Applying the quick exposure check in the workstation design process, physical and virtual prototype assessment.

BACKGROUND: The Quick Exposure Check (QEC) assesses four major body parts and engages users in assessing some physical interactions relevant to design in task analysis. OBJECTIVE: In this paper, we investigated the application of QEC as the ergonomic intervention to detect pre-production ergonomic design faults in the apple sorting machine by applying physical and virtual prototyping for three different tasks analysis divided into two phases (Task 1: Apple harvesting and preparation for sorting; Task 2: Sorting control and separation of waste fruits; Task 3: Transfer of separated apples). METHOD: First, the QEC questionnaire was administered while Iranian participants interacted with the machine to detect abnormal posture. Second, we redesigned a concept of the machine and assessed it with QEC by a focus group. RESULTS: Before design, the high pressure in Task 1 is on the back (dynamic), shoulder/arm, and very high pressure in Task 2, and in Task 3 on the back (static), arm/shoulder/neck, making an uncomfortable situation for posture. After redesign, we observed decreased pressures on the back/shoulder/arm in Task 1 from high to medium, in Task 3 from very high to low, and also in Task 2, this was detectable decreasing from very high pressures on the back/shoulder/arm and the high pressures on the neck to medium. CONCLUSION: Prototyping with QEC demonstrated that accurate redesigning of the machine with concentration on shifting from static tasks to dynamic or conversely, and ease of access by adjusting dimensions according to anthropometry and auxiliary products, could reduce musculoskeletal disorders.

Head and facial dimensions of Chilean workers for design purposes and the differences with other populations.

BACKGROUND: An appropriate match between a product and its end-users requires anthropometric data, which show variations among different countries. Proper Personal Protection Equipment (PPE) fit is key for safety and comfort. Chile had no head and facial anthropometric data available in order to design face/head PPE. OBJECTIVE: To describe face/head anthropometric characteristics of Chilean workers. Additionally, this study compared those dimensions against other populations (United States (US), South Korea and China). METHODS: An anthropometric survey involving 21 measures was conducted between September 2013 to May 2016 using stratified sampling. The measurements were based on ISO/TS 16976-2 and ISO 15535 to ensure the highest standards possible, and a total of 474 workers, aged from 18 to 66 years old, participated in the survey. RESULTS: The biggest differences were in Neck circumference, Weight, Nose breadth, Nose protrusion, Bitragion chin arc, Face length, Subnasale-sellion length, Face width, Bigonial breadth and Bitragion subnasal arc. Head length of Chileans were longer than Chinese and South Korean ones, but shorter than US Head length. Chilean Head breadth is smaller than Chinese and South Korean ones. Chileans Face length was the largest observed. Face width of Chileans was smaller than US and Chinese ones. Gender specific differences were also observed in the inter-country comparisons. Chilean males had larger anthropometric dimensions than females. CONCLUSION: Chilean Head and face dimensions differed significantly when compared against US, South Korean and Chines Head and Face dimensions. Chileans have longer and narrower faces with wider mouths, with a head size in between the US and Asian heads. Face and head PPE for Chileans should use dimensions in the current paper in order to ensure proper fit.

Normative data for handgrip strength in Iranian healthy children and adolescents aged 7-18 years: comparison with international norms.

BACKGROUND: Grip strength is an essential component of physical fitness. The objective of this study was to develop normative handgrip strength data for Iranian healthy boys and girls comparing their handgrip strength with international reference values. METHODS: Handgrip strength was measured in 2637 healthy children/adolescents (1391 boys and 1246 girls), aged 7-18 years, using a standard adjustable Jamar hand dynamometer (Model 5030 J1, Sammons Preston Rolyan, Bolingbrook, IL, USA). Body mass (kg) and stature (cm) were measured and body mass index was computed in kg/m2. The sample was stratified by gender, age, and hand preference. RESULTS: Handgrip strength increased with age and was considerably higher in boys than in girls for all age groups (p < 0.001). Grip strength had a parallel and linear growth for both genders until the age of about 11 years and showed a steeper upward slope in boys than in girls thereafter. The findings of the current investigation were significantly different from those of the previously published normative data, especially for boys over the age of 12 years and girls in the age range of 7-18 years (p < 0.001). This difference was mainly in such a way that the Iranians had lower handgrip strength. CONCLUSIONS: The differences between present results and those of similar available in the literature in this field emphasize the significant role of using normative data specific to a particular population in research or clinical settings.

Developments in work-related upper limb disorders (WRULD) amongst Dutch university students from 2004 to 2014.

BACKGROUND: Former studies on work-related upper limb disorders (WRULD) within university education report substantial prevalence rates. In this study, developments in WRULD amongst students in the period 2004-2014 were investigated. Our findings can be a benchmark for future studies, in particular when there are major societal changes as in the case of the COVID-19 pandemic. OBJECTIVE: Differences in time (academic year), how long students have been studying (year of studying), relations with computer time and societal changes were points of interest. METHODS: 2254 students (average age 20.0 years) responded to a questionnaire on WRULD. Students experiencing complaints were further questioned about the severity of complaints and associated body locations. RESULTS: The average percentage of students experiencing complaints was 57%. The highest prevalence rates and severity scores were found in the first and last recorded academic years. The neck, shoulder, back and wrist were most often indicated. The prevalence of complaints raised from the 1st (49%) to the 4th (75%) year of studying. Two seriousness measures showed highest scores in the 5th/6th/7th year of studying. Relations were found between both the prevalence and seriousness of complaints with reported computer time. CONCLUSIONS: After an initial decreasing trend from the academic year 2006/2007 to 2010/2011 there was an increase in WRULD amongst students from 2010/2011 to 2013/2014. Limiting financial and study time factors may have played a role. Structural attention for WRULD prevention and risk factors seems to be effective in reducing prevalence and severity of WRULD. This seems to be even more necessary due to recent COVID-related changes in the students' lives.

Gender inequality and sexual height dimorphism in Chile.

Chile has experienced significant improvements in its economy; thus, a secular trend in height has been observed in its population. Gender equality has also improved hand in hand with active policies addressing the gender gap in several dimensions (work, education, health) and overall economic improvement. This study examined changes in sexual height dimorphism in four samples of Chilean male and female working-age subjects and attempted to establish associations with gender equality and welfare. Sexual height dimorphism was calculated and compared with gender equality and overall welfare indicators between 1955 and 1995. Sexual height dimorphism reduction was seen to be strongly associated with greater gender equality and some general welfare indicators, such as the infant mortality rate. Gross domestic product per capita was not associated with sexual height dimorphism, but it showed significant associations with gender equality indicators. Overall, the gender gap has been reduced in Chile, which can be observed through improvements in gender equality indicators and a reduction in height dimorphism, mainly in areas associated with women's health. However, gender equality is still far behind in terms of female labour participation and women in political power, which require attention and further improvements.

Application of mismatch equations in dynamic seating designs.

Anthropometry is critical for product and workplace design. Highly prevalent, office work is associated with sedentarism and physical discomfort due to prolonged sitting. Dynamic seating (alternating across sitting, perching, and standing) has been suggested as an alternative to overcome those problems. The current study tested a large sample of anthropometric data for mismatch levels against national and international office furniture standards using dynamic seating as a framework with traditional and perching mismatch equations, applied to three recommended dynamic seating components. Dimensions present in the standards used did not match the majority of the sample. For sitting, seat width and depth individually presented the lowest levels of match, as well as under cumulative fit of all office furniture dimensions. However, these were alleviated when incorporating adjustability. Perching was shown to be generally impeded given commercially-available chair height options. Limitations in state-of-the-art perching equations are discussed, and two new models are proposed as design alternatives. Further research should focus on testing the criteria presented in this research through discomfort and objective measures.

Educational level and its relationship with body height and popliteal height in Chilean male workers.

A secular trend in body height has been experienced in many nations and populations, hypothesized to be the result of better living conditions. Educational level has been shown to be closely associated with body height. This study examined the changes in body height and popliteal height in a group of adult Chilean male workers by age cohort and the relationship of these with educational level. The body heights and popliteal heights of 1404 male workers from the Valparaíso and Metropolitan regions of Chile were measured in 2016. The sample was grouped by level of education (primary, secondary, technical and university) and age (21-30, 31-40 and 41-50 years). Robust ANOVA and post-hoc analyses using a one-step modified M-estimation of location were conducted based on bootstrap resampling. Both body height and popliteal height increased from the older to the younger age cohort. The largest increase was from the 41-50 to the 21-30 group, with a 1.1% increase in body height and 1.7% increase in popliteal height. When educational level was introduced into the analysis there was a marked increase in both body height and popliteal height for each cohort, but only in primary- and secondary-educated workers. Despite showing an overall increase in body height and popliteal height, younger workers with the highest levels of education showed fewer differences between them than did older workers with less education. The differences were larger in the older than in the younger cohorts. Similarly, this trend was less clear in workers with higher levels of education (technical and university), probably because of a dilution effect caused by increased access to higher education by workers in the lower income quintiles.

