Productivity in older versus younger workers: A systematic literature review.

BACKGROUND: Worldwide ageing and thus, workforce ageing, is a concern for both developed and developing nations. OBJECTIVE: The aim of the current research was to determine, through a systematic literature review, the effects of age in three dimensions that are often used to define or assess productivity at work. METHODS: PICO framework was used to generate search strategies, inclusion criteria and terms. Scopus and PubMed databases were used. Peer-reviewed journal papers written in English and published (or in press) between January 2014 and December 2018 were included. RESULTS: After filtering through inclusion criteria, 74 papers were included in the review. Considering productivity, 41%of the findings showed no differences between younger and older workers, 31%report better productivity of younger workers and 28%reported that older workers had better productivity than younger workers. Performance was better in older workers (58%), presenteeism generally showed no significant differences between age groups (61%). Absenteeism was the only outcome where younger workers outperformed older workers (43%). CONCLUSION: Overall, there was no difference in productivity between older and younger workers. Older workers performed better than younger workers, but had more absenteeism, while presenteeism showed no differences. As ageing has come to workplaces, holistic approaches addressing total health are suggested to overcome the worldwide workforce ageing phenomenon.

Secular changes in the anthropometrics of Chilean workers and its implication in design.

BACKGROUND: Anthropometrics is very important when ensuring a physical match between end users and product or workstations. OBJECTIVES: The purpose of this study are twofold, to provide anthropometric data for the design of products and to examine the secular changes in the adult Chilean workers in a period of more than 20 years. METHODS: Nineteen anthropometric measurements from two samples from 1995 and 2016 were compared using independent t-test (95% confidence interval), where additionally absolute and relative differences were calculated. RESULTS: The secular trend observed for Stature is characterized by an increase average of 20mm and 10.5mm per decade for females and males, respectively. There is a positive secular trend for both genders, which is observed for most of the selected body measurements. The most pronounced increases were onWeight, Shoulder breadth, Body mass index, Popliteal height; Buttock-popliteal length and Hip width. CONCLUSIONS: Segmental dimensions that experienced a positive secular trend, together with Weight and Stature, are highly correlated with seating design, addressing the need to review products targeting Chilean adult workers, such as public transport seats, office furniture or industrial workplaces.

Are interventions effective at improving driving in older drivers?: A systematic review.

BACKGROUND: With the aging of the population, the number of older drivers is on the rise. This poses significant challenges for public health initiatives, as older drivers have a relatively higher risk for collisions. While many studies focus on developing screening tools to identify medically at-risk drivers, little research has been done to develop training programs or interventions to promote, maintain or enhance driving-related abilities among healthy individuals. The purpose of this systematic review is to synopsize the current literature on interventions that are tailored to improve driving in older healthy individuals by working on components of safe driving such as: self-awareness, knowledge, behaviour, skills and/or reducing crash/collision rates in healthy older drivers. METHODS: Relevant databases such as Scopus and PubMed databases were selected and searched for primary articles published in between January 2007 and December 2017. Articles were identified using MeSH search terms: ("safety" OR "education" OR "training" OR "driving" OR "simulator" OR "program" OR "countermeasures") AND ("older drivers" OR "senior drivers" OR "aged drivers" OR "elderly drivers"). All retrieved abstracts were reviewed, and full texts printed if deemed relevant. RESULTS: Twenty-five (25) articles were classified according to: 1) Classroom settings; 2) Computer-based training for cognitive or visual processing; 3) Physical training; 4) In-simulator training; 5) On-road training; and 6) Mixed interventions. Results show that different types of approaches have been successful in improving specific driving skills and/or behaviours. However, there are clear discrepancies on how driving performance/behaviours are evaluated between studies, both in terms of methods or dependent variables, it is therefore difficult to make direct comparisons between these studies. CONCLUSIONS: This review identified strong study projects, effective at improving older drivers' performance and thus allowed to highlight potential interventions that can be used to maintain or improve older drivers' safety behind the wheel. There is a need to further test these interventions by combining them and determining their effectiveness at improving driving performance.

Anthropometric characteristics of Chilean workers for ergonomic and design purposes.

