LETHALITY (Latin letalis deadly; synonym deadliness) — the relation of number of the dead from any disease to number having this disease; it is usually expressed as a percentage. L. it is not necessary to mix with mortality (the relation of number of the dead from this disease to average population, among to-rogo diseases were observed). Distinguish hospital L. (the relation of number of the left patients who died in hospital of any disease to number — written out and died), extra hospital L. (the relation of number of the dead to number who were ill, treated on an outpatient basis), postoperative L. (the relation of number of the operated patients who died after operation to number). L. serves one of indicators of quality and overall performance to lay down. - professional, institutions it is also usually estimated on the basis of official to become. reports or by special processing of primary medical documentation (case histories, cards left a hospital). Indicators of L. are used also in kliniko-statistical and pilot scientific research for assessment of result of observations and as criterion of efficiency to lay down. actions.
Size of an indicator of L. in separate to lay down. - professional, institutions depends not only on the level of statement in them diagnostic and to lay down. works, but also from the list of patients, their age, the nature of pathology, weight of a state, timeliness of the request for medical aid (for hospital, and, especially, postoperative L. — delivery periods in a hospital), qualities of the previous treatment, etc. factors. Therefore to use of indicators of L. at assessment of activity to lay down. - professional, institutions it is necessary to approach with the known care, surely considering specifics of the contingent of the patients who were on treatment. So, at assessment of indicators of hospital JT. on hospital in general it is necessary to consider existence of specialized departments, the list of patients, an order of selection for hospitalization. Besides, hospital L. as criterion of activity-tsy it is reasonable to consider in comparison with the general L. and mortality. Also simultaneous dynamics hospital and extra hospital L is important., their ratio, given about the number of the dead at home from earlier hospitalized patients. Indicators of L deserve attention. in the first days of stay of patients in a hospital (less than 24 hours L.), characterizing quality of both the hospital, and extra hospital help. Comparison of indicators of L is the most reliable. on the departments of the same BCs of the same name or on the diseases of the same name. In need of comparison of the general indicators of a lethality on hospitals and departments it is necessary to carry out standardization of indicators. In cases of small number of the compared groups of patients it is necessary to define reliability of distinctions of indicators (see. Sanitary statistics ).
Dynamics of indicators of L. in many respects depends on change of social and economic conditions, development of network to lay down. - professional, institutions, improvement of diagnostic methods and efficiency of treatment. So, L. in pre-revolutionary Russia it would be extremely high. As a result of improvement a dignity. conditions of the country, living conditions and working conditions, first progress of owls. health care in the field of fight with inf. diseases hospital L. from a number of diseases in 1922 — 1926 considerably decreased (tab. 1).
Systematic carrying out effective measures for health protection of children caused falloff hospital L. in children's hospitals (tab. 2)
Considerable decrease hospital L. it was observed during the post-war period as a result of improvement of living conditions and essential upgrading of medical aid.
In 1959 hospital L. after the emergency surgical interventions on average on hospitals of RSFSR, according to G. N. Beletsky, made (in %): at an acute appendicitis 0,16; at the restrained hernia 2,5; at a perforated ulcer 3,55; at impassability of intestines 15,5; at an extrauterine pregnancy 0,25.
As a result of universal improvement of medical aid and its specialization, unification of methodical and organizational approach to treatment of patients, a wide spread occurance of the best practices and implementation of scientific achievements in practice to lay down. institutions indicators of L. in hospitals of the country were established at the level reflected in table 3.
See also Mortality .
Table 1. The ANNUAL AVERAGE LETHALITY IN HOSPITALS of ST. PETERSBURG (1886 — 1909). And LENINGRAD (1922 — 192 6) according to V. I. Binshtok, 19 28 g)
Table 2. ANNUAL AVERAGE POVOZRASTNAYa the LETHALITY of CHILDREN FROM PNEUMONIA IN the MOSCOW CHILDREN'S HOSPITAL to them. I. V. RUSAKOVA in 1925 — 1928 and in 1953 — 1956 (according to V. A. Kruzhkov, 1957)
Table 3. The HOSPITAL LETHALITY AT SOME DISEASES AT ADULTS And &DETEYNBSP; &vnbsp; 1975 — 1978.
Bibliography: Averbukh L. A. Level of an over-all mortality at separate diseases, the Doctor, business, No. 4, page 405, 1960; Bath-to and with G. A. Questions of sanitary and demographic statistics, page 57, M., 1964; Merkov A. M. and Polyakov L. E. Sanitary statistics, page 40, L., 1974; New rural S. A. Demografiya and statistics, page 16, M., 1978; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 1, page 418, M., 1951; Petrovsky B. V. Achievements of the Soviet health care for years of the ninth five-years period, page 88, M., 1976; I. S. and Church G. F is accidental. Statistical information in management of healthcare institutions, page 158, M., 1976.
A. M. Merkov, I. S. Sluchayno.