Do you really know your consumers? : analyzing the impact of consumer knowledge on use and failure evaluation of consumer electronics

The field of Consumer Electronics (CE) can be characterized by continuous technological innovation, fierce global competition, strong pressure on time-to-market, fast adoption cycles and increasingly complex business processes. In this context it is increasingly challenging for product designers and developers to provide products with unique features and excellent price / performance characteristics, as well as having to provide products that meet all the consumer’s expectations. From a business perspective, research has shown that the number of consumer complaints and even product returns is increasing for complex CE (Den Ouden, 2006). Further research on the causes of these complaints showed that almost half of the complaints were due to non-technical reasons. Therefore, more insight is needed into product quality and reliability from a consumer point of view. A literature review showed that quality and reliability methods that are currently used in product development insufficiently prevent the large variety of consumer complaints: the number of consumer complaints is rising while at the same time the root cause of these complaints is more difficult to retrace. Product failures need to be measured and analyzed from a consumer’s point of view since the traditional fault-complaint propagation model fails to capture all potential sources of consumer complaints. More insight is needed into the relation between the diversity of consumers and the propagation of product development faults to these "Consumer-Perceived Failures" (CPFs).A conceptual framework was developed to model the underlying factors related to the propagation of product development faults to consumer complaints from a consumer point of view. This framework is based on insights from human-computer interaction and consumer behavior literature and the results of an explorative experiment. Furthermore, the most commonly used consumer selection criteria for consumer tests based on demographics and/or product adoption related characteristics do not sufficiently cover differences in CPFs. The consumer characteristic "consumer knowledge" is hypothesized to have a strong impact on differences in the underlying variables of this framework. A review of relevant consumer models and consumer characteristics used in human-computer interaction and consumer behavior research shows that this construct relates to cognitive structures consumers have about a product’s functioning as well as cognitive processes needed to use a complex CE product. This dissertation therefore aimed to investigate the hypothesized effect of consumer knowledge on two important variables of the conceptual framework: product usage behavior and failure attribution. By using multiple surveys, two laboratory experiments and a web-based experiment, the following aspects of the conceptual framework were investigated in this dissertation: • How and to what extent consumers can be differentiated on knowledge of complex CE • The effect of consumer knowledge on differences in product usage behavior • The effect of consumer knowledge on differences in attribution of product failures The results of the surveys to differentiate consumers on knowledge (both core and supplemental domains) of innovative LCD televisions demonstrated the successful development and validation of measurements of both subjective and objective measurements of expertise and familiarity. It was concluded that the selection of consumer knowledge constructs as criterion for differentiating consumers for a consumer test depends on the target consumer group for a product (e.g. a very narrow homogeneous consumer group versus mass consumer markets), the type of product (e.g. passive versus active interaction) and the goal of the consumer test. The laboratory experiment which investigated the effect of subjective expertise and objective familiarity on product usage behavior showed that higher levels of subjective expertise on both the television and computer domain result in significantly better effectiveness and efficiency and less interaction problems when performing complex product related tasks. Next, the results also showed that differences in subjective expertise stronger relate to differences in product usage behavior than those in objective familiarity. The findings of this study help product developers and designers to better understand differences in product usage behavior when consumers encounter interaction problems and can therefore help the product designers and developers to take better design decisions.The results of both failure attribution experiments with simulated failure scenarios of picture quality failures in an LCD television showed that only objective expertise differences affect differences in consumer perception of product failures. However, although the failure attribution of consumers with higher levels of objective expertise has more dimensions and is more refined, higher levels of objective expertise on a product do not automatically result in attributions that are more in accordance with the real physical cause of the failure. This has important implications because currently used test methods often differentiate consumers only on previous experience (i.e. familiarity) with a product. The results of both studies also demonstrated that both failure cause and failure impact do not significantly affect how consumers attribute the failures. In total it can be concluded that, when evaluating the effect of consumer diversity on fault-complaint propagation, consumer knowledge can be used to differentiate product use and failure attribution for complex CE. However, it should be noted that especially for failure attribution this effect is not consistent across different types of failures. In addition, compared to objective and subjective familiarity and subjective expertise, objective expertise has the strongest impact. In the context of fast evolving complex CE, objective expertise measurements are becoming increasingly important because familiarity or subjective expertise measurements on the (technical) functioning of currently available products can quickly become "incorrect" or "incomplete" for the next generation of products. These insights can support product designers and developers to make the right design decisions to enhance consumer satisfaction

Doctors' knowledge of patient radiation exposure from diagnostic imaging requested in the emergency department

Objective: To assess emergency department (ED) doctors' knowledge of radiation doses associated with diagnostic imaging and to describe their practice with regard to informing patients of risk. Design, participants and setting: Prospective, questionnaire-based observational study in May 2009 among all 110 doctors in the EDs of a 570-bed teaching hospital and a 200-bed district hospital. Main outcome measures: Percentage knowledge score; and frequency of discussing radiation risk with patients, based on responses to three scenarios rated on a visual analogue scale (VAS), where a score of 100 indicates doctors would always discuss it. Results: 96 doctors (87%) completed the questionnaire. The overall mean knowledge score was 40% (95% CI, 38%-43%). Senior doctors scored somewhat higher than junior doctors, but not significantly (42% v 39%; P = 0.75). Over three-quarters of doctors (78%) underestimated the lifetime risk of fatal cancer attributable to a single computed tomography scan of the abdomen. Most doctors (76%) reported never having had any formal training on risks to patients from radiation exposure. The frequency at which doctors would inform patients of the risk of radiation varied greatly depending on the clinical scenario (mean VAS scores, between 38 and 90). Conclusion: Emergency doctors in our sample had a varied knowledge of the risks from radiation exposure, but overall knowledge was poor. Staff should receive education, and the diagnostic imaging request process may need to include information on radiation doses and risks.Griffith Health, School of MedicineFull Tex

The Effect of Mechanical Resonance on Josephson Dynamics

We study theoretically dynamics in a Josephson junction coupled to a mechanical resonator looking at the signatures of the resonance in d.c. electrical response of the junction. Such a system can be realized experimentally as a suspended ultra-clean carbon nanotube brought in contact with two superconducting leads. A nearby gate electrode can be used to tune the junction parameters and to excite mechanical motion. We augment theoretical estimations with the values of setup parameters measured in the samples fabricated. We show that charging effects in the junction give rise to a mechanical force that depends on the superconducting phase difference. The force can excite the resonant mode provided the superconducting current in the junction has oscillating components with a frequency matching the resonant frequency of the mechanical resonator. We develop a model that encompasses the coupling of electrical and mechanical dynamics. We compute the mechanical response (the effect of mechanical motion) in the regime of phase bias and d.c. voltage bias. We thoroughly investigate the regime of combined a.c. and d.c. bias where Shapiro steps are developed and reveal several distinct regimes characteristic for this effect. Our results can be immediately applied in the context of experimental detection of the mechanical motion in realistic superconducting nano-mechanical devices.Comment: 18 pages, 11 figure

Appropriateness of antibiotic prescribing in the Emergency Department

Background Antibiotics are some of the most commonly prescribed drugs in the Emergency Department (ED) and yet data describing the overall appropriateness of antibiotic prescribing in the ED is scarce. Objectives To describe the appropriateness of antibiotic prescribing in the ED. Methods A retrospective, observational study of current practice. All patients who presented to the ED during the study period and were prescribed at least one antibiotic were included. Specialists from Infectious Disease, Microbiology and Emergency Medicine and a Senior Pharmacist assessed antibiotic appropriateness against evidence-based guidelines. Results A total of 1019 (13.6%) of patient presentations involved the prescription of at least one antibiotic. Of these, 640 (62.8%) antibiotic prescriptions were assessed as appropriate, 333 (32.7%) were assessed as inappropriate and 46 (4.5%) were deemed to be not assessable. Adults were more likely to receive an inappropriate antibiotic prescription than children (36.9% versus 22.9%; difference 14.1%, 95% CI 7.2%–21.0%). Patients who met quick Sepsis-related Organ Failure Assessment (qSOFA) criteria were more likely to be prescribed inappropriate antibiotics (56.7% versus 36.1%; difference 20.5%, 95% CI, 2.4%–38.7%). There was no difference in the incidence of appropriate antibiotic prescribing based on patient gender, disposition (admitted/discharged), reason for antibiotic administration (treatment/prophylaxis) or time of shift (day/night). Conclusions Inappropriate administration of antibiotics can lead to unnecessary adverse events, treatment failure and antimicrobial resistance. With over one in three antibiotic prescriptions in the ED being assessed as inappropriate, there is a pressing need to develop initiatives to improve antibiotic prescribing to prevent antibiotic-associated patient and community harms.No Full Tex