Obtaining an appropriate match between a product and its end-users requires anthropometric data, which are typically outdated and show variations among different countries. Chile had its anthropometric data taken nearly 20 years ago, thus they are probably outdated. The purpose of this article is to describe some anthropometric characteristics of Chilean workers. An anthropometric survey involving 27 measures and five calculated body dimensions was conducted in 2016. The measurements were based on ISO 7250 and ISO 15535 to ensure the highest standards possible, and a total of 2946 workers, aged from 18 to 76 years old, participated in the survey. The results showed that Chilean workers have smaller dimensions than Dutch and US workers but have larger dimensions than South Koreans. The data presented in this article constitute the most up-to-date anthropometric dataset describing the dimensions of Chilean workers. Practitioner Summary: In Chile, women are smaller and weigh less than men, and both of these populations have high body mass index (BMIs). In addition, the Chilean population exhibits substantial differences compared with other international adult populations. The data presented in this article should be used as a reference when designing for Chilean workers.

A literature review of anthropometric studies of school students for ergonomics purposes: Are accuracy, precision and reliability being considered?

BACKGROUND: Despite offering many benefits, direct manual anthropometric measurement method can be problematic due to their vulnerability to measurement errors. OBJECTIVE: The purpose of this literature review was to determine, whether or not the currently published anthropometric studies of school children, related to ergonomics, mentioned or evaluated the variables precision, reliability or accuracy in the direct manual measurement method. METHODS: Two bibliographic databases, and the bibliographic references of all the selected papers were used for finding relevant published papers in the fields considered in this study. RESULTS: Forty-six (46) studies met the criteria previously defined for this literature review. However, only ten (10) studies mentioned at least one of the analyzed variables, and none has evaluated all of them. Only reliability was assessed by three papers. Moreover, in what regards the factors that affect precision, reliability and accuracy, the reviewed papers presented large differences. This was particularly clear in the instruments used for the measurements, which were not consistent throughout the studies. Additionally, it was also clear that there was a lack of information regarding the evaluators' training and procedures for anthropometric data collection, which are assumed to be the most important issues that affect precision, reliability and accuracy. CONCLUSIONS: Based on the review of the literature, it was possible to conclude that the considered anthropometric studies had not focused their attention to the analysis of precision, reliability and accuracy of the manual measurement methods. Hence, and with the aim of avoiding measurement errors and misleading data, anthropometric studies should put more efforts and care on testing measurement error and defining the procedures used to collect anthropometric data.

The influence of school furniture on students' performance and physical responses: results of a systematic review.

The purpose of this study was to determine, using a systematic review, whether the design and/or dimensions of school furniture affect the students' physical responses and/or their performance. Of the review studies, 64% presented positive results, i.e. proven effects; 24% presented negative effects or no change/effect; and the remaining 12% showed an unclear effect. The compatibility between school furniture dimensions and students' anthropometric characteristics was identified as a key factor for improving some students' physical responses. Design characteristics such as high furniture, sit-stand furniture, and tilt tables and seats also present positive effects. Finally, we concluded that further research should be conducted exploring various aspects of those variables, particularly focusing on more objective measures complemented by controlled and prospective design. Practitioner Summary: A systematic review of the literature presents a clearly positive effect of school furniture dimensions on students' performance and physical responses. Similar results appeared when school furniture design was tested. However, studying the effects of design and dimensions together produced an unclear positive effect.

The effect of secular trends in the classroom furniture mismatch: support for continuous update of school furniture standards.

In order to create safer schools, the Chilean authorities published a Standard regarding school furniture dimensions. The aims of this study are twofold: to verify the existence of positive secular trend within the Chilean student population and to evaluate the potential mismatch between the anthropometric characteristics and the school furniture dimensions defined by the mentioned standard. The sample consists of 3078 subjects. Eight anthropometric measures were gathered, together with six furniture dimensions from the mentioned standard. There is an average increase for some dimensions within the Chilean student population over the past two decades. Accordingly, almost 18% of the students will find the seat height to be too high. Seat depth will be considered as being too shallow for 42.8% of the students. It can be concluded that the Chilean student population has increased in stature, which supports the need to revise and update the data from the mentioned Standard. PRACTITIONER SUMMARY: Positive secular trend resulted in high levels of mismatch if furniture is selected according to the current Chilean Standard which uses data collected more than 20 years ago. This study shows that school furniture standards need to be updated over time.

Analysis of the most relevant anthropometric dimensions for school furniture selection based on a study with students from one Chilean region.

