© 1992 Faculty of Public Health Medicine of the Royal Colleges of Physicians of the United Kingdom
research-article |
Unexpected high mortality rates found in a review of district statistics: what action is appropriate?
Nigel Bruce, Locum Consultant in Public Health Medicine
Department of Public Health and Primary Care, Royal Free Hospital Medical School Rowland Hill Street, London NW3 2PF
Hampstead Health Authority 21 Pont Street, London NW3 2PN
The regular review of statistical and other data is now a routine public health activity in district health authorities. The interpretation of findings indicative of high or otherwise unexpected rates of mortality or disease may be complicated by small numbers, and also by questions concerning the reliability with which the available data describe the problems. Judgement about whether to undertake further investigation of these problems is subject to uncertainty about the likely effectiveness and efficiency of the investigation, and of any remedial action that would be expected to follow. Examples of these problems are explored in relation to the finding of a high rate of infant and late neonatal mortality in a district population, and a high rate of female suicide.
The late neonatal death rate showed a rising trend over a period of four years and was significantly elevated above national and regional rates. The perinatal death rate was not correspondingly low, nor had there been an excess of multiple births over the period. A review of neonatal death certificates did not demonstrate any identifiable problems relating to either the cause or place of death, and the high rate subsequently reverted to the expected level without further intervention. In the case of female suicide, analyses including deaths by misadventure and open verdicts were carried out to allow for possible differences between men and women in the certification of suicide. However, this did not alter the conclusions, and further investigation of the circumstances of death is planned to assess the potential for preventive action in the locality.
Practical experience of monitoring epidemiological data in districts and any subsequent investigations needs to be shared and evaluated. This will assist public health doctors and others working in this field to make appropriate judgements about the interpretation of health statistics and other data at the district level, and about the level of investigation required.