Data on sickness absence in some recent publications of the Ministry of Pensions and National Insurance.

William Farr and many other pioneers advocated the systematic collection of data on incapacity from non-fatal disease. The National Insurance Act of 1946 provided for the compulsory insurance of everybody between school-leaving and retirementpensionable age with the exception of married women, and also for payment of sickness benefit; this for the first time made possible the collection of national data on "sickness absence". Since 1950 the Annual Reports of the Ministry of Pensions and National Insurance (now the Ministry of Social Security) have given some information about sickness absence in this country (England, Wales, and Scotland); the most recent report (1965) gives figures for incapacity for work in 1963-4. Tabulations are provided for spells of incapacity; for spells commencing, spells current, and total days in the period; for males and females; by cause. This information has been amplified periodically by the "Digest of Statistics" (1958-61), which is available on request to research workers and others interested in public health (from the Statistics Division of the Ministry). The "Digests" relate to a 5 per cent. sample of the insured population. The first dealt with the calendar year 1951; the latest, published in 1965, is for June, 1958, to May, 1961. The "Digests" contain data again on spells of incapacity derived from the claims for benefit; spells commencing in the period (by cause and age); spells of incapacity terminating in the period (by cause and duration); and number of claimants incapacitated on the last day of the period (by cause and age, and by duration and age). Based on the 1951 population-at-risk, age-standardized rates for 1953-4 onwards are provided for spells and for their duration. The "International Statistical Classification of Disease" List C, containing fifty groups of Causes for Tabulation of Morbidity for Social Security Purposes is used, but components of groups are listed where numbers permit, so that figures are given, in all, for about 140 groups. The length of spells is not normally distributed (there is a tail of very long spells); the final certificate moreover is used for diagnosis of sickness, which has a disruptive effect due to change of diagnosis. The median, therefore, is provided as a better indication of change over the years than the mean. The introduction and notes comment on the trends in sickness incapacity, indicating the conditions in which changes are unlikely to be due to chance, but the "Digests" are a source of raw data rather than of interpretation and informed discussion. The "Digests" provide a mass of data on current causes of sickness-absence, and on the trends over the years; they are thus of use in identifying conditions causing significant morbidity in the working community. The special "Report on the Inquiry into the Incidence of Incapacity for Work" is now published in two parts: