I'm Designing My Study

Study Population

We want to make sure you are set up for success with a feasible and large enough recruitment pool. This document may help you think through your study sample, sampling method, and sample size. GME Research Staff can support you in determining how to power your study appropriately. Further background on statistical methods can be found in: this list of common statistical terms, this course on avoiding statistical errors, and this refresher article on basic statistical concepts

Carefully describing your study population through inclusion and exclusion criteria increases the chances that your results will be reliable and reproducible. 

  • What are the characteristics of participants needed for your study? Consider the variables you wish to include in your study. It may help to think through inclusion criteria first; inclusion criteria may be thought of as a potential subject’s ticket through the door for consideration in your study (common factors: age, gender, stage of disease, etc). Next, think through any factors that would disqualify participants from being a good fit for your study (e.g. comorbidities, current medications etc.).
  • GME Research Staff will guide you through the process of obtaining specific EMR or data registry data.

You may want to use already collected data for your study (e.g. from the EMR at CMH). Alternatively, you may need to go straight to the source – the participants themselves – and recruit subjects. GME Research Staff can connect you with CMH data on your proposed study population and support you through this decision.

If you are worried that your sample will be too small, consider: 

  • Broadening the variable categories you have applied to your study population (such as a wider age range)
  • Determining whether you can remove an exclusion criterion or comorbidity to analyze separately while still maintaining the integrity of the research question, scope of the project, and the scientific value
  • Expanding the study population to nearby hospitals through a proxy IRB process
  • Utilizing data from national databases


If you do not have access to the study population, you need to figure out who will collaborate with you on your study idea. Consider what would be required of that potential collaborator and what they would get from collaboration. In line with the level of involvement, research team members should be listed as co-investigators.

Conceptually, your recruitment plan will need to be non-coercive, voluntary, and respectful. 

Logistically, think through: when, where, and how you will approach potential participants. Consider if your recruitment site location is appropriate – both in terms of logistics as well as whether or not the potential participant would have enough time and capacity to participate.  

To make sure that participants have all the information they need to decide whether or not to participate, make sure that the approach occurs in an appropriate setting: consider where potential participants are at the time that they might consent to participate in your study. Do patients have the medical decision making capacity to process the opportunity fully and provide fully informed consent? 

    • Ex: it would not be appropriate to attempt to recruit or consent a patient if they were in acute and overwhelming pain or impaired. 

The IRB must approve all recruitment materials, such as scripts, emails, or printed/electronic materials used to recruit participants.

    • Pro Tip: be sure to use plain and clear language when communicating with a potential participant during the recruitment and consenting process. A great resource can be this glossary that allows you to look up lay language for medical terms. 
    • Pro Tip: upon IRB approval, the Research Department can assist you in translating your study documents into other languages. For translation assistance, please consult All Languages Interpreting and Translating, Inc.
      • Phone (805) 654-0509 | Facsimile (805) 293-8524 
      • Email language@translateventura.com

Consider whether the time burden is reasonable for a potential participant and whether you will offer compensation. If you plan to offer compensation, it should be proportionate to the commitment, and you will need approval from the ADGME for study funding.

Consider the following:

  • Whether you will need to put a flyer on the wall in a common space, such as a clinic (which would also require permission of the clinic director), or if a recruiter needs to present the study to the patient. 
  • Whether you need to translate your forms into additional languages. (Reminder: GME Research Staff and IRB must approve all written recruitment materials, including flyers/emails, etc.

The FDA considers study advertisements to be the beginning of the informed consent process. The IRB will make sure you get it right from the get go. Required information for study advertisements includes:

  • Name and address of investigator/ research facility; 
  • Purpose of the study; 
  • Summarized inclusion/exclusion criteria; 
  • List of any procedures involved;
  • Time (or other) commitment required; 
  • Location of research;
  • Who to contact for further information.

Yes, but you must consider the following:

All research study team members must be listed on the IRB application. Before recruiting team members, consider whether they have time to be trained in obtaining informed consent for research participation and if they have time in their workflow to recruit and/or consent participants. 

When asking for assistance with recruiting, remember that people are giving of their limited time and doing you a favor. In line with their level of involvement, research team members should be listed as investigators, names on presentation, etc. (You can always refer to the CMH Authorship Policy as a guide on who to include, how to determine authorship order, and responsibilities.) 

Review the study population to consider whether recruiters must speak languages other than English.

If others assist you with recruiting, determine how you will be alerted if an eligible patient needs to be approached. 

    • Who needs to know about your study and what do they need to know to be able to tell if a patient would be a good fit? 
    • Where will you keep recruitment materials? 
    • How will you and your Research Study Team access them when needed?  Remember, study data must be protected at all times. 

If others assist you with consenting, determine where you will keep blank Informed Consent materials and how consenters will access them when needed. Likewise, come up with a plan for where you will store signed forms. 

