eTable 5. Appendectomy case numbers, mortality, and morbidity, stratified by severity of appendicitis (uncomplicated or complicated).

			2010		2011		2012		2013		2014		2015		2016		2017
			n	%	n	%	n	%	n	%	n	%	n	%	n	%	n	%
Total number of patients			113 614	100.0	113 975	100.0	111 957	100.0	108 437	100.0	107 322	100.0	104 922	100.0	102 997	100.0	102 464	100.0
Hospital size	≤ 20 000 cases per year	Uncomplicated appendicitis	62 791	83.0	60 583	82.6	56 367	82.5	52 161	81.9	49 421	81.7	45 547	80.6	42 771	80.1	41 943	79.6
		Complicated appendicitis	12 839	17.0	12 735	17.4	11 988	17.5	11 551	18.1	11 095	18.3	10 988	19.4	10 655	19.9	10 744	20.4
	> 20 000 cases per year	Uncomplicated appendicitis	30 344	79.9	32 328	79.5	34 457	79.0	35 413	79.2	37 138	79.3	37 815	78.2	38 369	77.4	37 963	76.3
		Complicated appendicitis	7640	20.1	8329	20.5	9145	21.0	9312	20.8	9668	20.7	10 572	21.8	11 202	22.6	11 814	23.7
Age (years)	< 15	Uncomplicated appendicitis	19 190	86.2	18 379	85.7	17 067	85.4	15 418	84.5	14 184	84.0	13 188	83.0	12 328	81.4	12 065	80.7
		Complicated appendicitis	3083	13.8	3072	14.3	2924	14.6	2838	15.5	2709	16.0	2703	17.0	2811	18.6	2879	19.3
	15–35	Uncomplicated appendicitis	48 561	91.3	48 791	91.1	48 325	90.9	47 634	90.9	47 283	91.0	45 205	90.1	43 809	90.0	42 227	89.2
		Complicated appendicitis	4604	8.7	4746	8.9	4846	9.1	4778	9.1	4684	9.0	4946	9.9	4883	10.0	5104	10.8
	> 35	Uncomplicated appendicitis	25 384	66.0	25 741	66.0	25 432	65.6	24 522	64.9	25 092	65.2	24 969	64.2	25 003	63.8	25 614	63.7
		Complicated appendicitis	12 792	34.0	13 246	34.0	13 363	34.4	13 247	35.1	13 370	34.8	13 911	35.8	14 163	36.2	14 575	36.3
Mortality*1	In-hospital mortality	Uncomplicated appendicitis	57	0.06	38	0.04	47	0.05	28	0.03	29	0.03	21	0.03	27	0.03	23	0.03
		Complicated appendicitis	127	0.62	136	0.65	91	0.43	111	0.53	105	0.51	91	0.42	87	0.40	95	0.42
Complicated course*2	At least one indicator of complicated course	Uncomplicated appendicitis	643	0.7	569	0.6	515	0.6	492	0.6	524	0.6	478	0.6	510	0.6	501	0.6
		Complicated appendicitis	1897	9.3	1927	9.2	1917	9.1	1854	8.9	1988	9.6	2023	9.4	2011	9.2	2001	8.9

*¹ The percentages given indicate the proportion of the total quantity

*² The percentages given indicate the proportion of the subset of uncomplicated (complicated) appendicitis per year