[Length of work disability and associated factors]

To estimate the mean length of temporary work disability (TD) and to assess some of its possible determinants.

During 1995, we registered 12,570 cases of TD among people from the Inspection Area of Alcala of Henares. We obtained a random sample of 600 cases. In addition to TD length, we obtained information about patients' sociodemographic characteristics, social security group, diagnosis, and type of primary care. Analysis of variance was used to compare means and Cox regression models were used to estimate risk ratios for factors influencing return to work.

The mean and the median of the TD were 44.5 and 11 days respectively. The TD length was less than one month in 72.9% of the cases. The TD length was similar in both sexes and showed a positive association with age (p=0.0002). The General group had higher TD length than the Insalud group and lower than the Autonomous and Housework groups. The Insalud personnel showed an adjusted relative effect (and 95% confidence intervals) in the probability of returning to work of 2 (1.07-3.73) compared to the General group. The adjusted relative risk was 0.89 (0.88-0.90) for an increase of 5 years of age.

The most important factors in the TD length were age and social security group. The improvement in the health system accessibility is one of the factors that may positively affect the probability of returning to work.