Nurse practitioner administered point-of-care ultrasound compared with X-ray for children with clinically non-angulated distal forearm fractures in the ED: A diagnostic study

Paediatric distal forearm fractures are a common ED presentation. They can be diagnosed with point-of-care ultrasound (POCUS) as an alternative to X-rays. Given that ED nurse practitioners (NPs) are relied on for the diagnosis of paediatric fractures, it is important to describe the diagnostic accuracy of NP-conducted POCUS versus X-ray.This prospective diagnostic study was conducted in a tertiary paediatric hospital in Queensland, Australia, between February 2018 and April 2019. Participants were children aged 4-16 years with a clinically non-angulated, suspected distal forearm fracture. Diagnosis from 6-view NP-administered POCUS of the distal radius and ulna was compared against the reference standard of 2-view X-ray. Each patient received both imaging modalities. Overall forearm diagnosis was classified as 'no', 'buckle' or 'other' fracture for both modalities. The primary outcome was diagnostic accuracy for 'any' fracture ('buckle' and 'other' fractures combined). Secondary outcomes included diagnostic accuracy for 'other' fractures versus 'buckle' and 'no' fractures combined, and pain, imaging duration and preference for modality.Of 204 recruited patients, 129 had X-ray-diagnosed forearm fractures. The sensitivity and specificity for NP-administered POCUS were 94.6% (95% CI 89.2% to 97.3%) and 85.3% (95% CI 75.6% to 91.6%), respectively. 'Other' fractures (mostly cortical breach fractures), when compared with 'buckle'/ 'no' fractures, had sensitivity 81.0% (95% CI 69.1% to 89.1%) and specificity 95.9% (95% CI 91.3% to 98.1%). Pain and imaging duration were clinically similar between modalities. There was a preference for POCUS by patients, parents and NPs.NP-administered POCUS had clinically acceptable diagnostic accuracy for paediatric patients presenting with non-angulated distal forearm injuries. This included good sensitivity for diagnosis of 'any' fracture and good specificity for diagnosis of cortical breach fractures alone. Given the preference for POCUS, and the lack of difference in pain and duration between modalities, future research should consider functional outcomes comparing POCUS with X-ray in this population in a randomised controlled trial

Advanced therapy for pulmonary arterial hypertension due to congenital heart disease: a clinical perspective in a new therapeutic era

Cardiolog

Derivation of a clinical decision-making aid to improve the insertion of clinically indicated peripheral intravenous catheters and promote vessel health preservation. An observational study

Background It is well established that the idle peripheral intravenous catheter (PIVC) provides no therapeutic value and is a clinical, economic and above all, patient concern. This study aimed to develop a decision aid to assist with clinical decision making to promote clinically indicated peripheral intravenous catheter (CIPIVC) insertion in the emergency department (ED) setting. Providing evidence for a uniform process could assist clinicians in a decision-making process for PIVC insertion. This could enable patients receive appropriate vascular access healthcare. Methods We performed a secondary analysis of data from a multicentre cohort of emergency department clinicians who performed PIVC insertion. We defined CIPIVC a priori as one used for a specific clinical treatment and or procedure such as prescribed intravenous (IV) fluids; prescribed IV medication; or IV contrast (for computerized tomography scans). We sought to refute or validate an assumption if the clinician performing or requesting the insertion decided the patient was >80% likely to need a PIVC. Using logistic regression, we derived a decision aid for CIPIVCs. Results In 817 patients undergoing PIVC insertion, we observed 68% of these to be CIPIVCs. Admitted patients were significantly more likely to have a CIPIVC, Odds Ratio (OR) = 3.05, 95% confidence interval (CI) = 2.17–4.30, p = <0.0001. Before insertion, patients who definitely needed IV fluids/medicines OR = 3.30, 95% CI = 2.02–5.39, p = <0.0001 and who definitely needed a contrast scan OR = 3.04, 95% CI = 1.15–8.03, p = 0.0250 were significantly more likely to have a device inserted for a clinical indication. Patients who presented with an existing vascular access device were more likely to have a new CIPIVC inserted for use OR = 4.35, 95% CI = 1.58–11.95, p = 0.0043. The clinician’s pre-procedural judgment of the likelihood of therapeutic use >80% was independently associated with CIPIVC; OR 3.16, 95% CI = 2.06–4.87, p<0.0001. The area under the receiver operating characteristic curve was 0.81, and at the best cut-off, the model had a specificity of 0.81, sensitivity of 0.71, a positive predictive value of 0.89 and negative predictive value of 0.57. Conclusions Using the derived decision aid, clinicians could ask:- “Does this patient need A-PIVC?” Clinicians can decide to insert a CIPIVCs when: (i) Admission to hospital is anticipated and when (ii) a Procedure requires a PIVC, e.g., computerised tomography scans and where an existing suitable vascular access device is not present and or; (iii) there is an indication for IV fluids and or medicines that cannot be tolerated enterally and are suitable for dilution in peripheral veins; and, (iv) the Clinician’s perceived likelihood of use is greater than 80%.Full Tex

