pain and Anxiety During Local Anaesthetic Infiltration in Parturient Undergoing Elective Caesarean Delivery

An interventional study of Placebo and Nocebo effect in Communication, sponsored by Universiti Kebangsaan Malaysia Medical Centre. Completed at 1 site in Malaysia. Open to female participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2023-05-19.

Sponsored by Universiti Kebangsaan Malaysia Medical Centre · Not applicable, Interventional, and Supportive care

From the registry’s dates

  • Registered 11 months after the study started (first participant enrolled Jul 2020, registered Jul 2021).
Phase
Not applicable
Study type
Interventional
Enrollment
76
Allocation
Randomized
Ages
18 Years to 45 Years
Sex
Female
01

Study summary

This randomized trial compared placebo and nocebo effect over anaesthetist-patient communication on pain and anxiety score during local anaesthetic (LA) skin infiltration in parturient undergoing caesarean delivery under regional anaesthesia (RA). A secondary objective was to determine if education level and previous RA experience affect pain and anxiety scores. Parturients scheduled for elective caesarean delivery were randomised into Placebo (P) or Nocebo (N) group. Baseline Amsterdam Preoperative Anxiety \& Information Scale (APAIS0) were obtained. Standardised scripts describing the LA skin infiltration for RA were used during the pre-anaesthetic review. (N) group were explained with words like "pain, prick, sharp" while words like "numb, comfort, tolerable" were used in the (P) group, avoiding "painful" expressions. The same scripts will be repeated before skin infiltration during the RA procedure. On the day of surgery, a second (APAIS1) was obtained upon arrival to the theatre. Pain score using the numerical rating scale (NRS) was assessed after LA infiltration.

Read the detailed description

We randomised participants into either the nocebo (N) or placebo (P) group. We obtained a baseline anxiety score (APAIS0) using the Amsterdam Preoperative Anxiety and Information Scale (APAIS) during the pre-anaesthesia visit. Following that, we informed subjects in the N group a negative suggestion, using the following script: "During the local anaesthetic injection, you are going to feel a sharp prick at your back; this is usually the most painful part of the procedure". On the other hand, we used a positive suggestion on the P group: "We will administer some local anaesthetic to numb your back; this will allow the procedure to be more comfortable and tolerable for you." We obtain a second anxiety score (APAIS1) in the operating theatre before the caesarean section. We carried out either spinal anaesthesia or continuous spinal epidural according to standard hospital protocol and indication. Before the LA skin infiltration, the anaesthetist repeats the same script to the subjects according to the prior randomisation. Five millilitres of lignocaine 2% is injected intradermally and subcutaneously by the anaesthetist into interspinous space in a single pass through a 22-gauge needle to create a skin wheal.

During the LA infiltration, only the attending anaesthetist performing the procedure gave participants verbal instructions; other personnel remained silent throughout. We recorded the presence of vocalisation of pain, withdrawal movement or facial grimacing. Immediately after the LA infiltration, a blinded and trained general anaesthetic nurse or personnel enters the operating theatre to assess the subjects' pain score using the numerical rating scale (NRS). After collection of the pain score, the anaesthetist performed the remaining anaesthetic procedure as per clinical routine.

02

Conditions studied

  • Communication

Keywords

  • Placebo
  • Nocebo
  • Pain
  • Anxiety
  • Local Skin Infiltration
03

In context

Lead sponsor

Universiti Kebangsaan Malaysia Medical Centre is the lead sponsor of 57 studies on the registry; 7 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 45 Years
Sexes eligible
Female
Accepts healthy volunteers
No

Inclusion criteria

  • American Society of Anaesthesiology (ASA) II category parturient listed for elective caesarean delivery.
  • Can understand intended verbal communication

Exclusion criteria

Exclusion Criteria:

  • receiving any form of analgesia within 6 hours before the study
  • chronic pain,
  • anxiety disorders
  • allergy to Local Anaesthetic drugs
05

Study design

Phase
Not applicable
Primary purpose
Supportive care
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Outcomes assessor)
Enrollment
76 participants (actual)

Study arms

  • Active comparator
    Nocebo

    We informed subjects in the N group a negative suggestion, using the following script: "During the local anaesthetic injection, you are going to feel a sharp prick at your back; this is usually the painful part of the procedure"

    Behavioral: Placebo and Nocebo effect

  • Placebo comparator
    Placebo

    We informed subjects in the P group a positive suggestion, using the following script: "We will administer some local anaesthetic to numb your back; this will allow the procedure to be more comfortable and tolerable for you."

    Behavioral: Placebo and Nocebo effect

Interventions

  • BehavioralPlacebo and Nocebo effect

    Positive suggestion and words is used on Placebo group Negative suggestion and words is used on Nocebo group

06

What researchers measure

Primary outcomes

  1. Pain score

    Pain score during local anaesthetic infiltration using Numerical Rating Scale (NRS) (range 0-10) where 0 is "no pain at all" and 10 is " worst pain ever felt"

    Time frame: Throughout study completion, average of 10 months

  2. Baseline anxiety score

    Validated questionnare using the Amsterdam Preoperative Anxiety \& Information Scale. (APAIS) (Range 6-30). Higher scores mean higher anxiety level

    Time frame: Through study completion, average of 10 months

  3. Preoperative anxiety score

    Validated questionnare using the Amsterdam Preoperative Anxiety \& Information Scale. (Range 6-30). Higher scores mean higher anxiety level

    Time frame: Through study completion, average of 10 months

Secondary outcomes

  1. Association of Education level on Pain and anxiety score

    Correlation between subjects education level on pain score (NRS) and anxiety score (APAIS)

    Time frame: Through study completion, average of 10 months

  2. Association of past history of regional anesthesia on Pain and anxiety score

    Correlation between subjects previous experience of regional anesthesia on pain score (NRS) and anxiety score (APAIS)

    Time frame: Through study completion, average of 10 months

07

Study locations

1 site
  • Hospital Canselor Tuanku Muhriz,
    Cheras, Kuala Lumpur 56000, Malaysia
08

References and documents

Publications

  • Mohd Fahmi Z, Lai LL, Loh PS. Validation of the Malay version of the Amsterdam Preoperative Anxiety and Information Scale (APAIS). Med J Malaysia. 2015 Aug;70(4):243-8. PubMed 26358022 ↗
  • Dutt-Gupta J, Bown T, Cyna AM. Effect of communication on pain during intravenous cannulation: a randomized controlled trial. Br J Anaesth. 2007 Dec;99(6):871-5. doi: 10.1093/bja/aem308. Epub 2007 Oct 30. PubMed 17977860 ↗
  • Varelmann D, Pancaro C, Cappiello EC, Camann WR. Nocebo-induced hyperalgesia during local anesthetic injection. Anesth Analg. 2010 Mar 1;110(3):868-70. doi: 10.1213/ANE.0b013e3181cc5727. Epub 2009 Dec 30. PubMed 20042440 ↗
  • Moerman N, van Dam FS, Muller MJ, Oosting H. The Amsterdam Preoperative Anxiety and Information Scale (APAIS). Anesth Analg. 1996 Mar;82(3):445-51. doi: 10.1097/00000539-199603000-00002. PubMed 8623940 ↗

Individual participant data

Plan to share: Undecided

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 19, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04975659
Lead sponsor
Universiti Kebangsaan Malaysia Medical Centre
Responsible party
Rufinah Teo (Lecturer and Consultant Anesthesiologist , Department of Anesthesia and Intensive Care, Universiti Kebangsaan Malaysia Medical Centre) — Principal investigator
First posted
Jul 23, 2021
Start date
Jul 13, 2020
Primary completion
May 21, 2021
Completion
May 28, 2021
Last update
May 19, 2023

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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