Most of the worldwide standards used for furniture selection suggest the use of the Stature of the school children, assuming that all the other anthropometric characteristics will also be appropriate. However, it is important to consider that students' growth differ with age. The aim of this study is to determine if Popliteal Height can be used as a better, or more adequate, measure for classroom furniture selection when comparing with Stature. This study involved a representative group of 3046 students from the Valparaíso Region, in Chile. Regarding the methodology, eight anthropometric measures were gathered, as well as six furniture dimensions from the Chilean standard. After assigning the level of school furniture using Stature and Popliteal Height to each of the students, six mismatch equations were applied. The results show that when using Popliteal Height, higher levels of match were obtained for the two more important furniture dimensions. Additionally, it also presents a better cumulative fit than Stature. In conclusion, it seems that Popliteal Height can be the most accurate anthropometric measure for classroom furniture selection purposes.

Evaluation of the match between anthropometric measures and school furniture dimensions in Chile.

BACKGROUND: Students are exposed to the first systematic tasks or activities that a human being carries out in his/her life while at school. In this workplace situation, school furniture is a key factor for the adoption of proper body posture. OBJECTIVE: The aim of this paper was to observe and determine the potential mismatch between school furniture dimensions and anthropometric characteristics of the students from the Valparaíso region of Chile. METHODS: The sample consisted of 3,078 volunteer participants from 18 schools (public, semi-public, private). Eight anthropometric measures were gathered, together with six furniture dimensions. Mismatch analyses were carried out by using pre-defined mismatch criteria. RESULTS: Many different types of school furniture were presented at the schools. Also, a high level of mismatch was registered for seat height, desk height and seat-to-desk clearance. Finally, the analysis of all considered dimensions together showed that there was a high level of cumulative mismatch. CONCLUSIONS: It can be concluded that there were high levels of mismatch between the school furniture and student anthropometric characteristics and that this mismatch varied within the difference types of schools. This situation may have occurred because furniture acquisition was made without considering any ergonomic criteria.

Applying different equations to evaluate the level of mismatch between students and school furniture.

The mismatch between students and school furniture is likely to result in a number of negative effects, such as uncomfortable body posture, pain, and ultimately, it may also affect the learning process. This study's main aim is to review the literature describing the criteria equations for defining the mismatch between students and school furniture, to apply these equations to a specific sample and, based on the results, to propose a methodology to evaluate school furniture suitability. The literature review comprises one publications database, which was used to identify the studies carried out in the field of the abovementioned mismatch. The sample used for testing the different equations was composed of 2261 volunteer subjects from 14 schools. Fifteen studies were found to meet the criteria of this review and 21 equations to test 6 furniture dimensions were identified. Regarding seat height, there are considerable differences between the two most frequently used equations. Although seat to desk clearance was evaluated by knee height, this condition seems to be based on the false assumption that students are sitting on a chair with a proper seat height. Finally, the proposed methodology for suitability evaluation of school furniture should allow for a more reliable analysis of school furniture.

Testing thermal comfort of trekking boots: an objective and subjective evaluation.

The study of the thermal comfort of the feet when using a specific type of shoe is of paramount importance, in particular if the main goal of the study is to attend to the needs of users. The main aim of this study was to propose a test battery for thermal comfort analysis and to apply it to the analysis of trekking boots. Methodologically, the project involves both objective and subjective evaluations. An objective evaluation of the thermal properties of the fabrics used in the boots was developed and applied. In addition, the thermal comfort provided when using the boots was also assessed both subjective and objectively. The evaluation of the thermal comfort during use, which was simulated in a laboratory environment, included the measurement of the temperature and moisture of the feet. The subjective assessment was performed using a questionnaire. From the results obtained, it was possible to define an optimal combination of fabrics to apply to trekking boots by considering the provided thermal insulation, air permeability and wicking. The results also revealed that the subjective perception of thermal comfort appears to be more related to the increase in temperature of the feet than to the moisture retention inside the boot. Although the evaluation of knits used in the boots indicated that a particular combination of fibres was optimal for use in the inner layer, the subjective and objective evaluation of thermal comfort revealed that the evaluation provided by users did not necessarily match the technical assessment data. No correlation was observed between the general comfort and specific thermal comfort assessments. Finally, the identification of thermal discomfort by specific foot areas would be useful in the process of designing and developing boots.

From ergonomics to design specifications: contributions to the design of a processing machine in a tire company.