    • Will this need to be electronic or printed? 
    • How will any paper study documents be securely protected? 
    • What will others need access to? 
    • How will they know where they are kept and how to access them?


Almost all studies require informed consent.  There are very few times when obtaining informed consent is not feasible for a study that is of minimal risk; this usually applies to anonymous surveys, de-identified surveys, and retrospective analysis that also utilizes the de-identification process. The necessary documents can be found on the CMH Institutional Review Board website on the intranet.

You will need to complete a Waiver of Authorization or an Alteration of the Authorization if all five of the following criteria are met:

    • The research involves no more than minimal risk to the subjects, AND
    • The research could not practicably be carried out without the waiver or alteration, AND
    • If the research involves using identifiable private information or identifiable biospecimens, the research could not practicably be carried out without using such information or biospecimens in an identifiable format, AND
    • The waiver or alteration will not adversely affect the rights and welfare of the subjects, AND
    • (Whenever appropriate) Subjects will be provided with additional pertinent information after participation.
    • Please note:
      • If your research requires PHI, then you must also complete a Waiver of HIPAA Authorization.
      • If consent for your research will be obtained verbally, you must also complete a Waiver of Documentation (Signature) of Informed Consent.

If you are conducting a case report and the patient is deceased, you will seek the consent of the patient’s Legally Authorized Representative. 

There are limited times when a Waiver or Alteration of HIPAA Authorization may also be appropriate. To apply, all 3 criteria below must be met:

    1. The use or disclosure of protected health information (PHI) involves not more than minimal risk to the privacy of individuals based on:
      • An adequate plan to protect the identifiers from improper use and disclosure; 
      • An adequate plan to destroy the identifiers at the earliest opportunity consistent with conduct of the research, unless there is a health or research justification for retaining the identifiers, or such retention is otherwise required by law; 
      • Adequate written assurances that the PHI will not be reused or disclosed to any other person or entity, except as required by law, for authorized oversight of the research project, or for other research which the use or disclosure of PHI would be permitted by the Privacy Rule.
    2. The research could not be practicably conducted without the waiver or alteration, AND
    3. The research could not be practicably conducted without access to and use of the protected health information.   

Remember, when applying for a waiver of documentation of consent, you must complete a waiver or alteration of HIPAA Authorization. 

CMH adds bar codes to research consent forms so that they can be electronically placed in a patient’s file. In order to receive your study’s individualized bar code, you need to ensure that the IRB study number/ consent form version date is formatted onto each page of the consent form submitted to the IRB. You will then receive your consent form with the barcode in a PDF format. 

*Do not distribute consent forms to patients until you have received the PDF with barcodes.* 

  • Pro Tip: print the form instead of copying it multiple times, which reduces the barcode quality. Ensure that the IRB study number/consent form version date is formatted onto each page of the consent form submitted to the IRB.

There are limited times when it is not feasible to obtain signed documentation of informed consent for minimal risk research. You may obtain informed consent if you explain all important aspects of the study and allow time for the potential participant to ask questions. After the explanation, you can provide the potential participant with written information about the study (this can be a written consent form or a study information sheet), give them time to make a decision, and answer any follow-up questions. At this point, the participant can verbally agree to participate.

Verbal consenting may be preferable to written consent for online or mailed surveys, telephone interviews, or when anonymous sensitive information is collected and there is a desire not to have written documentation that links the participant to the research study.

To verbally consent patients, you need to complete a Waiver of Documentation (signature) of Informed Consent. The necessary documents can be found on the CMH Institutional Review Board website on the intranet.

You may apply for a Waiver of Documentation of Informed Consent if ONE of the following criteria is met:

      • The only record linking the subject and the research would be the consent document and the principal risk would be any harm from a breach of confidentiality. (Each subject would be asked whether they want documentation linking them with the research). OR
      • The research presents no more than minimal risk of harm to subjects and involves no procedures for which written consent is normally required outside the consent OR
      • The subjects or legally authorized representatives are members of a cultural group or community in which signing forms is not the norm, the research presents no more than minimal risk of harm to subjects, and there is an appropriate alternative mechanism for documenting that informed consent was obtained.

Remember, when applying for a waiver of documentation of consent, you must also request a Waiver or alteration of HIPAA Authorization. 

  • Pro Tip: be sure to use plain and clear language when communicating with a potential participant during the recruitment and consenting process. This glossary offers a great resource to look up lay language for medical terms. 

If there is not a requirement to track how many people decline to participate (and why they declined), it can still be helpful for both integrating lessons learned for your future studies and for describing your process in a resulting manuscript. If you decide to track declinations, be sure to specify a process that is shared with each Research Study Team member who is recruiting and consenting. This process may include creating a document that is shared among Research Study Team members or crafting a process for members to track individually and combine records at the end of enrollment.

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