Appendix 1. Studies included in systematic review.

Study	Year	Country	N	QoL tool	Time period	Tumor type	Location	Approach	Preoperative/Postoperative QoL	Prospective/Retrospective	Control group	Follow-up period
Holmes et al15	1995	USA	79	KPS	April 1, 1993–August 31, 1993	Multiple	ACF/MCF/PCF	NS	Preoperative	Prospective	No	3 mo
De Jesús et al17	1996	USA	118	KPS	1983–93	Meningioma	Cavernous sinus	NS	Both	Retrospective	No	Median: 33.8 mo
Lang et al22	1999	UK	14	SF-36, GOS	1993–97	Multiple	ACF	ETBA	Both	Prospective	No	1 y minimum
Walch et al19	2000	Austria	3	KPS	1993–96	Olfactory neuroblastoma	ACF	ESBS, SRS	N/S	Retrospective	No	39–71 mo
Gil et al4	2003	Israel	40	ASBQ	1994–2002	Multiple	ACF	SC	Both	Retrospective	No	Average 26 mo
Gil et al5	2004	Israel	35	ASBQ	N/S	Multiple	ACF	SC	Postoperative	Elements of both	No	4–72 mo
Gil et al6	2004	Israel	35	ASBQ	1994–2002	Multiple	ACF	SC	Both	Retrospective	No	Average 26 mo
Raso et al8	2006	Brazil	22	KPS	1996–2002	Multiple	ACF/MCF/PCF	TBA	Both	Retrospective	No	Average 30.5 mo (range: 3–89 mo)
Tzortzidis et al9	2006	USA	74	KPS	1988–2004	Clival and cranial base chordoma	ACF/LCF/PCF	Multiple (open)	Both	Retrospective	No	96 mo (range: 1–198 mo)
Martinez-Devesa et al26	2006	UK	18	UW-QOL	1992–2003	Multiple	ACF/LCF	Multiple (open and endoscopic)	Postoperative	Prospective	No	N/S
Roser et al13	2006	Germany	132	KPS	1980–2004	Meningioma	ACF/MCF/PCF	NS	Both	Retrospective	Yes	36 mo (range: 12–192) in elderly, 60.2 mo (12–206) in young
Bassiouni et al21	2007	Germany	56	KPS	1990–2003	Olfactory groove meningioma	ACF	Multiple (open)	Postoperative	Retrospective	No	5.6 y (range: 1–13 y)
Fliss et al20	2007	Israel	40	ASBQ, KPS	January 1, 1994–March 4, 2005	Multiple	ACF	SC	Postoperative	Retrospective	No	Mean 33 mo
Woertgen et al29	2007	Germany	12	QoLI	1995–2001	Multiple	ACF	Multiple (open)	Postoperative	Retrospective	No	Mean 40 mo
Samii et al18	2009	Germany	25	KPS	1984–2002	Skull base chondrosarcoma	MCF/PCF	Multiple (open)	Postoperative	Retrospective	No	88 mo (range: 18–212)
Bassiouni et al11	2009	Germany	106	KPS	January 1987–June 2005	Meningioma	Anterior clinoid process	Multiple (open)	Both	Retrospective	No	6.9 y (range: 1.5–18 y)
Palme et al30	2009	Canada	27	FACT-H&N, CES-D, ALHR, MDS	N/S	Multiple	ACF	Cranial, transfacial, craniofacial (open)	Postoperative	Retrospective	No	Minimum 6 mo, median 5 y (range: 0.5–10 y)
Ichinose et al12	2010	Japan	161	KPS	January 1985–December 2005	Skull base meningioma	ACF/MCF/PCF	Multiple (open)	Both	Retrospective	No	95.3 mo (range: 0–262 mo)
Pant et al31	2010	USA	51	ASBQ, SNOT-22	N/S	Multiple	N/S	Endonasal	Postoperative	Prospective	No	N/S (but at least 12 mo)
Ohba et al16	2011	Japan	281	KPS	1980–2004	Skull base meningioma	ACF/MCF/PCF	NS	Both	Retrospective	No	88.4 mo (median: 76)
Little et al37	2012	USA	94	ASK Nasal Inventory-9	October 2010–June 2011	Multiple	ACF	Multiple (open and endoscopic)	Both	Prospective	Yes	3 mo
Di Maio et al10	2012	USA	95	KPS	1988–2011	Clival and cranial base chordoma	ACF/LCF/PCF	Multiple (open and endoscopic)	Both	Retrospective	No	38.3 mo
Georgalas et al36	2012	Holland	91	RSOM-31	2000–10	Multiple	ACF/MCF/PCF	Endonasal (endoscopic and extended approaches)	Postoperative	Prospective	No	Median: 1104 d in standard endoscopic TSH group, 142 d in extended approaches subgroup
Ransom et al23	2012	USA	14	SNOT-22, HUI-2, SF-12	October 2009–September 2010	Multiple	ACF	ESBS	Both	Prospective	No	10 mo
Abergel et al34	2012	Israel	78	ASBQ	2003–10	Multiple	ACF	SC, EE	Postoperative	Retrospective	No	N/S
McCoul et al32	2012	USA	66	ASBQ, SNOT-22	July 2010–July 2011	Multiple	ACF	ESBS	Both	Prospective	No	Median 9 mo (range: 3–15 mo)
McCoul et al33	2012	USA	85	ASBQ, SNOT-22	February 2008–June 2011	Multiple	ACF	ESBS	Both	Prospective	No	Median: 10 mo (range: 2–42 mo)
Little et al38	2013	USA	104	ASK Nasal Inventory-12	October 2011–July 2012	Sellar tumors	ACF	ESBS	Both	Prospective	No	2–4 wk following surgery
Sowerby et al35	2013	Canada	22	SNOT-22 (abbreviated 8-item version)	March 2011–January 2012	Pituitary adenomas (functioning and nonfunctioning) and Rathke cleft cysts	ACF	ESBS	Both	Prospective	No	Average 58 d following surgery (range: 22–166 d)
Abbreviations: ASBQ, Anterior Skull Base Questionnaire; ACF, anterior cranial fossa; ALHR, Atkinson Life Happiness Rating; ASK, Anterior Skull Base Nasal Inventory; CES-D, Centre for Epidemiologic Studies Depression Scale; EE, extended endoscopic; ESBS, endoscopic skull base surgery; (E)TBA,(extended) transbasal approach; FACT-H&N, Functional Assessment of Cancer Therapy-Head & Neck; GOS, Glasgow Outcome Score; HUI-2,Health Utilities Index Mark 2; KPS, Karnofsky Performance Status; LCF, lateral cranial fossa; MCF, middle cranial fossa; MDS, midface dysfunction scale; NS, not specified; PCF, posterior cranial fossa; RSOM-31,Rhinosinusitis Outcome Measure-31; SC, subcranial approach; SF-12/36,Short Form 12/36; SNOT-22,sinonasal outcome-22; SRS, stereotactic radiosurgery; TSH, transsphenoidal hypophysectomy; UW-QOL, University of Washington Quality-of-Life scale.