The TACOs (time-based assessment computerized strategy) approach to evaluating occupational working postures.

Many investigations of biomechanical overload concentrate on upper limbs and manual handling: certain jobs require an evaluation on spinal and lower limb postures. While existing methodologies adequately describe postures, they often poorly consider the organisation. This shortcoming prompted the development of TACOs for spinal and lower limb postures, using organisational factors to adjust the risk indexes. The TACOs is set out in steps: task identification, posture assessment, duration, and a final evaluation also for complex cycles. Given the complexity, tools have been devised, free downloadable, to facilitate evaluation. Studies on the TACOs reliability indicate excellent intra-observer and moderate interobserver agreement. TACOs, defining the task as a measurement unit, offers the advantage of assessing postures more easily and, considering duration, provides precise evaluation of the final risk. While the method does not demonstrate predictive validity regarding related diseases, it nonetheless enables the classification of exposure levels, even in complex multitask scenarios.

The development of TACOs strategy for posture analysis stems from the need to modulate the intensity of posture risk factors in relation with duration. It estimates final exposure scores in real work through detailed preliminary organisational studies. This involves identifying tasks, assessing postures for type and duration in work period.

Latin Questionnaire: a threshold strategy for anamnestic screening of occupational musculoskeletal disorders through specific reference groups.

Introduction: Health surveillance programs conducted for both individual workers and working populations as a whole are managed by occupational health physicians and focus on disorders and diseases caused by biomechanical overload, primarily for preventive purposes. Objectives: The purpose of the paper is to update an anamnestic protocol for studying musculoskeletal disorders after more than 40 years experience of its application. The updated version has been re-named the Latin Questionnaire. The protocol enables preliminary epidemiological evaluation, by comparing results of exposed populations to those from a reference population, thanks to the introduction of a severity threshold, a concept lacking in similar questionnaires. Methods: The Latin Questionnaire is based on symptoms of discomfort, pain, and paraesthesia. Each symptom is described in terms of location, duration, number of episodes, irradiation, and treatment. The model covers present symptoms during the previous 12 months and is designed to identify positive anamnestic cases (when positive according to the threshold), cases with minor disorders, and negative cases for conditions involving the spine and upper and lower limbs. Results: The updated anamnestic model was validated again through the collaborative effort involving 37 physicians from 14 Latin countries. To enable comparisons with exposed populations, an updated reference population (4,000 unexposed workers) is presented, evaluating the percentages of subjects positive according to thresholds for spine and upper and lower limbs and the incidence of acute lower back pain, broken down by gender and age groups. Examples of application of the questionnaire are also presented. Conclusions: The Latin Questionnaire, which has also been implemented in digital form (free download), allows selection of significant anamnestic cases compared to cases with minor disorders. This strategy is indispensable for correctly conducting preliminary epidemiological studies. Example applications confirm the presence of significant differences between the percentages of subjects with positive thresholds in exposed compared to reference groups, with surpluses proportional to their levels of biomechanical overload.

Understanding outcome metrics of the revised NIOSH lifting equation.

The interpretation of the calculated result of the revised NIOSH Lifting Equation (RNLE) has been problematic because the relationship of the calculated result to back injury risk has not always been either well understood nor consistently interpreted. During the revision of the ISO standard 11228-1 (Manual lifting, lowering and carrying), an extensive literature review was conducted on validation studies of the RNLE. A systematic review of exposure-risk associations between the LI metrics and various low-back health outcomes from peer-reviewed epidemiological studies was conducted. Risk interpretations for different levels of calculated result of the RNLE are added to the ISO standard. Rationale for the risk interpretations is presented in this paper.

Scientific basis of the OCRA method for risk assessment of biomechanical overload of upper limb, as preferred method in ISO standards on biomechanical risk factors.

We are writing in regards to Armstrong et al`s recent discussion paper (1), which addresses the scientific basis of ISO standards on biomechanical risk factors and more specifically the OCRA methodology. The paper comments on the ISO's working methods, but it will be up to the ISO to respond if it sees fit to do so. As the authors of the OCRA method, we wish to respond in a individual capacity. For several years, we have belonged to an ISO working group (ISO TC 159/SC3/WG4) advocating methods for the assessment of biomechanical overload risk; the members of the working group come from various countries and represent public authorities, social partners and researchers with particular expertise in this field. Our decision to send this letter to the editor was motivated by the following position put forth in Armstrong et al`s paper concerning the rigor of development of the ISO ergonomics standards: "The production of the ISO ergonomics standards differed substantially from the writing of evidence-based practical guidelines. According to the limited information provided in the published documents, the ISO ergonomics standards were not based on a systematic search and appraisal of available literature. It is not clear why the ISO subcommittee preferred one method of risk assessment over others. For instance, the ISO 11228-3 identified three detailed risk assessment methods for repetitive hand exertions at high frequency: OCRA (a concise index for the assessment of exposure to repetitive movements of the upper limbs) (20), ACGIH hand activity level (HAL) (21), and the Strain Index (22), but preferred the OCRA methods without providing a scientific basis or comparison (eg, intra- and inter-observer reliability, strength of association with musculoskeletal disorders (MSD), etc.) even though such comparisons are available in the literature (13, 23). As a result, some statements in ISO 11228-3 appear to be based on personal opinions and are in contrast with scientific evidence from the literature. For instance, the ISO standard includes a statement "in many epidemiological surveys it (OCRA) has shown itself to be well related with health effects (such as the occurrence of UL-WMSD [upper limb-work related MSD)]" (13). This statement was not supported by a well-designed epidemiological study in 2007 when the ISO standard was published (19). Indeed, in 2010, Takala and colleagues noted the absence of longitudinal studies on the association between the OCRA index and the risk of MSD. They also pointed out the absence of studies on the repeatability of the OCRA method (13)". (Note: the references in italic relate to the original paper). We would like to point out that the ISO standards in question (2) were actually developed by the working group, as mandated by ISO, over the period 2000‒2004.The years leading up to the publication of the standard (2005‒2007) were dedicated to the challenging task of democratically seeking the endorsement of the ISO member countries. During this time, no significant changes could be made to the basic text other than those arising from specific observations or comments from the countries. This needs to be taken into account, especially when debating the references underpinning the standard. More specifically, the standard in question (ISO 11228-3) (2) in Annex A, clearly states that the general reference model for assessing "repetitive, high frequency, low load movements of the upper limbs" is a Consensus Document, drafted and published in 2001 by the IEA-Technical Committee on Musculoskeletal Disorders, with the endorsement of the International Commission on Occupational Health (ICOH) (3). The study considered at least 14 different methods that have over time been suggested in the literature as briefly summarized in the same ISO standard (2). The recommendations set forth in this vital Consensus Document went on to become the basis for choosing the most appropriate methods to suggest to future users through the standard (OCRA; ACGIH Hand Activity Level (HAL); Strain Index), each with their respective merits and limits in compliance with the criteria set out in the Consensus Document and taking into account their applicability in the field and ability to interpret the results of the risk assessment. It is against this background, and in light of the rationale described in Annex A, that the entire group agreed that the OCRA method was to be considered as the "preferred" method, insofar as it was deemed to best match the recommendations laid out in the aforementioned Consensus Document. Furthermore the OCRA method was, at the time, the only risk assessment method supported by the results of several epidemiological, albeit cross-sectional studies, uniquely available in literature. The study was based on a very large number of cases (>5000 cases) with results both of risk evaluation of upper-limb biomechanical overload (using the OCRA method) and of musculo-skeletal clinical examination (assessing the corresponding diseases). Such studies were reported in a special issue of Ergonomics (4), in an updated paper ‒ first published in Italian (5) ‒ also in Ergonomics (6), in the books edited by Elsevier (7), and CRC Taylor & Francis (8). This risk/damage database enabled an estimation (within defined