Normal Values of Ambulatory 24-hour Oesophageal pH-impedance Monitoring in an Indian Cohort of Participants
Conditions: GERD (Gastroesophageal Reflux Disease)
Sponsor: Asian Institute of Gastroenterology, India

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INFORMED CONSENT DOCUMENT (ICD) 
[Written subject information sheet & consent form] 
 
Study Title: 
Normal values of ambulatory 24-hour oesophageal pH-
impedance monitoring in an Indian cohort of health 
volunteers 
Language: 
English 
 
 
Subject Identification 
Subject full name in BLOCK LETTERS:  
 
Subject identification (ID) No:                        Date of Birth / Age at the time of consent:  
 
 
Study Doctor 
Name of the Investigator(s):  
 
Email ID:  
Dr. Krithi Krishna Koduri 
drkrithivk@gmail.com 
Name of the sub-investigator(s) / Guide: 
Email ID: 
Dr. Aniruddha Pratap Singh 
draniruddhapratapsingh@gmail.com  
Dr. Rakesh Garlapati 
 
 
 
Address(s) of the study site: 
AIG Hospitals, No 136, Plot No 2/3/4/5 Survey, 1, Mindspace Rd, Gachibowli, Hyderabad, 
Telangana 500032. 
Telephone: 040 4244 4222 
 
 
 

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1) Participation. 
We are approaching you with a request to participate in this study as you are a healthy 
individual without any gastrointestinal symptoms, and we are seeking to establish normal 
values for acid exposure time through ambulatory 24-hour pH-impedance monitoring. Before 
you take part in this study, it is important that you understand what the study involves. Please 
read this information carefully and ask any questions that you might have. You will be 
included in the study only after you give consent to take part in the study. 
 
2) Purpose and Aim of the Study. 
The aim of this prospective study is to establish the normal Acid exposure times and 24-hour-
ambulatory pH values in healthy Indian volunteers. 
 
3) The approximate number of participants and the expected duration of your 
participation in the study:  
There will be 50 healthy volunteers in this study. Your participation will last for a 24-hour 
period. 
 
4) What other treatment options do I have? 
Since this study is observational, there are no alternative treatments being tested.  
 
5) Study Procedure / Methodology. 
Participants will first go through a general health check-up, which includes a physical exam 
and lab tests. These tests will check things like their blood count, liver and kidney function, 
blood sugar levels, and thyroid health. If they agree, they may also have an endoscopy, 
which is a procedure where a doctor looks inside the stomach using a flexible tube. The 
doctor will also ask about any food allergies, heartburn (a burning feeling in the chest), or 
other digestive issues. They will also gather information about the person's daily habits, 
such as their eating patterns, sleep, and exercise routines. 
After fasting for 8 hours (not eating or drinking), all participants will undergo a test called 
HRM (High-Resolution Manometry), which checks how well the muscles in the esophagus 
(the tube that carries food from the mouth to the stomach) are working. Participants will lie 
down on their back during the test. A small tube (called a catheter) will be placed in their 
throat, and after getting used to it, they will be asked not to swallow for 30 seconds. This 
will allow the doctors to measure how the muscles are at rest. Then, they will swallow small 
amounts of water (5 mL) every 30 seconds followed by 10 swallows of 5 mL every 30 
seconds to acquire dynamic parameters. so doctors can measure how the muscles work 
when swallowing. The HRM system uses a special catheter with many sensors that measure 
pressure in the esophagus from the throat all the way to the lower part of the esophagus 
(near the stomach).  
Another test will measure how food and liquids move through the esophagus and if there’s 
any acid, which can be important for checking for acid reflux (when stomach acid comes 

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back up into the esophagus). For this test, a small probe (tube) with sensors will be placed 
in the nose and passed into the esophagus. The probe has special electrodes that measure 
electrical signals to check for acid levels and the movement of food. The electrodes are 
placed at different points above the lower part of the esophagus to track the movement and 
acid levels in the area. Before starting, the electrodes will be tested and adjusted to ensure 
they are accurate. 
The combined test will last for 24 hours. During this time, participants can continue with 
their usual daily activities, like eating, sleeping, and exercising. They will also be asked to 
record any symptoms they experience, such as heartburn, burping, or stomach upset, and 
press a button on a small device to mark when they eat, change positions, or feel any 
symptoms. This will help the doctors track how the body is reacting during normal daily 
life.  
The procedure is non-invasive and aimed at understanding the normal reflux patterns in 
healthy individuals. 
 
6) Role of the Patient:  
Your role in this study is to allow for the placement of the pH-impedance monitoring probe 
and to carry out your daily activities During this time, you’ll need to note any symptoms you 
might have (if any) and follow the instructions provided by the study staff. 
 
7) Follow-up / Duration of the study. 
The study requires one-time participation over 24 hours, and you will be required to attend 
the study site for the initial screening, probe placement, and data collection. There is no 
follow-up required after the study is completed. 
 
 
 
8) What are the possible risks (adverse effects/advents events) and discomforts to you? 
The procedure is generally safe; however, potential risks include minor discomfort from the 
placement of the nasal probe or irritation 
 
9) What are the expected benefits of this study?  
You may or may not benefit from participating in this study, but the knowledge gained may 
benefit others. 
 
10) Adverse events and compensation. 
 You may experience discomfort from the probe in your nose, throat, or oesophagus. 
 
11) Your responsibilities 
Completely read the consent form and ask the Principal Investigator (PI) any questions you 
may have. You should understand what will happen to you during the study before you 
agree to participate. You should talk to the Principal Investigator (PI; the person in charge 
of the study) if you want to stop being part of the research study. You should report to the 
PI immediately about any problems you may be having with the study procedure/device. 

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You should fulfill the responsibilities of participation as described on the consent forms 
unless you are stopping your participation in the study. You can ask for the results of the 
study, if you want them. You should keep a copy of the consent form for your records 
 
 
12) Voluntary Participation / Withdrawal from the Study 
Your participation in this study is entirely voluntary. It is up to you to decide whether to 
take part or not. Even if you do decide to take part, you are free to leave the study at any 
time without giving a reason. This will not affect your future medical care in any way. 
Furthermore, your study doctor may withdraw you from the study if he/she feels this is in 
your best interest, or in case of stopping the study early. If you decide to withdraw your 
consent to participate in the study, your study doctor will ask your permission to perform 
the final evaluation and to collect the data through a report form. If you do not agree, no 
new data on you will be added to the database. 
Your doctor, the sponsor of the study or designee, may end your participation in this study 
at any time without your consent.  The possible reasons for ending your participation: if the 
study treatment offers you little or no future benefits or if you develop severe or life-
threatening side effects. You will be discontinued from the study if you fail to follow 
directions for participating in the study. 
 
13) Permission for Review of Records, Confidentiality and Access to Records 
After seeking permission from you, the study doctor or research staff will collect 
information about you. This information called data will be entered without your name, on 
a report form. In all these report forms a code will replace your name. All the data collected 
will be kept confidential. Authorized personnel will enter the data into the investigator’s / 
sponsor’s case report form or computer database. The data collected will be used for the 
evaluation of the study and may be used in the future in related or other studies. This data 
may also be used for the purpose of publication and presentations at Scientific platforms.  
 
The data may be submitted to health authorities for registration purposes. Health authorities, 
Indian Council of Medical Research (ICMR) and like, Institutional Ethics Committee (IEC) 
/ Institutional Review Board (IRB) or other persons required by law may review the data 
provided.  
 
To make sure that the data collected from you is correct, it is necessary for the sponsor or 
national / international authorities to directly compare them with your medical record. Such 
checks will only be done by qualified and authorized personnel. While all reasonable efforts 
will be made to keep the data confidential, absolute confidentiality cannot be guaranteed.  
 
14)  Questions/Information. 
 
(i) If you or your representative(s) have any questions regarding the study or in case of     
study related injuries, you should contact your study doctor. 
 
Name of the investigator/study doctor: Dr. Krithi Krishna koduri 
Telephone: +91 9182645727 
 
 

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(ii) If you or your representative(s) have any questions regarding your subject rights as they 
relate to the study, you should contact the following personnel as allowed by local regulation 
and IRB/IEC policy,  
 
       Name of the IEC Personnel: Dr. Deepa Shukla 
  Telephone: +91 9953900117 
 
(iii) If you seek emergency care, or if hospitalization is required, please inform the treating 
doctor that you are participating in a clinical trial. 
(iv) If any new information becomes available during the study that may affect your 
willingness to participate, you will be informed. 
 
