Situation: A public health nurse at the municipal health office joins a research team that will study how to reduce low birth weight among babies born in the municipality. A 30-year-old pregnant woman who is fully alert and able to decide for herself, but cannot read, says she wants to join the study. How should the nurse obtain her informed consent?

Research participation requires express informed consent from the competent adult herself. When a participant cannot read, the consent information is read to her in a language she understands, her understanding is checked, and an impartial witness observes the process and attests that she agreed freely; she then signs or places her thumbmark. Inability to read does not make her incompetent, so no one decides for her.

Core ethical principle: autonomy and decisional capacity

A 30-year-old pregnant woman who is fully alert and able to decide for herself is a competent adult. In research ethics, the inability to read is a communication barrier, not a loss of decisional capacity. Therefore, the consent must be obtained from the woman herself, never from a substitute decision-maker such as her husband. The principle of respect for persons is operationalized through the informed consent process, and it protects the participant’s autonomy ^[1][4].

Why option 1 is correct

When a participant cannot read, the consent information is read aloud in a language she understands, and her comprehension is verified before she agrees. An impartial witness observes the entire process and attests that the participant understood the information and consented freely and voluntarily ^[1][4]. The participant then signs or places a thumbmark on the consent form. This approach preserves the woman’s autonomy while accommodating her literacy limitation.

Why the other options are incorrect

Option	Problem
2. Give the form to take home so a relative can read it	This transfers the consent discussion to an untrained person and does not verify understanding in a controlled, witnessed setting. The researcher remains responsible for ensuring comprehension [1][3].
3. Ask her husband to read and sign on her behalf	This violates autonomy. A competent adult must consent for herself; a spouse cannot substitute for her decision [1][4].
4. Record verbal agreement and skip the signed form	Informed consent requires both a process and documentation. The signed form or thumbmark serves as evidence of the process [1][2].

Informed consent as a process, not a single event

Informed consent is not merely obtaining a signature. It is a continuous process in which the researcher explains the nature, procedures, risks, benefits, and treatment schedules of the study in non-technical, understandable language ^[1][2]. The consent document has two parts: the Subject Information Sheet and the Informed Consent Form ^[1][2]. Both must be approved by an Institutional Ethics Committee before use ^[1].

Special considerations in low-literacy settings

In settings with low literacy levels, ensuring that participants are fully informed before consenting is a recognized challenge ^[3]. Researchers must adapt consent tools to the socio-cultural environment and use strategies such as verbal explanation, witnessed consent, and thumbmarks to maintain ethical standards ^[3][4]. The role of the independent witness becomes especially important in these contexts to confirm that the participant understood and agreed without coercion ^[4].

Key point! Illiteracy does not equal incompetence. The participant retains the right to decide for herself; the nurse’s role is to remove the communication barrier, not to bypass her autonomy. Watch out! Never let a family member sign for a competent adult unless the adult is legally determined to lack decisional capacity.