limits) of the risk of upper-limb work-related musculoskeletal disorders at a given OCRA index level. Starting from the established relation among risk indexes and percent of pathological subjects, it was possible to determine the risk limit values provided by the ISO standard (2). With reference to the alleged absence of studies on the repeatability of the OCRA method, we prefer to mention the most recent results obtained by other researchers, rather than our findings, acknowledging the good "inter-rater reliability" of the OCRA Checklist, and stating that "the OCRA Checklist inter-rater reliability scores were among the highest reported in the literature for semi-quantitative physical exposure assessment tools of the upper extremity" (9) As for the scientific base, we suggest Armstrong et al (1) could get more valuable information about the OCRA methodology looking not only to the 1996 special issue in Italian language (10) ‒ the only publication they mention dealing specifically with OCRA ‒ but to the many updated publications. Some of the most relevant publications in English (as suggested by the publisher) are mentioned in the references here below. Many other publications and manuals in English, Italian, Spanish and Portuguese are available but not reported here due to limitation of space. A complete list of our publications can be found on our website: www.epmresearch.org, where some of the articles are available for download. Simple tools (Excel spreadsheets) for carrying out risk assessments by OCRA can also be freely downloaded from the same website. The validity and usability of OCRA methodology can also be indirectly confirmed by its extensive use around the world. For example, a recent search on ScienceDirect (www.sciencedirect.com/science/journals/all/full-text-access) has recently shown that more than 477 works dealing with OCRA hae been published by different authors in indexed journals to date. In conclusion, we recommend the authors of the discussion paper (1) deepen their analysis of the OCRA methodology [beyond the only cited old 1996 paper (10)] before expressing definite conclusions about the scientific value of the OCRA methodology and about the entire ISO standard-setting system. Our team is always happy to engage with the scientific community and end users of studies on biomechanical overload, as we have also done within the ISO for many years now. ISO working groups arguably offer valuable opportunities to come together at the international level and table discussions between researchers and users. We are researchers who have devoted our life's work to prevention, and intend to continue striving towards that goal, with everyone's help and without bickering, bias, vested interests, or professional rivalry. The health and well-being of workers is all we have ever cared about. We have always been ready to cooperate with those who share this vital objective. References 1. Armstrong T J, Burdorf I A, Descatha A, Farioli A, Graf M, Horie S, Marras W S, Potvin J R, Rempel D, Spatari G, Takala E P, Verbeek J, Violante FS. Scientific basis of ISO standards on biomechanical risk factors. Scand J Work Environ Health ‒ online first. https://doi.org/10.5271/sjweh.3718 2. ISO. ISO 11228-3. Ergonomics - Manual handling - Handling of low loads at high frequency. ISO, 2007. Geneva, Switzerland. 3. Colombini D, Occhipinti E, Delleman D, Fallentin N, Kilbom A, Grieco A. Exposure assessment of upper limb repetitive movements: a consensus document in W. Karwowski International Encyclopaedia of Ergonomics and Human Factors, New York: Taylor & Francis, 2001. 4. Colombini D, Grieco A, Occhipinti E. Occupational musculoskeletal disorders of the upper limbs due to mechanical overload. Ergonomics. Special issue;1998:41(9). 5. Occhipinti, E., Colombini, D. Metodo OCRA: aggiornamento dei valori di riferimento e dei modelli di previsione dell'occorrenza di UL-WMSDs nelle popolazioni lavorative esposte a movimenti e sforzi ripetuti degli arti superiori. [The OCRA method: update of UL-WMSDs reference values and prediction models of occurrence in working populations exposed to repetitive movements and strains of the upper limbs]. La Medicina del Lavoro, 2004. 95;4:305-319 6. Occhipinti E, Colombini D. Updating reference values and predictive models of the OCRA method in the risk assessment of work-related musculoskeletal disorders of the upper limbs. Ergonomics; 2007,50(11):1727-1739. https://doi.org/10.1080/00140130701674331 7. Colombini D, Occhipinti E, Grieco A. Risk assessment and management ofrepetitive movements and exertions of upper limbs. Amsterdam: Elsevier Science, 2002. 8. Colombini D, Occhipinti E. Risk analysis and management of repetitive actions: a guide for applying the OCRA system (occupational repetitive actions). New York: CRC press, 2016. 9. Paulsen R, Gallu T, Gilkey D, Reiser R, Murgia L, Rosecrance J. The inter-rater reliability of Strain Index and OCRA Checklist task assessments in cheese processing. Applied Ergonomics. 2015;51,199-204. https://doi.org/10.1016/j.apergo.2015.04.019 10. Occhipinti E, Colombini D. Proposal of a concise index for the evaluation of the exposure to repetitive movements of the upper extremity (OCRA index)]. Med Lav. Special issue, 1996 Nov-Dec; 87(6): 526-548.

