Strength data for female shield-activated autoinjector users.

Area of Science:

• Biomedical Engineering
• Human Factors Engineering
• Medical Device Design

Background:

• Shield-activated autoinjectors are widely used for medication self-administration.
• Limited data exist on the operational force requirements for these devices.
• This study addresses the gap by quantifying female users' maximum force capabilities.

Purpose of the Study:

• To quantify the maximum force capabilities of female autoinjector users.
• To provide data for optimizing autoinjector design and user training.
• To inform force specifications for shield-activated autoinjectors.

Main Methods:

• A study involving 123 female participants across different age groups (young adolescents, adults, elderly).
• Simulated injections were performed using surrogate autoinjectors to measure activation and hold forces.
• Variables included age group, grip type (power and precision), and injection site (abdomen, thigh, upper arm).

Main Results:

• Adults generally exerted higher activation forces compared to other age groups.
• Power grip consistently yielded higher activation forces than precision grip across all injection sites.
• Injection site influenced force, with the thigh potentially allowing higher forces with a power grip.

Conclusions:

• Ecologically valid strength data for female autoinjector users were generated.
• Findings can inform force specifications for shield-activated autoinjectors.
• Optimal grip types and injection sites for maximizing force were identified for training purposes.