Choosing a good research design involves more than just selecting a particular method. Researchers must determine whether the methods they plan on using are ethical. That is, when designing a research study, investigators must do so in a way that does not violate the rights of people who participate. To verify that every research project has these protec­tions, local panels of experts and community repre­sentatives review proposed studies before any data are collected. Only with the approval of this panel can scientists begin their study. If the review panel objects to some aspects of the proposed study, the researcher must revise those aspects and present them anew for the panel’s approval. Likewise, each time a component of a study is changed, the review panel must be informed and give its approval.

To guide review panels, professional organizations (e. g., the American Psychological Association) and government agencies (e. g., the National Institutes of Health) have codes of conduct that specify the rights of research participants and procedures to protect these participants. The following essential guidelines are included in all of these codes:

• Minimize risks to research participants. Use methods
that have the least potential for causing harm or


stress for research participants. During the research, monitor the procedures to be sure to avoid any unforeseen stress or harm.

• Describe the research to potential participants so they can determine whether they wish to participate. Prospective participants must be told the purpose of the project, what they will be asked to do, whether there are any risks or potential harm, any benefits they may receive, that they are free to discontinue participation at any time without penalty, that they are entitled to a complete debriefing at the end of the project, and any other relevant information the review panel deems appropriate. After the study has been explained, participants sign a document that says they understand what they will do in the study. Special caution must be exercised in obtaining consent for the participation of children and adolescents, as well as people who have conditions that affect intellectual functioning (e. g., Alzheimer’s disease, severe head injury). In these cases, consent from a parent, legal guardian, or other responsible person, in addition to the agreement of the person him – or herself, is necessary for participation.

• Avoid deception; if participants must be deceived, provide a thorough explanation of the true nature of the experiment as soon as possible. Providing complete information about a study in advance sometimes biases or distorts a person’s responses.

Consequently, investigators may provide participants with partial information about the study or even mislead them about its true purpose. As soon as it is feasible—typically just after the experiment—any false information that was given to research participants must be corrected, and the reasons for the deception must be provided.

• Results should be anonymous or confidential. Research results should be anonymous, which means that people’s data cannot be linked to their name. When anonymity is not possible, research results should be confidential, which means the identity of participants is known only to the investigator conducting the study.

The requirement for informed consent is very important. If prospective participants cannot com­plete the informed consent procedure themselves, perhaps because they are incapacitated or because they have a condition, such as Alzheimer’s disease, that causes intellectual impairment, special cautions must be taken. The American Geriatrics Society

(2007) , among other professional organizations, published guidelines outlining some of these pro­tections. For example, when the participant cannot understand the consent process, someone else (usu­ally a family member) must complete it. In addi­tion, the researcher must describe the procedures to the participant and still obtain the participant’s assent. However, this process is task specific; some cognitively impaired people, particularly early in the disease process, can respond appropriately to certain types of consent. And researchers can obtain advance consent for future participation when the cognitive impairment is more severe. In all cases, though, researchers must take extra precautions to be sensitive to these individuals; for example, if it becomes apparent that the participant does not like the procedures, the researcher must stop collecting data from that individual.

These ethical principles provide important pro­tections for participants and investigators alike. By treating research participants with respect, inves­tigators are in a better position to make important discoveries about adult development and aging.

Concept Checks

1. What are the three major approaches to measuring a behavior or topic of interest?

2. What are the key differences among experimental, correlational, and case study designs?

3. What three basic effects are examined in all developmental research?

4. What are the advantages and disadvantages of cross­sectional, longitudinal, and sequential designs?

5. What are the limitations of the extreme age groups design?

6. What steps do researchers need to take before conducting a study involving human participants?

Studying Adult Development and Aging