Autologous Chondrocyte Transplantation / Implantation Versus Existing treatments

Chondral defects
Which Hospitals?
Your Participation
Study Documents
Local Coordinators
Rehab Physios



Each participating site recruits an Independent Assessor (ideally a Physiotherapist) responsible for carrying out patient outcome assessments at the proper time points. This position would suit a member of the Physiotherapy Department at the hospital who can be released from duties when the assessments need to be carried out. As Independent Assessor you should not be involved with the care of trial patients since you must remain blinded to treatment allocations. The hours of work will depend on the number of patients to be recruited into the trial at your site, but is unlikely to exceed a few hours each week. The trial has a long-term follow-up of 10 years with assessments scheduled to take place shortly before surgery (pre-randomisation) and post-operatively at 3, 6 & 12 months and 3, 5 & 10 years. You receive training centrally from the Trial Manager. This page is designed to provide further training and support to you. The following guidance notes can be downloaded here.

Most hospitals have already recruited an assessor. Assessors' names can be viewed along with the other local ACTIVE team members on the Which hospitals? page.

What does an Independent Assessor do?

Please click on the bullet points below for guidance on what to do.

1. Organise trial patients’ visits to the clinic and carry out assessments at the proper time

1.1 Your local study co-ordinator will contact you each time a patient is entered into the trial to arrange with you the date of the patient’s pre-operative assessment and their contact details.

1.2. You contact the patient by telephone to arrange for him/her to visit you for the pre-randomisation assessment. The pre-randomisation assessment should coincide with the patients’ pre-operative assessment date if possible which you can find out from the study co-ordinator or from the Appointments Clerk. Once you have agreed a date, you send a confirmation letter to the patient, confirming the time, date, and place where you will meet.

1.3. Each trial patient should be assessed at the same time points as outlined in the trial schema. If patients experience complications requiring further intervention it may be necessary to do additional assessments. Over the course of 10 years it has been estimated that about half of the trial patients will need two extra assessments, in addition to those stated in the trial schema. The Trial Office will provide you with a timetable for the post-operative assessments but you can also look this up on the online database. Please aim to book patients in for assessment close to the scheduled dates (within 2 weeks of the date whenever possible).

2. Arrange for patients to claim travel expenses

2.1. Trial patients can only claim travel expenses for attending assessments that cannot coincide with routine visits to the hospital, i.e. the 6-month, 3-year, 5-year, and 10-year post-operative assessments, provided they present their travel details and any receipts to you or the Principal Investigator.

2.2. MRC funding will pay on the basis of reasonable actual expenditure incurred, up to £25 per visit, or in special circumstances more at the discretion of the Trial Manager. Please ask patients to complete the Travel Form which should be forwarded together with any receipts to the Trial Manager.

2.3. Remember, if possible, the first and third post-operative assessments should coincide with patients’ routine visits to the outpatients clinic (2/3 months and 1 year post-op). This is particularly important for patients who travel a long distance to the hospital.

3. Assess patients in accordance with the trial Protocol using a combination of semi-structured interview techniques, questionnaires and functional assessments (training will be provided)

3.1. The assessments you carry out will provide most of the data needed to determine the long-term effectiveness of Autologous Chondrocyte Transplantation (ACT) versus Standard Treatment for patients with isolated chondral defects of the knee. The trial is expected to influence the future treatment of such patients in the NHS, and world-wide. As Independent Assessor it is most important that you follow the protocol and maintain consistency since your contribution is vital to the success of the trial.

3.2. The pre-op Assessment Form and post-op Assessment Form are designed to enable you to document trial patients’ pre- and post-operative knee condition and knee-related quality of life. There are two sections to the Assessment Form. The first section includes notes and questions for conducting a semi-structured interview, with space for you to write up the interview, and the second section includes physical measures and an assessment plan of the patient’s functional performance. This Assessment Form will act as a guide and an aide memoir enabling you to:

a) Decide whether or not the patient has improved at the post-operative time points compared to their pre-operative state. By talking to the patient as well as assessing his/her knee symptoms and functional performance it should be possible to judge whether or not he/she has improved at each post-operative assessment by comparison to the pre-operative assessment.

b) Complete the Lysholm knee-score form. The Lysholm knee-score form requires you to judge the patient’s pain, instability, locking, swelling, limp, stair-climbing, squatting and need for support. You should therefore use the assessment to find out about these particular symptoms and activities. Base your Lysholm ratings on what you observe from the patient (rather than what the patient tells you) wherever possible. As well as getting you to ask questions, the Assessment Form includes examples of exercises such as stair climbing and squatting to test the patient.

