Post discharge surveillance methods: a critique

Abstract

Mortality, morbidity and costs related to surgical site infections (SSI) are significant. It is therefore important to perform surveillance for SSI to determine the quality of care and identify areas for improvement. An increasing number of SSI manifest after discharge due to shorter hospital stays and, as a result, traditional methods of infection surveillance fail to detect these infections. Post discharge surveillance is thus required in order to obtain an accurate infection rate. Despite this, post discharge surveillance is not routinely conducted and there is no recommended, standardised approach. This paper presents a critique of 12 studies using different post discharge surveillance methods such as patient and surgeon questionnaires, telephone interview, outpatient clinic follow-up or a combination of approaches. While all methods were effective, issues concerning poor response rates, lack of standard definitions and potential reporting bias affected the reliability and validity of results. Procedural approaches such as the timing and method of questionnaire distribution to patients and surgeons and the data collection technique influenced response rates. The use of a valid and reliable patient questionnaire distributed within 30 days of surgery, using standard criteria for SSI based on the definitions provided by the Centers for Disease Control and Prevention (CDC) is recommended. Post discharge surveillance should also include telephone follow-up with responders who indicate infection, non-responders and the physician diagnosing infection. This method is relatively inexpensive and achieves a high response rate and an accurate diagnosis. Results are more likely to be valid if corroborating evidence is obtained and when the assessment is conducted by independent experts to reduce bias.