Epidemiological Differences Between Localized and Nonlocalized Low Back Pain.

STUDY DESIGN: A cross-sectional survey with a longitudinal follow-up. OBJECTIVES: The aim of this study was to test the hypothesis that pain, which is localized to the low back, differs epidemiologically from that which occurs simultaneously or close in time to pain at other anatomical sites SUMMARY OF BACKGROUND DATA.: Low back pain (LBP) often occurs in combination with other regional pain, with which it shares similar psychological and psychosocial risk factors. However, few previous epidemiological studies of LBP have distinguished pain that is confined to the low back from that which occurs as part of a wider distribution of pain. METHODS: We analyzed data from CUPID, a cohort study that used baseline and follow-up questionnaires to collect information about musculoskeletal pain, associated disability, and potential risk factors, in 47 occupational groups (office workers, nurses, and others) from 18 countries. RESULTS: Among 12,197 subjects at baseline, 609 (4.9%) reported localized LBP in the past month, and 3820 (31.3%) nonlocalized LBP. Nonlocalized LBP was more frequently associated with sciatica in the past month (48.1% vs. 30.0% of cases), occurred on more days in the past month and past year, was more often disabling for everyday activities (64.1% vs. 47.3% of cases), and had more frequently led to medical consultation and sickness absence from work. It was also more often persistent when participants were followed up after a mean of 14 months (65.6% vs. 54.1% of cases). In adjusted Poisson regression analyses, nonlocalized LBP was differentially associated with risk factors, particularly female sex, older age, and somatizing tendency. There were also marked differences in the relative prevalence of localized and nonlocalized LBP by occupational group. CONCLUSION: Future epidemiological studies should distinguish where possible between pain that is limited to the low back and LBP that occurs in association with pain at other anatomical locations. LEVEL OF EVIDENCE: 2.

Descriptive Epidemiology of Somatising Tendency: Findings from the CUPID Study.

Somatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20-59 from 46 occupational groups in 18 countries (response rate 70%). The seven symptoms were all mutually associated (odds ratios for pairwise associations 3.4 to 9.3), and each contributed to a measure of somatising tendency that exhibited an exposure-response relationship both with multi-site pain (prevalence rate ratios up to six), and also with sickness absence for non-musculoskeletal reasons. In most participants, the level of somatising tendency was little changed when reassessed after a mean interval of 14 months (75% having a change of 0 or 1 in their symptom count), although the specific symptoms reported at follow-up often differed from those at baseline. Somatising tendency was more common in women than men, especially at older ages, and varied markedly across the 46 occupational groups studied, with higher rates in South and Central America. It was weakly associated with smoking, but not with level of education. Our study supports the use of questions from the Brief Symptom Inventory as a method for measuring somatising tendency, and suggests that in adults of working age, it is a fairly stable trait.

Classification of neck/shoulder pain in epidemiological research: a comparison of personal and occupational characteristics, disability, and prognosis among 12,195 workers from 18 countries.

To inform case definition for neck/shoulder pain in epidemiological research, we compared levels of disability, patterns of association, and prognosis for pain that was limited to the neck or shoulders (LNSP) and more generalised musculoskeletal pain that involved the neck or shoulder(s) (GPNS). Baseline data on musculoskeletal pain, disability, and potential correlates were collected by questionnaire from 12,195 workers in 47 occupational groups (mostly office workers, nurses, and manual workers) in 18 countries (response rate = 70%). Continuing pain after a mean interval of 14 months was ascertained through a follow-up questionnaire in 9150 workers from 45 occupational groups. Associations with personal and occupational factors were assessed by Poisson regression and summarised by prevalence rate ratios (PRRs). The 1-month prevalence of GPNS at baseline was much greater than that of LNSP (35.1% vs 5.6%), and it tended to be more troublesome and disabling. Unlike LNSP, the prevalence of GPNS increased with age. Moreover, it showed significantly stronger associations with somatising tendency (PRR 1.6 vs 1.3) and poor mental health (PRR 1.3 vs 1.1); greater variation between the occupational groups studied (prevalence ranging from 0% to 67.6%) that correlated poorly with the variation in LNSP; and was more persistent at follow-up (72.1% vs 61.7%). Our findings highlight important epidemiological distinctions between subcategories of neck/shoulder pain. In future epidemiological research that bases case definitions on symptoms, it would be useful to distinguish pain that is localised to the neck or shoulder from more generalised pain that happens to involve the neck/shoulder region.

Patterns of multisite pain and associations with risk factors.

