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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
Individualised Medication Effectiveness Tests for Chronic Pain.
Scientific title
An Individualised Medication Effectivenesss Test (n-of-1 trial) to evaluate the effects of ibuprofen and/or paracetamol in the treatment of chronic pain.
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Chronic pain. 709 0
Condition category
Condition code
Alternative and Complementary Medicine 786 786 0 0
Pain management

Study type
Description of intervention(s) / exposure
The Centre for General Practice (CGP) at the University of Queensland Medical School operates the IMET Service. IMETs (Individualized Medication Effectiveness Tests) are designed to determine which medications are best for individuals.

Some pain medications work differently for different people, and this means that some people taking medicines for chronic pain aren't getting any benefit from them. It is very difficult for doctors to find out which medicine is best just by trying them out one after the other because this isn't very reliable. It is much better to compare different medications objectively with an IMET.

An IMET is essentially a short medical trial lasting 6 or 12 weeks in which a medication is alternated on a weekly basis with either placebo (identical in appearance but with no effect) or another pain medication. Neither IMET Service staff nor the patient is aware of which weeks they are taking the real medicine. The patient is asked to record how they feel in short diaries during these periods. We can also compare two real medications in the same way.

After the IMET, the order of real and placebo medication is compared to the diary recordings are the results are used to determine if the medication benefits that person individually. If the patient says that they feel better when they are taking the real medicine then he/she is a responder. If there is no real difference between the way the patient feels when they are taking the placebo and the real medicine, then the medication isn't likely to be doing them any good. We call these people 'non-responders'.

If a patient is a responder, they can keep on taking the medication and feel confident that it is the better one for them. If they are a non-responder, another medication will be of more benefit. Using the IMET process, it is possible for a doctor and patient to find the best medication to treat chronic pain for the individual patient.

This trial offers IMETs for Actiprofen and Panadol, two common pain medicines. The reason for this is that some anti-inflammatory pain medications produce unwanted side effects for some people. If it is possible for people to have good pain relief from paracetamol or Actiprofen, or both, then this is a better option. This also has the potential to save the government health budget substantial amounts of money.
Intervention code [1] 664 0
Treatment: Drugs
Comparator / control treatment
Control group

Primary outcome [1] 1002 0
To improve therapeutic decision making about chronic pain medications, by educating the doctor and the patient in the use of Individualised Medication Effectiveness Test methodology for objective individual patient decision making
Timepoint [1] 1002 0
Secondary outcome [1] 1889 0
To evaluate individual patient responses to medication in terms of relief of chronic pain symptoms, and immediate side-effect profile.
Timepoint [1] 1889 0
Patients record responses to medication in a daily diary, and side-effects are recorded weekly.

Key inclusion criteria
A clinical diagnosis of chronic pain with symptoms of sufficient severity to warrant consideration of long-term medication, in the opinion of the attending practitioner. Many such patients may already be on such medication, but either the attending medical practitioner or the patient is uncertain of the effectiveness of their medication or medication dose.
Minimum age
Not stated
Maximum age
Not stated
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
No exclusion criteria

Study design
Purpose of the study
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 870 0
Commercial sector/Industry
Name [1] 870 0
Address [1] 870 0
Country [1] 870 0
Funding source category [2] 871 0
Name [2] 871 0
University of Queensland
Address [2] 871 0
Country [2] 871 0
Primary sponsor type
University of Queensland
Secondary sponsor category [1] 737 0
Commercial sector/Industry
Name [1] 737 0
Address [1] 737 0
Country [1] 737 0
United Kingdom

Ethics approval
Ethics application status
Ethics committee name [1] 2144 0
University of Queensland
Ethics committee address [1] 2144 0
Ethics committee country [1] 2144 0
Date submitted for ethics approval [1] 2144 0
Approval date [1] 2144 0
Ethics approval number [1] 2144 0
Ethics committee name [2] 2145 0
Department of Veterans' Affairs
Ethics committee address [2] 2145 0
Ethics committee country [2] 2145 0
Date submitted for ethics approval [2] 2145 0
Approval date [2] 2145 0
Ethics approval number [2] 2145 0
Ethics committee name [3] 2146 0
Princess Alexandra Hospital
Ethics committee address [3] 2146 0
Ethics committee country [3] 2146 0
Date submitted for ethics approval [3] 2146 0
Approval date [3] 2146 0
Ethics approval number [3] 2146 0
Ethics committee name [4] 2147 0
Illawarra Area Health Service
Ethics committee address [4] 2147 0
Ethics committee country [4] 2147 0
Date submitted for ethics approval [4] 2147 0
Approval date [4] 2147 0
Ethics approval number [4] 2147 0
Ethics committee name [5] 2148 0
University of Woolongong
Ethics committee address [5] 2148 0
Ethics committee country [5] 2148 0
Date submitted for ethics approval [5] 2148 0
Approval date [5] 2148 0
Ethics approval number [5] 2148 0
Ethics committee name [6] 2149 0
Port Kembla Hospital
Ethics committee address [6] 2149 0
Ethics committee country [6] 2149 0
Date submitted for ethics approval [6] 2149 0
Approval date [6] 2149 0
Ethics approval number [6] 2149 0
Ethics committee name [7] 2150 0
Royal Children's Hospital
Ethics committee address [7] 2150 0
Ethics committee country [7] 2150 0
Date submitted for ethics approval [7] 2150 0
Approval date [7] 2150 0
Ethics approval number [7] 2150 0

Brief summary
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 35194 0
Address 35194 0
Country 35194 0
Phone 35194 0
Fax 35194 0
Email 35194 0
Contact person for public queries
Name 9853 0
Norma McNairn
Address 9853 0
Individualised Medication Effectiveness Testing (IMET) Service
Discipline of General Practice
School of Medicine
University of Queensland
Level 2
Edith Cavell Building
Herston QLD 4006
Country 9853 0
Phone 9853 0
+61 7 33464835
Fax 9853 0
+61 7 33655130
Email 9853 0
Contact person for scientific queries
Name 781 0
Associate Professor Geoff Mitchell
Address 781 0
Individualised Medication Effectiveness Testing (IMET) Service
Discipline of General Practice
School of Medicine
University of Queensland
Level 2
Edith Cavell Building
Herston QLD 4006
Country 781 0
Phone 781 0
+61 7 33655504
Fax 781 0
+61 7 33655130
Email 781 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary