**9. Resources**

**6. Develop informed consent form**

32 Clinical Trials in Vulnerable Populations

consent must be kept in the investigator's file [19].

**7. Ethical approval**

pertinent regulations [21].

**8. Quality of data**

Consenting is the process by which participant voluntary confirms his/her willingness to participate in the trial. The medical researchers should be careful and pay special attention when obtaining consent from vulnerable subjects, including children, the elderly, and psychiatric patients. Subjects with low perception may feel unable to make use of their right to judge the profits or hazards of the intervention and decide whether to consent or not. Child and adolescent psychiatrists should be careful about the decisional capacities of children and the role of the parents in medical decision making. Hence, obtaining informed consent form from the legal guardian of the subjects under legal age and the patients with severe psychiatric disorder is crucial. In addition, obtaining oral ascents from the subjects with low perception or children who will participate in the medical research is essential. Full procedures, rights and responsibilities, potential hazards, and benefits should be described to each participant and the legal guardian. Then, informed consent must be dated and signed by the legal guardian before the subject participates into the trial. Then, a copy of informed consent form and related information should be delivered to the parents or guardian. The original informed

The researcher should submit the sponsor-provided protocol document to the Institutional Review Board (IRB) or Research Ethics Board (REB) for approval before recruiting any case into the trial. The investigator should also submit consent forms and assessment tools, including questionnaires. During specific intervals, the researcher must report the progress of the trial and request re-approval of the research by the IRB/REB. The IRB/REB will ask for a summary of trial progress [20]. The responsibility of the ethics committee is to guarantee the protection of the rights and well-being of human subjects enrolling into clinical trials. The ethics board decisions are in line with the latest revision of the declaration of Helsinki and local

Every research study needs to have a written protocol which includes the plan of the study as detailed as possible. The design and method of the trial should be well-thought-out, and the protocol must be well-written and approved by a faculty council. Protocol includes the trial information in detail and should consist of the trial title, the name of the main investigator, supervisor/s and sponsor/s, literature review, materials and methods, characteristics of intervention, dosage, duration, randomization, blinding, allocation concealment, inclusion criteria, exclusion criteria, project schedule (Gantt chart), and budget of the project [22].

In trials performing on children and adolescents, the investigators should be trained and interested in the scientific aspect and ensure that the study meets the needs of patient's health. One of the requirements of good clinical practice is that the researcher has adequate access to resources to carry out a sound clinical trial. Resources include not only sufficient budget and materials, but also the ability to recruit adequate numbers of research subjects. Furthermore, the research team members must have adequate information about their specific roles, and they should have adequate time to deal with subjects and conduct the trial. In trials being conducted in children and adolescents, at least one of the team members should be specialized or trained previously to deal with the subject on this age span [24].