To explore definitions for multisite pain, and compare associations with risk factors for different patterns of musculoskeletal pain, we analysed cross-sectional data from the Cultural and Psychosocial Influences on Disability (CUPID) study. The study sample comprised 12,410 adults aged 20-59 years from 47 occupational groups in 18 countries. A standardised questionnaire was used to collect information about pain in the past month at each of 10 anatomical sites, and about potential risk factors. Associations with pain outcomes were assessed by Poisson regression, and characterised by prevalence rate ratios (PRRs). Extensive pain, affecting 6-10 anatomical sites, was reported much more frequently than would be expected if the occurrence of pain at each site were independent (674 participants vs 41.9 expected). In comparison with pain involving only 1-3 sites, it showed much stronger associations (relative to no pain) with risk factors such as female sex (PRR 1.6 vs 1.1), older age (PRR 2.6 vs 1.1), somatising tendency (PRR 4.6 vs 1.3), and exposure to multiple physically stressing occupational activities (PRR 5.0 vs 1.4). After adjustment for number of sites with pain, these risk factors showed no additional association with a distribution of pain that was widespread according to the frequently used American College of Rheumatology criteria. Our analysis supports the classification of pain at multiple anatomical sites simply by the number of sites affected, and suggests that extensive pain differs importantly in its associations with risk factors from pain that is limited to only a small number of anatomical sites.

Disabling musculoskeletal pain in working populations: is it the job, the person, or the culture?

To compare the prevalence of disabling low back pain (DLBP) and disabling wrist/hand pain (DWHP) among groups of workers carrying out similar physical activities in different cultural environments, and to explore explanations for observed differences, we conducted a cross-sectional survey in 18 countries. Standardised questionnaires were used to ascertain pain that interfered with everyday activities and exposure to possible risk factors in 12,426 participants from 47 occupational groups (mostly nurses and office workers). Associations with risk factors were assessed by Poisson regression. The 1-month prevalence of DLBP in nurses varied from 9.6% to 42.6%, and that of DWHP in office workers from 2.2% to 31.6%. Rates of disabling pain at the 2 anatomical sites covaried (r = 0.76), but DLBP tended to be relatively more common in nurses and DWHP in office workers. Established risk factors such as occupational physical activities, psychosocial aspects of work, and tendency to somatise were confirmed, and associations were found also with adverse health beliefs and group awareness of people outside work with musculoskeletal pain. However, after allowance for these risk factors, an up-to 8-fold difference in prevalence remained. Systems of compensation for work-related illness and financial support for health-related incapacity for work appeared to have little influence on the occurrence of symptoms. Our findings indicate large international variation in the prevalence of disabling forearm and back pain among occupational groups carrying out similar tasks, which is only partially explained by the personal and socioeconomic risk factors that were analysed.

Pedestrians' Beliefs about Road Crossing in Bogotá: Questionnaire Development / Puntos de Vista de peatones en un cruce de vías en Bogotá: desarrollo de cuestionario

Understanding the pedestrian choices is essential for the design of safe road systems. This study develops methods for self-reported assessment of pedestrian behavior. A self-report instrument was developed to investigate the Theory of Planned Behavior (TPB) constructs in relation to pedestrians' road crossing using a convenient sample. Internal consistency and factor analysis were conducted to test the reliability and construct validity of the instrument. Self-reported intention to execute risky behavior was compared with observed behaviors. The developed questionnaire showed high internal consistency for most of the TPB constructs (Chronbach's alpha>0.7). Factor analyses confirmed that questions grouped in constructs, as hypothesized. Pedestrians' intention to execute risky behavior was related to pedestrians' perceived physical capability and to the simultaneous crossing of other pedestrians. However, this intention correlated moderately with observed risky behavior (Rs = 0.35). The potential to understand the mechanisms of pedestrian choices using the developed instrument are considered exploratory, yet promising.

El poder entender las decisiones que toma un peatón es esencial para el diseño de sistemas viales seguros. Este estudio desarrolla métodos para la medición del comportamiento del peatón por medio de auto-reportes. Se desarrolló un instrumento de auto-reporte para investigar los constructos de la Teoría del Comportamiento Planeado (TPB, por sus siglas en inglés) en relación al cruce de las vías por parte de los peatones, usando una muestra conveniente. Se condujeron análisis de consistencia interna y de factores para probar la confiabilidad y validez de constructos del instrumento. La intención auto-reportada de ejecutar comportamientos riesgosos fue comparada con los comportamientos observados. El desarrollo del cuestionario mostró una alta consistencia interna para la mayoría de los constructos del TPB (alfa de Cronbach > 0.7). El análisis de factores confirmó que las preguntas se agrupaban en constructos, tal y como se hipotetizó; la intención de los peatones de ejecutar comportamientos riesgosos estuvo relacionada con la posibilidad física percibida por los peatones y con el cruce simultáneo de otros peatones. Sin embargo, esta intención se correlacionó solo moderadamente con el comportamiento riesgoso observado (Rs = 0.35). En conclusión, el potencial para entender los mecanismos de las elecciones de los peatones, usando el instrumento desarrollado, se considera aún exploratorio, pero sin embargo prometedor.

The CUPID (Cultural and Psychosocial Influences on Disability) study: methods of data collection and characteristics of study sample.

