Incidental findings in research are "observations of potential clinical significance unexpectedly discovered in healthy subjects or in patients...and unrelated to the purpose or variables of the study."¹

Although incidental findings may occur in various types of studies, they are likely to occur in imaging research due to the nature of imaging and the increasingly high resolution of imaging tools.

In 2005, NINDS, NIDA, NIBIB, NIMH, NIA and Stanford University sponsored a meeting on "Detection and Disclosure of Incidental Findings in Neuroimaging Research."²

The report from the meeting titled "Detection and Disclosure of Incidental Findings in Neuroimaging Research²" indicated that a significant percentage of neuroimaging studies reveal incidental findings:

"Variations from expected brain morphology have been reported to occur in as many as 20% of research participants with clinically significant findings occurring in 2-8% of children and adults."

The report generated a number of recommendations, one of which was:

"In neuroimaging research, scientists and clinicians should anticipate the potential for incidental findings in experimental design and establish a process to handle the discovery of an incidental finding.²"

A report from the 2005 NIMH Council Workgroup on MRI Research Practices³ recommended that "...standard procedures should...be in place for the detection and reporting of incidental findings" including an informed consent process that:

• Differentiates between scans performed for research versus clinical activities
• Describes the likelihood of incidental findings that may lead to potential harms or adverse consequences or the possibility of incidental findings with uncertain clinical significance and associated risks
• Discloses whether qualified individuals are available to evaluate scans
• Describes an established policy of protocol for managing incidental findings

This document presents issues related to the disclosure of incidental findings and points to consider for investigators who are planning imaging studies.

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Issues Related to Disclosure of Incidental Findings

Obligations of Investigators

Immediate Clinical Significance:

The obligation of investigators to disclose incidental findings to research participants requires specific consideration.^1, 4  While the interests of participants may be furthered through disclosure of findings with immediate clinical significance (e.g., tumors, aneurysms, broken bones, or blood clots), there are risks associated with the communication of false positives or findings that are merely "suspicious."¹ A thoughtful informed consent process is one critical aspect of investigator obligations. Investigators should be committed to the formation of a trusting relationship with research participants. Consideration, therefore, should be given to individual privacy, confidentiality of data, cultural norms, and plans and options for disclosure of incidental findings.

Unclear Clinical Significance:

Obligations related to the possibility of, and follow-up process for, incidental findings whose clinical significance is unclear should be balanced against the importance of maximizing the autonomy of research participants. Illes et al.¹ recognizes that research participants have a "right not to know" about incidental findings and indicate that investigators have obligations to present this option to prospective participants and respect participants' preferences whenever possible.

Incidental findings may have unclear clinical significance due to:

• Lack of consensus among clinical experts about the clinical relevance of structural abnormalities
• Early stage of technology where it is unclear as to whether the imaging technique can reliably identify an abnormality
• Absence of clinical expertise among research staff such that abnormalities would not be recognized or confirmed as such

Consequences of Disclosure:

In addition to a consideration of obligations, it is equally important to consider both the resources available to research institutions, as well as the short-and long-term consequences of disclosing incidental findings to research participants. Institutions may or may not have ready access to clinical staff able to interpret the medical significance of research findings to participants. The addition of clinical consultants may not improve the research study, but may substantially increase the cost of the study. Disclosure of incidental findings with immediate clinical significance may benefit participants' health in the arena of early detection, diagnosis, and treatment. Long-term benefits may include improved quality of life, information that can contribute to future planning related to health status, and avoidance of the need for invasive or risky treatments. Short- or long-term risks include anxiety associated with incidental findings that are "suspicious" and increased medical expenses for individuals who pursue the clinical significance of incidental findings. However, incidental findings of immediate clinical significance should be relayed to research participants or their primary physicians in a timely manner and consistent with informed consent.

Informed Consent⁵ and Disclosure of Incidental Findings: Points to Consider Related to Institutional Resources

A consideration of resources available to various research settings involves balancing the benefits and burdens of requiring that all imaging research studies include clinical experts to interpret the clinical significance of incidental findings. The ethical tension involves:

• Considerations of fairness to basic scientists working independently of clinical research settings versus clinical experts with ready access to approved technology
• The burden of increasing costs of research for recruiting and maintaining clinical expertise
• The state of acceptance among clinical experts of the specific imaging technology under study and confidence with which investigators can interpret images
• The likelihood of incidental findings in the particular study population

Participants in the meeting on "Detection and Disclosure of Incidental Findgs in Neuroimaging Research" agreed on both the importance of imaging research, and that uncertainty about handling incidental findings should not impede meritorious research. The report's final recommendation was:

"Guidelines for detection and disclosure of incidental findings should highlight the responsibility of the research team, but should not stand in the way of neuroimaging research."²

