Determinants of orthopedic physicians’ self-reported compliance with surgical site infection prevention: results of the WACH-trial’s pilot survey on COM-B factors in a German university hospital
Authors: Tomsic Ivonne , Ebadi Ella , Gossé Frank , Hartlep Ina , Schipper Pamela , Krauth Christian , Schock Bettina , Chaberny Iris F. , von Lengerke Thomas 
Published: April 2021

Abstract
Background
Prevention of surgical site infections (SSIs), which due to their long-term consequences are especially critical in orthopedic surgery, entails compliance with over 20 individual measures. However, little is known about the psychosocial determinants of such compliance among orthopedic physicians, which impedes efforts to tailor implementation interventions to improve compliance. Thus, for this professional group, this pilot survey examined psychosocial determinants of self-reported compliance, which have been theoretically derived from the COM-B (Capability, Opportunity, Motivation and Behavior) model.

Methods
In 2019, a cross-sectional survey was conducted in a tertiary care university orthopedic clinic in Hannover, Germany, as a pilot for the WACH-trial (“Wundinfektionen und Antibiotikaverbrauch in der Chirurgie” [Wound Infections and Antibiotics Consumption in Surgery]). Fifty-two physicians participated (38 surgeons, 14 anesthesiologists; response rate: 73.2%). The questionnaire assessed self-reported compliance with 26 SSI preventive measures, and its psychosocial determinants (COM-B). Statistical analyses included descriptive, correlational, and linear multiple regression modeling.

Results
Self-reported compliance rates for individual measures varied from 53.8 to 100%, with overall compliance (defined for every participant as the mean of his or her self-reported rates for each individual measure) averaging at 88.9% (surgeons: 90%, anesthesiologists: 85.9%; p = 0.097). Of the components identified in factor analyses of the COM-B items, planning, i.e., self-formulated conditional plans to comply, was the least pronounced (mean = 4.3 on the 7-point Likert scale), while motivation was reported to be the strongest (mean = 6.3). Bi-variately, the overall compliance index co-varied with all four COM-B-components, i.e., capabilities (r = 0.512, p < 0.001), opportunities (r = 0.421, p = 0.002), planning (r = 0.378, p = 0.007), and motivation (r = 0.272, p = 0.051). After mutual adjustment and adjustment for type of physician and the number of measures respondents felt responsible for, the final backward regression model included capabilities (β = 0.35, p = 0.015) and planning (β = 0.29, p = 0.041) as COM-B-correlates.

Conclusion
Though based on a small sample of orthopedic physicians in a single hospital (albeit in conjunction with a high survey response rate), this study found initial evidence for positive correlations between capabilities and planning skills with self-reported SSI preventive compliance in German orthopedic physicians. Analyses of the WACH-trial will further address the role of these factors in promoting SSI preventive compliance in orthopedic surgery.
Trial registration: This survey was conducted as part of the research project WACH ("Wundinfektionen und Antibiotikaverbrauch in der Chirurgie" [Wound Infections and Antibiotic Consumption in Surgery]), which has been registered in the German Clinical Trial Registry (https://www.drks.de/; ID: DRKS00015502).