First, the clinic will arrange with you a screening appointment, and tell you what to avoid in the days prior to the screening. This will usually include alcohol, recreational drugs, most or all medications, and any food or beverages containing caffeine, such as tea, coffee, cola, cocoa, and chocolate. They may also tell you to refrain from strenuous exercise, and not to eat or drink certain things. Some clinics also ask you to fast (not eat) for between 4 and 12 hours before a screening. When you arrive at the clinic, you usually need to show photo ID, and then you are given forms to fill out concerning your personal details and your medical history.
You will need to sign a consent form for screening, which gives the clinic permission to test your blood for HIV and Hepatitis B & C, and to test your urine for drugs and alcohol. The results of these tests are confidential unless the clinic tells you otherwise. The most important form you will encounter is the legally required “informed consent form”, which you must read to ensure that you are familiar with what the study involves, and any possible risks it might entail. If the study involves a drug, it will explain the type of drug, its purpose, its stage of development, and its reported or possible side effects in humans. Most of the common side effects will be minor, and typically include such things as headache, sleepiness etc., which often can be attributed to other causes.
The ICF will also include other information, such as the name and contact number of the doctor or doctors in charge of the study, and a phone number to call if you feel your rights have been violated, or your safety compromised. This will refer to a Research Ethics Committee (called an Institutional Review Board ), which consists of persons of medical, legal, and ethical standing whose responsibility is to approve or reject the human research studies proposed to them from clinics in the local area. These committees do not approve studies they consider to be dangerous. The form will also explain what happens in the unlikely event that an injury occurs due to participation in a study. British clinics and their sponsors are required to carry insurance providing compensation to volunteers for any harm or injury they might suffer, and the amount is awarded according to national guidelines. In the US, you might find it necessary to pursue a claim for additional compensation through legal channels. In any event, medical treatment will be provided for volunteers who lack health insurance. After you have read the entire form carefully, you will then be asked to sign the form. In doing so, you are stating that you understand the possible risks involved and agree to take part of your own free will.
You are entitled to ask the doctor any questions you may have about the study, and they are obligated to explain it to you. After you sign the ICF, you will be given your own copy to keep. Following this, you will, in no particular order, have blood and urine samples collected, vital signs taken (blood pressure, pulse, temperature), height and weight recorded, and be interviewed regarding your medical history and current state of health. You may also have an ECG (electrocardiogram) which involves leads attached to patches placed on your chest (and sometimes arms and legs) and connected to a machine which records the electrical activity of your heart. You may also have a chest X-ray for some studies, and possible hearing, vision, or psychological tests.
Following these, you will then undergo a physical exam by a doctor on staff who will determine if you are presently healthy. After the screening, you may be given a time to phone the clinic to learn if you passed the screening, and whether you have been accepted onto the study. At some point you will be provided a schedule of the study dates. If any tests appear outside the normal range but are close, you may be asked to return in order to have them repeated. Some clinics will pay you for screening (around $10-50 /£10-50), or reimburse your expenses in getting there, but this is not very common.