Breast Cancer Detection: The Development and Pilot Study of a "Tactile Landscape" as a Standardized Testing Tool.

INTRODUCTION: There is still a need for competent breast lump detection palpation skills, especially in developing countries. Our goal is to design, develop, and establish a test to determine whether students can, by touch alone, identify and discriminate between a range of different simulated lesions at different adiposity levels. METHODS: Common lesions, breast cancers, and cysts were physically simulated and hidden in a test object referred to as the "tactile landscape" (TL). Ribs, intercostal muscle, and nodularity-normal anatomical features-increased their realistic complexity. Varying depths of features simulated varying degrees of adiposity. A testing protocol was created to determine the testee's ability to identify and discriminate different commonly occurring breast masses using palpation. Five experts (four breast surgeons and one general practitioner) and 20 inexperienced medical students were recruited and tested. Results were compared. RESULTS: The TL has been based on previously verified breast models and has softness similar to 53% of women's breasts and nodularity similar to 60% as assessed in a breast clinic by breast surgeons. The five experts indicated that the simulated lesions felt like those they might encounter in clinical practice and all of them identified the lesions and nonlesions hidden in the TL 100% correctly, thus indicating the value of the model. In contrast, only one student was able to identify all the lesions. One student identified none of them. The remaining students mean score was 65%. CONCLUSIONS: All students but one performed poorly in comparison to the experts. This indicates that the test could be useful to test students' ability to identify and discriminate breast masses. If successful, it will add previously missing capability to the mix of assessment instruments already used, thus potentially improving clinical breast examination training and assessment.

New horizons in design for autonomous ageing.

The world is ageing rapidly. Between 2000 and 2050, the number of people aged ≥65 will double as a proportion of the global population, from 7% to 16%, respectively. By 2050, for the first time in human history, there will be more older people than children (aged 0­14 years) in the population. More distinctive is the tremendous increase in the oldest old aged ≥85. This challenges society to adapt, in order to maximise the health and functional capacity of older people as well as their social participation and security. Ageing is a multidimensional process of change in the physical, mental and social domain, leading to functional decline. Design thinking has embraced ageing as a topic where it can add to public health interventions. Applications of design and technology can contribute to 'autonomous ageing', for example, independent living and life style support, and can compensate for functional deficits associated with ageing. The focus is on supporting and reinforcing the reduced physical, mental, social and functional capacities of older people by applying groundbreaking, innovative design inclusive engineering methods, always starting with a human-centered integrated approach. Examples of design for geriatric giants include design for falls prevention, dementia care and integrated care. The establishment of collaborative networks between clinicians and designers, academia and industry is required to advance design for autonomous ageing.

Hand supports to assist toilet use among the elderly.

Improving the toilet environment holds promises for increasing the quality of life for elderly and disabled persons. This is one of the goals of the Friendly Rest Room (FRR) project. The study described in this article explored the preference and use of supports in the toilet environment during the entire toilet ritual. An adjustable test frame was built with a toilet and three types of supports. Fourteen subjects were asked which positions they favoured for each support. After using all three supports, they were asked which support they found most comfortable. In general, the preferred positions depended on personal preferences more than on dimensions of the body. It was concluded that there is a preference for vertical supports for sitting down and standing up. During toilet use the side supports were equally appreciated.

Anthropometry of a friendly rest room.

The use of common anthropometric tables often is not of any help when designing them for disabled people. This article addresses the advantage of first doing an observational study on the use of similar aids by disabled people. From that study, the relevant variables and critical areas can be learned. When users participate in the design process, the newly developed item probably will be innovative in comparison to just a desk research and development project. This means that a large sample is not necessary to find the potential for improvement. The study also delivers a better understanding of the fit of a particular product. This article discusses tools in anthropometry can help the designer understand the relation between dimensions and decide what should be adjustable and what should be fixed or produced in different sizes.