Costs, Risks and Benefits of Surgery: a milestone in the development of health services research

Finding discriminative and interpretable patterns in sequences of surgical activities

OBJECTIVE

Surgery is one of the riskiest and most important medical acts that is performed today. Understanding the ways in which surgeries are similar or different from each other is of major interest to understand and analyze surgical behaviors. This article addresses the issue of identifying discriminative patterns of surgical practice from recordings of surgeries. These recordings are sequences of low-level surgical activities representing the actions performed by surgeons during surgeries.

MATERIALS AND METHOD

To discover patterns that are specific to a group of surgeries, we use the vector space model (VSM) which is originally an algebraic model for representing text documents. We split long sequences of surgical activities into subsequences of consecutive activities. We then compute the relative frequencies of these subsequences using the tf*idf framework and we use the Cosine similarity to classify the sequences. This process makes it possible to discover which patterns discriminate one set of surgeries recordings from another set.

RESULTS

Experiments were performed on 40 neurosurgeries of anterior cervical discectomy (ACD). The results demonstrate that our method accurately identifies patterns that can discriminate between (1) locations where the surgery took place, (2) levels of expertise of surgeons (i.e., expert vs. intermediate) and even (3) individual surgeons who performed the intervention. We also show how the tf*idf weight vector can be used to both visualize the most interesting patterns and to highlight the parts of a given surgery that are the most interesting.

CONCLUSIONS

Identifying patterns that discriminate groups of surgeon is a very important step in improving the understanding of surgical processes. The proposed method finds discriminative and interpretable patterns in sequences of surgical activities. Our approach provides intuitive results, as it identifies automatically the set of patterns explaining the differences between the groups.

The emergence of clinical practice guidelines

Clinical practice guidelines are now ubiquitous. This article describes the emergence of such guidelines in a way that differs from the two dominant explanations, one focusing on administrative cost-cutting and the other on the need to protect collective professional autonomy. Instead, this article argues that the spread of guidelines represents a new regulation of medical care resulting from a confluence of circumstances that mobilized many different groups. Although the regulation of quality has traditionally been based on the standardization of professional credentials, since the 1960s it has intensified and been supplemented by efforts to standardize the use of medical procedures. This shift is related to the spread of standardization within medicine and especially in research, public health, and large bureaucratic health care organizations.