NCD and risk calculator

The Japanese NCD adopted a “web-based collection” in 2011 with significant support from Japan Surgical Society [4]. The NCD is a nationwide collaboration associated with the Japanese Surgical Board Certification System, in which data on 1.6 million surgical procedures from > 4000 hospitals were collected in 2014. It is linked to the second level in the specialty chest surgery hierarchy through a web-based conversion, both of which are supported by the Japanese Board of General Thoracic Surgery [5].

The RC indicates the predictive incidence ratio of surgery-related death and major complications, based on a model of lung cancer surgery risk derived from the Japanese nationwide web-based database of 78,594 patients during 2014–2015 [6]. In this study, the primary outcome measures were surgical mortality, and the combined outcome of mortality and major morbidity. Operative mortality included patients who died within 30 days after surgery, and major morbidity was defined in accordance with the Society of Thoracic Surgeons (STS) risk models [7, 8]. Endo et al. [6] reported that the most common cause of major morbidity was respiratory failure after pneumonia and atrial arrhythmia. Multivariate risk models were developed in the report [6], and the final logistic model with odds ratios (ORs) and 95% confidence intervals (CIs) is presented in Supplementary Table 1, which shows associations between mortality or mortality/major morbidity, and patient baseline characteristics. Nineteen variables were associated with mortality, and 25 variables were associated with mortality/major morbidity. The RC’s mean predictive probability of perioperative mortality or major morbidity (PPMM) can be calculated based on OR of each variable in above risk model list (Supplementary Table 1). If we access Internet website (https://registry3.ncd.or.jp/karte/page/feedback/riskcalc?specialist_id=A00056_001) online, and enter 20 variables associated with mortality/major morbidity (sex, age, performance status, pulmonary function tests, preoperative comorbidity, smoking history, induction therapy, radiological tumor size, clinical stage, surgical procedure, histology, etc.), it will produce a predictive incidence ratio of surgery-related death and severe complications.