Occupational injuries can induce functional limitations in workers both at home and in work settings. In this study, two instruments, the Stanford Health Assessment Questionnaire (HAQ) and the Short-Form 36 (SF-36) were used to document both the immediate and shortterm effects of injuries in municipal workers who suffered mainly from strains and sprains. Telephone interviews were conducted with injured workers approximately one week, two weeks, one month, and three months following their injuries. One hundred and fourteen subjects agreed to participate in the study; 90 workers completed at least one useable interview; 78 completed all four interviews. Cox hazards proportional models were used to predict lost time from work, and to test the sensitivity of the instruments to within-subject change and return to work. The mean HAQ scores indicated moderate disability during the first week of recovery. At one-month following the injuries, workers still demonstrated moderate functional limitations in ability to complete errands and household chores. Moderate disability, as indicated by self report of pain, decreased sense of well being, fatigue, and sleep problems, also persisted up to one-month. Except for measurement of general health and mental health, the mean SF-36 scores on the six remaining subscales were well below the population mean scores up to one-month following the injuries. Scores for physical functioning, role-physical, and bodily pain continued to differ significantly from population mean scores three-months following the onset of injury. HAQ scores and subscales of the SF-36, physical functioning, role physical, and bodily pain were highly correlated at each time period (r = >.59 for all, p = <.001). Hazard ratios for lost days were calculated for the physical health component summary score of the SF-36, as well as the following subscales: bodily pain, physical functioning, and role physical. Each measure demonstrated a significantly elevated risk of lost time for scores indicating poorer functioning. For example, using the physical component summary scale of the SF-36, subjects whose scores were one standard deviation lower were more than twice as likely to experience an extended lost time episode than those with higher scores (hazard ratio = 2.36, 95% C.I. = 1.73 - 3.22, p = <.001). Limitations in physical functioning, physical role, and bodily pain persisted in workers after relatively minor workplace injuries despite a 91% return to work rate. Both the HAQ and the physical functioning subscale of the SF-36 are sensitive to change in function related to acute occupational injuries and both are moderately correlated with work days lost.
University of California at San Francisco, School of Nursing, Department of Community Health Systems, Box 0608, San Francisco, CA 94143-0608
University of California at San Francisco, School of Nursing, Department of Community Health Systems, San Francisco, California