RESUMEN
Use of computers with disregard ergonomics may lead to health problems, long-term discomfort and physical disabilities and lose workdays. To assess the effectiveness of an ergonomic education to modify of body posture, ergonomic risk factors and musculoskeletal pain severity in computer users. In this Quasi-experimental randomized controlled study, computer users were assigned to two groups: case group [n=75] receiving the theory based on intervention by using construct of theory of planned behavior and stage of change, and control group [n =75]. Both groups were evaluated at the beginning of the study and 3 and 6 months later. The following tools were used: the Rapid upper limp Assessment [RULA] method to assess upper-extremity work-related posture, self administrated questionnaire that evaluated TPB constructs, stage of change algorithm, ergonomic risk factors checklist, ergo- knowledge quiz and VAS for assessing musculoskeletal pain severity. The intervention included two program elements: staged matched informative brochure and personalized preventive educational counseling. The intervention group had significantly higher scores than controls in ergo-knowledge, attitudes, perceived behavior control, intention, as well as non natural posture maintenance as goal behavior [P<0.05] Also, finding showed the significant diminish in musculoskeletal pain severity [P<0.05]. At 3 and 6 months follow up, no significant differences were found between the two groups for subjective norms constructs. Intervention couldn't improve RULA risk level to low and very low area [1, 2 level] and only decreased risk exposure to medium level. According to the results preventive ergonomic campaigns would be more successful if educational intervention regarded as a part of multifaceted interventions: analysis and elimination of risk factors, engineering controls and administrative controls