Guidance on switching from prescription to non-prescription status: Consumer use studies

On this page

• Overview of consumer use studies
• Label comprehension studies
• Self-selection studies
• Actual use studies
• Human factors studies

Overview of consumer use studies

Consumer use studies help provide evidence that consumers can use the proposed product safely and effectively without practitioner oversight.

There are 4 main types of consumer use studies:

• label comprehension studies
• self-selection studies
• actual use studies
• human factors studies

Health Canada typically requests the applicant to provide 1 or a combination of these types of consumer use studies in switch submissions. The applicant is encouraged to discuss the need for consumer use studies with us before filing their submission.

Ideally, consumer use studies should be conducted using study subjects who are representative of Canadian demographics.

In terms of language, in some cases, consumer use studies can be conducted solely in English or French if the text of the other language on the product label is an accurate translation of the tested label. In other cases, such as for all label comprehension studies, Health Canada may request that studies be conducted in both official languages. We will give consideration to consumer use studies conducted in French- or English-speaking foreign countries on a case-by-case basis, if equivalent studies are not available for the Canadian population.

The applicant may choose to follow methodologies for consumer use studies suggested by other regulatory agencies. For example, the United States Food and Drug Administration (US FDA) has developed the following documents:

• Guidance for industry: Label comprehension studies for nonprescription drug products (2010)
• Guidance for industry: Self-selection studies for nonprescription drug products (2013)
• Applying human factors and usability engineering to medical devices (2016)

Applicants can discuss their choice of methodologies at a pre-submission meeting.

Label comprehension studies

Central to justifying a switch is the demonstration that the labelling effectively supports the consumer using the proposed product without the involvement of a practitioner. Label components can include the outer and inner product labels and package inserts. A label comprehension study assesses the consumer’s understanding of the major communication elements (for example, the indication, dose and warnings) that relate to the safe and effective use of the product.

The labels used in the label comprehension studies should be as close as possible to the final proposed label to be included in the switch submission.

Label comprehension studies should include a heterogeneous group of subjects, representative of the general population, that vary in age, sex and level of literacy. In some instances, studies may need to address other relevant populations, such as those with other underlying medical conditions or concomitant medications.

Studies should include individuals who have a low level of literacy as assessed by a validated instrument such as the:

• Rapid Estimate of Adult Literacy in Medicine (REALM) test
• Test of Functional Health Literacy in Adults (TOFHLA)
• Short Test of Functional Health Literacy in Adults in French (Fren-STOFHLA)

Proper study design and an appropriately constructed questionnaire are critical for an accurate interpretation of the study results. Note: Online questionnaires are not acceptable evidence, due to the increased risk of bias.

The applicant needs to include a comprehensive statistical analysis plan in the study protocol being provided to Health Canada. They should also provide an analysis of both quantitative and qualitative data to support and interpret study findings. The applicant should organize the results by age cohorts (such as adolescents and adults, where applicable) and literacy levels.

In general, a pre-specified target threshold of 80% or higher is expected for the major communication elements relating to safety and efficacy depending on the level of risk. These label elements include, for example:

• indication
• treatment duration
• route of administration
• dose and dosing interval
• medicinal ingredient(s) and strength(s)
• circumstances requiring the consumer to stop treatment and seek medical advice
• risk information such as precautions, warnings, contraindications and interactions with other medication or food

Self-selection studies

Label comprehension studies do not necessarily predict correct self-selection or the actual way the consumer will use the proposed product. Therefore, self-selection studies are conducted to test whether consumers can apply the label information to their personal medical situations and make correct decisions to use or not use the product.

In self-selection studies, researchers answer the following key questions:

• Can consumers identify the purpose of the product?
• Based on their health conditions, can they demonstrate good judgment about whether the product is right for them?

Self-selection studies, therefore, assess the ability of consumers to determine whether a product is appropriate for them based on their personal health history and the recommended use(s) of the product, dosing, precautions, warnings and contraindications specified on the proposed product label.

Self-selection studies involve using:

• well-planned recruitment and sampling strategies
• a well-developed and pre-tested questionnaire
• specifically trained interviewers to ask the questions

Exclusion criteria should be minimal and limited to the inability to speak, read or understand either official language.

Open-ended questions should be asked to assess the reasons that subjects make incorrect self-selection decisions. Responses to these questions will guide labelling modifications that may be required to improve self-selection.

As is the case with any study, the applicant should include a comprehensive statistical analysis plan in the protocol for the self-selection study that is being submitted to Health Canada. They should also provide an analysis of both quantitative and qualitative data to support and interpret study findings.

Actual use studies

Actual use studies incorporate elements from self-selection and label comprehension studies. They are intended to simulate the way consumers will use the proposed products in a real-life setting.

These studies provide information about:

• consumer compliance and adherence with the product labelling
• safety issues that arise during actual product use

Observation of study participants in the actual use studies can assist in anticipating what the implications would be of removing a practitioner’s involvement in diagnosing the condition, selecting the product and monitoring its use. The design and interpretation of the results of actual use studies are complex.

The applicant should consult the Office of Clinical Trials in the Pharmaceutical Drugs Directorate (PDD) to determine if a clinical trial application is required for their actual use study.

Human factors studies

Human factors studies may be necessary when the proposed switch pertains to a product used with a medical device or a prescription drug-device combination product. These studies provide evidence in support of the safety and efficacy of the medical device with the proposed product for the intended use(s) by consumers and in the intended use environments.

Human factors studies assess the user’s ability to:

• understand the packaging and labelling information
• safely and effectively use the product with the device

These studies also:

• validate the performance of the device
• provide information on device design
• assess the adequacy of the device-user interface in eliminating or mitigating potential use-related hazards