An Original Theory of Culturally Adaptive Human Factors Engineering for Medical Device Design in Nigerian Healthcare Contexts

Human factors engineering principles governing the design of medical device interfaces have been developed predominantly from user studies in high-income country healthcare contexts, encoding assumptions about user literacy, cultural interface conventions, clinical workflow structures, and error recovery behaviours that do not apply uniformly to Nigerian healthcare users, creating a theoretical gap whose consequences are visible in the high rates of medical device use error observed in Nigerian hospitals. This dissertation develops an original theory of culturally adaptive human factors engineering for medical device design in the Nigerian healthcare context, making contributions to both human factors engineering theory and biomedical engineering practice. The theoretical development follows a grounded theory methodology informed by an extensive empirical programme comprising sixty structured usability studies with Nigerian medical device users across six hospitals in Lagos, Kano, Enugu, and Port Harcourt, representing diverse educational backgrounds, clinical specialisations, and device experience levels. Cultural dimensions identified as systematically modifying device interaction include collectivist error-reporting cultures affecting alarm acknowledgement behaviour, multilingual interface navigation patterns, literacy-level-dependent cognitive parsing of alphanumeric versus iconographic interface elements, and power distance effects on device authority override behaviour in hierarchical clinical team contexts. A formal cultural adaptation theory is developed specifying mappings from cultural variable measurements to design parameter modifications for key device interface elements. The theory is operationalized as a culturally adaptive design methodology and applied to redesign the interface of a commercial infusion pump, with comparative usability testing confirming significant error rate reduction in the culturally adapted design relative to the original. Keywords: human factors engineering, medical device design, cultural adaptation, usability, Nigerian healthcare.