The development of ergonomics' recommendations, guidelines and standards are attempts to promote the integration of ergonomics into industrial contexts. Such developments result from several sources and professionals and represent the effort that has been done to develop healthier and safer work environments. However, the availability of large amount of data and documents regarding ergonomics does not guarantee their applicability. The main goal of this paper is to use a specific case to demonstrate how ergonomics criteria were developed in order to contribute to the design of workplaces. Based on the obtained results from research undertaken in a tire company, it was observed that the ergonomics criteria should be presented as design specifications in order to be used by engineers and designers. In conclusion, it is observed that the multiple constraint environment impeded the appliance of the ergonomics criteria. It was also observed that the knowledge on technical design and the acquaintance with ergonomic standards, the level of integration in the design team, and the ability to communicate with workers and other technical staff have paramount importance in integrating ergonomics criteria into the design process.

Ergonomic tridimensional analysis: critical ergonomic factors identification in a commercial environmental.

The Ergonomic tridimensional analysis (ETdA) was developed to be used as an auxiliary tool on the ergonomic intervention. It was specially designed for commercial areas with free circulation of people. Due to that, the client, the third ETdA dimension, becomes an important element and their opinions relevant in the ergonomic analysis. The remains two ETdA dimensions, professionals and analyst, play an identical role as in the traditional occupational ergonomic analysis. For each of these dimensions, specific observation tools were assembled: an ETdA questionnaire, an evaluation form and a checklist for direct and indirect observations. The variables that allow the ETdA operability are identified as Ergonomic Factors (EFs). A case study is presented identifying, for each dimension, the critical EFs. This will allow the design of the weighting table, where the influence of each dimensions results is measured, stressing the important role of clients on ergonomic issues.

Mismatch between classroom furniture and anthropometric measures in Chilean schools.

Children spend about five hours per day sitting down while doing their school work. Considering this as well as the potential inadequate use of school furniture, it is likely that some anatomical-functional changes and problems in the learning process may occur. The aim of this study was to compare furniture sizes within three different schools with the anthropometric characteristics of Chilean students in the Valparaíso region, in order to evaluate the potential mismatch between them. The sample consisted of 195 volunteer students (94 male, 101 female) of the 8th grade, ranging from 12.5 to 14.5 years of age from 3 different schools. Regarding the methodology, 6 anthropometric measures (Stature, Popliteal height, Buttock-popliteal length, Elbow height while sitting, Hip width, Thigh thickness and Subscapular height) were gathered, as well as 8 dimensions from the school furniture. For the evaluation of classroom furniture a match criterion equation was defined. After considering the existing classroom furniture dimensions in each match criterion equation, the anthropometric characteristics of the considered population were compared in order to determine the mismatch between them. Results indicated that seat height, which should be considered as the starting point for the design of classroom furniture, was appropriate for students' popliteal height in only 14% of the 2 out of the 3 schools, and 28% in the third. Seat to desk height was too high and mismatched 99% of the students in one school and 100% in the others. Therefore, it was possible to conclude that the classroom's furniture was inadequate in almost all the analyzed cases and subjects. It is possible that the high mismatch percentage found between furniture and students' anthropometry can be associated to the fact that the acquisition and selection of the furniture was made without any ergonomic concern or criteria.

Hearing protectors acceptability in noisy environments.

OBJECTIVES: Although hearing protectors must be used as a temporary solution, their choice should take into account several aspects, such as ergonomic features, associated with this device. The present study aims to analyse the relationship between the acoustical attenuation efficiency and other aspects related to the comfort afforded by hearing protectors and, consequently, their acceptability when used in industrial noisy environments. METHODS: An evaluation of comfort was performed using a questionnaire, completed by 20 workers. Several scales related to the subjective feeling of comfort were used to quantify the comfort index of a given protector. Simultaneously, the time of usage of each protector was self-recorded by each subject. To test the relationship between the comfort index and the time during which protectors were used, a two-way analysis of variance (two-way ANOVA) was applied. RESULTS AND CONCLUSIONS: The results obtained seem to demonstrate that there are significant differences between catalogued and effective attenuation. Protectors with less catalogued attenuation, but with higher acceptability, i.e. which were more comfortable, tended to be more efficient than protectors with a higher catalogued attenuation, but which were less comfortable. Finally, it must be emphasized that high efficiency can only be achieved through the attainment of an adequate balance between the range of parameters likely to determine its usage.