BACKGROUND: The CUPID (Cultural and Psychosocial Influences on Disability) study was established to explore the hypothesis that common musculoskeletal disorders (MSDs) and associated disability are importantly influenced by culturally determined health beliefs and expectations. This paper describes the methods of data collection and various characteristics of the study sample. METHODS/PRINCIPAL FINDINGS: A standardised questionnaire covering musculoskeletal symptoms, disability and potential risk factors, was used to collect information from 47 samples of nurses, office workers, and other (mostly manual) workers in 18 countries from six continents. In addition, local investigators provided data on economic aspects of employment for each occupational group. Participation exceeded 80% in 33 of the 47 occupational groups, and after pre-specified exclusions, analysis was based on 12,426 subjects (92 to 1018 per occupational group). As expected, there was high usage of computer keyboards by office workers, while nurses had the highest prevalence of heavy manual lifting in all but one country. There was substantial heterogeneity between occupational groups in economic and psychosocial aspects of work; three- to five-fold variation in awareness of someone outside work with musculoskeletal pain; and more than ten-fold variation in the prevalence of adverse health beliefs about back and arm pain, and in awareness of terms such as "repetitive strain injury" (RSI). CONCLUSIONS/SIGNIFICANCE: The large differences in psychosocial risk factors (including knowledge and beliefs about MSDs) between occupational groups should allow the study hypothesis to be addressed effectively.

Analysis of the lifted weight including height and frequency factors for workers in Colombia.

Factors related to the height of the load and the frequency of handling have become a way to predict the acceptable standard weight lifted for workers whose main task is the manual lifting of materials and measuring the conditions is important to determine a maximum weight lifted. This study was conducted to twenty (20) workers between eighteen (18) and forty (40) years old with a minimum six months experience and belonging to the warehouse and packaging area of a dairy products company. Consideration was given to three different heights such as knuckle, shoulder and total height as well as frequencies of 2, 4 and 6 times per minute. Average values for lifted weight were 17.9306 ± 2.37 kg. The conclusions and recommendations included a review of legislation related to Colombian maximum acceptable weight of lifting due to the current law does not match the acceptable weight handled in this research.

Prevención de trastornos musculoesqueléticos de las extremidades superiores relacionados con el trabajo: revisión sistemática / Prevention of upp er-extremity musculoskeletal work-related disor ders: a systematic review

Objetivos: Revisar la evidencia disponible sobre la efectividad de las intervenciones que buscan reducir la ocurrenciade trastornos musculoesqueléticos de extremidad superior o sus factores de riesgo en el ámbito laboral.Métodos: Se realizó una búsqueda en OVID, Cochrane y EBSCO Host de artículos publicados en revistas científicasentre 1990 y 2008. Se excluyeron aquellos estudios donde las intervenciones no se llevaron a cabo en ambientes laborales.Dos pares académicos seleccionaron y revisaron los artículos. Los resultados se generaron a partir de la cantidad y calidadde artículos con conclusiones similares en relación a diversos tipos de intervención.Resultados: Cincuenta y un estudios fueron seleccionados en esta revisión. Todos ellos describen distintas intervencionespreventivas en los lugares de trabajo y sobre los trabajadores, principalmente entre usuarios de pantallas de visualizaciónde datos (PVDs). Solo doce estudios fueron considerados de alta calidad. Se encontró evidencia moderada del beneficio decambios integrales en el puesto de trabajo, de actividades formativas sobre los trabajadores y del uso de algunos teclados yratones alternativos que permiten adoptar posturas más apropiadas de la extremidad superior.Conclusiones: La heterogeneidad y frecuente debilidad metodológica de los estudios encontrados impide que se puedaconcluir sobre la efectividad de la mayoría de las intervenciones descritas en la literatura. Se hacen especialmente necesariasevaluaciones de intervenciones sobre puestos de trabajo con riesgos diferentes de los derivados del uso de PVDs (AU)

Objectives: To study the effectiveness of workplace interventions aimed at reducing the occurrence of upper-extremitymusculoskeletal disorders or their related risk factors.Methods: Articles published between 1990 and 2008 were searched in OVID, Cochrane, y EBSCO Host databases.Interventions not conducted at the workplace were excluded. Two peers selected and reviewed the articles. The results are based on the quantity and quality of articles providing similar conclusions regarding different types of interventions. Results: Fifty-one studies were included in this review, all describing a variety of preventive interventions in workplacesand on workers, mainly among visual display unit (VDUs) users. Only twelve studies in the review were considered of highquality. We found moderate evidence for the benefits of comprehensive changes in workplaces, educational interventionsin workers and use of alternative computer input devices intended to achieve more adequate upper-extremity postures.Conclusions: The heterogeneity and frequent methodological flaws of reviewed studies do not allow us to reach conclusiveresults on the effectiveness of the most reviewed interventions. Evaluation studies of interventions for risks other thancomputer-related ones are greatly needed (AU)