Optimal Usability Test Procedure Generation for Medical Devices

Medical device usability testing offers many benefits, including finding medical device usage errors and providing safety to users. As usability testing becomes mandatory for medical devices, manufacturers are increasing the cost burden. In order to perform a high-quality usability test, it is important to implement a usability test procedure, but guidelines for this are lacking. In this paper, we propose a method to systematically design and implement a usability test procedure. We propose methods to reduce test time-costs and apply them to implement the final procedure. Next, by applying the proposed method to sinus surgical navigation system, it is shown that the total time was reduced by 21% compared to the usability summative test procedure previously used in the same system.

Implementing lateral flow devices in long-term care facilities: experiences from the Liverpool COVID-19 community testing pilot in care homes- a qualitative study

Introduction

Antigen-based lateral flow devices (LFDs) offer the potential of widespread rapid testing. The scientific literature has primarily focused on mathematical modelling of their use and test performance characteristics. For these tests to be implemented successfully, an understanding of the real-world contextual factors that allow them to be integrated into the workplace is vital. To address this gap in knowledge, we aimed to explore staff’s experiences of integrating LFDs into routine practice for visitors and staff testing with a view to understand implementation facilitators and barriers.

Methods

Semi-structured interviews and thematic analysis.

Results

We identified two main themes and five subthemes. The main themes included: visitor-related testing factors and staff-related testing factors. Subthemes included: restoring a sense of normality, visitor-related testing challenges, staff-related testing challenges, and pre-pilot antecedent factors.

Conclusion

Our study demonstrates that the real-world implementation of LFDs to test visitors and staff faces significant challenges as a result of several contextual factors negatively affecting the work practice and environment. More comprehensive studies are needed to identify and inform effective implementation strategies to ensure that LFDs can be adopted in an agile way that better supports an already exhausted and morally depleted workforce.

Rapid point-of-care testing for COVID-19: quality of supportive information for lateral flow serology assays

OBJECTIVE

There is a lack of evidence addressing several important human factors questions pertaining to the quality of supportive information provided by commercial manufacturers that can affect the adoption and use of lateral flow serology assays in practice. We aimed to: (1) identify and assess the quality of information that commercial manufacturers provided for their point-of-care tests (POCTs) and (2) examine the implications of these findings on real-world settings.

DESIGN

We used a content analysis methodology in two stages to systematically, code and analyse textual data from documents of commercial manufacturers. A deductive approach was applied using a coding guide based on the validated Point-of-Care Key Evidence Tool (POCKET) multidimensional checklist. An inductive approach was used to identify new patterns or themes generated from our textual analysis.

SETTING

Publicly available supportive information documents by commercial manufacturers for lateral flow serology, were identified and gathered from online searches.

PARTICIPANTS

Supportive information documents retrieved from online searches over 3 months (March 2020 to June 2020).

RESULTS

A total of 79 POCTs were identified that met the study inclusion criteria. Using the POCKET coding guide, we found that the quality of information varied significantly between the manufacturers and was often lacking in detail. Our inductive approach further examined these topics and found that several statements were vague and that significant variations in the level of details existed between manufacturers.

CONCLUSIONS

This study revealed significant concerns surrounding the supportive information reported by manufacturers for lateral flow serology assays. Information transparency was poor and human factor issues were not properly addressed to mitigate the risk of improper device use, although it should be noted that the results of our study are limited by the data that manufactures were prepared to disclose. Overall, commercial manufacturers should improve the quality and value of information presented in their supporting documentation.

Is the LITE version of the usability metric for user experience (UMUX-LITE) a reliable tool to support rapid assessment of new healthcare technology?

OBJECTIVE

To ascertain the reliability of a standardised, short-scale measure of satisfaction in the use of new healthcare technology i.e., the LITE version of the usability metric for user experience (UMUX-LITE). Whilst previous studies have demonstrated the reliability of UMUX-LITE, and its relationship with measures of likelihood to recommend a product, such as the Net Promoter Score (NPS) in other sectors no such testing has been undertaken with healthcare technology.

MATERIALS AND METHODS

Six point-of-care products at different stages of development were assessed by 120 healthcare professionals. UMUX-LITE was used to gather their satisfaction in use, and NPS to declare their intention to promote the product. Inferential statistics were used to: i) ascertain the reliability of UMUX-LITE, and ii) assess the relationship between UMUX-LITE and NPS at different stages of products development.