Informed Consent Declaration 
 
Date: _____________ 
Subject Name: ______________________________________________ Sex: __________ 
S/o, W/o., D/o: _____________________________________________________________ 
Subject ID: _______________________________________________________________ 
Date of birth/Age at the time of consent: _______________________________________ 
Address of the subject: _______________________________________________________ 
___________________________________________________________________________ 
Subject contact number:______________________________________________________ 
Qualification: _____________________________________________________________ 
Occupation: Student / Self-employed / Service / Housewife / Other (Tick as appropriate) 
If other, kindly mention: _____________________ 
 
● I have been provided with the details of the known or foreseeable side effects and risks of the 
research medication and study procedures that I may receive. 
 
● I understand I am free to accept or refuse my participation at any time without giving a reason. 
My decision to accept or refuse my participation will have no effect on my continuing treatment. 
I understand that I am free to discontinue my participation at any time without giving a reason. 
My decision to discontinue my participation will have no effect on my continuing treatment. I 
will keep all my rights to treatment and alternative therapy.  
 
● I agree that data collected for the study will be used for the purpose described above, including 
transferring data to the case report form or database and processing and archiving by AIG in a 
coded form with respect to the confidentiality of my data. 
 

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● I agree that direct access to my medical records may be given to authorized persons representing 
national and international authorities. These authorities may include the local regulatory 
authorities or Institutional Ethics Committee (IEC)/Institutional Review Boards (IRB’s). 
 
● I understand that my study records can be forwarded to my primary physician if I request my 
study doctor to do so. 
 
● I will not lose any rights that I have under the law by signing and dating this form. 
 
● I have read and understood the information presented in this informed consent form. I have been 
given the opportunity to ask questions, and they have been answered. 
 
● I will receive a signed and dated copy of this Informed Consent Form.  
 
 
Serial 
No. 
Particulars 
Initial in 
box 
1. 
I confirm that I have read and understood the information sheet dated 
__________ (dd/mm/yyyy) for the above study and had the opportunity 
to ask questions. My questions have been answered satisfactorily. 
 
2. 
I understand that my participation in the study is voluntary and that I am 
free to withdraw at any time, without giving any reason, without my 
medical care or legal rights being affected.  
 
3. 
I understand that the ethics committee and the regulatory authorities will 
not need any permission to look at my health records both in respect of 
the present study or any further research that may be conducted in 
relation to it even if I withdraw from the trial. I agree with this access. 
However, I understand that my identity will not be revealed in any 
information released to third parties or published. 
 
4. 
I agree not to restrict the use of any data or result that arises from this 
study provided such use is only for the scientific purpose(s). 
 
5. 
I agree to take part in the above study, allow access to my data in the 
study, and I agree to co-operate and inform unexpected or unusual 
symptoms experienced during the study. For the duration of the study, I 
will notify the investigator of any other medical treatments that may be 
necessary to undergo. I received a copy of this consent form. 
 
6. 
All the above has been explained to me in a language I know and I 
understand. 
 
 
 
 
 
 
 

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____________________              _____________________                 _________________ 
  Name of the subject                 Signature /thumb impression               Date (DD/MM/YYYY)   
                                                                 of the subject 
 
_____________________           ___________________                     __________________      
 Name of the legally                  Signature/thumb impression                 Date (DD/MM/YYYY) 
acceptable representative       of the legally acceptable representative 
(Mention relationship with 
 the subject) 
 
 
________________________            ______________________         ________________ 
   Name of the investigator               Signature of the investigator          Date (DD/MM/YYYY)          
      
If the subject / legally acceptable representative cannot read: 
 
 
 
__________________________      _____________________                  ______________   
Name of impartial witness 1           Signature of the impartial               Date (DD/MM/YYYY) 
                                                         witness 1              
 
 
 
___________________________         ___________________                    ______________    
    Name of impartial witness 2           Signature of the impartial           Date (DD/MM/YYYY) 
                                                              witness 2                          
        
 
Nominee(s):  
 
Name: ____________________________________________________________________ 
 
Address___________________________________________________________________  
 
Telephone if any: ___________________________________________________________ 
 
 
Legally accepted representative (LAR) [in case of signature obtained from LAR]: 
 
Name: ____________________________________________________________________ 
 
Address___________________________________________________________________  

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Telephone if any: ___________________________________________________________ 
 
 
Impartial witness(es) if any: 
 
Name: ____________________________________________________________________ 
 
Address___________________________________________________________________  
 
Telephone if any: ___________________________________________________________