Resources available to research settings are directly relevant to handling of incidental findings and the information that should be covered during the informed consent process. Investigators and research teams are encouraged to consider the appropriate information to disclose to research participants about incidental findings in the context of available resources. Institutions may or may not have access to clinical experts and approved diagnostic technology. If these resources are available and consent is provided by potential participants, it may be appropriate to disclose information about incidental findings along with the expert consultant's evaluation of clinical significance. Conversely, if such resources are not available, it may be appropriate to inform participants that they may obtain copies of their images for assessment by a private physician. Thus, the absence of clinical expertise in research settings should not preclude imaging research; however, it will have an impact on information that can be disclosed and the information provided during informed consent, including information about incidental findings.

Points to consider regarding informed consent include:

Settings where investigators have or have ready access to individuals with the expertise to conduct clinical evaluations of acquired scans:

• Informed consent should include a description of policies/procedures for detecting, disclosing, and managing incidental findings.
• Informed consent should specify permissions either to inform research participants or their primary medical care provider regarding incidental findings.
• Informed consent will include descriptions of responsibilities of research institution, the investigator(s), the clinical radiologist, and the participant's primary medical care provider.
• In those cases where the participant does not have a primary medical care provider, the clinical radiologist should communicate with the research participant, consistent with informed consent, to advise her/him to seek a provider or to provide a list of potential providers to whom incidental findings could be sent.

Settings where investigators have neither the expertise nor ready access to clinical expertise:

• The informed consent process should provide information to research participants to inform them that the study results cannot and will not be reviewed for incidental findings.
• Imaging protocols should not require that research personnel receive training in the detection of incidental findings.

Disclosure of Incidental findings: Points to Consider Related to Ethical and Legal Implications

A consideration of consequences of disclosure of incidental findings to research participants should involve a favorable balance of potential benefits versus risks.

The disclosure of incidental findings may benefit research participants in the short and/or long term. Examples include:

• Improved quality of life
• Information that is useful for future planning related to prevention and treatment
• Avoidance of diagnostic or treatment procedures where none may be needed

The disclosure of incidental findings may burden research participants in the short and/or long term. Examples include:

• Psychological distress
• Financial burdens to participants
• Discrimination by employers and/or health plans
• Violations of cultural norms

Research participants should be given the opportunity to express a preference as to: 

• Whether or not they wish to be informed of incidental findings
• The types of incidental findings they prefer to know and not know

Research participants should be aware that there are legal requirements unrelated to research for reporting suspected or confirmed findings of child or spousal abuse. If a research participant specifies that incidental findings be disclosed to their physician or assessed by clinical consultants, qualified research staff should share findings in a manner consistent with both informed consent and Federal and State laws.

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Summary

When designing imaging research, investigators should give careful thought to processes for handling incidental findings that may occur during the course of their studies. The NIBIB is encouraging investigators to consider the following recommendations²:

• Imaging protocols performed in a research project should focus on what is needed to address the aims of the research (i.e., additional protocols for diagnostic purposes should not be performed unless mandated by institutional policy).
• Researchers should anticipate the potential for incidental findings in research design and establish a process for responding to incidental findings consistent with institutional policies and procedures.
• The management of the incidental findings process should allow for the inclusion of a professional (e.g., a clinical radiologist) who is competent to interpret imaging scans for clinically significant findings.
• Incidental findings should be addressed specifically in the informed consent process and should include a discussion of how incidental findings will be reviewed and provided to research participants.
• Incidental findings should be included in the investigator's Progress Reports to the NIBIB.

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References

¹ Illes J. et al. 2006. "Incidental Findings in Brain Imaging Research," Science, 311: 783-784.

² National Institute of Neurological Disorders and Stroke. "Detection and Disclosure of Incidental Findings in Neuroimaging Research," Jan. 6-7, 2005. http://www.ninds.nih.gov/news_and_events/proceedings/ifexecsummary.htm

 ³ NIMH Council Workgroup on MRI Research Practices, 2005. "MRI Research Safety and Ethics: Points to Consider"

⁴ Illes J. et al. 2004. "Ethical consideration of incidental findings on adult brain MRI in research." Neurobiology, 62: 888-890.

⁵ Reference when published: Illes J, Kirchen MP, Edwards E, Stanford LR, Bandettini P, Cho M, Ford PJ, Glover GH, Kulynych J, Macklin R, Michael DB, Wolf SM. "Practical Approaches to Incidental Findings in Brain Imaging Research." Neurobiology (submitted 4/30/2007).

NIBIB Point of Contact

Questions about this document should be addressed to:

Valery Gordon, Ph.D., M.P.H.
Acting Director, Office of Extramural Policy
gordonv@mail.nih.gov
(301) 451-0161