RESULTS

UMUX-LITE showed an acceptable reliability (α = 0.7) and a strong positive correlation with NPS (r = 0.455, p < .001). This is similar to findings in other fields of application. The level of product development did not affect the UMUX-LITE scores, while the stage of development was a significant predictor (R² = 0.49) of the intention to promote.

DISCUSSION AND CONCLUSION

Practitioners may apply UMUX-LITE alone, or in combination with the NPS, to complement interview and 'homemade' scales to investigate the quality of new products at different stages of development. This shortened scale is appropriate for use in the context of healthcare in which busy professionals have a minimal amount of time to support innovation.

Evidence of bioequivalence and positive patient user handling of a tocilizumab autoinjector

BACKGROUND

The anti-interleukin-6 receptor antibody tocilizumab is approved for subcutaneous injection using a prefilled syringe (PFS). We report results from a bioequivalence study in healthy subjects and a user-handling study in patients with rheumatoid arthritis (RA) using an autoinjector (AI) for tocilizumab.

METHODS

A randomized crossover study in healthy subjects (N = 161) examined the bioequivalence, safety, and tolerability of tocilizumab after a single subcutaneous injection by AI versus PFS. A nonrandomized observational, real-life human factors study in RA patients (N = 54) assessed user (RA patients, caregivers, health care providers) ability to administer tocilizumab effectively by AI.

RESULTS

Bioequivalence criteria for tocilizumab AI versus PFS were met for key pharmacokinetic parameters. Safety was comparable between devices and consistent with the established tocilizumab profile. In the real-life human factors study, the proportion of users who successfully performed all essential tasks required to operate the AI to deliver the full dose was 92.3% at first assessment and 98.1% at second assessment, with no safety concerns.

CONCLUSIONS

Tocilizumab administration by AI was bioequivalent to administration by PFS. Intended users were successful in performing the tasks required to administer tocilizumab by AI. No new safety signals were observed in either study.

CLINICAL TRIAL REGISTRATION

NCT02678988, NCT02682823.

Aptamer-Based Sandwich Assay for Measurement of Thymidine Kinase 1 in Serum of Cancerous Patients

Thymidine kinase 1 (TK1) is traditionally a serum biomarker that is elevated in the early stages of malignancies. The diagnostic and prognostic role of TK1 for screening and monitoring human malignancies has recently been investigated. Anti-human TK1 aptamers were selected through 12 iterative rounds of systematic evolution of ligands by exponential enrichment from a DNA library. The aptamer pool of round 12 was amplified, and the polymerase chain reaction product was cloned on the TA vector. Of the 85 colonies obtained, 52 were identified as positive clones. These aptamers were screened for TK1 with surface plasmon resonance, where apta37 and apta69 showed the highest affinity for TK1. The TK1_apta37 and TK1_apta69 aptamers were used in a sandwich assay platform and successfully detected TK1 in the concentration range of 54-3500 pg mL^-1. Clinical samples from 60 cancerous patients were also tested with this assay system and compared using the conventional antibody-based enzyme-linked immunosorbent assay kit. The aptamer sandwich assay demonstrated a dynamic range for TK1 at clinically relevant serum levels, covering subpicogram per milliliter concentrations. The new approach offers a simple and robust method for detecting serum biomarkers that have low and moderate abundance. The results of this study demonstrate the screening capability of the aptamer sandwich assay platform and its potential applicability to the point-of-care testing system.

Designing medical technology for resilience: integrating health economics and human factors approaches

INTRODUCTION

The slow adoption of innovation into healthcare calls into question the manner of evidence generation for medical technology. This paper identifies potential reasons for this including a lack of attention to human factors, poor evaluation of economic benefits, lack of understanding of the existing healthcare system and a failure to recognise the need to generate resilient products. Areas covered: Recognising a cross-disciplinary need to enhance evidence generation early in a technology's life cycle, the present paper proposes a new approach that integrates human factors and health economic evaluation as part of a wider systems approach to the design of technology. This approach (Human and Economic Resilience Design for Medical Technology or HERD MedTech) supports early stages of product development and is based on the recent experiences of the National Institute for Health Research London Diagnostic Evidence Co-operative in the UK. Expert commentary: HERD MedTech i) proposes a shift from design for usability to design for resilience, ii) aspires to reduce the need for service adaptation to technological constraints iii) ensures value of innovation at the time of product development, and iv) aims to stimulate discussion around the integration of pre- and post-market methods of assessment of medical technology.