The inter-rater reliability of the diagnosis of surgical site infection in the context of a clinical trial

J Nuttall; N Evaniew; P Thornley; A Griffin; B Deheshi; T O'Shea; J Wunder; P Ferguson; R L Randall; R Turcotte; P Schneider; P McKay; M Bhandari; M Ghert

doi:10.1302/2046-3758.58.BJR-2016-0036.R1

The inter-rater reliability of the diagnosis of surgical site infection in the context of a clinical trial

Bone Joint Res. 2016 Aug;5(8):347-52. doi: 10.1302/2046-3758.58.BJR-2016-0036.R1.

Authors

J Nuttall¹, N Evaniew¹, P Thornley¹, A Griffin², B Deheshi³, T O'Shea⁴, J Wunder⁵, P Ferguson⁶, R L Randall⁷, R Turcotte⁸, P Schneider⁹, P McKay⁹, M Bhandari¹⁰, M Ghert¹¹

Affiliations

¹ Orthopaedic Resident, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada.
² University Musculoskeletal Oncology Unit | Mount Sinai Hospital, Toronto, Ontario, Canada.
³ Department of Surgery, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada.
⁴ Department of Medicine, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada.
⁵ University of Toronto, Toronto, Ontario, Canada.
⁶ Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Suite 476(G) | Toronto, M5G 1X5, Canada.
⁷ Department of Orthopaedics, University of Utah, 2000 Circle of Hope, Suite 4260 | Salt Lake City, 84112-5550, USA.
⁸ Division of Orthopaedic Surgery, McGill University, Montreal General Hospital, 1650 Cedar Avenue, Room B5.159.6, Montreal, QC, H3G 1A4, Canada.
⁹ Department of Clinical Epidemiology and Biostatistics, McMaster University, 293 Wellington Street North, Suite 110, Hamilton, ON, L8L 8E7, Canada.
¹⁰ Department of Clinical Epidemiology and Biostatistics and Department of Surgery, McMaster University, 293 Wellington Street North, Suite 110 | Hamilton, ON, L8L 8E7, Canada.
¹¹ Department of Surgery, McMaster University, 711 Concession Street, Surgical Offices B3 169A, Hamilton, ON, L8V 1C3, Canada [email protected].

PMID: 27528711
PMCID: PMC5013894
DOI: 10.1302/2046-3758.58.BJR-2016-0036.R1

Abstract

Objectives: The diagnosis of surgical site infection following endoprosthetic reconstruction for bone tumours is frequently a subjective diagnosis. Large clinical trials use blinded Central Adjudication Committees (CACs) to minimise the variability and bias associated with assessing a clinical outcome. The aim of this study was to determine the level of inter-rater and intra-rater agreement in the diagnosis of surgical site infection in the context of a clinical trial.

Materials and methods: The Prophylactic Antibiotic Regimens in Tumour Surgery (PARITY) trial CAC adjudicated 29 non-PARITY cases of lower extremity endoprosthetic reconstruction. The CAC members classified each case according to the Centers for Disease Control (CDC) criteria for surgical site infection (superficial, deep, or organ space). Combinatorial analysis was used to calculate the smallest CAC panel size required to maximise agreement. A final meeting was held to establish a consensus.

Results: Full or near consensus was reached in 20 of the 29 cases. The Fleiss kappa value was calculated as 0.44 (95% confidence interval (CI) 0.35 to 0.53), or moderate agreement. The greatest statistical agreement was observed in the outcome of no infection, 0.61 (95% CI 0.49 to 0.72, substantial agreement). Panelists reached a full consensus in 12 of 29 cases and near consensus in five of 29 cases when CDC criteria were used (superficial, deep or organ space). A stable maximum Fleiss kappa of 0.46 (95% CI 0.50 to 0.35) at CAC sizes greater than three members was obtained.

Conclusions: There is substantial agreement among the members of the PARITY CAC regarding the presence or absence of surgical site infection. Agreement on the level of infection, however, is more challenging. Additional clinical information routinely collected by the prospective PARITY trial may improve the discriminatory capacity of the CAC in the parent study for the diagnosis of infection.Cite this article: J. Nuttall, N. Evaniew, P. Thornley, A. Griffin, B. Deheshi, T. O'Shea, J. Wunder, P. Ferguson, R. L. Randall, R. Turcotte, P. Schneider, P. McKay, M. Bhandari, M. Ghert. The inter-rater reliability of the diagnosis of surgical site infection in the context of a clinical trial. Bone Joint Res 2016;5:347-352. DOI: 10.1302/2046-3758.58.BJR-2016-0036.R1.

Keywords: Endoprosthetic reconstruction; Infection; Reliability.