Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625001097437
Ethics application status
Approved
Date submitted
12/09/2025
Date registered
8/10/2025
Date last updated
8/10/2025
Date data sharing statement initially provided
8/10/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
What happens in the brains of both the patient and the chiropractor during chiropractic care?
Scientific title
Neural Synchrony and Therapeutic Alliance: A Hyperscanning EEG Study in Chiropractic Care in the patient and the chiropractor
Secondary ID [1] 315136 0
None
Universal Trial Number (UTN)
U1111-1328-4859
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Musculoskeletal condition 338560 0
Condition category
Condition code
Musculoskeletal 334864 334864 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants in the intervention group will receive chiropractic care (Single session), including spinal adjustments performed by a registered chiropractor. A registered chiropractor will assess the entire spine, and both sacroiliac joints will be assessed for vertebral subluxation by a registered chiropractor with at least five years of clinical experience. The clinical indicators that will be used to assess the function of the spine before spinal adjustment intervention include assessing for joint tenderness to palpation manually palpating for a restricted intersegmental range of motion, assessing for palpable asymmetric intervertebral muscle tension, and any abnormal or blocked joint play and end-feel of the joints. Chiropractors use these biomechanical characteristics as clinical indicators of spinal dysfunction and vertebral subluxation. All spinal adjustments carried out in this study will be high-velocity, low-amplitude thrusts to the spine or pelvic joints, a standard adjusting technique used by chiropractors. The mechanical properties of chiropractic adjustment have been investigated; and although the actual force applied to the patient's spine depends on the chiropractor, the patient, and the spinal location of the subluxation, the general shape of the force-time history of spinal adjustments is very consistent and the duration of the thrust is always less than 200 milliseconds. The whole assessment and intervention will take around 45 minutes.

EEG: EEG will be recorded before, during, and after the intervention session using a portable 64-channel, research-grade system (gel-based cap with active electrodes). Two separate EEG units will be used for the participants and the chiropractors, with caps appropriately sized for each wearer. A trained EEG researcher will apply, check impedances, and monitor the recording throughout, under the oversight of the study’s lead. The anticipated EEG monitoring duration during intervention is ~10-15 minutes per session, with continuous artifact monitoring and standard safety/hygiene procedures followed.

Materials: Before enrolment, participants will receive a Participant Information Sheet and Consent Form (and a brief pre-visit guidance sheet), while treating chiropractors will use a standardized procedure checklist and case-report form aligned with the study rubric.

Setting: All sessions will be delivered at the New Zealand College of Chiropractic (NZCC) Chiropractic Centre (Auckland).

Adherence/fidelity: Because this is a single-session intervention, adherence will be defined as attendance and completion of the visit; this will be verified via clinic scheduling logs and a signed clinician checklist documenting each protocol step, with any deviations recorded in the case-report form.
Intervention code [1] 331759 0
Rehabilitation
Intervention code [2] 331760 0
Treatment: Other
Comparator / control treatment
The control intervention will involve passive and active head and spine movements akin to chiropractic spinal assessment techniques but without joint pre-loading or high-velocity, low-amplitude (HVLA) thrust adjustments. Participants will be positioned similarly to standard adjustment setups; however, movements will be deliberately terminated before reaching end-range-of-motion to prevent joint loading. Avoiding joint loading is critical as such loading has been shown to alter proprioceptive input significantly. Thus, the control intervention will serve as a physiological control, accounting for cutaneous, muscular, and vestibular sensory inputs typically involved in chiropractic sessions but distinctly excluding actual spinal adjustments.