Variable Lifting Index (VLI): A New Method for Evaluating Variable Lifting Tasks.

OBJECTIVE: We seek to develop a new approach for analyzing the physical demands of highly variable lifting tasks through an adaptation of the Revised NIOSH (National Institute for Occupational Safety and Health) Lifting Equation (RNLE) into a Variable Lifting Index (VLI). BACKGROUND: There are many jobs that contain individual lifts that vary from lift to lift due to the task requirements. The NIOSH Lifting Equation is not suitable in its present form to analyze variable lifting tasks. METHOD: In extending the prior work on the VLI, two procedures are presented to allow users to analyze variable lifting tasks. One approach involves the sampling of lifting tasks performed by a worker over a shift and the calculation of the Frequency Independent Lift Index (FILI) for each sampled lift and the aggregation of the FILI values into six categories. The Composite Lift Index (CLI) equation is used with lifting index (LI) category frequency data to calculate the VLI. The second approach employs a detailed systematic collection of lifting task data from production and/or organizational sources. The data are organized into simplified task parameter categories and further aggregated into six FILI categories, which also use the CLI equation to calculate the VLI. RESULTS: The two procedures will allow practitioners to systematically employ the VLI method to a variety of work situations where highly variable lifting tasks are performed. CONCLUSIONS: The scientific basis for the VLI procedure is similar to that for the CLI originally presented by NIOSH; however, the VLI method remains to be validated. APPLICATION: The VLI method allows an analyst to assess highly variable manual lifting jobs in which the task characteristics vary from lift to lift during a shift.

IEA/WHO toolkit for WMSDs prevention: criteria and practical tools for a step by step approach.

When studying WMSDs, several determinants and their interrelationship are considered as relevant. Hence the necessity of an "holistic" approach to prevention, especially when preparing technical rules and strategic plans. There is a strong request, from OSH agencies and operators, for developing "simple" tools for risk assessment and management. In this context WHO asked IEA to develop a "Toolkit for WMSD prevention". The paper presents one of the main contribution to this WHO project, focused on selecting tools at different level for hazard identification, risk estimation and management. Proposals are based on two essential criteria: Acting on a step-by-step approach; Taking into account the presence of multiple influencing factors. The proposals consider: A Basic Step devoted to hazard identification by operative "key-enter" questions, that can be operated also by non-experts. A First Step, (quick assessment), for identifying 3 possible conditions: acceptable; high risk present; more detailed analysis (via tools presented at second step) necessary. This step can be operated by non-experts with only some specific training. A Second Step, where recognized (i.e. from international standards or guidelines) tools for risk estimation are used. This step can be operated only by persons with some specific training.

Hazard identification and pre-map with a simple specific tool: synthesis of application experience in handicrafts in various productive sectors.

In August 2009, an international group was founded with the task of developing a "toolkit for MSD prevention" under the IEA and in collaboration with the World Health Organization.According to the ISO standard 11228 series and the new Draft ISO TR 12259 "Application document guides for the potential user", our group developed a preliminary "mapping" methodology of occupational hazards in the craft industry, supported by software (Excel®, free download on: www.epmresearch.org).The possible users of toolkits are: members of health and safety committees; health and safety representatives; line supervisors; foremen; workers; government representatives; health workers providing basic occupational health services; occupational health and safety specialists.The proposed methodology, using specific key enters and quick assessment criteria, allows a simple ergonomics hazards identification and risk estimation to be made. It is thus possible to decide for which occupational hazards a more exhaustive risk assessment will be necessary and which occupational consultant should be involved (occupational physician, safety engineer, industrial hygienist, etc.).The methodology has been applied in different situations of small and medium craftsmanship Italian enterprises: leather goods, food, technical dental work, production of artistic ceramics and stained glass, beekeeping activities. The results are synthetically reported and discussed in this paper.

Preventing upper limb work-related musculoskeletal disorders (UL-WMSDS): new approaches in job (re)design and current trends in standardization.

In industrialized countries, upper limb work-related musculoskeletal disorders (UL-WMSDs) are the most common form of occupational diseases. They are generating a growing population of workers with reduced working capacity. The link between these pathologies and different aspects of work organization has been convincingly proven. Recent experiences in Europe supporting the combination of traditional work design methods used in manufacturing companies with ergonomics methods are reported briefly, with special focus on the use of the occupational repetitive action (OCRA) method for risk assessment and management of manual repetitive tasks. The combined approach strives to achieve the goal of maintaining a satisfactory level of productivity while respecting ergonomics criteria and, definitely, workers' health. New ergonomics standards provide for interaction between job and machinery designers and ergonomists in the design of work processes and workplaces. These standards generally refer only to the healthy adult working population and do not always provide criteria for protecting particular working populations, such as that represented by workers affected by UL-WMSDs. The results of preliminary studies concerning productive re-employment of workers with UL-WMSDs allow the introduction of some criteria for implementing current ergonomics standards in this connection. One aim of this paper is to summarize experiences of close cooperation between ergonomists, machinery designers and job designers to guarantee productivity and the prevention of musculoskeletal disorders. A second aim is to examine current ergonomics standards in the field of manual physical work (designed for healthy workers) and to suggest preliminary criteria for their implementation taking into account the capabilities and needs of specific sub-groups of the working population.