Sickness absence in male Royal Naval medical and dental branch ratings: 1981-1989.

Sickness episodes for the male members of the medical and dental branch of the Royal Navy were compared with those for a control group consisting of other male naval ratings over the period 1981-1989. Age-corrected statistical analysis showed the study group to have had a significantly higher (P < 0.001) number of sickness episodes. An estimate of under-reporting was carried out by taking a sample of weekly sick lists and establishing which cases should have been reported and which actually had been reported. In the sample from a naval hospital, 67.8% (120/177) of cases that should have been reported were actually reported. This figure dropped to 46.8% (171/365) for a naval shore establishment. From this information, correction factors were derived and applied to the sickness episode data. The resulting difference in episodes was not statistically significant between groups. When the study group was compared with male NHS workers, both the observed rates and the estimated rates for the study group were much lower than those for the NHS groups. Bias due to under-reporting was probably a major factor in the overall difference originally observed.