Sepsis in surgical wounds Multiple regression analysis applied to records of post-operative hospital sepsis

Abstract

The method of multi-regression analysis as applied to data which are classified in a non-metric manner is discussed, and a set of data relating the risk of post-operation sepsis to various factors is analysed in this way.Age over 60, male sex, long duration of operation, incision over 6 in. long and the insertion of a drain in the wound are all found to be associated with increased risk of post-operative sepsis. Operations for appendicectomy and those on the gall bladder have a relatively high basic risk of developing sepsis while operations for gastrectomy or those on the thyroid, and probably thoracic operations, have a low basic risk. The substantial differences in the gross risk of post-operative sepsis associated with the operations performed in the different hospitals included in the analysis are shown to be almost entirely accounted for by differences in the operations performed in them.