3.4. Although we have suggested Physiotherapists should be recruited to work as Independent Assessors, the Assessment Form is designed to be comprehensible to non-Physiotherapists. If you are a Physiotherapist, please bear in mind that the style of this assessment may be different to how you would normally assess patients. You are not expected to advise the patient (patients will receive Physiotherapy separately) so try to ‘step back’ from your clinical job when assessing trial patients.

3.5. You should use the semi-structured interview to gain a holistic understanding of the person, so you can form a judgment of how their knee condition is impacting on their quality of life. Try to avoid focusing exclusively on specific symptoms and think about how the patient has been affected in their daily activities, work, leisure, family/social life, and mental health.

4. General Guidelines for Semi-Structured Interviewing

4.1. Allow enough time – although you are probably very busy, don’t squeeze assessments in if you haven’t enough time. Otherwise you will end up rushing the interview and putting the patient off giving honest and full answers to the questions.

4.2. Choose a setting which is relaxed and comfortable for the patient – if you have difficulty finding a quiet room, you might want to do the semi-structured interview in the canteen/restaurant over a cup of tea.

4.3. Be warm and friendly towards the patient - introduce yourself, remind him/her that you spoke on the phone, explain the purpose of the assessment and how long it is likely to take.

4.4.Use good interview skills – sit opposite the patient, have eye contact, show interest in what the patient is saying (smile, nod), maintain a relaxed, unhurried manner, speak slowly and clearly.

4.5. Focus on what information you want to get from the patient – use the questions in the Assessment Form as a guide but be prepared to change the order and format of the questions or add extra questions depending on what responses you get from the patient.

4.6. Listen carefully and think who’s doing most of the talking? – it should be the patient.

4.7. Keep the patient focused – more talkative patients may drift off the subject so you’ll need to remind them of what you are interested in talking about.

4.8. Recap on what the patient said – to clarify information, repeat back to the patient what you think they said.

4.9. Once the patient has provided you with enough information you must write up a summary of the interview using the headings on pages 3-4 of the Assessment Form. You should write the summary straight after the interview before you forget anything. Try to include some quotes from the patient (check with the patient if you can’t quite remember what he/she said). While you are writing the summary give the patient their questionnaire pack to fill in (see notes below).

5. Questionnaires

5.1. The three most important things to remember about the questionnaires are:
(a) Don’t forget to ask the patient to fill them in (while you are writing up the interview summary)
(b) Check the patient has completed them properly while he/she is still there (ask the patient to complete anything that is missing or unclear)
(c) Make sure the patient’s ID and the assessment date and number are clearly marked on the questionnaire pack.

5.2. The following questionnaires must be completed by the patient:

  • EuroQoL EQ-5D (at every assessment)
  • Patient Self-Assessed Lysholm Knee Score-Form (at every assessment)
  • Cincinnati Knee Rating (at every assessment)
  • IKDC Knee Form (at every assessment)
  • Resource Usage Questionnaire (at every follow-up assessment)

The questionnaires will be printed in a single Patient Pack in the above order.

5.3. Explain what the questionnaires are for and don’t minimise their importance - e.g. “The ACTIVE research study aims to find out how effective your knee treatment is over the next 10 years. To help us find out, it is important that you complete these questionnaires which are designed to measure your current general health, level of activity, and knee symptoms. One of the questionnaires is designed to explore the costs involved in having a knee cartilage defect.”

5.4. Explain to patients how they should complete the questionnaires – e.g. “Please read the questions and any instructions carefully. It is not a test so there are no right or wrong answers. If you are not sure how to answer anything, please re-read the question and give the answer which best describes what you think. You are the best person to answer the questions so please avoid asking anyone else for their opinion.”

5.5. Check the patient has completed all the questions properly. Don’t accept an incomplete questionnaire without first encouraging the patient to fill out unanswered questions – (see notes relating to each questionnaire below).

5.6. Most of the questionnaires have descriptive category choices for answers - check that patients haven’t put a mark in between the category choices or have written a description next to the question without ticking one answer. This problem is most likely to happen with the Cincinnati Knee Rating, the Lysholm Knee Score and the IKDC. If patients do this, please ask them to choose one answer which is the most representative of them. Where a patient is unable to give a single answer, this must be counted as missing data.

5.7. If the patient doesn’t understand a question, you can reread it for him/her, but do not rephrase the question or try to offer an explanation since this could lead to bias.

5.8. Don’t force patients to answer a question if they really don’t have an answer.

5.9. Always thank the patient for completing questionnaires.

5.10. The EuroQoL or EQ-5D is a general health measure which is quick to complete and is widely used for estimating cost-benefits of different treatments. It includes a visual analogue scale where patients are asked to draw a line pointing to their current health state ranging from 0 (worst imaginable health state) to 100 (best imaginable health state). The questions are rather limited/crude, e.g. the mobility question - try not to worry about this because the other questionnaires and your judgment will be used to give more precise measures of patients’ mobility.

5.11. With the Lysholm Knee Score-Form, Cincinnati Knee Rating, IKDC questionnaires patients may have difficulty committing themselves to one answer (see guidance note above).

5.12. Bear in mind that the Cincinnati Knee Rating and the IKDC were originally designed for sports people rather than our trial patients (who may be less ambitious about the level of sports they wish to do). The Cincinnati Knee Rating questionnaire begins with a Sports Activity Scale – check patients only tick one box for this.

5.13. The Resource Usage Questionnaire is designed to collect important information to be used for comparing the personal and public sector costs of ACI versus Standard Treatment. The following guidelines may help:

Q1 Visits to the hospital should include visits to any hospitals, not just your hospital.

Q2 If the patient can’t name or describe a surgical procedure they’ve had on their knee in the past 12 months, you could ask the Study Co-ordinator to find out from the patient’s notes (remember you must not look at the patient’s notes).

Q14 If the patient can’t remember what medication he/she has been prescribed for his/her knee during the last 12 months, you could arrange to phone the patient the next day to find out.

Q16 If patients are in paid employment / self-employed but currently on sick leave they should tick 1 or 2 but not 8.

5.14. At the pre-operative assessment you must give each patient a knee diary to take home (you will find one in the patient folder). The instructions to patients for completing the knee diary are written on the front page – please familiarise yourself with these instructions and explain them to the patient. Also draw patients’ attention to the back page which has a change of address form they can use if necessary. Tell patients that when this diary runs out they will be sent a new diary by post each year for the next 10 years.

6. Physical and Functional Assessment

6.1. Once you’ve finished writing a summary of the interview and have checked whether the patient has completed his/her questionnaires properly you can start the physical and functional assessment (Section 2 of the Assessment Form).
Page 1 of the Assessment Form gives instructions on what equipment to have ready and provides advice on how to maximise your blinding (see below for further advice on staying blinded).

6.2. Work through pages 5-10 of the Assessment Form, following the order in which the items appear on the pages. Always explain to the patient what you are doing and why.

6.3. Item 2 – when asking patients to point out where they get pain in their knee (using the knee charts on Pages 6-7) remember to also ask the patient to point out any other painful areas of their body and document these using the body chart on page 8.

6.4. List the painful areas in the tables below the charts in order of magnitude, writing a description (whether pain is intermittent, constant, or constant variable), and noting any aggravating factors and easing factors. If you find it helpful to ask patients to rate their level of pain on a 0-10 scale, ask them to use the Borg rating scale on Page 9, ensuring they refer to the description of pain and the corresponding number.

6.5. At all follow-up assessments make sure the patient wears tubi-grip over both knees, ensuring you don’t see his/her scar.

6.6. Item 4 (Page 5) – when the patient is wearing tubi-grip it may be difficult to assess swelling, but it should still be possible to feel for swelling and compare the two knees. If grading is difficult, please write a description of what swelling (if any) you have noticed. You must not remove the tubi-grip. Grade the effusion using the sweep test:

Grade 1 = Trace/ Minor; Grade 2 = Moderate; Grade 3 = Large.

6.7. Item 5 – whether you decide to measure knee flexion and extension with patient sitting, lying on back (supine) or lying on front (prone), remember to be consistent and stick to the same position on subsequent assessments. You will receive training on how to do these measurements with the goniometer if necessary.

6.8. Item 6 - you can use the Oxford grading system to grade muscle strength of quads and hamstrings. The patient should be sitting with feet above the ground while you test muscle strength. Grade muscle strength as follows:
0 = No contraction
1 = Flicker of a contraction
2 = Active movement with gravity eliminated
3 = Active movement against gravity
4 = Active movement against resistance
5 = Full functional strength
If both legs score 5 but one is weaker than the other please document this.

6.9. For “Pain during Exertion” (Page 9) you may want to use a treadmill (if available). Before doing this test, let the patient know they can stop at any time if heir level of pain or discomfort gets too much or if they are concerned about hurting themselves. If the patient does stop before 4 minutes of exercise, record the time, as well as their pain rating.

6.10. Page 10 includes examples of how you might test patients’ functional performance. You will want to see patients stepping up & down, and squatting so that you can complete the related questions on your independently assessed Lysholm Knee Score-Form. Patients should not be asked to skip, hop or jog until at least 6 months follow-up, and only then if the patient is happy to do so according to his/her own stage of rehabilitation.