EEG: EEG will be recorded before, during, and after the intervention session using a portable 64-channel, research-grade system (gel-based cap with active electrodes). Two separate EEG units will be used for the participants and the chiropractors, with caps appropriately sized for each wearer. A trained EEG researcher will apply, check impedances, and monitor the recording throughout, under the oversight of the study’s lead. The anticipated EEG monitoring duration during intervention is ~10-15 minutes per session, with continuous artifact monitoring and standard safety/hygiene procedures followed.
Control group
Active

Outcomes
Primary outcome [1] 342492 0
Inter-brain connectivity and Inter-brain synchrony
Timepoint [1] 342492 0
In both intervention and control groups, data assessment will be conducted at three-time points: pre-session baseline (5-10 minutes), during the chiropractic adjustment (5-10 minutes), and post-session follow-up (10 minutes).
Secondary outcome [1] 451033 0
Quality of the therapeutic alliance
Timepoint [1] 451033 0
After the intervention or control session

Eligibility
Key inclusion criteria
Inclusion Criteria:
- Adults aged 18 years and above
- Practice members with mild to moderate spinal musculoskeletal issues (e.g., neck, mid and lower back pain) seeking chiropractic care.
- Ability to provide informed consent and tolerate EEG recording.
- No prior EEG abnormalities or contraindications to manual therapy.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion Criteria:
- Have any contraindications to chiropractic adjustments (such as a history of recent spinal fractures, inflammatory disease such as rheumatoid arthritis, or a recent history of cancer).
- Have any neurological disorder such as stroke, seizures
- Have a history of head injury with ongoing symptoms.
- Have metal implants in their head
- Have severe psychiatric disorders (e.g., schizophrenia)
- Are experiencing acute pain or serious injury needing urgent care
- Have substance use disorders (ongoing problems related to alcohol or drug misuse)
- Have major health conditions (e.g., heart disease)
- Have a history of aggressive behaviour, suicidal thoughts, or difficulty cooperating.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Following recruitment, screening and informed consent, eligible participants will be randomly allocated to either intervention or control group using a randomisation schedule generated by a computer system. This will be held by a third party.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The minimizer (Microsoft Corp., Redmond, WA) will create the randomization sequence with a 1:1 allocation to the intervention or control groups.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
13/10/2025
Actual
Date of last participant enrolment
Anticipated
28/11/2025
Actual
Date of last data collection
Anticipated
15/12/2025
Actual
Sample size
Target
30
Accrual to date
Final
Recruitment outside Australia
Country [1] 27351 0
New Zealand
State/province [1] 27351 0

Funding & Sponsors
Funding source category [1] 319713 0
Other
Name [1] 319713 0
New Zealand College of Chiropractic
Country [1] 319713 0
New Zealand
Primary sponsor type
Other
Name
New Zealand College of Chiropractic
Address
Country
New Zealand
Secondary sponsor category [1] 322221 0
None
Name [1] 322221 0
Address [1] 322221 0
Country [1] 322221 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 318266 0
Northern B Health and Disability Ethics Committee 
Ethics committee address [1] 318266 0
Ethics committee country [1] 318266 0
New Zealand
Date submitted for ethics approval [1] 318266 0
19/08/2025
Approval date [1] 318266 0
26/09/2025
Ethics approval number [1] 318266 0
2025 EXP 23740

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 143638 0
Dr Imran Khan Niazi
Address 143638 0
New Zealand College of Chiropractic 6 Harrison Road Mount Wellington Auckland 1060
Country 143638 0
New Zealand
Phone 143638 0
+64 2102847764
Fax 143638 0
Email 143638 0
[email protected]
Contact person for public queries
Name 143639 0
Imran Khan Niazi
Address 143639 0
New Zealand College of Chiropractic 6 Harrison Road Mount Wellington Auckland 1060
Country 143639 0
New Zealand
Phone 143639 0
+64 2102847764
Fax 143639 0
Email 143639 0
[email protected]
Contact person for scientific queries
Name 143640 0
Imran Khan Niazi
Address 143640 0
New Zealand College of Chiropractic 6 Harrison Road Mount Wellington Auckland 1060
Country 143640 0
New Zealand
Phone 143640 0
+64 2102847764
Fax 143640 0
Email 143640 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.