Resuscitation With Early Adrenaline Infusion for Children With Septic Shock: A Randomized Pilot Trial

OBJECTIVES: In children with septic shock, guidelines recommend resuscitation with 40–60 mL/kg of fluid boluses, yet there is a lack of evidence to support this practice. We aimed to determine the feasibility of a randomized trial comparing early adrenaline infusion with standard fluid resuscitation in children with septic shock. DESIGN: Open-label parallel randomized controlled, multicenter pilot study. The primary end point was feasibility; the exploratory clinical endpoint was survival free of organ dysfunction by 28 days. SETTING: Four pediatric Emergency Departments in Queensland, Australia. PATIENTS: Children between 28 days and 18 years old with septic shock. INTERVENTIONS: Patients were assigned 1:1 to receive a continuous adrenaline infusion after 20 mL/kg fluid bolus resuscitation (n = 17), or standard care fluid resuscitation defined as delivery of 40 to 60 mL/kg fluid bolus resuscitation prior to inotrope commencement (n = 23). MEASUREMENTS AND MAIN RESULTS: Forty of 58 eligible patients (69%) were consented with a median age of 3.7 years (interquartile range [IQR], 0.9–12.1 yr). The median time from randomization to inotropes was 16 minutes (IQR, 12–26 min) in the intervention group, and 49 minutes (IQR, 29–63 min) in the standard care group. The median amount of fluid delivered during the first 24 hours was 0 mL/kg (IQR, 0–10.0 mL/kg) in the intervention group, and 20.0 mL/kg (14.6–28.6 mL/kg) in the standard group (difference, –20.0; 95% CI, –28.0 to –12.0). The number of days alive and free of organ dysfunction did not differ between the intervention and standard care groups, with a median of 27 days (IQR, 26–27 d) versus 26 days (IQR, 25–27 d). There were no adverse events reported associated with the intervention. CONCLUSIONS: In children with septic shock, a protocol comparing early administration of adrenaline versus standard care achieved separation between the study arms in relation to inotrope and fluid bolus use

Factors infuencing variation in investigations after a negative CT brain scan in suspected subarachnoid haemorrhage: A qualitative study

Introduction Variation in the approach to the patient with a possible subarachnoid haemorrhage (SAH) has been previously documented. The purpose of this study was to identify factors that influence emergency physicians’ decisions about diagnostic testing after a normal CT brain scan for ED patients with a headache suspicious of a SAH. Methods We conducted an interview-based qualitative study informed by social constructionist theory. Fifteen emergency physicians from six EDs across Queensland, Australia, underwent individual face-to-face or telephone interviews. Content analysis was performed whereby transcripts were examined and coded independently by two co-investigators, who then jointly agreed on the influencing factors. Results Six categories of influencing factors were identified. Patient interaction was at the forefront of the identified factors. This shared decision-making process incorporated ‘what the patient wants’ but may be biased by how the clinician communicates the benefits and harms of the diagnostic options to the patient. Patient risk profile, practice evidence and guidelines were also important. Other influencing factors included experiential factors of the clinician, consultation with colleagues and external influences where practice location and work processes impose constraints on test ordering external to the preferences of the clinician or patient. The six categories were organised within a conceptual framework comprising four components: the context, the evidence, the experience and the decision. Conclusions When clinicians are faced with a diagnostic challenge, such as the workup of a patient with suspected SAH, there are a number of influencing factors that can result in a variation in approach. These need to be considered in approaches to improve the appropriateness and consistency of medical care.No Full Tex