7. Independently assessed Lysholm Knee Score-Form

7.1. By this stage your thorough assessment of the patient should enable you to complete the independently assessed Lysholm Knee Score-Form. It is most important that you remember to complete this.

8. Cessation of Benefit Assessment Form

8.1. At all post-operative assessments it is most important that you complete the Cessation of Benefit Assessment Form. “Cessation of benefit” is the time when patients are thought to no longer benefit from their surgery. However, with some of the treatments, patients may only feel the benefit after a lengthy period of rehabilitation (sometimes more than 1 year). Please state when a patient hasn’t improved even if you expect that patient to benefit in the longer term. We will then now how long the rehabilitation period takes for different treatments.

8.2. Cessation of benefit will be analysed by a statistician at 1, 3, 5 & 10 years post-operatively using the information collected from you and the patient.

8.3. Patients are judged to have ceased benefiting if they meet at least two of these three criteria:
1. A significant decrease in the patient-rated Lysholm score
2. A significant decrease in the independently-rated Lysholm score
3. Your judgment that the patient has not improved.

9. Try to remain blinded from patients’ allocated treatments

9.1. You are the only member of the local research team who is blinded to patients’ treatment allocations and it is very important that you avoid becoming ‘unblinded’. If you know what type of treatment a patient had, this can introduce bias into your outcome assessments, e.g. if you form an opinion on what type of treatment is working better, and know which patients had that treatment, you may unwittingly score those patients better.

9.2. It is very easy in a busy clinic or ward to overhear staff discussing patients’ treatments, or to access patients’ notes. Therefore, to maximise blinding, you will not be involved in the treatment of trial patients and will, if possible, not visit any clinics or wards when the trial patients are there.

9.3. Ideally, you will assess patients in a separate part of the hospital, although part of the assessment may involve using the physiotherapy gym. The Study Co-ordinator will be particularly careful not to discuss the trial patients’ treatment with you, or say anything which could give a clue to which treatment the patient had.

10. Accurately input data using the active trial database

10.1. You will be advised on how to enter the information into the ACTIVE database which is available online. As a backup please send a copy of the questionnaires and forms to the ACTIVE trial office. You do not need to send copies of your Assessment Form since this information will only serve as your aide memoir but you must send copies of all the patient questionnaires, the Cessation of Benefit Form, and your independently assessed Lysholm Form. Ensure that your own original copies are filed securely as they will need to be kept for at least 10 years.

11. Liaise with other members of the research team as necessary to assist in the smooth running of the trial

11.1. The Study Co-ordinator will liaise with you to ensure you book patients for their pre-randomisation assessment on an appropriate date, within 3 months prior to surgery, coinciding whenever possible with the patient’s pre-operative clinic appointment. The Study Co-ordinator may also arrange the occasional meeting for you and others involved in the study to attend. A meeting will be particularly important at the start to make sure everyone is aware of how the trial will run.


12. Due Assessments

The Trial Office will send you a reminder e-mail at least 4 weeks before an assessment is due thus allowing you adequate time to contact the patient and make an appointment.

Assessment Timelines
Assessments need to be conducted and data collected as close to the scheduled timescales as possible. However, the database will accept data collected early or late within the following timescales:

2/3 mth assessment: 8 - 16 weeks inclusive

6 mth assessment: 21 - 34 weeks inclusive

12mth assessment: 43 – 64 weeks inclusive

Do not conduct assessments or collect data outside of these time points (unless the patient returns with complications and requires an additional assessment) as the data cannot be counted.

Please inform the Trial Office if an assessment has been missed, as the database has to be amended accordingly.

13. Missed Assessments

A small minority of patients may not turn up for assessments – if a patient regularly cancels/DNA appointments please make a further appointment (within the timescales above). Post out the questionnaire pack prior to this new appointment with a pre-paid envelope so that the patient can at least provide this data, even if they fail to attend the appointment. Please contact the Trial Office if you need help organising postal questionnaires. Remember the questionnaires also have to be completed within the above timescales.


14. Contact the central Trial Manager with any problems

12.1. Please contact the Trial Manager, Dr Johanna Wales, by email/telephone (tel: 01691 404142) to discuss any problems with assessments or issues relating to the trial.

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ACTIVE is being carried out by the Robert Jones & Agnes Hunt Orthopaedic & District Hospital NHS Trust in collaboration with the University of Birmingham Clinical Trials Unit and Health Economics Facility. The trial is funded by the Medical Research Council and administrated by Keele University.