<p>Table 4. Effect of Primary Care Physicians’ characteristics on 3-year mean costs (in Euros) of primary and specialist healthcare Primary care Specialist care difference in costs difference in costs</p><p>(SE) (SE) a a a Male sex of PCP¶, n(%) 15 (38) -10 (20) -100 (66) Involvement in education of medical students and/or vocational PCP training, 32 (82) -5 (36) 59 (91) n(%)</p><p>General characteristics b Practice sizec 2.4 (1.1) -23 (9) -35 (32) Experience (years)d 17 (9) -1 (1.1) -0.2 (4) Mean number of active problems per patient on problem list 1.7 (0.5) -73 (17) -289 (51) Mean number of contacts (adjusted for age and sex of the patient) 2.8 (0.3) 13 (39) -80 (131) Mean percentage of all problems that was psychological or social 12 (3) -1 (93) 2 (11)</p><p>Special interest in managinge Diabetes mellitus 3.2 (0.7) 0 (16) 24 (52) COPD f /Asthma 3.1 (0.7) -23 (14) -50 (45) Cardiovascular disease 3.0 (0.5) -20 (18) -146 (58)</p><p>Anxiety 2.9 (0.8) -11 (13) -80 (41) Depression 3.0 (0.7) -15 (14) -68 (46) Medically Unexplained Symptoms 4.0 (0.7) 10 (14) 33 (47) ______¶ PCP indicates primary care physician a Numbers in brackets are standard errors, unless indicated otherwise b In Euros per unit of the scale of the characteristic c Divided in 4 classes: class 1:0-1000 patients; class 2:1001-1250 patients; class 3:1251-1500 patients; class 4:>1500 patients. Range 312-2,714 patients. d Per (additional) year experience e Five levels of interest (from 1 (no special interest) to 5 (very much interest)) and 5 levels of percentage of patients treated by the GP (0%-100%). See additional file 2 f Chronic Obstructive Pulmonary Disease</p>