[Impact assessment of the implementation of an integrated care model for thyroid disease at the University Hospital "Federico II" of Naples (Campania Region, Southern Italy): an interrupted time series analysis].

Objectives: to evaluate the implementation of an integrated care model for thyroid disease on thyroid surgery at the University Hospital "Federico II" of Naples (Campania Region, Southern Italy).

Design: quasi-experimental design employing an interrupted time series analysis.

Setting And Participants: all subjects who were admitted to the University Hospital "Federico II" for thyroid surgery between January 2008 and December 2018. The integrated care model for thyroid disease was implemented starting from January 2016.

Main Outcome Measures: rate of partial thyroidectomies over all thyroidectomies; rate of diagnosed thyroid cancers over all diagnosed thyroid tumours; length of stay (LOS). Differences pre- and post-interventions were assessed employing Poisson (for count outcomes) and linear (for continuous outcomes) regression models. Models were adjusted for age, gender, tumour diagnosis (none, benign, malignant), Charlson index, and discharge month.

Results: data on 4,233 thyroidectomies were included. There was no difference between pre- and post-intervention trends for the rate of partial thyroidectomies over all thyroidectomies (pre-intervention: IRR 1.00; 95%CI 0.99;1.00 - post-intervention: IRR 1.00; 95%CI 0.98;1.02) and for the rate of diagnosed thyroid cancers over all thyroid tumours (pre-intervention IRR 0.99; 95%CI 0.99;1.00 - post-intervention IRR 1.00; 95%CI 0.99;1.01). On the contrary, the LOS reduced from 4.5 (±4.3) days in 2008 to 3.2 (±3.2) days in 2018. The multivariate analysis confirmed this reduction, estimated to be 1.1 days on average in the pre-intervention eight-year period (pre-intervention coefficient -0.01; 95%CI -0.02;-0.01), followed by an even greater reduction in the post-intervention three-year period which was estimated to be 1.1 day (post-intervention: coefficient -0.03; 95%CI -0.05;-0.01).

Conclusions: the implementation of an integrated care model for thyroid disease contributed to reduce the LOS for thyroidectomies, improving the efficiency in the management of thyroid disease. However, this intervention had no impact in reducing the rate of total thyroidectomies.