Cost outcomes
Tables 2 and 3 show the primary outcomes of the study from the service-provider perspective. The mean total cost per patient of the Tertiary Unit was moderately higher than that of the Secondary Unit but the difference was not statistically significant (\euro577.5 ± \euro219.6 vs. \euro394.7 ± The mean cost per visit of both units was quite similar (\euro182.8 ± \euro41.47 in the Tertiary vs. \euro184.6 ± Unit; P =0. 0.9056). An analysis of general costs revealed that direct and structural costs per patient of the two units were not significantly different. Conversely, indirect costs of the Tertiary Unit were significantly higher than those of the secondary center unit (\euro49.93 ± \euro19.90 vs. \euro12.42 ± \euro2.344, respectively; P =0.0018) (Table 2).
An individual assessment of the five single components of direct costs showed that personnel costs were significantly higher in the Tertiary (\euro68.75 ± \euro14.90) than in the Secondary Unit (\euro36.90 ± costs were slightly but nonsignificantly higher in the former (\euro197.6 ± \euro111.6 vs. direct cost components, namely imaging and endoscopy, biopsy and cytology techniques, and specialist consultation and referral were not significantly different (Table 3).
We further calculated the percentage contribution of each cost component to the mean cost per patient. In both units, direct costs accounted for the largest proportion of cost per patient without significant differences (79.13 percent [95% confidence interval, 77.12-81.14] in the Tertiary vs. 81.15 percent [77.53-84.76] in the Secondary Unit; P =0.3327). However, the percentage contribution of indirect costs to the mean cost per patient was significantly higher in the unit of the tertiary center (8.595 [8.377-8.813] vs. 3.284 percent [2.618-3.950], respectively; P <0.0001) (Table 2).
When looking at the rate of sharing of each fraction of direct costs in the mean cost per patient, laboratory and pathology and imaging and endoscopy costs accounted for the largest amount, with a significantly higher percentage contribution of imaging and endoscopy costs in the secondary vs. tertiary center unit. Whereas costs of biopsy and cytology techniques and specialist consultation and referral accounted for a tiny fraction of the cost per patient in both units without relevant differences, the average contribution of personnel costs was significantly higher in the Tertiary compared to the Secondary Unit (12.58 percent [10.64-14.51] vs. 9.746 percent [8.029-11.46], respectively;P =0.0373) (Table 3).
We also examined the relevant costs of patients from both units according to clinical data (Tables 4 and 5). Patients referred for symptoms suggestive of cancer and those with a final diagnosis of cancer were more often referred from the emergency department to the unit of the tertiary center and from primary care centers to the Secondary Unit (P <0.0001 in both cases). For patients referred for symptoms suggestive of cancer, no significant differences were observed in the mean cost per patient between the Tertiary and the Secondary Unit (\euro782.52 ±P =0.0537) (Table 4). Likewise, there were no significant differences in the cost per patient between the Tertiary and the Secondary Unit with regard to a final diagnosis of malignancy (\euro1,069.17 ± \euro218.64 vs. \euro827.65 ± \euro151.83, respectively; P =0.0871) (Table 5). Consistent with the results of the main analysis, cost differences continued to lie in personnel and indirect costs both for patients referred for symptoms suggestive of cancer (Table 4) and for patients with a final diagnosis of cancer (Table 5).